Publications by authors named "Francesco Maffessanti"

62 Publications

Local electromechanical alterations determine the left ventricle rotational dynamics in CRT-eligible heart failure patients.

Sci Rep 2021 Feb 5;11(1):3267. Epub 2021 Feb 5.

Department of Cardiology and Structural Heart Disease, Medical University of Silesia, Ziołowa 45-47, Katowice, Poland.

Left ventricle, LV wringing wall motion relies on physiological muscle fiber orientation, fibrotic status, and electromechanics (EM). The loss of proper EM activation can lead to rigid-body-type (RBT) LV rotation, which is associated with advanced heart failure (HF) and challenges in resynchronization. To describe the EM coupling and scar tissue burden with respect to rotational patterns observed on the LV in patients with ischemic heart failure with reduced ejection fraction (HFrEF) left bundle branch block (LBBB). Thirty patients with HFrEF/LBBB underwent EM analysis of the left ventricle using an invasive electro-mechanical catheter mapping system (NOGA XP, Biosense Webster). The following parameters were evaluated: rotation angle; rotation velocity; unipolar/bipolar voltage; local activation time, LAT; local electro-mechanical delay, LEMD; total electro-mechanical delay, TEMD. Patients underwent late-gadolinium enhancement cMRI when possible. The different LV rotation pattern served as sole parameter for patients' grouping into two categories: wringing rotation (Group A, n = 6) and RBT rotation (Group B, n = 24). All parameters were aggregated into a nine segment, three sector and whole LV models, and compared at multiple scales. Segmental statistical analysis in Group B revealed significant inhomogeneities, across the LV, regarding voltage level, scar burdening, and LEMD changes: correlation analysis showed correspondently a loss of synchronization between electrical (LAT) and mechanical activation (TEMD). On contrary, Group A (relatively low number of patients) did not present significant differences in LEMD across LV segments, therefore electrical (LAT) and mechanical (TEMD) activation were well synchronized. Fibrosis burden was in general associated with areas of low voltage. The rotational behavior of LV in HF/LBBB patients is determined by the local alteration of EM coupling. These findings serve as a strong basic groundwork for a hypothesis that EM analysis may predict CRT response.Clinical trial registration: SUM No. KNW/0022/KB1/17/15.
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http://dx.doi.org/10.1038/s41598-021-82793-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7865069PMC
February 2021

Regional shape, global function and mechanics in right ventricular volume and pressure overload conditions: a three-dimensional echocardiography study.

Int J Cardiovasc Imaging 2021 Jan 3. Epub 2021 Jan 3.

Department of Cardiological, Neural and Metabolic Sciences, Istituto Auxologico Italiano, IRCCS, Milan, Italy.

Our aim was to assess the regional right ventricular (RV) shape changes in pressure and volume overload conditions and their relations with RV function and mechanics. The end-diastolic and end-systolic RV endocardial surfaces were analyzed with three-dimensional echocardiography (3DE) in 33 patients with RV volume overload (rToF), 31 patients with RV pressure overload (PH), and 60 controls. The mean curvature of the RV inflow (RVIT) and outflow (RVOT) tracts, RV apex and body (both divided into free wall (FW) and septum) were measured. Zero curvature defined a flat surface, whereas positive or negative curvature indicated convexity or concavity, respectively. The longitudinal and radial RV wall motions were also obtained. rToF and PH patients had flatter FW (body and apex) and RVIT, more convex interventricular septum (body and apex) and RVOT than controls. rToF demonstrated a less bulging interventricular septum at end-systole than PH patients, resulting in a more convex shape of the RVFW (r = - 0.701, p < 0.0001), and worse RV longitudinal contraction (r = - 0.397, p = 0.02). PH patients showed flatter RVFW apex at end-systole compared to rToF (p < 0.01). In both groups, a flatter RVFW apex was associated with worse radial RV contraction (r = 0.362 in rToF, r = 0.482 in PH at end-diastole, and r = 0.555 in rToF, r = 0.379 in PH at end-systole, respectively). In PH group, the impairment of radial contraction was also related to flatter RVIT (r = 0.407) and more convex RVOT (r = - 0.525) at end-systole (p < 0.05). In conclusion, different loading conditions are associated to specific RV curvature changes, that are related to longitudinal and radial RV dysfunction.
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http://dx.doi.org/10.1007/s10554-020-02117-8DOI Listing
January 2021

Reconstruction of three-dimensional biventricular activation based on the 12-lead electrocardiogram via patient-specific modelling.

Europace 2020 Nov 26. Epub 2020 Nov 26.

Center for Computational Medicine in Cardiology, Institute of Computational Science, Università della Svizzera italiana, Via Giuseppe Buffi 13, CH-6904 Lugano, Switzerland.

Aims: Non-invasive imaging of electrical activation requires high-density body surface potential mapping. The nine electrodes of the 12-lead electrocardiogram (ECG) are insufficient for a reliable reconstruction with standard inverse methods. Patient-specific modelling may offer an alternative route to physiologically constraint the reconstruction. The aim of the study was to assess the feasibility of reconstructing the fully 3D electrical activation map of the ventricles from the 12-lead ECG and cardiovascular magnetic resonance (CMR).

Methods And Results: Ventricular activation was estimated by iteratively optimizing the parameters (conduction velocity and sites of earliest activation) of a patient-specific model to fit the simulated to the recorded ECG. Chest and cardiac anatomy of 11 patients (QRS duration 126-180 ms, documented scar in two) were segmented from CMR images. Scar presence was assessed by magnetic resonance (MR) contrast enhancement. Activation sequences were modelled with a physiologically based propagation model and ECGs with lead field theory. Validation was performed by comparing reconstructed activation maps with those acquired by invasive electroanatomical mapping of coronary sinus/veins (CS) and right ventricular (RV) and left ventricular (LV) endocardium. The QRS complex was correctly reproduced by the model (Pearson's correlation r = 0.923). Reconstructions accurately located the earliest and latest activated LV regions (median barycentre distance 8.2 mm, IQR 8.8 mm). Correlation of simulated with recorded activation time was very good at LV endocardium (r = 0.83) and good at CS (r = 0.68) and RV endocardium (r = 0.58).

Conclusion: Non-invasive assessment of biventricular 3D activation using the 12-lead ECG and MR imaging is feasible. Potential applications include patient-specific modelling and pre-/per-procedural evaluation of ventricular activation.
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http://dx.doi.org/10.1093/europace/euaa330DOI Listing
November 2020

Short-Term Ventricular Structural Changes Following Left Ventricular Assist Device Implantation.

ASAIO J 2021 02;67(2):169-176

From the Department of Medicine, New York Presbyterian Hospital-Columbia University Medical Center, New York.

Reverse remodeling of the left ventricle has been reported following left ventricular assist device (LVAD) implantation. However, left ventricular (LV) and right ventricular (RV) volumetric and shape changes have not been described. Consecutive candidates for LVAD were prospectively enrolled. Comprehensive 2- and 3-dimensional echocardiographic (2DE, 3DE) images were acquired before and 1 to 2 months following LVAD implantation. 3D endocardial surfaces were analyzed to derive shape indices, including LV sphericity and conicity and RV septal and free-wall curvatures. Sixty patients were enrolled with a mean age 56 ± 13 years, 77% male, and 83% destination therapy. 3DE showed that LV end-diastolic volume (EDV) improved from 461 ± 182 to 287 ± 144 ml (p < 0.001) and RV EDV showed no change (p = 0.08). RV longitudinal strain (LS) worsened from -9.1 ± 3.1 to -5.9 ± 2.6% (p < 0.01). LV sphericity and conicity improved (p < 0.001 for both), whereas the curvature of the interventricular septum and RV free wall did not change (p = 0.79 and 0.26, respectively). At 1 month following LVAD implantation, LV volumes decrease dramatically, and there is a favorable LV shape improvement, indicating reverse remodeling. RV shape did not change, whereas RV LS worsened, indicating an absence of RV reverse remodeling.
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http://dx.doi.org/10.1097/MAT.0000000000001214DOI Listing
February 2021

The influence of scar on the spatio-temporal relationship between electrical and mechanical activation in heart failure patients.

Europace 2020 05;22(5):777-786

Center for Computational Medicine in Cardiology, Università della Svizzera italiana, Via G. Buffi 13, CH-6900 Lugano, Switzerland.

Aims: The aim of this study was to determine the relationship between electrical and mechanical activation in heart failure (HF) patients and whether electromechanical coupling is affected by scar.

Methods And Results: Seventy HF patients referred for cardiac resynchronization therapy or biological therapy underwent endocardial anatomo-electromechanical mapping (AEMM) and delayed-enhancement magnetic resonance (CMR) scans. Area strain and activation times were derived from AEMM data, allowing to correlate mechanical and electrical activation in time and space with unprecedented accuracy. Special attention was paid to the effect of presence of CMR-evidenced scar. Patients were divided into a scar (n = 43) and a non-scar group (n-27). Correlation between time of electrical and mechanical activation was stronger in the non-scar compared to the scar group [R = 0.84 (0.72-0.89) vs. 0.74 (0.52-0.88), respectively; P = 0.01]. The overlap between latest electrical and mechanical activation areas was larger in the absence than in presence of scar [72% (54-81) vs. 56% (36-73), respectively; P = 0.02], with smaller distance between the centroids of the two regions [10.7 (4.9-17.4) vs. 20.3 (6.9-29.4) % of left ventricular radius, P = 0.02].

Conclusion: Scar decreases the association between electrical and mechanical activation, even when scar is remote from late activated regions.
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http://dx.doi.org/10.1093/europace/euz346DOI Listing
May 2020

Impact of Severe Pulmonary Arterial Hypertension on the Left Heart and Prognostic Implications.

J Am Soc Echocardiogr 2019 09 2;32(9):1128-1137. Epub 2019 Jul 2.

Section of Cardiology, Department of Medicine, University of Chicago, Chicago, Illinois. Electronic address:

Background: Severe pulmonary arterial hypertension (sPAH) results in a dilated and dysfunctional right ventricle (RV) together with a small left ventricle (LV) with preserved systolic function. RV size and function parameters have an established association with poor prognosis in sPAH. We sought to determine the impact of RV geometry and function on LV mechanics and its relationship with mortality.

Methods: We studied 114 patients (54 ± 13 years) with sPAH, normal LV ejection fraction (LVEF), and complete two-dimensional transthoracic echocardiograms (TTE) and compared them with 70 normal controls of similar age and gender distribution. TTE measurements of atrial sizes, ventricular volumes and function, tricuspid and mitral regurgitation (TR, MR), and LV diastolic function were performed. Speckle-tracking strain was measured in all four chambers, including LV global longitudinal strain (GLS). Cox proportional hazards regression with forward selection was performed to determine the associations between measured indices and mortality over a 20-month follow-up period. Kaplan-Meier curves were generated for variables most associated with death.

Results: Compared with controls, sPAH patients had greater TR severity and right-chamber size with worse function. Of note, LVEF was normal in both groups. Left atrial peak strain and LV GLS were reduced in sPAH, with greater reductions in nonsurvivors. In multivariate analysis, right atrial volume index (hazard ratio [HR] = 1.02 [CI, 1.01-1.04], P < .01), RV free-wall strain (HR = 1.08; CI [1.01-1.15]; P = .03), and LV GLS (HR = 1.11 [CI, 1.01-1.22]; P = .04) were independently associated with mortality.

Conclusions: Although PAH is predominantly a right heart disease, in our cohort of sPAH with normal LVEF, LV GLS was independently associated with death in addition to RV and right atrial abnormalities. These findings indicate that the role of left heart dysfunction in sPAH may be underappreciated in clinical practice.
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http://dx.doi.org/10.1016/j.echo.2019.05.008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7147873PMC
September 2019

Hemodynamic impact of coronary stenosis using computed tomography: comparison between noninvasive fractional flow reserve and 3D fusion of coronary angiography with stress myocardial perfusion.

Int J Cardiovasc Imaging 2019 Sep 9;35(9):1733-1743. Epub 2019 May 9.

Department of Medicine, Section of Cardiology, University of Chicago Medical Center, 5758 South Maryland Avenue, M.C. 9067, Chicago, IL, 60637, USA.

Vasodilator-stress CT perfusion imaging in addition to CT coronary angiography (CTCA) may provide a single-test alternative to nuclear stress testing, commonly used to assess hemodynamic significance of stenosis. Another alternative is fractional flow reserve (FFR) calculated from cardiac CT images. We studied the concordance between these two approaches and their relationship to outcomes. We prospectively studied 150 patients with chest pain, who underwent CTCA and regadenoson CT. CTCA images were interpreted for presence and severity of stenosis. Fused 3D displays of subendocardial X-ray attenuation with coronary arteries were created to detect stress perfusion defects (SPD) in each coronary territory. In patients with stenosis > 25%, CT-FFR was quantified. Significant stenosis was determined by: (1) combination of stenosis > 50% with an SPD, (2) CT-FFR ≤ 0.80. Patients were followed-up for 36 ± 25 months for death, myocardial infarction or revascularization. After excluding patients with normal arteries and technical/quality issues, in final analysis of 76 patients, CTCA depicted stenosis > 70% in 13/224 arteries, 50-70% in 24, and < 50% in 187. CT-FFR ≤ 0.80 was found in 41/224 arteries, and combination of SPD with > 50% stenosis in 31/224 arteries. Inter-technique agreement was 89%. Despite high incidence of abnormal CT-FFR (30/76 patients), only 7 patients experienced adverse outcomes; 6/7 also had SPDs. Only 1/9 patients with CT-FFR ≤ 0.80 but normal perfusion had an event. Fusion of CTCA and stress perfusion can help determine the hemodynamic impact of stenosis in one test, in good agreement with CT-FFR. Adding stress CT perfusion analysis may help risk-stratify patients with abnormal CT-FFR.
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http://dx.doi.org/10.1007/s10554-019-01618-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7081838PMC
September 2019

A left bundle branch block activation sequence and ventricular pacing influence voltage amplitudes: an in vivo and in silico study.

Europace 2018 Nov;20(suppl_3):iii77-iii86

Center for Computational Medicine in Cardiology (CCMC), Institute of Computational Science, Università della Svizzera italiana, Lugano, Switzerland.

Aims: The aim of this study was to investigate the influence of the activation sequence on voltage amplitudes by evaluating regional voltage differences during a left bundle branch block (LBBB) activation sequence vs. a normal synchronous activation sequence and by evaluating pacing-induced voltage differences.

Methods And Results: Twenty-one patients and three computer models without scar were studied. Regional voltage amplitudes were evaluated in nine LBBB patients who underwent endocardial electro-anatomic mapping (EAM). Pacing-induced voltage differences were evaluated in 12 patients who underwent epicardial EAM during intrinsic rhythm and right ventricular (RV) pacing. Three computer models customized for LBBB patients were created. Changes in voltage amplitudes after an LBBB (intrinsic), a normal synchronous, an RV pacing, and a left ventricular pacing activation sequence were assessed in the computer models. Unipolar voltage amplitudes in patients were approximately 4.5 mV (4.4-4.7 mV, ∼33%) lower in the septum when compared with other segments. A normal synchronous activation sequence in the computer models normalized voltage amplitudes in the septum. Pacing-induced differences were larger in electrograms with higher voltage amplitudes during intrinsic rhythm and furthermore larger and more variable at the epicardium [mean absolute difference: 3.6-6.2 mV, 40-53% of intrinsic value; interquartile range (IQR) differences: 53-63% of intrinsic value] compared to the endocardium (mean absolute difference: 3.3-3.8 mV, 28-30% of intrinsic value; IQR differences: 37-40% of intrinsic value).

Conclusion: In patients and computer models without scar, lower septal unipolar voltage amplitudes are exclusively associated with an LBBB activation sequence. Pacing substantially affects voltage amplitudes, particularly at the epicardium.
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http://dx.doi.org/10.1093/europace/euy233DOI Listing
November 2018

Echocardiographic Changes in Patients Implanted With a Fully Magnetically Levitated Left Ventricular Assist Device (Heartmate 3).

J Card Fail 2019 Jan 22;25(1):36-43. Epub 2018 Nov 22.

Department of Cardiothoracic, Transplantation, and Vascular Surgery, Hannover Medical School, Hannover, Germany.

Background: The Heartmate 3 (HM3) is a Conformiteé Européenne mark-approved left ventricular (LV) assist device (LVAD) with fully magnetically levitated rotor and features consisting of a wide range operational speeds, wide flow paths, and artificial pulse. We performed a hemodynamic-echocardiographic speed optimization evaluation in HM3-implanted patients to achieve optimal LV- and right ventricular (RV) shape.

Methods And Results: Sixteen HM3 patients underwent pump speed ramp tests with right heart catheterization. Three-dimensional echocardiographic (3DE) LV and RV datasets (Philips) were acquired, and volumetric (Tomtec) and shape (custom software) analyses were performed (LV: sphericity, conicity; RV: septal and free-wall curvatures). Data were recorded at up to 13 speed settings. Speed changes were in 100-rpm steps, starting at 4600 rpm and ramping up to 6200 rpm. 3DE was feasible in 50% of the patients. Mean original speed was 5306 ± 148 rpm. LV end-diastolic (ED) diameter (-0.15 ± 0.09 cm/100 rpm) and volumes (ED: 269 ± 109 mL to 175 ± 90 mL; end-systolic [ES]: 234 ± 111 mL to 146 ± 81 mL) progressively decreased as the shape became less spherical and more conical; RV volumes initially remained stable, but at higher speeds increased (ED: from 148 ± 64 mL to 181 ± 92 mL; ES: 113 ± 63 mL to 130 ± 69 mL). On average, the RV septum became less convex (bulging toward the LV) at the highest speeds.

Conclusions: LV and RV shape changes were noted in HM3-supported patients. Although a LV volumetric decrease and shape improvement was consistently noted, RV volumes grew in response to increase in speed above a certain point. A next concern would be whether understanding of morphologic and function changes in LV and RV during LVAD speed change assessed with the use of 3DE helps to optimize LVAD speed settings and improve clinical outcomes.
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http://dx.doi.org/10.1016/j.cardfail.2018.11.015DOI Listing
January 2019

Peak left atrial strain as a single measure for the non-invasive assessment of left ventricular filling pressures.

Int J Cardiovasc Imaging 2019 Jan 30;35(1):23-32. Epub 2018 Jul 30.

University of Chicago Medical Center, Chicago, IL, USA.

Echocardiographic assessment of left ventricular (LV) filling pressures is performed using a multi-parametric algorithm. Left atrial (LA) strain was recently found to accurately classify the degree of diastolic dysfunction. We hypothesized that LA strain could be used as a stand-alone marker and sought to identify and test a cutoff, which would accurately detect elevated LV pressures. We studied 76 patients with a spectrum of LV function who underwent same-day echocardiogram and invasive left-heart catheterization. Speckle tracking was used to measure peak LA strain. The protocol involved a retrospective derivation group (N = 26) and an independent prospective validation cohort (N = 50) to derive and then test a peak LA strain cutoff which would identify pre-A-wave LV diastolic pressure > 15 mmHg. The guidelines-based assessment of filling pressures and peak LA strain were compared side-by-side against invasive hemodynamic data. In the derivation cohort, receiver-operating characteristic analysis showed area under curve of 0.76 and a peak LA strain cutoff < 20% was identified as optimal to detect elevated filling pressure. In the validation cohort, peak LA strain demonstrated better agreement with the invasive reference (81%) than the guidelines algorithm (72%). The improvement in classification using LA strain compared to the guidelines was more pronounced in subjects with normal LV function (91% versus 81%). In summary, the use of a peak LA strain to estimate elevated LV filling pressures is more accurate than the current guidelines. Incorporation of LA strain into the non-invasive assessment of LV diastolic function may improve the detection of elevated filling pressures.
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http://dx.doi.org/10.1007/s10554-018-1425-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6353699PMC
January 2019

Value of high-resolution mapping in optimizing cryoballoon ablation of atrial fibrillation.

Int J Cardiol 2018 Nov 1;270:136-142. Epub 2018 Jun 1.

Division of Cardiology, Cardiocentro Ticino, Lugano, Switzerland; Centre for Computational Medicine in Cardiology, Faculty of Informatics, Università della Svizzera Italiana, Lugano, Switzerland.

Background: Unrecognized incomplete pulmonary vein isolation (PVI), as opposed to post-PVI pulmonary vein reconnection, may be responsible for clinical recurrences of atrial fibrillation (AF). To date, no data are available on the use of high-resolution mapping (HRM) during cryoballoon (CB) ablation for AF as the index procedure. The aims of this study were: - to assess the value of using a HRM system during CB ablation procedures in terms of ability in acutely detecting incomplete CB lesions; - to compare the 8-pole circular mapping catheter (CMC, Achieve) and the 64-pole mini-basket catheter (Orion) with respect to pulmonary vein (PV) signals detection at baseline and after CB ablation; - to characterize the extension of the lesion produced by CB ablation by means of high-density voltage mapping.

Methods: Consecutive patients with drug-resistant paroxysmal or early-persistent AF undergoing CB ablation as the index procedure, assisted by a HRM system, were retrospectively included in this study.

Results: A total of 33 patients (25 males; mean age: 59 ± 18 years, 28 paroxysmal AF) were included. At baseline, CMC catheter revealed PV activity in 102 PVs (77%), while the Orion documented PV signals in all veins (100%). Failure of complete CB-PVI was more frequently revealed by atrial re-mapping with the Orion as compared to the Achieve catheter (24% vs 0%, p < 0.05). A repeat ablation was performed in 8 patients (24%). In 9% of cases, the Orion catheter detected far-field signals originating from the right atrium. Quantitative assessment of the created lesion revealed a significant reduction of the left atrial area having voltage >0.5 mV. A total of 29 patients (88%) remained free of symptomatic AF during a mean follow-up of 13.2 ± 3.7 months.

Conclusion: Atrial re-mapping after CB ablation by means of a HRM system improves the detection of areas of incomplete ablation, characterizes the extension of the cryo-ablated tissue and can identify abolishment of potential non-PVI related sources of AF.
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http://dx.doi.org/10.1016/j.ijcard.2018.05.135DOI Listing
November 2018

Reference values of left heart echocardiographic dimensions and mass in male peri-pubertal athletes.

Eur J Prev Cardiol 2018 07 18;25(11):1204-1215. Epub 2018 May 18.

4 Department of Health Sciences, University of Rome 'Foro Italico', Italy.

Background Several articles have proposed reference values in healthy paediatric subjects, but none of them has evaluated a large population of healthy trained adolescents. Design The study purpose was to establish normal echocardiographic measurements of left heart (aortic root, left atrium and left ventricular dimensions and mass) in relation to age, weight, height, body mass index, body surface area and training hours in this specific population. Methods We retrospectively evaluated 2151 consecutive, healthy, peri-pubertal athletes (100% male, mean age 12.4 ± 1.4 years, range 8-18) referred to a single centre for pre-participation screening. All participants were young soccer athletes who trained for a mean of 7.2 ± 1.1 h per week. Results Left ventricular internal diameters, wall thickness, left ventricular mass, aortic root and left atrium diameters were significantly correlated to age, body surface area, height and weight ( p < 0.01). Age, height, weight and body surface area were found associated with chamber size, while body mass index and training hours were not. Inclusion of both age and body size parameters in the statistical models resulted in improved overall explained variance for diameters and left ventricular mass. Conclusion Equations, mean values and percentile charts for the different age groups may be useful as reference data in efficiently assessing left ventricular parameters in young athletes.
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http://dx.doi.org/10.1177/2047487318776084DOI Listing
July 2018

Integrated Assessment of Left Ventricular Electrical Activation and Myocardial Strain Mapping in Heart Failure Patients: A Holistic Diagnostic Approach for Endocardial Cardiac Resynchronization Therapy, Ablation of Ventricular Tachycardia, and Biological Therapy.

JACC Clin Electrophysiol 2018 01 6;4(1):138-146. Epub 2017 Nov 6.

Center for Computational Medicine in Cardiology, Institute of Computational Science, Università della Svizzera italiana, Lugano, Switzerland; Division of Cardiology, Fondazione Cardiocentro Ticino, Lugano, Switzerland.

Objectives: This study sought to test the accuracy of strain measurements based on anatomo-electromechanical mapping (AEMM) measurements compared with magnetic resonance imaging (MRI) tagging, to evaluate the diagnostic value of AEMM-based strain measurements in the assessment of myocardial viability, and the additional value of AEMM over peak-to-peak local voltages.

Background: The in vivo identification of viable tissue, evaluation of mechanical contraction, and simultaneous left ventricular activation is currently achieved using multiple complementary techniques.

Methods: In 33 patients, AEMM maps (NOGA XP, Biologic Delivery Systems, Division of Biosense Webster, a Johnson & Johnson Company, Irwindale, California) and MRI images (Siemens 3T, Siemens Healthcare, Erlangen, Germany) were obtained within 1 month. MRI tagging was used to determine circumferential strain (E) and delayed enhancement to obtain local scar extent (%). Custom software was used to measure E and local area strain (LAS) from the motion field of the AEMM catheter tip.

Results: Intertechnique agreement for E was good (R = 0.80), with nonsignificant bias (0.01 strain units) and narrow limits of agreement (-0.03 to 0.06). Scar segments showed lower absolute strain amplitudes compared with nonscar segments: E (median [first to third quartile]: nonscar -0.10 [-0.15 to -0.06] vs. scar -0.04 [-0.06 to -0.02]) and LAS (-0.20 [-0.27 to -0.14] vs. -0.09 [-0.14 to -0.06]). AEMM strains accurately discriminated between scar and nonscar segments, in particular LAS (area under the curve: 0.84, accuracy = 0.76), which was superior to peak-to-peak voltages (nonscar 9.5 [6.5 to 13.3] mV vs. scar 5.6 [3.4 to 8.3] mV; area under the curve: 0.75). Combination of LAS and peak-to-peak voltages resulted in 86% accuracy.

Conclusions: An integrated AEMM approach can accurately determine local deformation and correlates with the scar extent. This approach has potential immediate application in the diagnosis, delivery of intracardiac therapies, and their intraprocedural evaluation.
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http://dx.doi.org/10.1016/j.jacep.2017.08.011DOI Listing
January 2018

Fusion of Three-Dimensional Echocardiographic Regional Myocardial Strain with Cardiac Computed Tomography for Noninvasive Evaluation of the Hemodynamic Impact of Coronary Stenosis in Patients with Chest Pain.

J Am Soc Echocardiogr 2018 06 22;31(6):664-673. Epub 2018 Mar 22.

Section of Cardiology, University of Chicago Medicine, Chicago, Illinois.

Background: Combined evaluation of coronary stenosis and the extent of ischemia is essential in patients with chest pain. Intermediate-grade stenosis on computed tomographic coronary angiography (CTCA) frequently triggers downstream nuclear stress testing. Alternative approaches without stress and/or radiation may have important implications. Myocardial strain measured from echocardiographic images can be used to detect subclinical dysfunction. The authors recently tested the feasibility of fusion of three-dimensional (3D) echocardiography-derived regional resting longitudinal strain with coronary arteries from CTCA to determine the hemodynamic significance of stenosis. The aim of the present study was to validate this approach against accepted reference techniques.

Methods: Seventy-eight patients with chest pain referred for CTCA who also underwent 3D echocardiography and regadenoson stress computed tomography were prospectively studied. Left ventricular longitudinal strain data (TomTec) were used to generate fused 3D displays and detect resting strain abnormalities (RSAs) in each coronary territory. Computed tomographic coronary angiographic images were interpreted for the presence and severity of stenosis. Fused 3D displays of subendocardial x-ray attenuation were created to detect stress perfusion defects (SPDs). In patients with stenosis >25% in at least one artery, fractional flow reserve was quantified (HeartFlow). RSA as a marker of significant stenosis was validated against two different combined references: stenosis >50% on CTCA and SPDs seen in the same territory (reference standard A) and fractional flow reserve < 0.80 and SPDs in the same territory (reference standard B).

Results: Of the 99 arteries with no stenosis >50% and no SPDs, considered as normal, 19 (19%) had RSAs. Conversely, with stenosis >50% and SPDs, RSAs were considerably more frequent (17 of 24 [71%]). The sensitivity, specificity, and accuracy of RSA were 0.71, 0.81, and 0.79, respectively, against reference standard A and 0.83, 0.81, and 0.82 against reference standard B.

Conclusions: Fusion of CTCA and 3D echocardiography-derived resting myocardial strain provides combined displays, which may be useful in determination of the hemodynamic or functional impact of coronary abnormalities, without additional ionizing radiation or stress testing.
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http://dx.doi.org/10.1016/j.echo.2018.01.019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5988992PMC
June 2018

Morphologic Analysis of the Normal Right Ventricle Using Three-Dimensional Echocardiography-Derived Curvature Indices.

J Am Soc Echocardiogr 2018 05 21;31(5):614-623. Epub 2018 Feb 21.

University of Chicago, Chicago, Illinois.

Background: Right ventricular (RV) remodeling involves changes in size, wall thickness, function, and shape. Previous studies have suggested that regional curvature indices (rCI) may be useful for RV shape analysis. The aim of this study was to establish normal three-dimensional echocardiographic values of rCI in a large group of healthy subjects to facilitate future three-dimensional echocardiographic study of adverse RV remodeling.

Methods: RV endocardial surfaces were reconstructed at end-diastole and end-systole in 245 healthy subjects (mean age, 42 ± 12 years) and analyzed using custom software to calculate mean curvature in six regions: RV inflow tract (RVIT) and RV outflow tract, apex, and body (both divided into free wall and septal regions). Associations with age and gender were studied.

Results: The apical free wall was convex, while the septum (apex and body) was more concave than the body free wall. Septal curvature did not change significantly from end-diastole to end-systole. The RV outflow tract and RVIT became flatter from end-diastole to end-systole. In keeping with the "bellows-like" action of RV contraction, the body free wall became flatter, while the apex free wall changed to a more convex surface. There were no intergender differences in rCI. In older subjects (≥55 years of age), the RV free wall and RV outflow tract were flatter, and from end-diastole to end-systole, the RVIT became less flattened and the apex less pointed. These changes suggest that the right ventricle is stiffer in older subjects, with less dynamic contraction of the RVIT and less bellows-like movement.

Conclusions: This study established normal three-dimensional echocardiographic values for RV rCI, which are needed to further study RV diastolic dysfunction and remodeling with disease.
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http://dx.doi.org/10.1016/j.echo.2017.12.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5936650PMC
May 2018

2D and 3D Echocardiography-Derived Indices of Left Ventricular Function and Shape: Relationship With Mortality.

JACC Cardiovasc Imaging 2018 11 15;11(11):1569-1579. Epub 2017 Nov 15.

Department of Medicine, University of Chicago Medical Center, Chicago, Illinois. Electronic address:

Objectives: This study hypothesized that left ventricular (LV) ejection fraction (EF) and global longitudinal strain (GLS) derived from 3-dimensional echocardiographic (3DE) images would better predict mortality than those obtained by 2-dimensional echocardiographic (2DE) measurements, and that 3DE-based LV shape analysis may have added prognostic value.

Background: Previous studies have shown that both LVEF and GLS derived from 2DE images predict mortality. Recently, 3DE measurements of these parameters were found to be more accurate and reproducible because of independence of imaging plane and geometric assumptions. Also, 3DE analysis offers an opportunity to accurately quantify LV shape.

Methods: We retrospectively studied 416 inpatients (60 ± 18 years of age) referred for transthoracic echocardiography between 2006 and 2010, who had good-quality 2DE and 3DE images were available. Mortality data through 2016 were collected. Both 2DE and 3DE images were analyzed to measure LVEF and GLS. Additionally, 3DE-derived LV endocardial surface information was analyzed to obtain global shape indices (sphericity and conicity) and regional curvature (anterior, septal, inferior, lateral walls). Cardiovascular (CV) mortality risks related to these indices were determined using Cox regression.

Results: Of the 416 patients, 208 (50%) died, including 114 (27%) CV-related deaths over a mean follow-up period of 5 ± 3 years. Cox regression revealed that age and body surface area, all 4 LV function indices (2D EF, 3D EF, 2D GLS, 3D GLS), and regional shape indices (septal and inferior wall curvatures) were independently associated with increased risk of CV mortality. GLS was the strongest prognosticator of CV mortality, superior to EF for both 2DE and 3DE analyses, and 2D EF was the weakest among the 4 functional indices. A 1% decrease in GLS magnitude was associated with an 11.3% increase in CV mortality risk.

Conclusions: GLS predicts mortality better than EF by both 3DE and 2DE analysis, whereas 3D EF is a better predictor than 2D EF. Also, LV shape indices provide additional risk assessment.
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http://dx.doi.org/10.1016/j.jcmg.2017.08.023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5945352PMC
November 2018

Evaluation of the use of unipolar voltage amplitudes for detection of myocardial scar assessed by cardiac magnetic resonance imaging in heart failure patients.

PLoS One 2017 5;12(7):e0180637. Epub 2017 Jul 5.

Center for Computational Medicine in Cardiology, Institute of Computational Science, Università della Svizzera italiana, Lugano, Switzerland.

Background: Validation of voltage-based scar delineation has been limited to small populations using mainly endocardial measurements. The aim of this study is to compare unipolar voltage amplitudes (UnipV) with scar on delayed enhancement cardiac magnetic resonance imaging (DE-CMR).

Methods: Heart failure patients who underwent DE-CMR and electro-anatomic mapping were included. Thirty-three endocardial mapped patients and 27 epicardial mapped patients were investigated. UnipV were computed peak-to-peak. Electrograms were matched with scar extent of the corresponding DE-CMR segment using a 16-segment/slice model. Non-scar was defined as 0% scar, while scar was defined as 1-100% scar extent.

Results: UnipVs were moderately lower in scar than in non-scar (endocardial 7.1 [4.6-10.6] vs. 10.3 [7.4-14.2] mV; epicardial 6.7 [3.6-10.5] vs. 7.8 [4.2-12.3] mV; both p<0.001). The correlation between UnipV and scar extent was moderate for endocardial (R = -0.33, p<0.001), and poor for epicardial measurements (R = -0.07, p<0.001). Endocardial UnipV predicted segments with >25%, >50% and >75% scar extent with AUCs of 0.72, 0.73 and 0.76, respectively, while epicardial UnipV were poor scar predictors, independent of scar burden (AUC = 0.47-0.56). UnipV in non-scar varied widely between patients (p<0.001) and were lower in scar compared to non-scar in only 9/22 (41%) endocardial mapped patients and 4/19 (21%) epicardial mapped patients with scar.

Conclusion: UnipV are slightly lower in scar compared to non-scar. However, significant UnipV differences between and within patients and large overlap between non-scar and scar limits the reliability of accurate scar assessment, especially in epicardial measurements and in segments with less than 75% scar extent.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0180637PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5498065PMC
October 2017

3D Morphological Changes in LV and RV During LVAD Ramp Studies.

JACC Cardiovasc Imaging 2018 02 12;11(2 Pt 1):159-169. Epub 2017 Apr 12.

Department of Medicine, Section of Cardiology, University of Chicago, Chicago, Illinois. Electronic address:

Objectives: The purpose of this study was to investigate the differential impact of the 2 most commonly available left ventricular assist device (LVAD) types on the right ventricle (RV) and left ventricle (LV) using 3-dimensional (3D) echocardiography-based analysis of ventricular morphology.

Background: LVADs have emerged as common therapy for advanced heart failure. Recent data suggest that the heart responds differently to speed settings in the 2 main devices available (HeartMate II [HMII], St Jude Medical, Pleasanton, California, and HVAD, HeartWare International, Framingham, Massachusetts). The authors hypothesized that 3D echocardiographic assessment of LV and RV volumes and shape would help describe the differential impact of the 2 LVAD types on the heart.

Methods: Simultaneous 3D echocardiography, ramp test, and right heart catheterization were performed in 31 patients with LVADs (19 with HMII and 12 with HVAD). Device speed was increased stepwise (8,000 to 12,000 for HMII and 2,300 to 3,200 revolutions per minute for HVAD). 3D echocardiographic full-volume LV and RV datasets were acquired, and endocardial surfaces were analyzed using custom software to calculate LV sphericity, conicity (perfect sphere/cone = 1) and RV septal and free-wall curvature (0 = flat; <0 = concave; >0 = convex).

Results: For both devices, cardiac output increased and wedge pressure decreased with increasing speed. In HMII, LV volumes progressively decreased (meanΔ = 127 ml) as the LV became less spherical and more conical, whereas the RV volume initially remained stable, but subsequently increased at higher speeds (meanΔ = 60 ml). Findings for the HVAD were similar, but less pronounced (LV:meanΔ = 51 ml, RV:meanΔ = 22 ml), and the LV remained significantly more spherical even at high speeds. On average, in HMII patients, the RV septum became more convex (bulging into the LV) at the highest speeds whereas in HVAD patients, there was no discernable change in the RV septum.

Conclusions: The heart responds differently to pump speed changes with the 2 types of LVAD, as reflected by the volume and shape changes of both the LV and RV. Our study suggests that adding RV assessment to the clinical echo-ramp study may better optimize LVAD speed. Further study is needed to determine whether this would have an impact on patient outcomes.
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http://dx.doi.org/10.1016/j.jcmg.2016.12.019DOI Listing
February 2018

The relation between local repolarization and T-wave morphology in heart failure patients.

Int J Cardiol 2017 Aug 22;241:270-276. Epub 2017 Feb 22.

Maastricht University, Maastricht, The Netherlands. Electronic address:

Background: Both duration and morphology of the T-wave are regarded important parameters describing repolarization of the ventricles. Conventionally, T-wave concordance is explained by an inverse relation between the time of depolarization (TD) and repolarization (TR). Little is known about T-wave morphology and TD-TR relations in patients with heart failure.

Methods: Electro-anatomic maps were obtained in the left (LV) and right ventricle (RV) and in the coronary sinus (CS) in patients with heart failure with narrow (nQRS, n=8) and wide QRS complex with (LBBB, n=15) and without left bundle branch block (non-LBBB, n=7). TD and TR were determined from the thus acquired electrograms.

Results: In nQRS and non-LBBB patients, TD-TR relations had a slope between 0 and +1, indicating that repolarization followed the sequence of depolarization. In LBBB patients, repolarization occurred significantly earlier in the RV than in the LV, fitting with the idea that the discordant T-waves in LBBB are secondary to the abnormal depolarization sequence. However, the slopes of the TD-TR relations in the LV and CS were not significantly different from zero, indicating no major spatial gradient in LV repolarization, despite a considerable gradient in depolarization. Remarkable was also the large (~100ms) transseptal gradient in repolarization. Values of the slopes of the TD-TR relation overlapped between the three patient groups, despite a difference in T-wave morphology between LBBB (all discordant) and nQRS patients (all flat/biphasic).

Conclusions: Discordant T-waves in LBBB patients are explained by interventricular dispersion in repolarization. T-wave morphology is determined by more factors than the TD-TR relation alone.
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http://dx.doi.org/10.1016/j.ijcard.2017.02.056DOI Listing
August 2017

3D late gadolinium enhanced cardiovascular MR with CENTRA-PLUS profile/view ordering: Feasibility of right ventricular myocardial damage assessment using a swine animal model.

Magn Reson Imaging 2017 06 25;39:7-14. Epub 2017 Jan 25.

Department of Medicine, Section of Cardiology, The University of Chicago, Chicago, IL, United States; Department of Surgery, Section of Cardiothoracic Surgery, The University of Chicago, Chicago, IL, United States.

Aims: To develop a high-resolution, 3D late gadolinium enhancement (LGE) cardiovascular magnetic resonance imaging (MRI) technique for improved assessment of myocardial scars, and evaluate its performance against 2D breath-held (BH) LGE MRI using a surgically implanted animal scar model in the right ventricle (RV).

Methods And Results: A k-space segmented 3D LGE acquisition using CENTRA-PLUS (Contrast ENhanced Timing Robust Acquisition with Preparation of LongitUdinal Signal; or CP) ordering is proposed. 8 pigs were surgically prepared with cardiac patch implantation in the RV, followed in 60days by 1.5T MRI. LGE with Phase-Sensitive Inversion Recovery (PSIR) were performed as follows: 1) 2DBH using pneumatic control, and 2) navigator-gated, 3D free-breathing (3DFB)-CP-LGE with slice-tracking. The animal heart was excised immediately after cardiac MR for scar volume quantification. RV scar volumes were also delineated from the 2DBH and 3DFB-CP-LGE images for comparison against the surgical standard. Apparent scar/normal tissue signal-to-noise ratio (aSNR) and contrast-to-noise ratio (aCNR) were also calculated. 3DFB-CP-LGE technique was successfully performed in all animals. No difference in aCNR was noted, but aSNR was significantly higher using the 3D technique (p<0.05). Against the surgical reference volume, the 3DFB-CP-LGE-derived delineation yielded significantly less volume quantification error compared to 2DBH-derived volumes (15±10% vs 55±33%; p<0.05).

Conclusion: Compared to conventional 2DBH-LGE, 3DFB-LGE acquisition using CENTRA-PLUS provided superior scar volume quantification and improved aSNR.
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http://dx.doi.org/10.1016/j.mri.2017.01.015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5410402PMC
June 2017

LA Strain for Categorization of LV Diastolic Dysfunction.

JACC Cardiovasc Imaging 2017 07 21;10(7):735-743. Epub 2016 Dec 21.

Section of Cardiology, Department of Medicine, University of Chicago Medical Center, Chicago, Illinois. Electronic address:

Objectives: This study sought to observe the relationship between left atrial (LA) strain and left ventricular diastolic function and determine whether LA strain could be used to detect diastolic dysfunction (DD) and classify its degree when present.

Background: The assessment of diastolic function is complex and multiparametric because most conventional parameters do not follow the progression of DD. Strain imaging is an emerging index of LA function, with recent data demonstrating that LA strain is diminished in diastolic heart failure. However, LA strain is not part of the standard assessment of diastolic function. We hypothesized that LA strain decreases with worsening DD in a stepwise fashion and could thus be useful in evaluating DD.

Methods: We performed a retrospective derivation and validation cohort study to derive and test LA strain thresholds for DD grades (0 to 3) in patients with preserved left ventricular ejection fraction (N = 229). Two-dimensional speckle tracking was used to measure peak LA strain, which was applied as a single parameter to classify DD. American Society of Echocardiography guidelines were used as the reference standard.

Results: In the derivation cohort (n = 90), peak LA strain was significantly different between DD groups, with gradual decreases seen with worsening DD. Receiver-operating characteristic analysis resulted in 3 distinct LA strain thresholds for categorization of DD grades, with good to excellent diagnostic utility (area under the curve: 0.86 to 0.91). In an independent validation group (n = 139) with a spectrum of diastolic function, 11 patients (8%) had indeterminate DD grades using standard criteria, whereas LA strain was measured in all patients and its cutoffs resulted in diagnostic accuracy up to 95%.

Conclusions: LA strain measurements are feasible and allow accurate categorization of DD, because unlike the traditional parameters, it changes progressively with severity of DD. LA strain may become a useful tool for diastolic assessment in future clinical practice.
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http://dx.doi.org/10.1016/j.jcmg.2016.08.014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5741456PMC
July 2017

Three-Dimensional Transthoracic Echocardiography in the Comprehensive Evaluation of Right and Left Heart Chamber Remodeling Following Percutaneous Mitral Valve Repair.

J Am Soc Echocardiogr 2016 10 5;29(10):946-954. Epub 2016 Aug 5.

Centro Cardiologico Monzino IRCCS, Milan, Italy.

Background: Percutaneous mitral valve repair (PMVR) is an alternative treatment in patients with significant mitral regurgitation (MR) who are denied surgery. Although in surgical patients, outcomes have been related both to acute hemodynamic favorable results and to positive cardiac remodeling in the midterm, in the case of PMVR the effect on cardiac chamber remodeling has never been extensively studied. The aims of this study were (1) to evaluate the short- and mid-term remodeling induced by PMVR on cardiac chamber volume using two- and three-dimensional (3D) transthoracic echocardiographic (TTE) imaging and (2) to assess changes in left ventricular (LV) shape on the basis of 3D TTE data.

Methods: Patients undergoing PMVR were prospectively enrolled. Two-dimensional and 3D TTE data sets acquired at baseline, and at 30 days and 6 months after PMVR were analyzed to assess LV and right ventricular (RV) volumes and ejection fraction and left atrial and right atrial volumes. Moreover, 3D endocardial surfaces were extracted to compute 3D shape indexes of LV sphericity and conicity at end-diastole and end-systole.

Results: Six of the 64 enrolled patients did not reach follow-up and were excluded. The analysis was feasible in all 58 patients considered (26 with functional MR and 32 [55%] with degenerative MR). PMVR resulted in significant reduction of MR and in favorable remodeling: (1) effective PMVR was mainly associated with decreased LV loading, (2) PMVR-related reverse remodeling was observed in patients with degenerative MR and those with functional MR at 30 days and continued at 6-month follow-up, (3) favorable remodeling in LV shape from abnormally spherical to more normal conical took place in both groups after PMVR, and (4) RV volumes and systolic function were preserved after PMVR.

Conclusions: A comprehensive two-dimensional and 3D TTE analysis allows investigation from a double perspective (volume and morphology) of the entity and modality of changes following PMVR. In high-risk patients undergoing PMVR, postprocedural heart remodeling involves all cardiac chambers, occurs in the short term, and further improves at midterm follow-up.
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http://dx.doi.org/10.1016/j.echo.2016.06.009DOI Listing
October 2016

Non-invasive assessment of the haemodynamic significance of coronary stenosis using fusion of cardiac computed tomography and 3D echocardiography.

Eur Heart J Cardiovasc Imaging 2017 Jun;18(6):670-680

University of Chicago Medical Center, Chicago, IL, USA.

Aims: Abnormal computed tomography coronary angiography (CTCA) often leads to stress testing to determine haemodynamic significance of stenosis. We hypothesized that instead, this could be achieved by fusion imaging of the coronary anatomy with 3D echocardiography (3DE)-derived resting myocardial deformation.

Methods And Results: We developed fusion software that creates combined 3D displays of the coronary arteries with colour maps of longitudinal strain and tested it in 28 patients with chest pain, referred for CTCA (256 Philips scanner) who underwent 3DE (Philips iE33) and regadenoson stress CT. To obtain a reference for stenosis significance, coronaries were also fused with colour maps of stress myocardial perfusion. 3D displays were used to detect stress perfusion defect (SPD) and/or resting strain abnormality (RSA) in each territory. CTCA showed 56 normal arteries, stenosis <50% in 17, and >50% in 8 arteries. Of the 81 coronary territories, SPDs were noted in 20 and RSAs in 29. Of the 59 arteries with no stenosis >50% and no SPDs, considered as normal, 12 (20%) had RSAs. Conversely, with stenosis >50% and SPDs (haemodynamically significant), RSAs were considerably more frequent (5/6 = 83%). Overall, resting strain and stress perfusion findings were concordant in 64/81 arteries (79% agreement).

Conclusions: Fusion of CTCA and 3DE-derived data allows direct visualization of each coronary artery and strain in its territory. In this feasibility study, resting strain showed good agreement with stress perfusion, indicating that it may be potentially used to assess haemodynamic impact of coronary stenosis, as an alternative to stress testing that entails additional radiation exposure.
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http://dx.doi.org/10.1093/ehjci/jew147DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6279096PMC
June 2017

Objective selection of short-axis slices for automated quantification of left ventricular size and function by cardiovascular magnetic resonance.

Clin Imaging 2016 Jul-Aug;40(4):617-23. Epub 2016 Mar 3.

University of Chicago Medical Center, Chicago, IL, USA. Electronic address:

Background: Quantification of left ventricular (LV) volume from cardiovascular magnetic resonance images relies on subjective and often challenging selection of short-axis (SAX) slices. We hypothesized that this could be solved by defining mitral annular (MA) plane and apex in long-axis (LAX) views, which could be combined with automated LV volume analysis that does not rely on manual tracing of the endocardial border.

Methods: SAX images from 50 subjects were analyzed using custom software. LV apex and insertion points of the mitral leaflets were marked on LAX views and used to approximate MA plane. End-systolic and end-diastolic LV volumes (ESV, EDV) were measured while including only slices or their parts located between MA plane and LV apex. Endocardial borders were automatically detected using our previously validated algorithm and also manually traced to obtain reference values.

Results: Selection of anatomic landmarks in LAX views allowed automated measurement of LV volumes without the need for subjective slice selection. Intertechnique comparisons resulted in high correlations (EDV: r=0.95; ESV: r=0.96) and small biases (1 and 9ml). Combined three-dimensional displays of LAX and SAX views with the MA plane showed that in 7/10 worst cases, intertechnique discordance was due to incorrect manual tracing at LV base that erroneously included part of atrial cavity in LV volume or excluded part of LV cavity, i.e., incorrect reference values.

Conclusion: Defining the MA plane and apex in the LAX views obviates the need for subjective slice selection and eliminates errors in LV volume measurements.
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http://dx.doi.org/10.1016/j.clinimag.2016.02.025DOI Listing
December 2016

Ascending Aortic Dimensions in Hypertensive Subjects: Reference Values for Two-Dimensional Echocardiography.

J Am Soc Echocardiogr 2016 09 5;29(9):827-37. Epub 2016 May 5.

Centro Cardiologico Monzino IRCCS, Milan, Italy.

Background: Aortic dilation is an independent predictor of cardiovascular disease. The association between hypertension and aortic dilation is still controversial. Also, most previous research has investigated this relationship regarding only the aortic root, and no information is available for the ascending aorta (AscAo).

Methods: To assess AscAo dimensions in hypertensive patients, 1,027 patients with hypertension and 1,002 healthy volunteers were prospectively enrolled. Aortic diameters at four levels were measured using the leading edge-to-leading edge convention at end-diastole: the sinuses of Valsalva, sinotubular junction (STJ), AscAo, and aortic arch (AoArch), using two-dimensional echocardiography.

Results: All four diameters were significantly larger in hypertensive patients than in control subjects, with positive correlations with age, body size, and male sex. On multivariate analysis, gender and body surface area were independently associated with aortic diameters. The general linear model showed that after adjusting for age, sex, and body surface area, hypertension was positively associated (P < .01) with higher aortic diameter at every level. Hypertension was associated with increases of 1.7 mm (95% CI, 1.2-2.1 mm) at the sinuses of Valsalva, 4.1 mm (95% CI, 3.6-4.6 mm) at the STJ, 1.6 mm (95% CI, 1.1-2.1 mm) at the AscAo, and 2.2 mm (95% CI, 1.7-2.6 mm) at the AoArch. On the basis of nomograms, an abnormally high prevalence of aortic dilation in hypertensive patients was observed for the STJ (14%) and the AoArch (7%).

Conclusions: Systematic analysis of the AscAo in hypertensive patients showed that, together with age, sex, and body surface area, hypertension is an independent factor associated with increases in all four aortic diameters and that aortic dilation occurred more frequently at the level of the STJ and AoArch.
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http://dx.doi.org/10.1016/j.echo.2016.03.016DOI Listing
September 2016

Three-dimensional quantification of myocardial perfusion during regadenoson stress computed tomography.

Eur J Radiol 2016 May 6;85(5):885-92. Epub 2016 Mar 6.

University of Chicago Medical Center, Chicago, IL, United States.

Background: There is no accepted methodology for CT-based vasodilator stress myocardial perfusion imaging and analysis. We developed a technique for quantitative 3D analysis of CT images, which provides several indices of myocardial perfusion. We sought to determine the ability of these indices during vasodilator stress to identify segments supplied by coronary arteries with obstructive disease and to test the accuracy of the detection of perfusion abnormalities against SPECT.

Methods: We studied 93 patients referred for CT coronary angiography (CTCA) who underwent regadenoson stress. 3D analysis of stress CT images yielded segmental perfusion indices: mean X-ray attenuation, severity of defect and relative defect volume. Each index was averaged for myocardial segments, grouped by severity of stenosis: 0%, <50%, 50-70%, and >70%. Objective detection of perfusion abnormalities was optimized in 47 patients and then independently tested in the remaining 46 patients.

Results: CTCA depicted normal coronary arteries or non-obstructive disease in 62 patients and stenosis of >50% in 31. With increasing stenosis, segmental attenuation showed a 7% decrease, defect severity increased 11%, but relative defect volume was 7-fold higher in segments with obstructive disease (p<0.001). In the test group, detection of perfusion abnormalities associated with stenosis >50% showed sensitivity 0.78, specificity 0.54, accuracy 0.59. When compared to SPECT in a subset of 21 patients (14 with abnormal SPECT), stress CT perfusion analysis showed sensitivity 0.79, specificity 0.71, accuracy 0.76.

Conclusions: 3D analysis of vasodilator stress CT images provides quantitative indices of myocardial perfusion, of which relative defect volume was most robust in identifying segments supplied by arteries with obstructive disease. This study may have implications on how CT stress perfusion imaging is performed and analyzed.
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http://dx.doi.org/10.1016/j.ejrad.2016.02.028DOI Listing
May 2016

Delayed Anaerobic Threshold in Heart Failure Patients With Atrial Fibrillation.

J Cardiopulm Rehabil Prev 2016 May-Jun;36(3):174-9

Centro Cardiologico Monzino (Drs Palermo, Stefanini, Agalbato, Compagnino, Maffessanti, and Agostoni), IRCCS, Milan, Italy; Dipartimento di Medicina Clinica e Molecolare (Dr Magrì), Università degli Studi di Roma "La Sapienza," Rome, Italy; Dipartimento di Scienze Cardiovascolari (Dr Sciomer), Respiratorie, Anestesiologiche, Nefrologiche e Geriatriche, "La Sapienza," Rome, Italy; Emergency Clinical Hospital Sibiu (Dr Chircu), Sibiu, Romania; Faculty of Medicine (Dr Teodoru), "Lucian Blaga" University, Sibiu, Romania; and Department of Clinical Sciences and Community Health (Dr Agostoni), University of Milan, Milan, Italy.

Purpose: To assess whether atrial fibrillation (AF) in heart failure (HF) affects oxygen uptake at anaerobic threshold ((Equation is included in full-text article.)O2 AT) and heart rate (HR) kinetics.

Methods: A total of 15 patients with HF and AF and 18 with HF and sinus rhythm (SR) performed a maximal incremental and 2 constant workload cycle ergometer cardiopulmonary exercise tests (below and above AT, at 25% and 75% of maximal workload, respectively). At constant workload tests, kinetics of (Equation is included in full-text article.)O2 and HR were assessed by calculating time constant (τ).

Results: HF patients with AF showed a similar peak (Equation is included in full-text article.)O2 to those with SR (16.7 ± 4.5 mL/kg/min vs 16.6 ± 3.9 mL/kg/min). However, (Equation is included in full-text article.)O2 AT (11.3 ± 2.9 mL/kg/min vs 9.3 ± 2.8 mL/kg/min; P < .05), peak HR (149 ± 18.8 bpm vs 116.4 ± 20.4 bpm; P < .001), HR AT (125.3 ± 19.1 bpm vs 90.3 ± 15.5 bpm; P < .001), and HR increase during exercise were greater in HF patients with AF. Finally, τHR and τ(Equation is included in full-text article.)O2 below and above AT were not significantly different.

Conclusions: In HF patients with AF, despite a similar peak (Equation is included in full-text article.)O2 compared with patients with HF and SR, (Equation is included in full-text article.)O2 AT is higher because of a higher HR and a greater HR increase during exercise. One postulated mechanism would be a greater cardiac output increase at the beginning of exercise in HF patients with AF. The delayed AT generates uncertainty about the meaning of a (Equation is included in full-text article.)O2 value at AT in HF patients with AF, because a higher AT is usually associated with better performance and a better prognosis.
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http://dx.doi.org/10.1097/HCR.0000000000000159DOI Listing
December 2017

Simultaneous Longitudinal Strain in All 4 Cardiac Chambers: A Novel Method for Comprehensive Functional Assessment of the Heart.

Circ Cardiovasc Imaging 2016 Mar;9(3):e003895

From the Department of Medicine, Section of Cardiology, University of Chicago, IL (K.A., F.M., V.M.-A., R.M.L.); School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan (M.T., Y.N.); and Epsilon Imaging, Ann Arbor, MI (J.H.).

Background: Simultaneous assessment of longitudinal strain (LS) by 2D speckle-tracking echocardiography in all 4 cardiac chambers has not yet been explored. Our goal was to study LS curves obtained simultaneously from all 4 cardiac chambers in healthy subjects to gain insight into interchamber functional relationships.

Methods And Results: We studied 259 healthy subjects (age 44±15; 118 men) in whom it was possible to obtain apical 4-chamber views that contained the entire left and right ventricles and both atria in the same sector. 2D speckle-tracking echocardiography was performed in all 4 chambers in the same cardiac cycle, while considering the interventricular septum as part of the left ventricle and including the interatrial septum in the LS measurements for both atria. LS was measured over time using vendor-independent software (Epsilon), resulting in peak LS and time-to-peak strain. Strain curves of the right ventricle and right atrium were larger in magnitude than those of the left ventricle and left atrium, whereas time-to-peak values were shorter. LS for the ventricles peaked earlier than the LS for the corresponding atria. Peak systolic LS values were larger in magnitude in women than in men. For both atria, LS declined with age and time-to-peak increased. Left ventricle LS declined minimally with age, but right ventricle free-wall LS augmented with age until the sixth decade.

Conclusions: Simultaneous measurement of LS provides new insights into interchamber relationships. This new tool may prove useful in evaluating diseases that affect cardiac chambers differently.
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http://dx.doi.org/10.1161/CIRCIMAGING.115.003895DOI Listing
March 2016

Prognosis of Myocardial Damage in Sarcoidosis Patients With Preserved Left Ventricular Ejection Fraction: Risk Stratification Using Cardiovascular Magnetic Resonance.

Circ Cardiovasc Imaging 2016 Jan;9(1):e003738

From the Departments of Medicine (G.M., L.J.L., F.M., C.A.B., A.V.P., Z.Y., K.A., V.M.-A., J.D.M., D.K.H., R.M.L., A.R.P.) and Radiology (R.M.L., A.R.P.), University of Chicago, IL; Department of Medicine, Mayo Clinic, Phoenix, AZ (J.F.B.); and Department of Medicine, University of Illinois at Chicago (N.J.S.).

Background: Cardiac sarcoidosis is associated with an increased risk of heart failure and sudden death, but its risk in patients with preserved left ventricular ejection fraction is unknown. Using cardiovascular magnetic resonance in patients with extracardiac sarcoidosis and preserved left ventricular ejection fraction, we sought to (1) determine the prevalence of cardiac sarcoidosis or associated myocardial damage, defined by the presence of late gadolinium enhancement (LGE), (2) quantify their risk of death/ventricular tachycardia (VT), and (3) identify imaging-based covariates that predict who is at greatest risk of death/VT.

Methods And Results: Parameters of left and right ventricular function and LGE burden were measured in 205 patients with left ventricular ejection fraction >50% and extracardiac sarcoidosis who underwent cardiovascular magnetic resonance for LGE evaluation. The association between covariates and death/VT in the entire group and within the LGE+ group was determined using Cox proportional hazard models and time-dependent receiver-operator curves analysis. Forty-one of 205 patients (20%) had LGE; 12 of 205 (6%) died or had VT during follow-up; of these, 10 (83%) were in the LGE+ group. In the LGE+ group (1) the rate of death/VT per year was >20× higher than LGE- (4.9 versus 0.2%, P<0.01); (2) death/VT were associated with a greater burden of LGE (14±11 versus 5±5%, P<0.01) and right ventricular dysfunction (right ventricular EF 45±12 versus 53±28%, P=0.04). LGE burden was the best predictor of death/VT (area under the receiver-operating characteristics curve, 0.80); for every 1% increase of LGE burden, the hazard of death/VT increased by 8%.

Conclusions: Sarcoidosis patients with LGE are at significant risk for death/VT, even with preserved left ventricular ejection fraction. Increased LGE burden and right ventricular dysfunction can identify LGE+ patients at highest risk of death/VT.
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http://dx.doi.org/10.1161/CIRCIMAGING.115.003738DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4718184PMC
January 2016

Three-dimensional echocardiography-based analysis of right ventricular shape in pulmonary arterial hypertension.

Eur Heart J Cardiovasc Imaging 2016 May 9;17(5):564-75. Epub 2015 Jul 9.

Department of Medicine, Section of Cardiology, University of Chicago, 5841 South Maryland Avenue, MC5084, Chicago, IL 60637, USA

Aims: Right ventricular (RV) remodelling involves changes in size, function, and shape. Although three-dimensional echocardiography (3DE) allows imaging of RV morphology, regional RV shape analysis has not been evaluated using 3DE. We developed a technique to quantify RV shape and tested its ability to differentiate normal from pressure overloaded right ventricles. Methods Transthoracic 3DE RV images were acquired in 54 subjects, including 39 patients with pulmonary artery hypertension (PAH) and 15 normal controls (NL). 3D RV surfaces were reconstructed (TomTec) at end-diastole and end-systole (ED, ES) and processed using custom software to calculate mean curvature of the inflow and outflow tracts (RVIT, RVOT), apex, and body (both divided into free wall and septum).

Methods And Results: Septal segments (apical and body) in NLs were characterized by concavity (curvature < 0) in ED and slight convexity (curvature > 0) in ES. In PAH, however, the septum remained convex, bulging into the left ventricle throughout the cardiac cycle. In keeping with the 'bellows-like' action of RV contraction in the NL group, the body free wall transitioned from a convex surface at ED to a more flattened surface at ES, while the apex free wall progressed from a less convex surface at ED to a more convex surface at ES. In contrast, in PAH, both RV free-wall segments (apical and body) remained equally convex throughout the cardiac cycle.

Conclusions: Curvature analysis using 3D echocardiography allows quantitative evaluation of RV remodelling, which could be used to track differential changes in regional RV shape, as a way to assess disease progression or regression.
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Source
http://dx.doi.org/10.1093/ehjci/jev171DOI Listing
May 2016