Publications by authors named "Mark F Aaron"

9 Publications

  • Page 1 of 1

Effects of exercise on left ventricular systolic and diastolic properties in patients with heart failure and a preserved ejection fraction versus heart failure and a reduced ejection fraction.

Circ Heart Fail 2013 May 20;6(3):508-16. Epub 2013 Mar 20.

Division of Cardiology, Medical University of South Carolina and RHJ Department of Veterans Affairs Medical Center, Charleston, SC 29425, USA.

Background: The purpose of the current study was to define exercise-induced changes in indices of left ventricular (LV) systolic and diastolic properties in patients with chronic heart failure (HF), compare these changes in patients with HF and a reduced ejection fraction (EF) versus HF and a preserved EF, and compare the hemodynamic responses to activities of daily living with symptom-limited upright exercise.

Methods And Results: Subjects with HF and a preserved EF (n=8) and subjects with HF and a reduced EF (n=5) underwent symptom-limited Naughton protocol treadmill exercise tests. Implantable hemodynamic monitor data and echocardiographic data were obtained before exercise and at peak exercise. Implantable hemodynamic monitor data were obtained during activities of daily living during a 24-hour time period. In patients with HF and a reduced EF, limited exercise time (639±164 seconds) was associated with a marked rise in right ventricular systolic, diastolic, and estimated pulmonary artery diastolic (ePAD) pressures and an increase in LV end diastolic volume (EDV). LV systolic properties, namely EF, end systolic elastance, stroke work, and preload recruitable stroke work, all decreased. The ePAD/EDV ratio increased; to a large extent, this was dependent on an increase in EDV. By contrast, in HF and a preserved EF, limited exercise time (411±128 seconds) and the marked rise in right ventricular systolic, diastolic, and ePAD pressures were associated with no change in LV EDV. LV systolic properties increased or were unchanged; ePAD/EDV ratio increased during exercise, but the increase was independent of a change in EDV. The ranges of right ventricular systolic, diastolic, and ePAD pressures during activities of daily living were higher than the ranges of these values during the exercise stress test.

Conclusions: Although exercise limitations were similar between HF and a reduced EF and HF and a preserved EF, there were significant differences in exercise-induced changes in LV systolic and diastolic properties. These differences likely reflect the different pathophysiologies of these clinical syndromes of HF.
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http://dx.doi.org/10.1161/CIRCHEARTFAILURE.112.000216DOI Listing
May 2013

Hemodynamic factors associated with acute decompensated heart failure: part 2--use in automated detection.

J Card Fail 2011 May 30;17(5):366-73. Epub 2011 Mar 30.

Oklahoma Foundation for Cardiovascular Research, Oklahoma Heart Hospital, Oklahoma City, OK, USA.

Background: The purpose of this study was to develop an automated surveillance system, using pressure-based hemodynamic factors that would detect which patients were making the transition from compensated to decompensated heart failure before they developed worsening symptoms and required acute medical care.

Methods And Results: Intracardiac pressures in 274 patients with heart failure were measured using an implantable hemodynamic monitor (IHM) and were analyzed in a retrospective manner. An automated pressure change detection (PCD) algorithm was developed using the cumulative sum method. The performance characteristics of the PCD algorithm were defined in all patients who developed a heart failure-related event (HFRE); patients without HFRE served as controls. Optimal PCD threshold values were chosen using a receiver operator curve analysis. Each of the pressures measured with the IHM were evaluated using the PCD analysis. All had sensitivities ≥80% and false-positive rates <4.7/patient-year; however, estimated pulmonary artery diastolic pressure (ePAD) had the best performance. An ePAD based on the optimized PCD threshold of 6.0 yielded a sensitivity of 83% and a false-positive rate of 4.1/patient-year for detecting patients making the transition from compensated to decompensated heart failure. These performance characteristics were not significantly different for patients with an ejection fraction > vs. <50%, estimated glomerular filtration rate > vs. <60 mL/min/1.73 m(2), or age > vs. <60 years.

Conclusions: The automated PCD algorithm had high sensitivity and acceptable false-positive rates in detecting the development of decompensated heart failure before the patient developed worsening symptoms and required acute medical care. These data support the development of a prospective study to examine the utility of adding an automated PCD algorithm to IHM-based management strategies to prevent decompensated heart failure.
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http://dx.doi.org/10.1016/j.cardfail.2011.01.011DOI Listing
May 2011

Hemodynamic factors associated with acute decompensated heart failure: part 1--insights into pathophysiology.

J Card Fail 2011 Apr 26;17(4):282-91. Epub 2011 Feb 26.

Division of Cardiology, Medical University of South Carolina, 25 Courtenay Drive, Charleston, SC 29425, USA.

Background: The purpose of this study was to determine which pressure-based hemodynamic factor was most closely associated with the transition from chronic compensated to acute decompensated heart failure.

Methods And Results: Intracardiac pressures were retrospectively examined in 274 heart failure patients using an implantable hemodynamic monitor. The relationship between the development of a heart failure-related event (HFRE) and 3 pressure variables were analyzed: peak estimated pulmonary artery diastolic pressure (ePAD) at the time of an HFRE, change in ePAD from baseline to peak pressure, and the product of ePAD pressure and time (P×T) calculated as the area under the pressure-versus-time curve from baseline to peak pressure. Patients without an HFRE served as control subjects. Peak ePAD and change in ePAD were not closely associated with the development of an HFRE. In patients with an HFRE, P×T was 221 ± 130 mm Hg·days with only 4% of the P×T values <60 mm Hg·days. In contrast, in patients without an HFRE, the P×T was 5 ± 23 with only 4% of the P×T values >60 mm Hg·days.

Conclusions: The product of small increases in pressure that occur over an extended period of time (P×T) is the pressure-based hemodynamic factor most closely associated with the transition to acute decompensated heart failure.
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http://dx.doi.org/10.1016/j.cardfail.2011.01.010DOI Listing
April 2011

Safety and accuracy of a wireless pulmonary artery pressure monitoring system in patients with heart failure.

Am Heart J 2011 Mar 31;161(3):558-66. Epub 2011 Jan 31.

The Ohio State University Heart Center, Columbus, USA.

Background: Implantable hemodynamic monitoring to guide heart failure (HF) therapy is a promising area of active research. The goal of this investigation was to evaluate the safety and technical performance of a novel wireless pulmonary artery pressure monitoring system in 17 patients with symptomatic HF.

Methods: The monitoring system consists of a sensor, delivery catheter, interrogator, and home monitoring device. The HF sensor was implanted into a distal branch of the pulmonary artery. Pulmonary artery pressures were monitored using the external device, which powers the HF sensor and transmits the hemodynamic data from the patient's home to a secure Internet database. The accuracy of the system was assessed by comparison with standard right heart catheterization (RHC).

Results: The HF sensor was safely and successfully implanted in all patients. Agreement between the HF sensor and RHC for systolic, diastolic, and mean pulmonary artery pressures was excellent, with correlation coefficients of 0.94, 0.85, and 0.95, respectively (all P < .0001). Using Bland-Altman plots, the average differences for systolic, diastolic, and mean pulmonary artery pressures for the HF sensor vs RHC were -4.4 ± 0.3, 2.5 ± 1.0, and -0.8 ± 1.3 mm Hg, respectively. There were no serious device-related adverse events. A postmortem analysis of the HF sensor in a patient who died 12 months after implant demonstrated complete endothelialization and no evidence of thrombosis.

Conclusions: This trial supports the safety and accuracy of this pulmonary artery pressure monitoring system in patients with HF and the conduct of randomized trials of implantable hemodynamic monitoring in HF, using this system.
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http://dx.doi.org/10.1016/j.ahj.2010.10.041DOI Listing
March 2011

Wireless pulmonary artery haemodynamic monitoring in chronic heart failure: a randomised controlled trial.

Lancet 2011 Feb;377(9766):658-66

Ohio State University Heart and Vascular Center, Columbus, OH, USA.

Background: Results of previous studies support the hypothesis that implantable haemodynamic monitoring systems might reduce rates of hospitalisation in patients with heart failure. We undertook a single-blind trial to assess this approach.

Methods: Patients with New York Heart Association (NYHA) class III heart failure, irrespective of the left ventricular ejection fraction, and a previous hospital admission for heart failure were enrolled in 64 centres in the USA. They were randomly assigned by use of a centralised electronic system to management with a wireless implantable haemodynamic monitoring (W-IHM) system (treatment group) or to a control group for at least 6 months. Only patients were masked to their assignment group. In the treatment group, clinicians used daily measurement of pulmonary artery pressures in addition to standard of care versus standard of care alone in the control group. The primary efficacy endpoint was the rate of heart-failure-related hospitalisations at 6 months. The safety endpoints assessed at 6 months were freedom from device-related or system-related complications (DSRC) and freedom from pressure-sensor failures. All analyses were by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00531661.

Findings: In 6 months, 83 heart-failure-related hospitalisations were reported in the treatment group (n=270) compared with 120 in the control group (n=280; rate 0·31 vs 0·44, hazard ratio [HR] 0·70, 95% CI 0·60-0·84, p<0·0001). During the entire follow-up (mean 15 months [SD 7]), the treatment group had a 39% reduction in heart-failure-related hospitalisation compared with the control group (153 vs 253, HR 0·64, 95% CI 0·55-0·75; p<0·0001). Eight patients had DSRC and overall freedom from DSRC was 98·6% (97·3-99·4) compared with a prespecified performance criterion of 80% (p<0·0001); and overall freedom from pressure-sensor failures was 100% (99·3-100·0).

Interpretation: Our results are consistent with, and extend, previous findings by definitively showing a significant and large reduction in hospitalisation for patients with NYHA class III heart failure who were managed with a wireless implantable haemodynamic monitoring system. The addition of information about pulmonary artery pressure to clinical signs and symptoms allows for improved heart failure management.

Funding: CardioMEMS.
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http://dx.doi.org/10.1016/S0140-6736(11)60101-3DOI Listing
February 2011

Application of implantable hemodynamic monitoring in the management of patients with diastolic heart failure: a subgroup analysis of the COMPASS-HF trial.

J Card Fail 2008 Dec 6;14(10):816-23. Epub 2008 Sep 6.

Division of Cardiology, Departmentof Medicine, Medical University of South Carolina and RHJ Department of Veterans Affairs Medical Center, Charleston, SC 29425, USA.

Background: Nearly half of all patients with chronic heart failure (HF) have a normal ejection fraction (EF), and abnormal diastolic function (ie, diastolic heart failure [DHF]). However, appropriate management of DHF patients remains a difficult and uncertain challenge.

Methods And Results: The Chronicle Offers Management to Patients with Advanced Signs and Symptoms of Heart Failure (COMPASS-HF) trial was designed to evaluate whether an implantable hemodynamic monitor (IHM) was safe and effective in reducing the number of heart failure-related events (HFRE) in patients with chronic HF. The current study presents data on a prespecified and planned subgroup analysis from the COMPASS-HF trial: 70 patients with an EF > or =50% (ie, DHF). As such, this represents a subgroup analysis of the COMPASS-HF Trial. DHF patients were randomized to IHM-guided care (treatment) vs. standard care (control) for 6 months. All 70 patients received optimal medical therapy, but the hemodynamic information from the IHM was used to guide patient management only in the treatment group. The HFRE rate in DHF patients randomized to treatment was 0.58 events/6 months compared with DHF patients randomized to control, which was 0.73 events/6 months; this represented a 20% nonsignificant reduction in the overall HFRE rate in the treatment group (95% CI = -46, 56, P = .66). There was a 29% nonsignificant reduction in the relative risk of a HF hospitalization in the DHF patients randomized to treatment compared with DHF patients randomized to control (95% CI = -69, 70, P = .43).

Conclusions: The IHM was shown to be safe and was associated with a very low system-related and procedure-related complication rate in DHF patients. However, in this subgroup analysis limited to 70 DHF patients, the addition IHM-guided care did not significantly lower the rate of HFR events. The results of this subgroup analysis in DHF patients, for whom there are currently no proven, effective management strategies, will be used to design future studies defining the effects of IHM-guided care in patients with DHF.
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http://dx.doi.org/10.1016/j.cardfail.2008.07.235DOI Listing
December 2008

Transition from chronic compensated to acute decompensated heart failure: pathophysiological insights obtained from continuous monitoring of intracardiac pressures.

Circulation 2008 Sep 15;118(14):1433-41. Epub 2008 Sep 15.

Department of Medicine, Division of Cardiology, Medical University of South Carolina, Charleston, SC 29425, USA.

Background: Approximately half of all patients with chronic heart failure (HF) have a decreased ejection fraction (EF) (systolic HF [SHF]); the other half have HF with a normal EF (diastolic HF [DHF]). However, the underlying pathophysiological differences between DHF and SHF patients are incompletely defined. The purpose of this study was to use echocardiographic and implantable hemodynamic monitor data to examine the pathophysiology of chronic compensated and acute decompensated HF in SHF versus DHF patients.

Methods And Results: Patients were divided into 2 subgroups: 204 had EF <50% (SHF) and 70 had EF >or=50% (DHF). DHF patients had EF of 58+/-8%, end-diastolic dimension of 50+/-10 mm, estimated resting pulmonary artery diastolic pressure (ePAD) of 16+/-9 mm Hg, and diastolic distensibility index (ratio of ePAD to end-diastolic volume) of 0.11+/-0.06 mm Hg/mL. In contrast, SHF patients had EF of 24+/-10%, end-diastolic dimension of 68+/-11 mm, ePAD of 18+/-7 mm Hg, and diastolic distensibility index of 0.06+/-0.04 mm Hg/mL (P<0.05 versus DHF for all variables except ePAD). In SHF and DHF patients who developed acute decompensated HF, these events were associated with a significant increase in ePAD, from 17+/-7 to 22+/-7 mm Hg (P<0.05) in DHF and from 21+/-9 to 24+/-8 mm Hg (P<0.05) in SHF. As a group, patients who did not have acute decompensated HF events had no significant changes in ePAD.

Conclusions: Significant structural and functional differences were found between patients with SHF and those with DHF; however, elevated diastolic pressures play a pivotal role in the underlying pathophysiology of chronic compensated and acute decompensated HF in both SHF and DHF.
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http://dx.doi.org/10.1161/CIRCULATIONAHA.108.783910DOI Listing
September 2008

Randomized controlled trial of an implantable continuous hemodynamic monitor in patients with advanced heart failure: the COMPASS-HF study.

J Am Coll Cardiol 2008 Mar;51(11):1073-9

Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA.

Objectives: The purpose of this study was to determine whether a heart failure (HF) management strategy using continuous intracardiac pressure monitoring could decrease HF morbidity.

Background: Patients with HF may experience frequent decompensations that require hospitalization despite intensive treatment and follow-up.

Methods: The COMPASS-HF (Chronicle Offers Management to Patients with Advanced Signs and Symptoms of Heart Failure) study was a prospective, multicenter, randomized, single-blind, parallel-controlled trial of 274 New York Heart Association functional class III or IV HF patients who received an implantable continuous hemodynamic monitor. Patients were randomized to a Chronicle (Medtronic Inc., Minneapolis, Minnesota) (n = 134) or control (n = 140) group. All patients received optimal medical therapy, but the hemodynamic information from the monitor was used to guide patient management only in the Chronicle group. Primary end points included freedom from system-related complications, freedom from pressure-sensor failure, and reduction in the rate of HF-related events (hospitalizations and emergency or urgent care visits requiring intravenous therapy).

Results: The 2 safety end points were met with no pressure-sensor failures and system-related complications in only 8% of the 277 patients who underwent implantation (all but 4 complications were successfully resolved). The primary efficacy end point was not met because the Chronicle group had a nonsignificant 21% lower rate of all HF-related events compared with the control group (p = 0.33). A retrospective analysis of the time to first HF hospitalization showed a 36% reduction (p = 0.03) in the relative risk of a HF-related hospitalization in the Chronicle group.

Conclusions: The implantable continuous hemodynamic monitor-guided care did not significantly reduce total HF-related events compared with optimal medical management. Additional trials will be necessary to establish the clinical benefit of implantable continuous hemodynamic monitor-guided care in patients with advanced HF.
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http://dx.doi.org/10.1016/j.jacc.2007.10.061DOI Listing
March 2008

Reducing events in patients with chronic heart failure (REDUCEhf ) study design: continuous hemodynamic monitoring with an implantable defibrillator.

Clin Cardiol 2007 Nov;30(11):567-75

The Heart Failure Institute at Oklahoma Heart Hospital, Oklahoma Foundation for Cardiovascular Research, Oklahoma City, Oklahoma USA.

Background: The use of implantable cardioverter defibrillators (ICDs) has been proven effective in the prevention of sudden cardiac death (SCD) and constitutes standard of care in appropriate populations. Combining a pressure sensing system with ICD therapy represents the first attempt to provide continuous hemodynamic monitoring using a device previously designed exclusively for SCD protection.

Methods: REDUCE is a prospective, multicenter, randomized, single-blind, parallel-controlled trial designed to assess the safety of the Chronicle ICD system (single chamber ICD with a hemodynamic monitoring system) and the effectiveness of a management strategy guided by intracardiac pressure information among ICD-indicated New York Heart Association (NYHA) Class II or III heart failure (HF) patients. Those successfully implanted with a Chronicle ICD will be randomized to the Chronicle group or Control group. All patients will receive optimal medical therapy, but the hemodynamic information from the device will be used to guide patient management only in the Chronicle group. Primary endpoints include freedom from system-related complications and relative risk reduction of one or more HF-related events (hospitalizations, and emergency department and urgent care visits requiring intravenous therapy for HF). Approximately 850 patients will be enrolled in at least 75 centers in the United States to accrue the 419 events needed to test the primary effectiveness endpoint. Enrollment began in April 2006, and is expected to end during 2009.

Conclusion: REDUCE will assess the safety of the Chronicle ICD system and the effectiveness of a patient management strategy based on remote access to continuous intracardiac pressures in reducing HF-related events.
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http://dx.doi.org/10.1002/clc.20250DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6653489PMC
November 2007
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