Publications by authors named "Daniel Zimpfer"

170 Publications

Propensity score-based analysis of long-term follow-up in patients supported with durable centrifugal left ventricular assist devices: the EUROMACS analysis.

Eur J Cardiothorac Surg 2021 Apr 19. Epub 2021 Apr 19.

Department of Cardiovascular Surgery, Institute for Clinical and Experimental Medicine, Prague, Czech Republic.

Objectives: The HeartWare HVAD (HW) and the HeartMate3 (HM3) are presently the most commonly used continuous-flow left ventricular assist devices worldwide. We compared the outcomes of patients supported with either of these 2 devices based on data from the EUROMACS (European Registry for Patients with Mechanical Circulatory Support).

Methods: A retrospective analysis of the survival and complications profile in propensity score-matched adult patients enrolled in the EUROMACS between 01 January 2016 and 01 September 2020 and supported with either an HW or HM3. Matching included demographic parameters, severity of cardiogenic shock and risk-modifying end-organ parameters that impact long-term survival. Survival on device and major postoperative adverse events were analysed.

Results: Following 1:1 propensity score matching, each group consisted of 361 patients. Patients were well balanced (<0.1 standardized mean difference). The median follow-up was similar in both groups [396 (interquartile range (IQR) 112-771) days for HW and 376 (IQR 100-816) days for HM3]. The 2-year survival was similar in both groups [HW: 61% 95% confidence interval (CI) (56-67%) vs HM3: 68% 95% CI (63-73%) (stratified hazard ratio for mortality: 1.13 95% CI (0.83-1.54), P = 0.435].The cumulative incidence for combined major adverse events and unexpected readmissions was similar in both groups [subdistribution hazard ratio (SHR) 1.0 (0.84-1.21), P = 0.96]. Patients in the HW group demonstrated a higher risk of device malfunction [SHR 2.44 (1.45-3.71), P < 0.001], neurological dysfunction [SHR 1.29 (1.02-1.61), P = 0.032] and intracranial bleeding [SHR 1.76 (1.13-2.70), P = 0.012].

Conclusions: Mid-term survival in both groups was similar in a propensity-matched analysis. The risk of device malfunction, neurological dysfunction and intracranial bleeding was significantly higher in HW patients.
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http://dx.doi.org/10.1093/ejcts/ezab144DOI Listing
April 2021

Concomitant cardiac surgery procedures during left ventricular assist device implantation: single-centre experience.

Ann Cardiothorac Surg 2021 Mar;10(2):248-254

Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria.

Background: Additional cardiac pathologies including tricuspid or mitral valve regurgitation are common in left ventricular assist device (LVAD) recipients and whether to address them remains controversial. We present our institutional outcomes of concomitant cardiac procedures, other than temporary right ventricular (RV) support, at the time of LVAD implantation.

Methods: From 03/2006 to 06/2020, 352 adult patients {median age 60 [interquartile range (IQR): 52-66] years; INTERMACS level 1 29%; INTERMACS level 2 17%; INTERMACS level 3 23%, INTERMACS level 4-6 31%; male 86%} underwent continuous-flow LVAD [Medtronic HVAD (HVAD) 50%; Abbott HeartMate II (HMII) 17%; Abbott HeartMate 3 (HM3) 33%] implantation. Concomitant valvular procedures were performed in 86 patients (24%) and the majority of patients received the LVAD as bridge to candidacy (BTC) for transplant (74%). Primary study endpoints were short- and mid-term mortality, as well as need for temporary RV support.

Results: Tricuspid valve annuloplasty was the most frequent concomitant procedure (77%), followed by aortic valve replacements (AVRs) or Park's stitch (33%). Temporary RV support was common in the study cohort (35%) using either extracorporeal life support (ECLS, 37%) or a temporary RV assist device (RVAD, 63%). A less invasive (LIS) implantation technique was pursued in 12%. Thirty-day mortality was comparable between those with and without concomitant surgery (4% 6%, P=0.426). In-hospital mortality was significantly higher for additional interventions (22% 14%, P=0.05), whereas one-year survival was similar (71% 79%, P=0.106).

Conclusions: Concomitant cardiac procedures, especially tricuspid and aortic valve surgery, are frequent but are associated with a higher perioperative morbidity and mortality.
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http://dx.doi.org/10.21037/acs-2020-cfmcs-30DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8033261PMC
March 2021

The left ventricular assist device as a patient monitoring system.

Ann Cardiothorac Surg 2021 Mar;10(2):221-232

Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.

Technological progress of left ventricular assist devices (LVADs) towards rotary blood pumps and the optimization of medical management contributed to the significant improvements in patient survival as well as LVAD support duration. Even though LVAD therapy is now well-established for end-stage heart failure patients, the long-term occurrence of adverse events (AE) such as bleeding, infection or stroke, still represent a relevant burden. An early detection of AE, before onset of major symptoms, can lead to further optimization of patient treatment and thus mitigate the burden of AE. Continuous patient monitoring facilitates identification of pathophysiological states and allows anticipation of AE to improve patient management. In this paper, methods, algorithms and possibilities for continuous patient monitoring based on LVAD data are reviewed. While experience with continuous LVAD monitoring is currently limited to a few centers worldwide, the pace of developments in this field is fast and we expect these technologies to have a global impact on the well-being of LVAD patients.
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http://dx.doi.org/10.21037/acs-2020-cfmcs-218DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8033254PMC
March 2021

Ticagrelor or aspirin after coronary artery bypass in patients with chronic kidney disease.

Ann Thorac Surg 2021 Apr 2. Epub 2021 Apr 2.

Deutsches Herzzentrum Mu¨nchen, Technische Universität Mu¨nchen, Germany; German Center for Cardiovascular Research (DZHK), Munich Heart Alliance, Germany.

Background: The optimal antiplatelet therapy for patients with chronic kidney disease (CKD) undergoing coronary artery bypass grafting (CABG) remains unknown.

Methods: This post hoc analysis of the Ticagrelor in Coronary Artery Bypass (TiCAB) trial examined the efficacy and safety of ticagrelor versus aspirin in patients with or without CKD. Primary endpoint was the composite of cardiovascular death, stroke, myocardial infarction or revascularization (MACCE) at 1 year after CABG. Secondary endpoints included individual components of the primary endpoint, all-cause death, and major bleeding.

Results: CKD was present in 276 of 1,843 randomized patients (15.0%). Patients with CKD versus those without CKD had higher 1-year rates of MACCE (13.0% vs. 8.3%, HR 1.63, 95% CI 1.12-2.39, P=0.01) and major bleeding (5.6% vs. 3.1%, HR 1.84, 95% CI 1.03-3.28, P=0.04). The 1-year rate of MACCE was increased with ticagrelor versus aspirin in patients with CKD (18.2% vs. 8.9%, HR 2.15, 95% CI 1.08-4.30, P=0.03), but not in patients without CKD (8.5% vs. 8.1%, HR 1.05, 95% CI 0.74-1.49, P=0.79) (P=0.067). There was no difference in the 1-year rate of major bleeding with ticagrelor versus aspirin in patients with CKD (6.6% vs. 4.7%, HR 1.44, 95% CI 0.52-3.97, P=0.48) and without CKD (3.3% vs. 2.9%, HR 1.14, 95% CI 0.64-2.01, P=0.65).

Conclusions: In patients with CKD and CABG, those who received ticagrelor had a higher incidence of MACCE but a similar incidence of major bleeding compared to those who received aspirin.
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http://dx.doi.org/10.1016/j.athoracsur.2021.03.061DOI Listing
April 2021

Platelet activation and aggregation in different centrifugal-flow left ventricular assist devices.

Platelets 2021 Mar 24:1-8. Epub 2021 Mar 24.

Department of Internal Medicine II, Medical University of Vienna, Vienna, Austria.

Left-ventricular assist devices (LVADs) improve outcomes in end-stage heart failure patients. Two centrifugal-flow LVAD systems are currently approved, HeartMate 3 (HM3) and Medtronic/Heartware HVAD (HVAD). Clinical findings suggest differences in thrombogenicity between both systems. We compared markers of platelet activation and aggregation between HM3 and HVAD. We prospectively included 59 LVAD patients (40 HM3, 19 HVAD). Platelet -selectin expression, activated glycoprotein (GP) IIb/IIIa and monocyte-platelet aggregates (MPA) were assessed by flow-cytometry. Platelet aggregation was measured by light-transmission aggregometry (LTA) and multiple-electrode aggregometry (MEA). Von-Willebrand factor (VWF) antigen (VWF:Ag), VWF activity (VWF:Ac), and VWF multimer pattern analysis were determined. Soluble -selectin (sP-selectin) was measured with an enzyme-linked immunoassay. -selectin, GPIIb/IIIa and MPA levels and in response to arachidonic acid, adenosine diphosphate, and thrombin receptor activating peptide were similar between HM3 and HVAD (all > .05). Likewise, agonist-inducible platelet aggregation by LTA and MEA did not differ between HM3 and HVAD (all > .05). VWF:Ag levels and FVIII:C were similar between both systems (both > .05), but patients with HVAD had significantly lower VWF:Ac ( = .011) and reduced large VWF multimers ( = .013). Finally, sP-selectin levels were similar in patients with HVAD and HM3 ( = .845). In conclusion, on-treatment platelet activation and aggregation are similar in HM3 and HVAD patients. Potential clinical implications of observed differences in VWF profiles between both LVAD systems need to be addressed in future clinical trials.
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http://dx.doi.org/10.1080/09537104.2021.1881950DOI Listing
March 2021

Successful surgical treatment of a 1160 g neonate with cardiac teratoma and severe foetal hydrops: a case report.

Eur Heart J Case Rep 2021 Feb 4;5(2):ytaa527. Epub 2021 Jan 4.

Department of Surgery, Division of Cardiac Surgery, Medical University of Vienna, Austria.

Background: Prenatally diagnosed pericardial teratoma present a rare finding with an unfavourable prognosis due to frequently associated Foetal hydrops and limited treatment options. We report a successful surgical resection of a prenatally diagnosed cardiac teratoma in a 1160 g neonate with severe Foetal hydrops and cardiac deterioration.

Case Summary: The patient was transferred in utero to our institution due to prior diagnosed pericardial mass and severe foetal hydrops, which necessitated caesarean section one day after arrival at a gestational age of 28 + 0 weeks. After intubation, the patient was stabilized by surgical drainage of 60 mL of pericardial effusion. Further clinical worsening of the patient on the day of life 12 demanded urgent intervention, so that in toto resection of the tumour was performed at a bodyweight of 1160 g. Histopathological analysis revealed a teratoma and the patient is in excellent clinical condition one year after surgery.

Discussion: This case report demonstrates that an interdisciplinary, two-staged approach can be a feasible and promising treatment option in patients with prenatally diagnosed teratoma and severe Foetal hydrops in a critical circulatory state. Furthermore, it illustrated that resection of pericardial masses can be successfully performed at a bodyweight as low as 1160 g.
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http://dx.doi.org/10.1093/ehjcr/ytaa527DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7954248PMC
February 2021

Implanting the HeartMate 6 (total artificial heart).

Multimed Man Cardiothorac Surg 2021 03 2;2021. Epub 2021 Mar 2.

Department of Cardiac Surgery, Medical University of Vienna, Austria

The HeartMate 3 is a ventricular assist device that supports the heart with a centrifugal continuous flow. It contains a fully levitated rotor to minimize hemolysis and was initially designed as an apical intrapericardial implant. It can be used as a bridge to a transplant, to recovery, or to destination therapy. After we excise the ventricles, we implant 2 HeartMate 3 devices as a total artificial heart (HeartMate 6). The patient was 35 years old when the devices were implanted and had been diagnosed with Yamaguchi syndrome (apical hypertrophic cardiomyopathy) at 13 years of age. Being listed for a transplant was not an option due to secondary pulmonary hypertension. Furthermore, the conventional method of apically implanting a left ventricular assist device was not possible due to the underlying pathology. A HeartMate 6 implant as a bridge to transplant therapy was planned. Additionally, a CardioMEMS HF System was implanted to monitor the pulmonary artery pressure. The video tutorial provides step-by-step instructions for implanting 2 HeartMate 3 devices as a total artificial heart.
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http://dx.doi.org/10.1510/mmcts.2021.012DOI Listing
March 2021

Diagnostic quality of 3Tesla postmortem magnetic resonance imaging in fetuses with and without congenital heart disease.

Am J Obstet Gynecol 2021 Mar 1. Epub 2021 Mar 1.

Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.

Background: Postmortem confirmation of prenatally diagnosed congenital heart disease after termination of pregnancy and evaluation of potential cardiac defects after spontaneous fetal or neonatal death are essential. Conventional autopsy rates are decreasing, and 1.5Tesla magnetic resonance imaging has demonstrated limited diagnostic accuracy for postmortem cardiovascular assessment.

Objective: This study aimed to evaluate the feasibility and image quality of cardiac 3Tesla postmortem magnetic resonance imaging and to assess its diagnostic accuracy in detecting fetal heart defects compared with conventional autopsy. Secondarily, the study aimed to explore whether clinical factors affect the quality of 3Tesla postmortem magnetic resonance imaging.

Study Design: A total of 222 consecutive fetuses between 12 and 41 weeks' gestation, who underwent 3Tesla postmortem magnetic resonance imaging and conventional autopsy after spontaneous death or termination of pregnancy for fetal malformations, were included. First, 3Tesla postmortem magnetic resonance imaging of each fetus was rated as diagnostic or nondiagnostic for fetal cardiac assessment by 2 independent raters. The image quality of individual cardiac structures was then further evaluated by visual grading analysis. Finally, the presence or absence of a congenital heart defect was assessed by 2 radiologists and compared with autopsy results.

Results: Overall, 87.8% of 3Tesla postmortem magnetic resonance imaging examinations were rated as diagnostic for the fetal heart. Diagnostic imaging rates of individual cardiac structures at 3Tesla postmortem magnetic resonance imaging ranged from 85.1% (atrioventricular valves) to 94.6% (pericardium), with an interrater agreement of 0.82 (0.78-0.86). Diagnostic imaging of the fetal aortic arch and the systemic veins at 3Tesla postmortem magnetic resonance imaging was possible from 12+5 weeks' gestation onward in 90.1% and 92.3% of cases, respectively. A total of 55 fetuses (24.8%) had at least 1 cardiac anomaly according to autopsy, 164 (73.9%) had a normal heart, and in 3 fetuses (1.4%), autopsy was nondiagnostic for the heart. Considering all examinations rated as diagnostic, 3Tesla postmortem magnetic resonance imaging provided high diagnostic accuracy for the detection of fetal congenital heart defects with a sensitivity of 87.8%, a specificity of 97.9%, and concordance with autopsy of 95.3%. 3Tesla postmortem magnetic resonance imaging was less accurate in young fetuses (<20 weeks compared with ≥20 weeks; P<.001), in fetuses with low birthweight (≤100 g compared with >100 g; P<.001), in cases after spontaneous fetal death (compared with other modes of death; P=.012), in cases with increasing latency between death and 3Tesla postmortem magnetic resonance imaging (P<.001), and in cases in which there was a high degree of maceration (maceration score of 3 compared with a score from 0 to 2; P=.004).

Conclusion: Diagnostic 3Tesla postmortem magnetic resonance imaging assessment of the fetal heart is feasible in most fetuses from 12 weeks' gestation onward. In diagnostic images, sensitivity and, particularly, specificity in the detection of congenital heart disease are high compared with conventional autopsy. Owing to its high diagnostic accuracy, we suggest that 3Tesla postmortem magnetic resonance imaging may serve as a suitable imaging modality with which to direct a targeted conventional autopsy when pathology resources are limited or to provide a virtual autopsy when full autopsy is declined by the parents.
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http://dx.doi.org/10.1016/j.ajog.2021.02.030DOI Listing
March 2021

Impact of Less Invasive Left Ventricular Assist Device Implantation on Heart Transplant Outcomes.

Semin Thorac Cardiovasc Surg 2021 Feb 17. Epub 2021 Feb 17.

Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria; Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria. Electronic address:

Left ventricular assist device implantation without sternotomy (LIS) may simplify heart transplantation (HTX) by avoiding adhesions and eliminating the need for a re-sternotomy. This study investigates the impact of LIS LVAD implantation on HTX outcomes. A retrospective comparison of 46 patients undergoing HTX between 07/13 and 06/19 after conventional LVAD implantation with a full sternotomy (FS) and LIS LVAD implantation (LIS: n = 27 patients, 59%; FS: n = 19 patients, 41%) was performed. Endpoints were perioperative data including blood product use, de-novo formation of donor specific antibodies (DSAs) and survival. Patient demographics (mean age FS: 60.3 ± 9.3 years vs LIS 58.0 ± 7.7 years, P = 0.313; male gender FS: 84% vs LIS: 82%, P = 1.000; urgent HTX FS: 16% vs LIS 18%, P = 1.000) were comparable between LIS and FS patients. The primary finding was a significantly higher risk to develop de novo donor specific antibodies (DSAs) after HTX in patients of the FS group (FS: 36% vs LIS: 4%; P = 0.006). LIS patients had a significant reduction of intraoperative packed red blood cells (PRBCs) use (LIS: 4 (IQR 2-7) Units vs FS: 7 (IQR 4-8) Units; P = 0.045). Other adverse events rates and in-hospital mortality (LIS: 7% vs FS 5%, P = 1.000) were comparable between both groups. LIS LVAD reduces formation of donor specific antibodies after HTX.
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http://dx.doi.org/10.1053/j.semtcvs.2021.02.001DOI Listing
February 2021

Five-year outcomes of patients supported with HeartMate 3: a single-centre experience.

Eur J Cardiothorac Surg 2021 Feb 15. Epub 2021 Feb 15.

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

Objectives: The HeartMate 3 left ventricular assist device was first implanted in 2014 and received the Conformité Européenne mark in 2015. Since then, several trials demonstrated its high haemocompatibility associated with good survival and low adverse events rates. Herein, we report our institutional experience with patients supported with HeartMate 3 for 5 years.

Methods: This prospective cohort study included patients receiving a HeartMate 3 implantation in 2014 as part of the HeartMate 3 Conformité Européenne Mark clinical trial. Patients had follow-up visits every 3 months while on left ventricular assist device support, and all patients completed the 5-year follow-up. The primary end point was survival at 5 years. Secondary end points included adverse events, health status and quality of life.

Results: Eight patients (men: 75%) aged 59 years (min-max: 52-66 years) were enrolled. At 5 years, survival was 100%. Patients remained on support for a median time of 1825 days (min-max: 101-1825 days); 2 patients successfully received cardiac transplants. No right heart failure, haemolysis, pump thrombosis, pump malfunction or neurological events occurred in any patients. A driveline infection was observed in 6 patients (0.25 events/patient-year). Compared to baseline, a significant improvement in quality of life and in New York Heart Association functional class was noted after the implant and for the whole follow-up time. A slight decline in kidney function and in the 6-min walk test results occurred after 3 years.

Conclusions: This study reports the longest single-centre follow-up of the HeartMate 3, showing excellent haemocompatibility over time with high survival and low complication rates at 5 years.
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http://dx.doi.org/10.1093/ejcts/ezab018DOI Listing
February 2021

Impact of a surgical approach for implantation of durable left ventricular assist devices in patients on extracorporeal life support.

J Card Surg 2021 Apr 5;36(4):1344-1351. Epub 2021 Feb 5.

Department of Cardiac Surgery, Leipzig Heart Center, Leipzig, Germany.

Background: The aim of this study was to evaluate the impact of the surgical approach on the postoperative outcome in patients who underwent left ventricular assist device (LVAD) implantation after having received veno-arterial extracorporeal life support (va-ECLS) using data from a European registry (ECLS-VAD). Five hundred and thirty-one patients were included.

Methods: A propensity score-adjusted outcome analysis was performed, resulting in 324 patients in the full sternotomy (FS) group and 39 in the less invasive surgery (LIS) group.

Results: The surgery lasted in median 236 min in the FS group versus 263 min in the LIS group (p = 0.289). The median chest tube output during the first 24 h was similar in both groups. Patients who underwent implantation with an FS required more blood products during the first 24 postoperative hours (median 16 vs. 12, p = 0.033). The incidence of revision due to bleeding was also higher (35.5 vs. 15.4%, p = 0.016). A temporary postoperative right ventricular assist device was necessary in 45.1 (FS) versus 23.1% (LIS) of patients, respectively (p = 0.067). No stroke occurred in the LIS group during the first 30 days after surgery (7.4% in the FS group). The incidence of stroke and of renal, hepatic, and respiratory failure during the follow-up was similar in both groups. The 30-day and one-year survival were similar in both groups.

Conclusion: LIS for implantation of a durable LVAD in patients on va-ECLS implanted for cardiogenic shock is associated with less revision due to bleeding, less administration of blood products and absence of perioperative stroke, with no impact on survival.
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http://dx.doi.org/10.1111/jocs.15401DOI Listing
April 2021

First 5-year multicentric clinical trial experience with the HeartMate 3 left ventricular assist system.

J Heart Lung Transplant 2021 Apr 8;40(4):247-250. Epub 2021 Jan 8.

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

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http://dx.doi.org/10.1016/j.healun.2021.01.001DOI Listing
April 2021

Transition From Temporary to Durable Circulatory Support Systems.

J Am Coll Cardiol 2020 12;76(25):2956-2964

Department of Cardiovascular and Thoracic Surgery, Heart and Diabetes Center NRW, Bad Oeynhausen, Germany.

Background: The decision to implant durable mechanical circulatory systems (MCSs) in patients on extracorporeal life support (ECLS) is challenging due to expected poor outcomes in these patients.

Objectives: The aim of this study was to identify outcome predictors that may facilitate future patient selection and decision making.

Methods: The Durable MCS after ECLS registry is a multicenter retrospective study that gathered data on consecutive patients who underwent MCS implantation after ECLS between January 2010 and August 2018 in 11 high-volume European centers. Several perioperative parameters were collected. The primary endpoint was survival at 1 year after durable MCS implantation.

Results: A total of 531 durable MCSs after ECLS were implanted during this period. The average patient age was 53 ± 12 years old. ECLS cannulation was peripheral in 87% of patients and 33% of the patients had history of cardiopulmonary resuscitation before ECLS implantation. The 30-day, 1-year, and 3-year actuarial survival rates were 77%, 53%, and 43%, respectively. The following predictors for 1-year outcome have been observed: age, female sex, lactate value, Model of End-Stage Liver Disease XI score, history of atrial fibrillation, redo surgery, and body mass index >30 kg/m. On the basis of this data, a risk score and an app to estimate 1-year mortality was created.

Conclusions: The outcome in patients receiving durable MCS after ECLS remains limited, yet preoperative factors may allow differentiating futile patients from those with significant survival benefit.
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http://dx.doi.org/10.1016/j.jacc.2020.10.036DOI Listing
December 2020

Expert Consensus Paper: Lateral Thoracotomy for Centrifugal Ventricular Assist Device Implant.

Ann Thorac Surg 2020 Dec 9. Epub 2020 Dec 9.

Department of Cardiothoracic Surgery, Newark Beth Israel Medical Center, USA.

Background: The increasing prevalence of heart failure has led to the expanded use of left ventricle assist devices (VADs) for end-stage heart failure patients worldwide. Technological improvements witnessed the development of miniaturized VADs and their implantation through less traumatic "non-full sternotomy approaches" using a lateral thoracotomy (LT). Although adoption of the LT approach is steadily growing, there remains a lack of consensus regarding patient selection, details of the surgical technique, and perioperative management. Furthermore, the current literature does not offer prospective randomized studies or evidence-based guidelines for LT-VAD implantation.

Methods: A worldwide group of LT-VAD experts was convened to openly discuss these key topics. After a PubMed search and review with all authors, a consensus was reached and an expert consensus paper on LT-VAD implantation was developed.

Results: This document aims to guide clinicians in the selection of patients suitable for LT approaches and preoperative optimization. Details of operative techniques are described, with an overview of hemisternotomy and bilateral thoracotomy approaches. A review of the best surgical practices for placement of the pump, inflow cannula and outflow graft provides advice on the best surgical strategies to avoid device malpositioning while optimizing VAD function. Experts´ opinions on cardiopulmonary bypass, postoperative management, and approaches for pump exchange and explant are presented. This paper also emphasizes the critical need for multidisciplinary teams and specified training.

Conclusions: This expert consensus paper provides a compact guide to LT for VAD implantation, from patient selection through intraoperative tips and postoperative management.
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http://dx.doi.org/10.1016/j.athoracsur.2020.09.063DOI Listing
December 2020

Copeptin - prognostic relevance as a perioperative marker in pediatric cardiac surgery.

Ann Thorac Surg 2020 Dec 4. Epub 2020 Dec 4.

Department of Surgery, Division of Cardiac Surgery and Pediatric Heart Center, Medical University of Vienna, Austria. Electronic address:

Background: Copeptin is a cleavage product of vasopressin. This study aimed to figure out if copeptin would be a suitable biomarker in patients with congenital heart disease in the postoperative course.

Methods: The primary outcome endpoint of this study was the change in copeptin concentration perioperatively in patients with congenital heart disease after surgery, with the use of a cardiopulmonary bypass. Three blood samples were taken from 81 patients up to six years of age in order to evaluate changes in copeptin concentration.

Results: Significant increase of copeptin concentration was shown between the first and second as well as the first and third blood draw (p 's < .001). Additionally, positive and significant correlations (r ≥ .27) between the cardiopulmonary bypass times, the STS-EACTS (STAT) mortality category, the inotropic score, the duration of mechanical ventilation, the length of stay at the ICU, the length of stay at the hospital and the preoperative as well as the ICU copeptin levels were found.

Conclusions: Copeptin showed a tendency to predict the clinical outcome of patients after congenital heart surgery. Patients with higher copeptin levels, underwent more complex procedures, had longer cardiopulmonary bypass times, required more catecholamine support, needed longer time of invasive ventilation, and had a longer overall stay and ICU stay.
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http://dx.doi.org/10.1016/j.athoracsur.2020.11.017DOI Listing
December 2020

Two-year outcome after implantation of a full magnetically levitated left ventricular assist device: results from the ELEVATE Registry.

Eur Heart J 2020 10;41(39):3801-3809

University Department of Cardiac Surgery, Heart Center Leipzig, Leipzig, Germany.

Aims: The ELEVATE Registry was designed to study long-term outcomes with the Heartmate 3 (HM3), a fully magnetically levitated centrifugal ventricular assist device, in a real-world population following CE-mark approval.

Methods And Results: A total of 540 patients, implanted in Europe and the Middle East were followed in ELEVATE. The registry included 463 patients receiving the HM3 as primary implant (Primary Implant Cohort), 19 patients underwent a pump upgrade from another device (Pump Exchange Cohort) and 58 patients who had experienced an outcome before having the possibility to sign the Informed Consent, for which only outcome data were collected (Anonymized Cohort). Data collection included demographics, survival, adverse events, EQ-5D Visual Analog Score quality of life (EQ-5D VAS QOL) questionnaire, and 6-min walk distance (6MWD). Mean age was 55.6 ± 11.7 years (89% male, 48% ischaemic cardiomyopathy). Seventy per cent of patients were in INTERMACS Profile 1-3 and 12.7% were on temporary mechanical circulatory support. Primary Implant Cohort survival was 83% after 2 years. In the Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation Primary Implant Cohort, strokes were observed in 10.2%, gastrointestinal bleedings in 9.7%, pump thrombosis in 1.5%, and outflow graft twists in 3.5%. Heartmate 3 implantation resulted in a significant and sustained improvement of functional capacity and QOL.

Conclusion: In a real-world population, cohort implanted with the HM3 left ventricular assist device we demonstrate good long-term survival, sustained improvement of functional capacity, and low rates of adverse events (including pump thrombosis).

Clinicaltrials.gov Identifier: NCT02497950.
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http://dx.doi.org/10.1093/eurheartj/ehaa639DOI Listing
October 2020

Left ventricular assist device driveline infections in three contemporary devices.

Artif Organs 2021 May 28;45(5):464-472. Epub 2020 Nov 28.

Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.

Driveline infections (DLI) are common adverse events in left ventricular assist devices (LVADs), leading to severe complications and readmissions. The study aims to characterize risk factors for DLI readmission 2 years postimplant. This single-center study included 183 LVAD patients (43 HeartMate II [HMII], 29 HeartMate 3 [HM3], 111 HVAD) following hospital discharge between 2013 and 2017. Demographics, clinical parameters, and outcomes were retrospectively analyzed and 12.6% of patients were readmitted for DLI, 14.8% experienced DLI but were treated in the outpatient setting, and 72.7% had no DLI. Mean C-reactive protein (CRP), leukocytes and fibrinogen were higher in patients with DLI readmission (P < .02) than in outpatient DLI and patients without DLI, as early as 60 days before readmission. Freedom from DLI readmission was comparable for HMII and HVAD (98% vs. 87%; HR, 4.52; 95% CI, 0.58-35.02; P = .15) but significantly lower for HM3 (72%; HR, 10.82; 95% CI, 1.26-92.68; P = .03). DLI (HR, 1.001; 95% CI, 0.999-1.002; P = .16) or device type had no effect on mortality. DLI readmission remains a serious problem following LVAD implantation, where CRP, leukocytes, and fibrinogen might serve as risk factors already 60 days before. HM3 patients had a higher risk for DLI readmissions compared to HVAD or HMII, possibly because of device-specific driveline differences.
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http://dx.doi.org/10.1111/aor.13843DOI Listing
May 2021

Accuracy of Doppler blood pressure measurement in HeartMate 3 ventricular assist device patients.

ESC Heart Fail 2020 Oct 1. Epub 2020 Oct 1.

Division of Cardiology, Department of Medicine, University of Washington, Seattle, WA, 98195, USA.

Aims: Optimal blood pressure (BP) control is imperative to reduce complications, especially strokes, in continuous flow ventricular assist device (VAD) patients. Doppler BP has been shown to be an accurate and reliable non-invasive BP measurement method in HeartMate II and HVAD patients. We examined whether Doppler BP is also accurate in patients with the HeartMate 3 VAD.

Methods And Results: In a prospective, longitudinal cohort of HeartMate 3 patients, arterial line BP and simultaneously measured Doppler opening pressure were obtained. Correlation and agreement between Doppler opening pressure and arterial line mean arterial pressure (MAP) versus systolic blood pressure (SBP) were analysed, as well as the effect of pulse pressure on the accuracy of Doppler opening pressure. A total of 589 pairs of simultaneous Doppler opening pressure and arterial line pressure readings were obtained in 43 patients. Doppler opening pressure had good correlation with intra-arterial MAP (r = 0.754) and more closely approximated MAP than SBP (mean error 2.0 vs. -8.6 mmHg). Pulse pressure did not have a clinically significant impact on the accuracy of the Doppler BP method. These results in HeartMate 3 patients are very similar to previous results in HeartMate II and HVAD patients.

Conclusions: Doppler BP method should be the default non-invasive BP measurement method in continuous flow VAD patients including patients implanted with the HeartMate 3.
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http://dx.doi.org/10.1002/ehf2.13056DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7754743PMC
October 2020

Double atrioventricular valve replacement using Melody™ transcatheter valves in an infant with unbalanced atrioventricular septal defect: a case report.

Eur Heart J Case Rep 2020 Aug 5;4(4):1-6. Epub 2020 Aug 5.

Division of Cardiac Surgery, Pediatric Heart Center Vienna, Department of Surgery, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria.

Background: To the best of our knowledge, this is the first report of a successful one-stage double atrioventricular valve (AVV) replacement using two Melody™ transcatheter valves in an infant.

Case Summary: We report a successful case of double AVV replacement with Melody™ transcatheter valves in a 9-month-old infant with a right ventricular dominant atrioventricular septal defect (AVSD). The boy initially presented with borderline sized left-sided heart structures, congenital left AVV stenosis, ventricular displacement of the right AVV with high-grade insufficiency and moderate valvar pulmonary stenosis. Double AVV replacement was performed 2 months after an unsuccessful attempt to repair the defect with persisting left AVV stenosis, underfilling of the small left ventricle and high-grade right AVV, and pulmonary valve regurgitation, resulting in low cardiac output. During double Melody™ AVV replacement, the right ventricular outflow tract was replaced with a pulmonary homograft. The boy was discharged on post-operative Day 28 and presented with competent valves, no ventricular outflow tract obstruction and no paravalvular leak at 11 months of follow-up.

Discussion: The presented innovative approach allowed for biventricular correction of an unbalanced AVSD with unfavourable anatomy for standard techniques. The heart team should decide individualized, after careful assessment of cardiac anatomy and function, if the benefits of replacement of AVVs with Melody™ transcatheter valves may outweigh the benefits of univentricular palliation in case of unbalanced AVSD.
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http://dx.doi.org/10.1093/ehjcr/ytaa174DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7501891PMC
August 2020

Thrombolysis as first-line therapy for Medtronic/HeartWare HVAD left ventricular assist device thrombosis.

Eur J Cardiothorac Surg 2020 12;58(6):1182-1191

Department of Surgery, Division of Cardiac Surgery, Medical University of Vienna, Vienna, Austria.

Objectives: We reviewed our institutional experience with intravenous thrombolysis (TL) as first-line therapy in patients with Medtronic/HeartWare HVAD left ventricular assist device pump thrombosis (PT).

Methods: From March 2006 to November 2018, 30 Medtronic/HeartWare HVAD left ventricular assist device patients had 48 PT events. We analysed outcomes with intravenous Alteplase as a first-line therapy for PT. Pump exchange or urgent heart transplantation was only considered after the failure of TL or existing contraindications to TL.

Results: TL was used as the first-line therapy in 44 PT events in 28 patients without a contraindication to TL. TL was successful in 61.4% of PT events. More than 1 cycle of TL was necessary in 55.6% of events. The combined success of TL and heart transplantation or device exchange was 81.8%. In 15.9% of events, PT was fatal. Causes of death were severe complications (9.1%) related to TL or discontinuation of therapy for multi-organ failure (6.8%). Intracranial bleeding and arterial thromboembolism were observed in 4.5% and 11.5% of the PT events after TL.

Conclusions: Intravenous TL as a first-line therapy for PT in Medtronic/HeartWare HVAD patients can be a reasonable treatment option and does not preclude subsequent heart transplantation or device exchange. However, thromboembolic and bleeding complications are common. The decision to perform TL or device exchange should, therefore, be made on an individual basis after balancing the risks and benefits of different treatment approaches.
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http://dx.doi.org/10.1093/ejcts/ezaa180DOI Listing
December 2020

International experience using a durable, centrifugal-flow ventricular assist device for biventricular support.

J Heart Lung Transplant 2020 12 20;39(12):1372-1379. Epub 2020 Aug 20.

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

Background: Heart transplantation is limited by the scarcity of suitable donors. Patients with advanced biventricular failure may require biventricular support to provide optimal cardiac output and end-organ perfusion. We highlight the outcomes of using the HeartWare HVAD System (HVAD) in a biventricular configuration.

Methods: This retrospective study included patients implanted with HVAD as a biventricular assist device (BiVAD) between 2009 and 2017 at 12 participating centers. When used as a right ventricular assist device (VAD) (RVAD), the HVAD can be attached to the right ventricle (RV) or the right atrium (RA). Kaplan-Meier survival estimates were calculated comparing the 2 RVAD implant locations. Comparisons were also made between the timing of RVAD implantation (primary vs staged) on adverse event (AE) profiles and survival.

Results: Among the 93 patients who were implanted with a HVAD BiVAD, Kaplan-Meier survivals at 1-year and 2-year were 56% and 47%, respectively. Survival was independent of the location of the HVAD RVAD implant or whether there was an interval between left VAD and RVAD implantation. The most common AEs were bleeding (35.5%), infection (25.8%), and respiratory failure (20.4%).

Conclusions: This study illustrated similar survival in patients receiving a primary or staged HVAD BiVAD implant at 1 year and 2 years. This study also established that the locations of the RVAD implant (RV or RA) result in similar AE profiles.
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http://dx.doi.org/10.1016/j.healun.2020.08.006DOI Listing
December 2020

Direct postoperative protein S100B and NIRS monitoring in infants after pediatric cardiac surgery enrich early mortality assessment at the PICU.

Heart Lung 2020 Nov - Dec;49(6):731-736. Epub 2020 Sep 4.

Division of Neonatology, Pediatric Intensive Care and Neuropediatrics, Medical University of Vienna, Austria. Electronic address:

Background: Neuromonitoring using plasmatic biomarkers such as S100B and near-infrared spectroscopy (NIRS) represents a standard procedure for detecting cerebral damage after cardiac surgery. Their use in pediatric clinical assessment, however, is negligible.

Objectives: The goal of this study was to evaluate the predictive role of S100B levels and cerebral oxygenation in postoperative pediatric cardiac patients for survival and potential cerebral injuries.

Methods: A retrospective cohort study of infants after cardiac surgery. Primary outcome was survival until discharge. Intra/postoperative vital signs and laboratory data were measured and statistically analyzed.

Results: Seven out of 226 infants were non-survivors. Non-survivors had significantly lower cerebral saturation than survivors, as well as elevated S100B values at admission, associated with lower arterial pressure and higher serum lactate levels.

Conclusion: Although significant differences of S100B and crO values between survivors and non-survivors were found, no critical thresholds could be established from the data. Nevertheless, changes from the norm in these parameters should raise awareness for critical clinical development.
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http://dx.doi.org/10.1016/j.hrtlng.2020.08.014DOI Listing
March 2021

[Recommendations for Extracorporeal Membrane Oxygenation (ECMO) in COVID-19 Patients].

Wien Klin Mag 2020 Jun 10:1-6. Epub 2020 Jun 10.

Universitätsklinik für Innere Medizin I, Allgemeines Krankenhaus der Stadt Wien, Medizinische Universität Wien, Währinger Gürtel 18-20, 1090 Wien, Österreich.

The pandemic from the SARS-CoV‑2 Virus is currently challenging health care systems all over the world. Maintaining appropriate staffing and resources in healthcare facilities is essential to guarantee a safe work environment for healthcare personnel and safe patient care. Extracorporeal membrane oxygenation (ECMO) represents a valuable therapeutic option in patients with severe heart or lung failure. Although only a limited proportion of COVID-19 patients develops respiratory or circulatory failure that is refractory to conventional therapies, it is of utmost importance to clearly define criteria for the use of ECMOs in this steadily growing patient population. The ECMO working group of the Medical University of Vienna has established the following recommendations for ECMO support in COVID-19 patients.
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http://dx.doi.org/10.1007/s00740-020-00349-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7286215PMC
June 2020

Coronary artery bypass grafting and perioperative stroke: imaging of atherosclerotic plaques in the ascending aorta with ungated high-pitch CT-angiography.

Sci Rep 2020 08 17;10(1):13909. Epub 2020 Aug 17.

Division of Cardiac Surgery, Medical University of Vienna, Vienna, Austria.

Perioperative stroke is a devastating complication after coronary artery bypass graft (CABG) surgery, with atherosclerosis of the ascending aorta as important risk factor. During surgical manipulation, detachment of plaques can lead to consecutive embolization into brain-supplying arteries. High-pitch computed tomography angiography (HP-CTA) represents a non-invasive imaging modality, which provides the opportunity for comprehensive imaging of the ascending aorta, including plaque detection and advanced characterization. In our present retrospective study on 719 individuals, who had undergone HP-CTA within 6 months prior to CABG, atherosclerotic disease of the ascending aorta was evaluated with respect to perioperative stroke rates. For image analysis, the ascending aorta was divided into a proximal and distal part, consisting of four segments, and evaluated for presence and distribution of calcified and mixed plaques. All patients with perioperative stroke presented with atherosclerotic disease of the ascending aorta. The stroke rate was significantly associated with the presence and extent of atherosclerotic disease. Patients burdened with mixed plaques presented with significantly higher perioperative stroke rates. This study demonstrates that HP-CTA allows accurate evaluation of plaque extent and composition in the ascending aorta, and therefore may improve risk stratification of stroke prior to CABG.
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http://dx.doi.org/10.1038/s41598-020-70830-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7431556PMC
August 2020

A Cyanotic Newborn with a Pink Right Upper Extremity.

Case Rep Pediatr 2020 29;2020:8873156. Epub 2020 Jun 29.

Division of Pediatric Cardiology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria.

Aberrant origin of the subclavian artery (SCA) is a well-known vascular anomaly as part of congenital heart diseases with the left subclavian artery (LSCA) being more frequently affected than the right subclavian artery (RSCA). Complete isolation of the SCA is an even more infrequent aortic arch anomaly, occurring in less than 1% for the LSCA and even less for the RSCA. Isolation of the RSCA in patients with d-transposition of the great arteries (D-TGA) is even scanter with only a hand full of cases being reported in the literature. However, isolation of the RSCA has important implications on hemodynamics and surgical strategies. In this case report, we present a newborn patient with D-TGA which presented with distinct differential cyanosis. While the right upper extremity appeared pink with an oxygen saturation of 100%, the rest of the body was cyanotic. At first, this appearance was interpreted as the Harlequin phenomenon during primary care. However, detailed echocardiography revealed an aberrant origin of the RSCA from the right pulmonary artery, which led to the differential cyanosis. The patient underwent arterial switch operation on day of life two including dissection and reimplantation of the RSCA. The special hemodynamic situation of this is discussed in terms of pathophysiology and as well as its impact on perioperative and surgical management.
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http://dx.doi.org/10.1155/2020/8873156DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7341379PMC
June 2020

Diagnosis and Treatment Strategies of Outflow Graft Obstruction in the Fully Magnetically Levitated Continuous-Flow centrifugal Left Ventricular Assist Device: A Multicenter Case Series.

ASAIO J 2021 01;67(1):e52-e54

From the Department of Cardiothoracic and Vascular Surgery, German Heart Center Berlin, Berlin, Germany.

Outflow graft obstruction in left ventricular assist devices (LVADs) is a rare complication whose clinical presentation may be subtle. We present six cases of outflow graft obstruction in patients on HeartMate 3 LVAD detected between 648 and 1,222 days on support. Detection principles are described and treatment strategies discussed. Three patients were successfully managed with stents, one underwent surgical revision, one patient died despite emergency treatment, and the last patient without symptoms was listed for heart transplantation.
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http://dx.doi.org/10.1097/MAT.0000000000001213DOI Listing
January 2021

Outcomes of coronary artery bypass grafting in patients with human immunodeficiency virus infection.

J Card Surg 2020 Oct 11;35(10):2543-2549. Epub 2020 Jul 11.

Department of Surgery, Division of Cardiac Surgery, Medical University of Vienna, Vienna, Austria.

Background: With early and effective antiretroviral therapy and improved survival for persons living with human immunodeficiency virus infection (PLHIV), this patient population now faces an increasingly elevated risk of cardiovascular disease. However, the data on outcomes after coronary artery bypass grafting (CABG) for revascularization of coronary artery disease (CAD) in HIV+ patients is limited.

Methods: We conducted a retrospective analysis of 16 patients undergoing isolated CABG at the Medical University of Vienna from 2005 to 2018, who were HIV+ on admission. The primary endpoint of the study was survival. Secondary endpoints included the components of major adverse cardiac and cerebrovascular events (MACCE): cardiovascular death, stroke, myocardial infarction (MI), and repeat revascularization.

Results: Patients were followed for a median of 49 months (range, 7-142 months). Survival was 100% and 90% at 1 and 3 years after CABG, respectively. There were no strokes. MI and subsequent repeat revascularization were observed in two patients.

Conclusion: CABG provides excellent short- and midterm survival and freedom from MACCE in HIV+ patients with CAD requiring revascularization.
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http://dx.doi.org/10.1111/jocs.14828DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7586791PMC
October 2020

Recommendations for extracorporeal membrane oxygenation (ECMO) in COVID-19 patients : Consensus paper of the Medical University of Vienna.

Wien Klin Wochenschr 2020 Nov 3;132(21-22):671-676. Epub 2020 Jul 3.

University Department of Medicine I, Vienna General Hospital, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria.

The pandemic from the SARS-CoV‑2 virus is currently challenging healthcare systems all over the world. Maintaining appropriate staffing and resources in healthcare facilities is essential to guarantee a safe working environment for healthcare personnel and safe patient care. Extracorporeal membrane oxygenation (ECMO) represents a valuable therapeutic option in patients with severe heart or lung failure. Although only a limited proportion of COVID-19 patients develop respiratory or circulatory failure that is refractory to conventional treatment, it is of utmost importance to clearly define criteria for the use of ECMO in this steadily growing patient population. The ECMO working group of the Medical University of Vienna has established the following recommendations for ECMO support in COVID-19 patients.
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http://dx.doi.org/10.1007/s00508-020-01708-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7332739PMC
November 2020

Commentary: Transcending acceptable, moving toward optimal: Standardizing surgical configurations of ventricular assist device therapy.

J Thorac Cardiovasc Surg 2020 May 15. Epub 2020 May 15.

Division of Cardiology, Department of Medicine, University of Washington, Seattle, Wash. Electronic address:

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http://dx.doi.org/10.1016/j.jtcvs.2020.05.017DOI Listing
May 2020

Surgical stented transcatheter valve-in-valve implantation in atrioventricular position in children.

Multimed Man Cardiothorac Surg 2020 Jun 8;2020. Epub 2020 Jun 8.

Department of Cardiac Surgery Medical University of Vienna Spitalgasse 23, A1090 Vienna, Austria.

The Melody valve (Medtronic, Minneapolis, MN, USA) is a stented bovine jugular vein graft that was primarily approved for transcatheter implantation in a pulmonary valve position. The prosthetic valve can also be implanted in an atrioventricular position in infants and young children, and in these cases it must be modified appropriately.  In this tutorial we demonstrate the surgical preparation of a stented transcatheter Melody valve for implantation in the atrioventricular position. Additionally, we present a safe and effective method for surgical valve-in-valve implantation in a 3-year-old patient with hypoplastic left heart syndrome.
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http://dx.doi.org/10.1510/mmcts.2020.026DOI Listing
June 2020