Biventricular assist device implant using biatrial cannulation for restrictive cardiomyopathy.

Preoperative calculations showed that the 9-mm inlet, 6-mm outlet, 25-cc pump chambers and 65-73 bpm would be optimal for a 5-year-old patient suffering from restrictive cardiomyopathy, with a body surface area of 0.59 m2 (1.5 L/min flow for a cardiac index of 2.5). After re-sternotomy and standard bicaval cannulation for cardiopulmonary bypass, the procedure was performed under normothermic conditions and on the beating heart. Biventricular support was established with the Berlin Heart Excor using biatrial cannulation. For left atrial cannulation, induced ventricular fibrillation was used. The 9-mm inlet cannulas were inserted into the left and right atria, respectively. The 6-mm outlet cannulas were implanted using 8-mm interposition vascular grafts for the aorta and the main pulmonary artery, respectively. Cannulas were tunnelled through the epigastric space, with systems crossing outside of the body. The 25-cc chambers were used for both right ventricular assist device and left ventricular assist device support, which subsequently showed full emptying and filling.

Prognosis after heart transplant in patients with hypertrophic and restrictive cardiomyopathy. A nationwide registry analysis.

INTRODUCTION AND OBJECTIVES: Posttransplant outcomes among recipients with a diagnosis of hypertrophic cardiomyopathy (HCM) or restrictive cardiomyopathy (RCM) remain controversial. METHODS: Retrospective analysis of a nationwide registry of first-time recipients undergoing isolated heart transplant between 1984 and 2021. One-year and 5-year mortality in recipients with HCM and RCM were compared with those with dilated cardiomyopathy (DCM). RESULTS: We included 3703 patients (3112 DCM; 331 HCM; 260 RCM) with a median follow-up of 5.0 [3.1-5.0] years. Compared with DCM, the adjusted 1-year mortality risk was: HCM: HR, 1.38; 95%CI, 1.07-1.78; P=.01, RCM: HR, 1.48; 95%CI, 1.14-1.93; P=.003. The adjusted 5-year mortality risk was: HCM: HR, 1.17; 95%CI, 0.93-1.47; P=.18; RCM: HR, 1.52; 95%CI, 1.22-1.89; P<.001. Over the last 20 years, the RCM group showed significant improvement in 1-year survival (adjusted R2=0.95) and 5-year survival (R2=0.88); the HCM group showed enhanced the 5-year survival (R2=0.59), but the 1-year survival remained stable (R2=0.16). CONCLUSIONS: Both RCM and HCM were linked to a less favorable early posttransplant prognosis compared with DCM. However, at the 5-year mark, this unfavorable difference was evident only for RCM. Notably, a substantial temporal enhancement in both early and late mortality was observed for RCM, while for HCM, this improvement was mainly evident in late mortality.

Impact of the new heart allocation policy on patients with restrictive, hypertrophic, or congenital cardiomyopathies.

BACKGROUND: Patients with restrictive or hypertrophic cardiomyopathy (RCM/HCM) and congenital heart disease (CHD) do not derive clinical benefit from inotropes and mechanical circulatory support. Concerns were expressed that the new heart allocation system implemented in October 2018 would disadvantage these patients. This paper aimed to examine the impact of the new adult heart allocation system on transplantation and outcomes among patients with RCM/HCM/CHD. METHODS: We identified adult patients with RCM/HCM/CHD in the United Network for Organ Sharing (UNOS) database who were listed for or received a cardiac transplant from April 2017-June 2020. The cohort was separated into those listed before and after allocation system changes. Demographics and recipient characteristics, donor characteristics, waitlist survival, and post-transplantation outcomes were analyzed. RESULTS: The number of patients listed for RCM/HCM/CHD increased after the allocation system change from 429 to 517. Prior to the change, the majority RCM/HCM/CHD patients were Status 1A at time of transplantation; afterwards, most were Status 2. Wait times decreased significantly for all: RCM (41 days vs 27 days; P<0.05), HCM (55 days vs 38 days; P<0.05), CHD (81 days vs 49 days; P<0.05). Distance traveled increased for all: RCM (76 mi. vs 261 mi, P<0.001), HCM (88 mi. vs 231 mi. P<0.001), CHD (114 mi vs 199 mi, P<0.05). Rates of transplantation were higher for RCM and CHD (P<0.01), whereas post-transplant survival remained unchanged. CONCLUSIONS: The new allocation system has had a positive impact on time to transplantation of patients with RCM, HCM, and CHD without negatively influencing survival.

Left Ventricular Assist Device Implantation in Hypertrophic and Restrictive Cardiomyopathy: A Systematic Review.

Left ventricular assist device (LVAD) implantation in patients with advanced heart failure due to hypertrophic or restrictive cardiomyopathy (HCM/RCM) presents technical and physiologic challenges. We conducted a systematic review of observational studies to evaluate the utilization and clinical outcomes associated with LVAD implantation in patients with HCM/RCM and compared these to patients with dilated or ischemic cardiomyopathy (DCM/ICM). We searched MEDLINE, EMBASE, and Scopus from inception through May 2019 and included appropriate studies describing the use of an LVAD in patients with HCM/RCM. We identified six studies with a total of 2,766 patients with HCM/RCM and advanced heart failure, among whom 338 patients (12.2%) underwent LVAD implantation. In patients listed for transplant, the rate of LVAD implantation was significantly lower in patients with HCM/RCM compared to that in patients with DCM/ICM (4.4% vs. 18.2%, p < 0.001). Adverse clinical outcomes were significantly higher in HCM/RCM than in DCM/ICM, including operative/short-term mortality (14.0% vs. 9.0%), right ventricular failure (50.0% vs. 21.0%), infection (15.5% vs. 11.2%), bleeding (40.2% vs. 12.5%), renal failure (15.0% vs. 5.1%), stroke (5.0% vs. 2.4%), and arrhythmias (18.0% vs. 7.7%) (all p values <0.001).

Pediatric patient with restrictive cardiomyopathy on staged biventricular assist device support with Berlin Heart EXCOR® underwent heart transplantation successfully: the first case in Japan.

Pure restrictive cardiomyopathy is a strong risk factor for poor outcomes in children with cardiomyopathy on ventricular assist devices. Owing to concomitant right heart failure, children with end-staged restrictive cardiomyopathy who are supported with a ventricular assist device often require a biventricular assist device, which is another risk factor for waitlist mortality in heart transplantation candidates. Herein, we report the case of a 3-year-old boy with pure restrictive cardiomyopathy who successfully underwent heart transplantation after 12 months of support with staged biventricular assist devices. Owing to the progression of diastolic dysfunction, the left ventricular assist device could not provide adequate circulation support. Despite the provision of biventricular assist device support, the patient required a complex management strategy that involved balancing the left and right ventricular assist device supports. We were able to stabilize the patient by careful synchronization of the supports and proceeded to heart transplantation. TRIAL REGISTRATION: Clinical Registration No.: Institutional Review Board of Osaka University Hospital, approval no. 16105.

Comparing outcomes for infiltrative and restrictive cardiomyopathies under the new heart transplant allocation system.

The new heart transplantation (HT) allocation policy was introduced on 10/18/2018. Using the UNOS registry, we examined early outcomes following HT for restrictive cardiomyopathy, hypertrophic cardiomyopathy, cardiac sarcoidosis, or cardiac amyloidosis compared to the old system. Those listed who had an event (transplant, death, or waitlist removal) prior to 10/17/2018 were in Era 1, and those listed on or after 10/18/2018 were in Era 2. The primary endpoint was death on the waitlist or delisting due to clinical deterioration. A total of 1232 HT candidates were included, 855 (69.4%) in Era 1 and 377 (30.6%) in Era 2. In Era 2, there was a significant increase in the use of temporary mechanical circulatory support and a reduction in the primary endpoint, (20.9 events per 100 PY (Era 1) vs. 18.6 events per 100 PY (Era 2), OR 1.98, p = .005). Median waitlist time decreased (91 vs. 58 days, p < .001), and transplantation rate increased (119.0 to 204.7 transplants/100 PY for Era 1 vs Era 2). Under the new policy, there has been a decrease in waitlist time and waitlist mortality/delisting due to clinical deterioration, and an increase in transplantation rates for patients with infiltrative, hypertrophic, and restrictive cardiomyopathies without any effect on post-transplant 6-month survival.

Early degeneration of two different tricuspid bioprostheses in restrictive cardiomyopathy.

Early degeneration of tricuspid bioprostheses is a rare, but extremely serious, complication. Several mechanisms have been described, both for surgically implanted and transcatheter bioprosthesis. We report a case of early degeneration of tricuspid porcine bioprosthesis and a subsequent transcatheter valve-in-valve bovine prosthesis due to severe fibrosis with leaflet retraction in a patient with restrictive cardiomyopathy who finally underwent orthotopic heart transplantation.

Endovascular treatment of stroke in children under 2 years with heart failure and ventricular assist device.

INTRODUCTION: Strokes in children are characterised by a high mortality rate while, at the same time, the low number of cases makes it difficult to gain practical experience. As heart disease is the most common risk factor, and as more and more cardiological interventions are being carried out, an increase in the incidence of paediatric stroke is expected. In some cases a transplant is required. While waiting for a donor, the use of ventricular assist devices may be necessary. These present with a high rate of neurological complications. We present two cases of children under 2 years of age awaiting heart transplantation supported by ventricular assist devices who had a stroke which was treated by endovascular techniques. Case 1: A 16-month-old boy with restrictive cardiomyopathy who was listed for a cardiac transplant. At 20 months he required an implantation of an external biventricular support device (Berlin Heart) and had a left hemisphere stroke at 23 months. An intra-arterial approach was used and produced good clinical results. One month later, a heart transplant was performed successfully. Case 2: An 18-month-old girl with non-compacted dilated cardiomyopathy included in the cardiac transplant programme and in need of a Levitronix Centrimag ventricular assist device presented with an acute left hemisphere stroke at 23 months. An intra-arterial procedure was carried out leading to positive clinical results except for residual right hypertonia. Seven months later she received her transplant. CONCLUSION: As a result of the difficulty in performing arterial puncture, the small vessel calibre and the limitation in the use of iodated contrast, there are certain limitations to endovascular treatment of strokes in children that can lead to complications. A multidisciplinary approach to managing such cases would be helpful.

Contemporary Outcomes of Pediatric Restrictive Cardiomyopathy: A Single-Center Experience.

BACKGROUND: Pediatric restrictive cardiomyopathy (RCM) has high mortality in historical cohorts, and traditional management often involves early referral for heart transplantation (HTx). This study sought to determine outcomes of pediatric RCM at a center that has favored medical management over early listing for HTx. METHODS: All patients (N = 43) with pure RCM phenotype (RCM, N = 26) and hypertrophic cardiomyopathy with restrictive physiology (RCM/HCM, N = 17) managed at our center over a 15-year period were investigated. Outcomes of those listed for HTx (N = 18) were compared to a benchmark of contemporaneous pediatric RCM patients in the UNOS database (N = 377). Proportional hazards models were used to determine predictors of adverse outcomes. RESULTS: The mean age was 11 ± 9 years and 49% were male. 14 of 18 patients listed received HTx. Overall mortality (12%) was identical between the phenotypes; however, RCM patients were more likely to be listed (P = 0.001) and receive HTx (P = 0.02) compared to RCM/HCM. Prior to HTx, 60% had documented arrhythmia, 16% had cardiac arrest, and 7% required mechanical circulatory support. 4 of 17 patients with an ICD/PM received device therapies (four of five shocks appropriate for VT/VF, and two effective anti-tachycardia pacing interventions). Outcomes of those listed for HTx at our center were similar to the UNOS benchmark. In multivariate analysis, markers of congestive heart failure were associated with adverse outcomes. CONCLUSION: Heart failure and arrhythmia treatments can delay or possibly prevent the need for HTx in some cases of pediatric RCM. Survival post-HTx is not compromised using this approach.

Mechanical Circulatory Support Device Utilization and Heart Transplant Waitlist Outcomes in Patients With Restrictive and Hypertrophic Cardiomyopathy.

BACKGROUND: Patients with restrictive cardiomyopathy (RCM) and hypertrophic cardiomyopathy (HCM) generally are considered poor candidates for mechanical circulatory support devices (MCSDs) and often not able to be bridged mechanically to heart transplantation. This study characterized MCSD utilization and transplant waitlist outcomes in patients with RCM/HCM under the current allocation system and discusses changes in the era of the new donor allocation system. METHODS AND RESULTS: Patients waitlisted from 2006 to 2016 in the United Network for Organ Sharing registry were stratified by RCM/HCM versus other diagnoses. MCSD utilization and waitlist duration were analyzed by propensity score models. Waitlist outcomes were assessed by cumulative incidence functions with competing events. Predictors of waitlist mortality or delisting for worsening status in patients with RCM/HCM were identified by proportional hazards model. Of 30 608 patients on the waitlist, 5.1% had RCM/HCM. Patients with RCM/HCM had 31 fewer waitlist days (P<0.01) and were ≈26% less likely to receive MCSD (P<0.01). Cumulative incidence of waitlist mortality was similar between cohorts; however, patients with RCM/HCM had higher incidence of heart transplantation. Predictors of waitlist mortality or delisting for worsening status in patients with RCM/HCM without MCSD support included estimated glomerular filtration rate <60 mL/min per 1.73 m2, pulmonary capillary wedge pressure >20 mm Hg, inotrope use, and subjective frailty. CONCLUSIONS: Patients with RCM/HCM are less likely to receive MCSD but have similar waitlist mortality and slightly higher incidence of transplantation compared with other patients. The United Network for Organ Sharing RCM/HCM risk model can help identify patients who are at high risk for clinical deterioration and in need of expedited heart transplantation.

Assessment of cerebral microbleeds by susceptibility-weighted imaging at 3T in patients with end-stage organ failure.

PURPOSE: Cerebral microbleeds (CMBs) are small rounded lesions representing cerebral hemosiderin deposits surrounded by macrophages that results from previous microhemorrhages. The aim of this study was to review the distribution of cerebral microbleeds in patients with end-stage organ failure and their association with specific end-stage organ failure risk factors. MATERIALS AND METHODS: Between August 2015 and June 2017, we evaluated 15 patients, 9 males, and 6 females, (mean age 65.5 years). Patients population was subdivided into three groups according to the organ failure: (a) chronic kidney failure (n = 8), (b) restrictive cardiomyopathy undergoing heart transplantation (n = 1), and (c) end-stage liver failure undergoing liver transplantation (n = 6). The MR exams were performed on a 3T MR unit and the SWI sequence was used for the detection of CMBs. CMBs were subdivided in supratentorial lobar distributed, supratentorial non-lobar distributed, and infratentorial distributed. RESULTS: A total of 91 microbleeds were observed in 15 patients. Fifty-nine CMBs lesions (64.8%) had supratentorial lobar distribution, 17 CMBs lesions (18.8%) had supratentorial non-lobar distribution and the remaining 15 CMBs lesions (16.4%) were infratentorial distributed. An overall predominance of supratentorial multiple lobar localizations was found in all types of end-stage organ failure. The presence of CMBs was significantly correlated with age, hypertension, and specific end-stage organ failure risk factors (p < 0.001). CONCLUSIONS: CMBs are mostly founded in supratentorial lobar localization in end-stage organ failure. The improved detection of CMBs with SWI sequences may contribute to a more accurate identification of patients with cerebral risk factors to prevent complications during or after the organ transplantation.

Dysregulated autophagy in restrictive cardiomyopathy due to Pro209Leu mutation in BAG3.

Myofibrillary myopathies (MFM) are hereditary myopathies histologically characterized by degeneration of myofibrils and aggregation of proteins in striated muscle. Cardiomyopathy is common in MFM but the pathophysiological mechanisms are not well understood. The BAG3-Pro209Leu mutation is associated with early onset MFM and severe restrictive cardiomyopathy (RCM), often necessitating heart transplantation during childhood. We report on a young male patient with a BAG3-Pro209Leu mutation who underwent heart transplantation at eight years of age. Detailed morphological analyses of the explanted heart tissue showed intracytoplasmic inclusions, aggregation of BAG3 and desmin, disintegration of myofibers and Z-disk alterations. The presence of undegraded autophagosomes, seen by electron microscopy, as well as increased levels of p62, LC3-I and WIPI1, detected by immunohistochemistry and western blot analyses, indicated a dysregulation of autophagy. Parkin and PINK1, proteins involved in mitophagy, were slightly increased whereas mitochondrial OXPHOS activities were not altered. These findings indicate that altered autophagy plays a role in the pathogenesis and rapid progression of RCM in MFM caused by the BAG3-Pro209Leu mutation, which could have implications for future therapeutic strategies.

Restrictive Cardiomyopathy or Constrictive Pericarditis: An Unresolved Conundrum.

Cardiomyopathy may have a variety of causes and may lead to significant morbidity. Often, there is no "perfect" treatment. New investigative techniques may add insight but retain the possibility of uncertainty. The distinction between restrictive cardiomyopathy and pericardial constriction may be challenging, particularly when considering the incidence of these entities. This distinction may significantly impact patient management and this is becoming increasingly important in the context of donor organ austerity. We present a case of a 17-year-old male to illustrate the overlap highlighting this debate and our subsequent management.

Hip and knee arthroplasty are common among patients with transthyretin cardiac amyloidosis, occurring years before cardiac amyloid diagnosis: can we identify affected patients earlier?

Transthyretin cardiac amyloidosis (ATTR-CA) causes a restrictive cardiomyopathy in older adults, often diagnosed at advanced stages when emerging therapies in late phase clinical trials may not have clinical benefit. This investigation aimed to detect clinical entities that may provide more advanced warning of ATTR-CA. Since ATTR preferentially deposits in ligaments, tendons, and articular cartilage, we hypothesized that ATTR-CA patients have a greater prevalence of total hip (THA) and knee (TKA) arthroplasties compared with the general population, and that arthroplasty occurs significantly before ATTR-CA diagnosis. Three-hundred and thirteen patients with cardiac amyloidosis (172 with ATTR-CA, 141 with light-chain) from our institutional database were analyzed and compared to published data in over 300 million patients. Overall, 23.3% of patients with ATTR-CA and 9.2% of patients with light-chain cardiac amyloidosis (AL-CA) underwent lower extremity arthroplasty. Compared to the general population, both THA and TKA were significantly more common among patients with ATTR-CA (THA: RR 5.61, 95% CI 2.25-4.64; TKA: RR 3.32, 95% CI 2.25-4.64) but not those with AL-CA (THA: RR 1.87, 95% CI 0.85-4.08; TKA: RR 1.42, 95% CI 0.73-2.84). On an average, arthroplasty occurred 7.2 years before ATTR-CA diagnosis.

Heart and heart-liver transplantation in patients with hemochromatosis.

BACKGROUND: Hemochromatosis predisposes to dilated or restrictive cardiomyopathy which can progress to end-stage heart failure, requiring the use of advanced heart therapies including heart (HT) and heart liver (HLT) transplantation. Little is known about the characteristics and outcomes of these patients. METHODS AND RESULTS: We queried the United Network for Organ Sharing (UNOS) registry for all patients listed for HT or HLT for a diagnosis of 'hemochromatosis' between 1987 and 2014. Waitlist and post-transplantation outcomes were compared between patients with hemochromatosis (HT vs HLT) and other etiologies. Of the 81,356 adults listed for heart transplantation, 23 patients with hemochromatosis were identified (16 listed for HLT; and 7 listed for HT). Compared with other etiologies, HC patients were younger (39 vs 51years, p<0.0001), and more likely to need inotropes (56.5% vs 25.6%, p=0.003) and mechanical ventilation (13% vs 3.4%, p=0.041). Cumulative hazards of waitlist mortality or delisting were higher in hemochromatosis patients than for other etiologies of heart failure (p<0.001). There were 4 HT and 4 HLT during the study period. Post-transplantation, patients with HC had a 1- and 2-year cumulative survival of 88% and 75%, respectively. CONCLUSIONS: Both HT and HLT are viable options for patients with hemochromatosis. Patients with hemochromatosis are younger with increased wait-list mortality compared with other etiologies.