Cardiac allograft vasculopathy in heart transplant recipients from hepatitis C viremic donors.

BACKGROUND: Recent studies suggest the transplantation of Hepatitis C (HCV) hearts from viremic donors is associated with comparable 1 year survival to nonviremic donors. Though HCV viremia is a known risk factor for accelerated atherosclerosis, data on cardiac allograft vasculopathy (CAV) outcomes are limited. We compared the incidence of CAV in heart transplant recipients from HCV viremic donors (nucleic acid amplification test positive; NAT+) compared to non-HCV infected donors (NAT-). METHODS: We retrospectively reviewed annual coronary angiograms with intravascular ultrasound from April 2017 to August 2020 at two large cardiac transplant centers. CAV was graded according to ISHLT guidelines. Maximal intimal thickness (MIT) ≥ 0.5 mm was considered significant for subclinical disease. RESULTS: Among 270 heart transplant recipients (mean age 54; 77% male), 62 patients were transplanted from NAT+ donors. CAV ≥ grade 1 was present in 8.8% of the NAT+ versus 16.8% of the NAT- group at 1 year, 20% versus 28.8% at 2 years, and 33.3% versus 41.5% at 3 years. After adjusting for donor age, donor smoking history, recipient BMI, recipient, hypertension, and recipient diabetes, NAT+ status did not confer increased risk of CAV (HR.80; 95% CI.45-1.40, p = 0.43) or subclinical IVUS disease (HR.87; 95% CI.58-1.30, p = 0.49). Additionally, there was no difference in the presence of rapidly progressive lesions on IVUS. CONCLUSION: Our data show that NAT+ donors conferred no increased risk for early CAV or subclinical IVUS disease following transplantation in a cohort of heart transplant patients who were treated for HCV, suggesting the short-term safety of this strategy to maximize the pool of available donor hearts.

Applications of Gene Therapy in Cardiomyopathies.

Gene therapy is defined by the introduction of new genes or the genetic modification of existing genes and/or their regulatory portions via gene replacement and gene editing strategies, respectively. The genetic material is usually delivered though cardiotropic vectors such as adeno-associated virus 9 or engineered capsids. The enthusiasm for gene therapy has been hampered somewhat by adverse events observed in clinical trials, including dose-dependent immunologic reactions such as hepatotoxicity, acquired hemolytic uremic syndrome and myocarditis. Notably, gene therapy for Duchenne muscular dystrophy has recently been approved and pivotal clinical trials are testing gene therapy approaches in rare myocardial conditions such as Danon disease and Fabry disease. Furthermore, promising results have been shown in animal models of gene therapy in hypertrophic cardiomyopathy and arrhythmogenic cardiomyopathy. This review summarizes the gene therapy techniques, the toxicity risk associated with adeno-associated virus delivery, the ongoing clinical trials, and future targets.

Gene therapy vector-related myocarditis.

Gene therapy is a technique to correct genetic abnormalities, through introduction of a functional gene or through direct genome editing. Adeno-associated virus (AAV)-mediated gene replacement shows promise for targeted therapies in treatment of inherited cardiomyopathies and is the most used approach in clinical trials. However, immune responses from the host to the virus and gene product pose delivery and safety challenges. This review explores the immunological reactions to AAV-based gene therapy, their potential toxic effects, with a focus on myocarditis, and future directions for gene therapy.

International Consensus on Differential Diagnosis and Management of Patients With Danon Disease: JACC State-of-the-Art Review.

Danon disease is a rare X-linked autophagic vacuolar cardioskeletal myopathy associated with severe heart failure that can be accompanied with extracardiac neurologic, skeletal, and ophthalmologic manifestations. It is caused by loss of function variants in the LAMP2 gene and is among the most severe and penetrant of the genetic cardiomyopathies. Most patients with Danon disease will experience symptomatic heart failure. Male individuals generally present earlier than women and die of either heart failure or arrhythmia or receive a heart transplant by the third decade of life. Herein, the authors review the differential diagnosis of Danon disease, diagnostic criteria, natural history, management recommendations, and recent advances in treatment of this increasingly recognized and extremely morbid cardiomyopathy.

The Genetic Evaluation of Dilated Cardiomyopathy.

Dilated cardiomyopathy (DCM) is a common cause of heart failure and is the primary indication for heart transplantation. A genetic etiology can be found in 20-35% of patients with DCM, especially in those with a family history of cardiomyopathy or sudden cardiac death at an early age. With advancements in genome sequencing, the understanding of genotype-phenotype relationships in DCM has expanded with over 60 genes implicated in the disease. Subsequently, these findings have increased adoption of genetic testing in the management of DCM, which has allowed for improved risk stratification and identification of at risk family members. In this review, we discuss the genetic evaluation of DCM with a focus on practical genetic testing considerations, genotype-phenotype associations, and insights into upcoming personalized therapies.

Autoimmune Hepatitis-Like Syndrome Following COVID-19 Vaccination: A Systematic Review of the Literature.

OBJECTIVES: During the summer of 2021, case reports began to emerge documenting a small number of individuals who developed autoimmune hepatitis (AIH) following COVID-19 vaccination. These cases are rare and novel, and very little is known. In our systematic review, we analyzed every published case of AIH and reviewed their characteristic findings, treatment, and outcomes. METHODS: We searched PubMed, Embase, and Web of Science from December 1, 2019, to November 1, 2021. Two researchers independently extracted information from the articles about vaccine type, patient history, laboratory values, histology results, treatment regimens, and disease course. RESULTS: Thirty-two patients developed AIH-like syndromes after receiving a COVID-19 vaccine. Jaundice was the most frequently reported symptom (81%), and 19% of patients were initially asymptomatic and presented with elevated liver enzymes found during routine bloodwork. Mean alanine transaminase, aspartate transaminase, and total bilirubin were 1231 U/L, 921 U/L, and 14 mg/dL, respectively. Anti-nuclear antibody was positive in 56%, and anti-smooth muscle antibody in 28% of patients. Steroids were used in 75% of patients. Improvement or complete resolution was seen in 97% of patients. One patient died despite aggressive steroid treatment. CONCLUSION: COVID-19 vaccine-induced AIH is an uncommon association with just 32 documented cases in the literature. Clinicians should be vigilant for AIH in patients who present with liver injury following vaccination. These new findings should under not deter individuals from getting vaccinated, as the benefits of vaccination far outweigh the risks. Fortunately, COVID-19 vaccine-induced AIH appears amendable to corticosteroid therapy and appears to have a favorable outcome.

Acute myocarditis after receiving first dose of BNT162b2 mRNA vaccine.

A 40-year-old man with history of prior coronavirus disease 2019 (COVID-19) infection developed pleuritic chest pain 3 days after receiving the first dose of the BNT162b2 mRNA vaccine. Echocardiography results were significant for mild dysfunction and left ventricular hypertrophy. Cardiac magnetic resonance imaging showed myocardial edema as well as delayed enhancement in the inferior wall of the basal left ventricular myocardium, suggestive of acute myocarditis. This case describes the work-up, diagnosis, risk-stratification, and management of acute myocarditis post BNT162b2 mRNA vaccine. .

Cardiac Transplantation in Danon Disease.

BACKGROUND: Danon disease (DD) is a rare X-linked dominant cardioskeletal myopathy caused by mutations in the lysosome-associated membrane protein-2 (LAMP-2) gene that is usually lethal without cardiac transplantation. The purpose of this study was to characterize post-transplant outcomes in a large cohort of patients with DD who underwent cardiac transplantation. METHODS: The clinical phenotype and outcome data of patients with DD who underwent cardiac transplantation (n = 38; 19 males and 19 females) were obtained from 8 centers. Study outcomes included graft survival, defined as death or retransplantation, and episodes of acute cellular and antibody-mediated rejection and cardiac allograft vasculopathy at 1 year. RESULTS: Median follow-up time after transplantation for the entire cohort was 4.4 years (IQR: 1.5-12.8 years). The median age at transplant for the cohort was 20.2 years (15.8-27.9 years), with no difference in age between sexes. Median pretransplant left-ventricular ejection fraction for the entire cohort was 30% (range 11%-84%). Males had higher pretransplant aspartate aminotransferase, alanine aminotransferase and creatine phosphokinase levels than females (P < 0.001). There were 2 deaths in the entire cohort and 2 retransplants. There was no difference in actuarial graft survival between males and females (P = 0.8965); the estimated graft survival was 87.1% (95%CI: 63.6%-95.9%) at 5 years. One episode (2.7%) of antibody-mediated rejection, grade 2, and 7 episodes (19%) of acute cellular rejection, grade 2 or 3, were reported in patients who survived to discharge (6 females and 1 male; P = 0.172). CONCLUSIONS: Heart transplantation outcomes are acceptable in DD with high probabilities of 5-year graft survival for males and females suggesting that cardiac transplantation is an effective treatment option for DD patients.

Myocardial Strain and Association With Clinical Outcomes in Danon Disease: A Model for Monitoring Progression of Genetic Cardiomyopathies.

Background Myocardial strain can identify subclinical left ventricular dysfunction in various cardiac diseases, but its association with clinical outcomes in genetic cardiomyopathies remains unknown. Herein, we assessed myocardial strain in patients with Danon disease (DD), a rare X-linked autophagic disorder that causes severe cardiac manifestations. Methods and Results Echocardiographic images were reviewed and used to calculate myocardial strain from a retrospective, international registry of patients with DD. Regression analyses were performed to evaluate for an association of global longitudinal strain (GLS) and ejection fraction with the composite outcome (death, ventricular assist device, heart transplantation, and implantable cardioverter defibrillator for secondary prevention). A total of 22 patients with DD (male 14 [63.6%], median age 16.5 years) had sufficient echocardiograms for analysis. Absolute GLS was reduced with a mean of 12.2% with an apical-sparing pattern observed. Univariable regression for GLS and composite outcome showed an odds ratio of 1.32 (95% CI, 1.02-1.71) with P=0.03. For receiver operating characteristic analysis, the areas under the curve for GLS and ejection fraction were 0.810 (P=0.02) and 0.605 (P=0.44), respectively. An absolute GLS cutoff of 10.0% yielded a true positive rate of 85.7% and false positive rate of 13.3%. Conclusions In this cohort of patients with DD, GLS may be a useful assessment of myocardial function and may predict clinical outcomes. This study highlights the potential use of myocardial strain phenotyping to monitor disease progression and potentially to predict clinical outcomes in DD and other genetic cardiomyopathies.

Cardiovascular implantable electronic device therapy in patients with left ventricular assist devices: insights from TRAViATA.

BACKGROUND: There is conflicting observational data on the survival benefit cardiac implantable electronic devices (CIED) in patients with LVADs. METHODS: Patients in whom an LVAD was implanted between January 2008 and April 2017 in the multinational Trans-Atlantic Registry on VAD and Transplant (TRAViATA) registry were separated into four groups based on the presence of CIED prior to LVAD implantation: none (n = 146), implantable cardiac defibrillator (ICD) (n = 239), cardiac resynchronization without defibrillator (CRT-P) (n = 28), and CRT with defibrillator (CRT-D) (n = 111). RESULTS: A total of 524 patients (age 52 years ±12, 84.4% male) were followed for 354 (interquartile range: 166-701) days. After multivariable adjustment, there were no differences in survival across the groups. In comparison to no device, only CRT-D was associated with late right ventricular failure (RVF) (hazard ratio 2.85, 95% confidence interval [CI] 1.42-5.72, p = 0.003). There was no difference in risk of early RVF across the groups or risk of ICD shocks between those with ICD and CRT-D. CONCLUSION: In a multinational registry of patients with LVADs, there were no differences in survival with respect to CIED subtype. However, patients with a pre-existing CRT-D had a higher likelihood of late RVF suggesting significant long-term morbidity in those with devices capable of LV­lead pacing post LVAD implantation.

Cardiac transplant recipient with COVID-19 induced acute hypoxic respiratory failure: a case report.

BACKGROUND: Heart transplant recipients represent a particularly vulnerable patient population to the novel coronavirus disease 2019 (COVID-19) due to chronic immunosuppression and high rates of comorbidities. Currently, data are limited and evidence to guide management of heart transplant recipients with COVID-19 is sparse. In this case report, we provide a summary of the current literature as well as an in-depth analysis of our clinical decision-making. CASE SUMMARY: A 67-year-old female who underwent cardiac transplantation 1 year prior was found to have acute hypoxic respiratory failure due to COVID-19. Her immunosuppressant medications were modulated with discontinuation of mycophenolate and titration of tacrolimus troughs with a goal of 6-10 ng/dL. She was administered supportive treatment including convalescent plasma, remdesivir, and dexamethasone, in addition to antibiotic treatment that resulted in resolution of her symptoms within a matter of days despite her precarious disposition. DISCUSSION: This case demonstrates that it can be safe and efficacious to modulate immunosuppressant medications in cardiac transplant recipients in accordance with recommendations made by the International Society of Heart and Lung Transplantation. This case additionally demonstrates that aspects of the current literature regarding the management of COVID-19 can be safely extrapolated to cardiac transplant recipients. Providing supportive care with dexamethasone, remdesivir, and convalescent plasma as indicated can be beneficial in cardiac transplant recipients; although, the current literature regarding convalescent plasma and remdesivir is conflicting.

Outcome of patients on heart transplant list treated with a continuous-flow left ventricular assist device: Insights from the TRans-Atlantic registry on VAd and TrAnsplant (TRAViATA).

BACKGROUND: Geographic variations in management and outcomes of individuals supported by continuous-flow left ventricular assist devices (CF-LVAD) between the United States (US) and Europe (EU) is largely unknown. METHODS: We created a retrospective, multinational registry of 524 patients who received a CF-LVAD (either HVAD or Heartmate II) between January 2008 and April 2017. Follow up spanned from date of CF-LVAD implant to post-HTx period with a median follow up of 44.8 months. RESULTS: The cohort included 299 (57.1%) EU and 225 (42.9%) US patients. Although the US cohort was significantly older with a higher prevalence of comorbidities, survival was similar between the cohorts (US 63.1%, EU 68.4% at 5 years, unadjusted log-rank test p = 0.43).Multivariate analyses suggested that older age, higher body mass index, elevated creatinine, use of temporary mechanical circulatory support prior CF-LVAD, and implantation of HVAD were associated with increased mortality. Among CF-LVAD patients undergoing HTx, the median time on CF-LVAD support was shorter in the US, meanwhile US donors were younger. Finally, the pattern of adverse events (stroke, gastrointestinal bleedings, late right ventricular failure, and driveline infection) during support differed significantly between US and EU. CONCLUSIONS: Although waitlisted patients in the US on CF-LVAD have higher risk comorbid conditions, the overall outcome is similar in US and EU. Geographic variations with regards to donor characteristics, duration of CF-LVAD support prior to transplant, and adverse events on support can explain the disparity in the utilization of mechanical bridge to transplant strategy between US and EU.