Faculty Bibliography

Hypertrophic cardiomyopathy is a common but underrecognized cardiac disorder characterized by a heterogenous phenotype that includes increased left ventricular thickness, outflow obstruction, diastolic dysfunction, and arrhythmia. Hypertrophic cardiomyopathy is often heritable and associated with pathogenic variants in sarcomeric genes. While not curable, an integrated approach involving medical, interventional, and surgical care can have a considerable impact on disease burden, quality of life, and mortality. This review provides a practical overview of important topics in hypertrophic cardiomyopathy, including evaluation of differential diagnosis, imaging, provocation of left ventricular outflow obstruction, treatment of obstructive and nonobstructive hypertrophic cardiomyopathy with negative inotropic therapy and myosin inhibition, as well as surgical and interventional approaches to septal reduction and mitral valve intervention.

Ventricular arrhythmias (VA) are a major cause of morbidity and mortality in patients with coronary artery disease (CAD). Current guidelines recommend revascularization of significant CAD to improve survival in patients with ventricular fibrillation (VF), polymorphic ventricular tachycardia (VT), or those who are post-cardiac arrest. However, revascularization is not recommended for CAD patients with suspected scar-mediated monomorphic VT. There is a paucity of data detailing the utility of revascularization in reducing VA in CAD patients who do not present with acute coronary syndrome (ACS) and are not immediately post-cardiac arrest, which is the focus of this review. Medline, Scopus, and the Cochrane Central Register of Controlled Trials were systematically searched to identify relevant studies addressing this question. Studies that included patients presenting with ACS or those who were immediately post-cardiac arrest at the time of revascularization were excluded. In total, five studies comprising 2663 patients were reviewed.

BACKGROUND:In patients with diabetes and multivessel coronary artery disease, percutaneous coronary intervention (PCI) has been associated with higher long-term cardiovascular mortality compared to coronary artery bypass grafting (CABG), but the specific causes of death are not well known. We aimed to determine the causes of death among patients with diabetes and multivessel disease undergoing coronary revascularization with PCI versus CABG. METHODS:We analyzed the centrally adjudicated causes of death of 1,900 participants in the FREEDOM trial. Cause-specific hazard ratios (csHR) were used to compare mortality rates. RESULTS:There were 197 deaths during the five years of follow-up, 63.5% were classified as cardiovascular deaths and the remaining (36.5%), non-cardiovascular deaths. Sudden cardiac death was the most common cause of cardiovascular mortality (40% of all cardiovascular deaths), followed by myocardial infarction deaths (16% of all cardiovascular deaths). Compared to CABG, PCI was associated with increased ischemic-related mortality, namely sudden cardiac death (csHR: 2.04;95%CI: 1.13 to 3.70; p=0.02) and the composite of sudden cardiac death and myocardial infarction death (csHR: 2.10, 95%CI: 1.27 to 3.48, p=0.004). PCI was associated with a non-significant increase in overall cardiovascular mortality compared to CABG (csHR: 1.35;95%CI: 0.95 to 1.93; p=0.09). CONCLUSIONS:Sudden cardiac death was the most common cause of long-term mortality among patients with diabetes and multivessel coronary artery disease undergoing a revascularization procedure. Compared to CABG, PCI was associated with increased long-term rates of ischemic-related mortality. Operative techniques and secondary prevention should target reducing post-revascularization spontaneous myocardial infarction in patients treated with PCI.

The field of interventional cardiology (IC) has evolved dramatically over the past 40 years. Training and certification in IC have kept pace, with the development of accredited IC fellowship training programs, training statements, and subspecialty board certification. The application process, however, remained fragmented with lack of a universal process or time frame. In recent years, growing competition among training programs for the strongest candidates resulted in time-limited offers and high-pressure situations that disadvantaged candidates. A grassroots effort was recently undertaken by a Society for Cardiovascular Angiography & Interventions task force, to create equity in the system by establishing a national Match for IC fellowship. This manuscript explores the rationale, process, and implications of this endeavor.

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/CONCLUSIONS: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.

The long-term safety of heart transplants from hepatitis C viremic (NAT+) donors remains uncertain. We conducted a prospective study of all patients who underwent heart transplantation at our center from January 2018 through August 2020. Routine testing was performed to assess for donor-derived cell-free DNA, acute cellular rejection (ACR), antibody-mediated rejection (AMR), and cardiac allograft vasculopathy (CAV). Allograft dysfunction and mortality were also monitored. Seventy-five NAT- recipients and 32 NAT+ recipients were enrolled in the study. All NAT+ recipients developed viremia detected by PCR, were treated with glecaprevir/pibrentasvir at the time of viremia detection, and cleared the virus by 59 days post-transplant. Patients who underwent NAT testing starting on post-operative day 7 (NAT+ Group 1) had significantly higher viral loads and were viremic for a longer period compared with patients tested on post-operative day 1 (NAT+ Group 2). Through 3.5 years of follow-up, there were no statistically significant differences in timing, severity, or frequency of ACR in NAT+ recipients compared with the NAT- cohort, nor were there differences in noninvasive measures of graft injury, incidence or severity of CAV, graft dysfunction, or mortality. There were five episodes of AMR, all in the NAT- group. There were no statistically significant differences between Group 1 and Group 2 NAT+ cohorts. Overall, these findings underscore the safety of heart transplantation from NAT+ donors.