Sudden cardiac death in young competitive athletes due to genetic cardiac abnormalities

Journal ArticleSudden cardiac death (SCD) in young athletes is generally caused by inherited cardiac disorders. While these events are relatively few compared to other cardiac deaths, they are tragic in that death occurs in a young, otherwise healthy person. The genetic abnormalities most associated with SCD are hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, long QT syndrome, Brugada syndrome, and catecholaminergic polymorphic ventricular tachycardia. As a result of growing awareness that these deaths can be prevented, guidelines have been issued in both Europe and the United States to help screen and determine qualification for young persons who want to participate in competitive athletics. There remains debate on the how extensive screening should be, in particular over the use of the 12-lead electrocardiogram (ECG), with European guidelines mandating ECG and United States guidelines not recommending routine use of the ECG. (Anadolu Kardiyol Derg 2009; 9: Suppl 2; 17-23

Cardiac Allograft Vasculopathy in Redo-transplants: Is it More or Less the Same the Second Time Around?

Purpose: Cardiac allograft vasculopathy (CAV) continues to hinder the long-term success of heart transplant recipients.  Redo-transplantation is currently the only definitive treatment for advanced CAV. We examined whether these patients are at similar CAV-risk with the second transplantMethods: Heart recipients from 1985 to 2011 at the UTAH program were included in the study and those with CAV as an indication for redo-transplantation were identified. CAV diagnosis was made by coronary angiography and based on the 2010 ISHLT standardized nomenclature for CAV. Patient demographics, rejection history, and CAV incidence were analyzed. Results: Of the 1,169 eligible patients, 135 (11.5%) developed CAV post their first transplant; 78 cases within 10 years and 54 beyond 10 years. The mean time to CAV was 6.58 years. Of the 135 patients who developed CAV, only 21 (15.5%) ended up requiring a redo-transplant. Of the 21 retransplanted patients, 4 (19.0%) developed CAV again; 2 patients within 10 years and 2 patients beyond 10 years indicating a similar risk for CAV occurrence for first and redo-transplant. Conclusions: Our results indicate that CAV is as likely to develop in redo-transplants despite recent advances in immunosuppression and the standardized use of lipid-lowering agents. Although outcomes in redo-transplantation for the indication of CAV are favorable, efforts to better understand and minimize CAV are needed, especially in the face of scarce donor organs

Dosing and safety profile of aficamten in symptomatic obstructive hypertrophic cardiomyopathy: results from from SEQUOIA‐HCM

Background: Aficamten, a novel cardiac myosin inhibitor, reversibly reduces cardiac hypercontractility in obstructive hypertrophic cardiomyopathy. We present a prespecified analysis of the pharmacokinetics, pharmacodynamics, and safety of aficamten in SEQUOIA‐HCM (Safety, Efficacy, and Quantitative Understanding of Obstruction Impact of Aficamten in HCM). Methods and Results: A total of 282 patients with obstructive hypertrophic cardiomyopathy were randomized 1:1 to daily aficamten (5–20 mg) or placebo between February 1, 2022, and May 15, 2023. Aficamten dosing targeted the lowest effective dose for achieving site‐interpreted Valsalva left ventricular outflow tract gradient <30 mm Hg with left ventricular ejection fraction (LVEF) ≥50%. End points were evaluated during titration (day 1 to week 8), maintenance (weeks 8–24), and washout (weeks 24–28), and included major adverse cardiac events, new‐onset atrial fibrillation, implantable cardioverter‐defibrillator discharges, LVEF <50%, and treatment‐emergent adverse events. At week 8, 3.6%, 12.9%, 35%, and 48.6% of patients achieved 5‐, 10‐, 15‐, and 20‐mg doses, respectively. Baseline characteristics were similar across groups. Aficamten concentration increased by dose and remained stable during maintenance. During the treatment period, LVEF decreased by −0.9% (95% CI, −1.3 to −0.6) per 100 ng/mL aficamten exposure. Seven (4.9%) patients taking aficamten underwent per‐protocol dose reduction for site‐interpreted LVEF <50%. There were no treatment interruptions or heart failure worsening for LVEF <50%. No major adverse cardiovascular events were associated with aficamten, and treatment‐emergent adverse events were similar between treatment groups, including atrial fibrillation. Conclusions: A site‐based dosing algorithm targeting the lowest effective aficamten dose reduced left ventricular outflow tract gradient with a favorable safety profile throughout SEQUOIA‐HCM

Syndrome of reversible cardiogenic shock and left ventricular ballooning in obstructive hypertrophic cardiomyopathy

Background Cardiogenic shock from most causes has unfavorable prognosis. Hypertrophic cardiomyopathy (HCM) can uncommonly present with apical ballooning and shock in association with sudden development of severe and unrelenting left ventricular (LV) outflow obstruction. Typical HCM phenotypic features of mild septal thickening, outflow gradients, and distinctive mitral abnormalities differentiate these patients from others with Takotsubo syndrome, who have normal mitral valves and no outflow obstruction. Methods and Results We analyzed 8 patients from our 4 HCM centers with obstructive HCM and abrupt presentation of cardiogenic shock with LV ballooning, and 6 cases reported in literature. Of 14 patients, 10 (71%) were women, aged 66±9 years, presenting with acute symptoms: LV ballooning; depressed ejection fraction (25±5%); refractory systemic hypotension; marked LV outflow tract obstruction (peak gradient, 94±28 mm Hg); and elevated troponin, but absence of atherosclerotic coronary disease. Shock was managed with intravenous administration of phenylephrine (n=6), norepinephrine (n=6), β-blocker (n=7), and vasopressin (n=1). Mechanical circulatory support was required in 8, including intra-aortic balloon pump (n=4), venoarterial extracorporeal membrane oxygenation (n=3), and Impella and Tandem Heart in 1 each. In refractory shock, urgent relief of obstruction by myectomy was performed in 5, and alcohol ablation in 1. All patients survived their critical illness, with full recovery of systolic function. Conclusions When cardiogenic shock and LV ballooning occur in obstructive HCM, they are marked by distinctive anatomic and physiologic features. Relief of obstruction with targeted pharmacotherapy, mechanical circulatory support, and myectomy, when necessary for refractory shock, may lead to survival and normalization of systolic function