Faculty Bibliography

BACKGROUND/UNASSIGNED:Implanted cardioverter-defibrillators (ICDs) have been used in patients with hypertrophic cardiomyopathy (HCM) to prevent sudden death, and have proven lifesaving for many patients. However, experience with ICD therapy has largely been derived from relatively small HCM cohorts confined to specific countries or regions of the world. Therefore, we sought to determine the effectiveness of ICDs in preventing sudden death due to life-threatening ventricular arrhythmias in a large international multicenter HCM population. METHODS/UNASSIGNED:Databases from 25 HCM centers (8 in the United States, 9 in Europe, 4 in Asia, and 1 each in Australia, Africa, Mexico, and South America) were retrospectively interrogated to identify consecutive patients with HCM with ICDs (1992 to 2024) followed for 7±6 years (up to 32 years) for clinical outcomes. RESULTS/UNASSIGNED:A total of 3387 patients were identified (63% men). They had a mean left ventricular thickness of 22±7 mm. The participants had received ICDs at a mean age of 47±17 years. Over follow-up, 550 patients (16%) experienced ≥1 appropriate ICD therapy (2.6%/y), including 86 of the 247 implanted for secondary prevention (35% [6.4%/y]) and 464 of the 3140 implanted for primary prevention (15% [2.2%/y]). Appropriate therapy occurred in the 464 primary prevention patients at a mean age of 49±17 years, with a median time to first appropriate therapy of 4 years after ICD implantation; 16% of these received their first appropriate therapy ≥10 years after implantation, and 47% experienced multiple interventions. Independent predictors of appropriate ICD therapy included unexplained syncope, left ventricular apical aneurysms, left ventricular systolic dysfunction, and nonsustained ventricular tachycardia on ambulatory monitoring. Of the 3140 primary prevention patients, 2946 survived (94%) and 194 died (6%) (0.8%/y), including 68 due to HCM (0.3%/y), predominantly of end-stage heart failure (n=43) or stroke (n=9). In contrast, 11 patients (0.4%) died suddenly, with device failures occurring in 2.4% of those with life-threatening ventricular tachyarrhythmias. Survival free from HCM-related mortality at 10 and 20 years was 97% and 91%, respectively. CONCLUSIONS/UNASSIGNED:In this international multicenter study, the largest to date, including >3300 consecutive patients with HCM and ICDs, device therapy terminated potentially lethal ventricular tachyarrhythmias in 1 of 6 patients, with low HCM-related mortality rates for patients with ICDs. These novel data demonstrate the effectiveness of the ICD initiative, which has probably favorably altered the natural history of many patients with HCM worldwide.

BACKGROUND:Apical aneurysms in hypertrophic cardiomyopathy (HCM) have been linked to sudden cardiac death (SCD) and a nidus for thromboembolism. Uncertainty remains regarding the level of risk and significance of aneurysm size. OBJECTIVES/OBJECTIVE:The objective of the study was to determine the rate of SCD events and prevalence of apical thrombus or embolic events by size (maximum transverse dimension). METHODS:Apical aneurysms were identified in 510 patients from 10 centers, followed a median of 4.1 years for SCD events (SCD, appropriate implantable cardioverter defibrillator therapy, and resuscitated SCD) or development of apical thrombus/thromboembolism. Relationship between size and SCD events was analyzed using multivariable Cox proportional hazard models. RESULTS:In 510 HCM patients: 19% had small aneurysms (<10 mm), 39% medium (10-19 mm), 39% large (20-39 mm), and 3% very large (≥40 mm). SCD event rate was 2.1%/year, with risk increasing with increasing aneurysm size: 0.2%/year in small, 2.3%/year in medium, 3.0%/year in large and 8.2%/year in very large (P < 0.001). On multivariable analysis, greater size was associated with SCD events, independent of other risk markers or European Society of Cardiology-SCD score. Either an embolic event (3.6% of patients) or apical thrombus (10% of patients) occurred in 13% of patients and was independently associated with greater aneurysm size, 3% in small to 25% in very large aneurysms (P < 0.001). CONCLUSIONS:In a large cohort of HCM patients with apical aneurysms, rates of SCD events were high, with continuous relationship between size and risk. Small aneurysms (<10 mm) were associated with low risk for SCD events (0.2%/year), whereas aneurysms ≥10 mm with high risk (>2%/year). Although embolic events were uncommon, increasing aneurysm size was associated with the prevalence of apical thrombi.

BACKGROUND:Cardiovascular-kidney-metabolic syndrome (CKM) describes the clustering of risk factors and progression of disease at the intersection of metabolic disorders, chronic kidney disease (CKD), and cardiovascular disease (CVD). We aimed to characterize the prevalence of CKM stages and progression of CKM syndrome among diverse U.S. Hispanic/Latino adults. METHODS:The Hispanic Community Health Study/Study of Latinos (HCHS/SOL) is a population-based longitudinal cohort of 16,415 Hispanic/Latino adults aged 18-74 years from four U.S. communities. Participants completed examinations at visit 1 (V1, 2008-2011) and visit 2 (V2, 2014-2017). Data collected included body mass index, waist circumference, glucose tolerance, lipids, blood pressure, metabolic syndrome, CKD, 10-year CVD risk (to define subclinical CVD), and clinical CVD. CKM stages were defined using American Heart Association criteria: stage 0 (no CKM risk factors), stage 1 (excess/dysfunctional adiposity), stage 2 (metabolic risk factors or CKD), stage 3 (subclinical CVD or risk equivalents), and stage 4 (clinical CVD). We estimated the age-standardized prevalence of CKM stages at V1 (n=16,123) and CKM stage progression from V1 to V2 (n=11,178). All analyses were weighted and accounted for the HCHS/SOL complex survey design. RESULTS:At V1, the mean age was 41.1 years, and 52.3% were female. The distribution of CKM stages was: stage 0, 10.6% (standard error (SE): 0.4); stage 1, 26.1% (SE: 0.6); stage 2, 50.6% (SE: 0.6); stage 3, 2.4% (SE: 0.2); and stage 4, 10.3% (SE: 0.3). Over an average follow-up of six years, 10.3% (SE: 0.5) regressed to a lower CKM stage, while 21.5% (SE: 0.7) progressed to a higher CKM stage. CONCLUSIONS:Among diverse U.S. Hispanic/Latino adults, eight in ten had CKM risk factors or subclinical CVD, and one in five experienced CKM progression over six years. These findings highlight the need for targeted, early-stage interventions to prevent CKM progression and improve CKM health in Hispanic/Latino populations.

MR imaging is increasingly used in evaluation of patients with known or suspected hypertrophic cardiomyopathy (HCM), as it provides useful information on cardiac structure, function, and tissue characterization that is complementary to echocardiography. While the adverse effect of left ventricle (LV) outflow tract obstruction on blood flow patterns is well characterized by the midsystolic drop in LV ejection velocities and flow, flow patterns in HCM with mid-LV obstruction, with or without apical aneurysm, are less well characterized. MR imaging can provide additional information on alterations of blood flow patterns in these HCM phenotypes and "paradoxic" flows associated with apical aneurysms.

Atrial fibrillation (AF) is the most common sustained arrhythmia in hypertrophic cardiomyopathy (HCM) occurring in 20-25% of patients and associated with significant morbidity including stroke risk and worsening heart failure. Atrial fibrillation in HCM (HCM-AF) arises from disease-specific mechanisms distinct from non-HCM AF including HCM-related atrial structural changes (dilation/ fibrosis), biophysical abnormalities (within ion-channels), and atrial dysfunction that culminate in an HCM specific atrial-myopathy. While the adoption of contemporary AF therapies have been associated with improved clinical outcomes in non-HCM-AF populations, HCM-AF outcomes nonetheless remain worse including lower rates of rhythm control success with catheter ablation and antiarrhythmic medications. In this context, we provide support that HCM-AF is a distinct clinical entity, highlighting gaps in knowledge and care, and represents an area of need for dedicated investigation as it is unclear the effectiveness of applying therapeutics from non-HCM AF populations to HCM-AF.

UNLABELLED:Hypertrophic cardiomyopathy (HCM) is the most common monogenic cardiac disease, affecting approximately 0.2% of the general population. Despite its prevalence, it remains significantly underdiagnosed clinically. Surgical management of obstructive HCM has advanced extensively, particularly in understanding the mitral valve's contribution to left ventricular outflow tract obstruction (LVOTO). Historically, LVOTO was attributed mainly to septal hypertrophy and treated through isolated septal myectomy. However, contemporary insights highlight the importance of mitral leaflet elongation and abnormal papillary muscle dynamics in this pathology. Mitral leaflet shortening, either through horizontal plication or direct excision (ReLex), alongside the release of abnormal papillary muscle attachments, has emerged as a complementary strategy to standard septal myectomy. These combined approaches have demonstrated improved surgical outcomes, including reduced mitral regurgitation, alleviation of LVOTO, and excellent mid-term survival. This review synthesizes current evidence and clinical experiences, providing insights into mitral leaflet shortening's role and the comprehensive surgical strategies for managing obstructive HCM. SUPPLEMENTARY INFORMATION/UNASSIGNED:The online version contains supplementary material available at 10.1007/s12055-025-02051-1.

OBJECTIVE/UNASSIGNED:During septal myectomy, once the heart is arrested and drained of blood on cardiopulmonary bypass, transesophageal echocardiography can no longer assess septal thickness. In the present study, we evaluated the effectiveness of on-pump intracardiac echocardiography (OPIE) for real-time intraoperative septal thickness assessment in patients with preoperative thickness ≤2.0 cm. Our hypothesis was that OPIE measurements would be conconcordant with the pre- and postcardiopulmonary bypass transesophageal echocardiography measurements that are at present the primary operative guides. METHODS/UNASSIGNED:We retrospectively reviewed patients with hypertrophic cardiomyopathy and septal thickness ≤2.0 cm on transthoracic echocardiography who underwent septal myectomy from July 2017 to July 2024. The OPIE probe was introduced into the left-ventricular chamber during cardioplegic arrest, with repeated measurements to assess the depth and adequacy of resection. Septal thickness was evaluated pre-myectomy using transthoracic echocardiography, cardiac magnetic resonance imaging, transesophageal echocardiography, and OPIE. Lin's concordance correlation coefficients and Bland-Altman analyses were used to evaluate agreement between modalities. RESULTS/UNASSIGNED:A total of 220 patients were included with preoperative thickness ≤2.0, 56 of whom underwent myectomy with OPIE guidance. Preresection transesophageal echocardiography and OPIE demonstrated the strongest agreement of all the imaging modalities (Lin's concordance correlation coefficient, 0.81; 95% CI, 0.72-0.88), with minimal bias (-0.73) and the narrowest limits of agreement (-3.76, +2.31]. OPIE-derived resection thickness estimates were tightly clustered. In the OPIE cohort, there was 1 ventricular septal defect (1.8%) and no 30-day mortality. CONCLUSIONS/UNASSIGNED:OPIE is a reliable tool for intraoperative assessment of septal thickness, particularly in patients with mild hypertrophy.