Disease Expression and Outcomes in Black and White Adults With Hypertrophic Cardiomyopathy

Abstract

Background There is limited research on hypertrophic cardiomyopathy (HCM), which is the most common inherited cardiac disorder, in diverse populations, including Black individuals. Current literature lacks comprehensive data on HCM disease expression, comorbidities, and outcomes in this historically disadvantaged group. The purpose of this study was to examine structural HCM characteristics, comorbidities, and outcomes in a Black and White cohort with HCM. Methods and Results The study was a subgroup analysis from a longitudinal, prospective study on HCM, with supplemental chart review. The sample included adults (≥18 years) with a clinical diagnosis of HCM, who self-identified as Black/African American or White. The study sample comprised 434 individuals; 57 (13.1%) were Black, and 180 (41.5%) were women. Black patients were younger than White patients, 54.6 (13.4) versus 62.5 (14.8) years, P=0.001. Black patients were more likely to have sub-basal and diffuse hypertrophy, 22 (38.6%) versus 56 (14.9%), P<0.001, 6 (10.5%) versus 15 (4%), P=0.017, mid-LV obstruction, 7 (12.3%) versus 21 (5.5%), P=0.025, and cardiac fibrosis ≥15%, 10 (22.2%) versus 19 (8.8%), P=0.009, than White patients. Black patients were more likely to experience appropriate implantable cardioverter defibrillator interventions, 5 (38.5) versus 5 (6.8), P<0.001 and were more likely to have ≥2 sudden death risk factors. Comorbidities were largely similar between groups, though more Black participants had Class II obesity, 12 (21.8) versus 30 (8.1), P<0.001. Both groups had similar rates of genetic testing usage. Conclusions This study underscores the need for continued research of HCM in Black populations, including tailored approaches to diagnosis and precise evaluation of cardiac anatomy.

Keywords: health disparities; heart anatomy; hypertrophic cardiomyopathy; outcome; risk factor.

Figure 1. Apical akinetic aneurysm in a 65‐year‐old man with hypertrophic cardiomyopathy.

A, Apical 4‐chamber echocardiogram shows apical thickening (orange arrow) but aneurysm is not visualized due to foreshortening. Intravenous contrast is recommended for all patients with apical hypertrophic cardiomyopathy to detect aneurysm. B, Same patient after intravenous echo contrast. Red arrow, A=apical aneurysm; left ventricular cavity; white arrowheads point to mid‐left ventricular obstruction attributable to systolic complete emptying at that level. C, Same patient, 4‐chamber view cardiac magnetic resonance showing mid‐left ventricular hypertrophy, obstruction, and thin‐walled apical aneurysm. D, Delayed late gadolinium enhancement consistent with apical and mid‐left ventricular fibrosis, yellow arrows. CMR indicates cardiac magnetic resonance; and LV, left ventricular.