Clinical Characteristics and Prognostic Importance of Left Ventricular Apical Aneurysms in Hypertrophic Cardiomyopathy

Abstract

Background: Left ventricular (LV) apical aneurysms in hypertrophic cardiomyopathy (HCM) are a recognized risk marker for adverse cardiovascular events. There is variable practice among clinicians and discordance between international guidelines regarding treatment recommendations and prognostication for this important phenotype.

Objectives: The authors sought to describe the morphology, clinical course, and risk of adverse events in a large single-center cohort of HCM patients with LV apical aneurysms.

Methods: This study analyzed 160 HCM patients with an LV apical aneurysm who were evaluated in our dedicated HCM clinic between January 1997 and April 2021.

Results: Mean age was 59.1 ± 13.6 years, and 71% of these patients were male. Mean aneurysm size was 1.77 ± 1.04 cm. Over 6.2 ± 4.8 years, 14 (9%) patients had a sudden cardiac death (SCD) event, including appropriate therapy from an implantable cardioverter-defibrillator (ICD) or resuscitation from cardiac arrest (annualized event rate 1.77%/y), 39 (24%) had either a thromboembolic stroke or apical thrombus formation (2.9%/y), and 14 (9%) developed LV systolic dysfunction with an ejection fraction (EF) <50% (1.28%/y). HRs for SCD, stroke or thrombus, and EF <50% per 1-cm increase in aneurysm size were 1.69 (P = 0.007), 1.60 (P = 0.0002), and 1.63 (P = 0.01), respectively. Aneurysm size ≥2 cm was associated with a 5-year SCD rate of 9.7%, compared with 2.9% for aneurysm size <2 cm (log-rank P = 0.037). This subgroup also had higher risk of stroke/thrombus formation (HR: 2.20; P = 0.002), with an annualized event rate of 2.7%/year. A total of 39 (24%) patients reached the combined end point of SCD, stroke, or LV dysfunction (2.12%/y) with an HR of 1.47/cm increase in aneurysm size (P = 0.003) and an HR of 2.22 for patients with aneurysm size ≥2 cm (P = 0.02).

Conclusions: Increasing aneurysm size confers poorer prognosis. Aneurysm size ≥2 cm should alert potential consideration for prophylactic anticoagulation and primary prevention ICDs.

Keywords: cardiovascular magnetic resonance (CMR); echocardiography; hypertrophic cardiomyopathy (HCM); imaging; left ventricular apical aneurysm.