Multimodality Imaging for Hypertrophic Cardiomyopathy

Abstract

Purpose of review: Hypertrophic cardiomyopathy, an inherited autosomal dominant disease, is the most common familial cardiovascular disorder and presents with heterogeneous pathobiological, clinical, and phenotypic features. This review will explore how multimodality cardiovascular imaging offers insight into understanding and identifying these heterogeneous features which are important to reliably diagnose and risk stratify patients with HCM. Recent findings: Beyond the left ventricular (LV) hypertrophy, multimodality imaging is able to fully characterize a number of structural and functional abnormalities seen in HCM such as mitral valve leaflet elongation, abnormal chordal attachment, accessory apical-basal muscle bundle, papillary muscle abnormalities, LV outflow tract (LVOT) obstruction, microvascular dysfunction, and fibrosis. These anatomical and functional abnormalities contribute to the spectrum of different HCM presentations. Recent research shows that various morphological subtypes of HCM present with distinct clinical, genetic, LVOT, and fibrosis characteristics. Late gadolinium enhancement as assessed by cardiac magnetic resonance imaging (CMR) is useful in risk stratification of patients with HCM. In addition, native T1 and extracellular volume may add to prognostication. Strain, as measured by echocardiography and CMR, and novel techniques, such as positron emission tomography, have shown promise in determining prognosis in HCM. Computed tomography evaluates not only for obstructive coronary artery disease, but also for variations in coronary anatomy. Summary: Complimentary use of these imaging modalities is crucial in comprehensive evaluation of HCM as well as in diagnosing various features of HCM, differentiating it from other cardiomyopathies, and in identifying prognosis.