Multimodality Imaging in Hypertrophic Cardiomyopathy for Risk Stratification

Abstract

In hypertrophic cardiomyopathy, multimodality imaging is crucial to confirm diagnosis, assess for presence and mechanism of left ventricular outflow tract obstruction, and risk stratification for sudden cardiac death. This review will focus on the application of imaging to assess established and emerging factors to be considered in sudden cardiac death risk stratification.

Differential diagnosis of apical hypertrophic cardiomyopathy and apical displacement of the papillary muscles: a multimodality imaging point of view

“…The major finding of ApHCM is asymmetrical hypertrophy of the LV apex. A comprehensive 2D echocardiographic examination should include LV dimensions, segmental wall thickness, right and left ventricular contractility, assessment of diastolic function, obstruction at any level in the LV, and evaluation of PM abnormalities and mitral apparatus 4,9‐11 …”

“…Apical hypertrophic cardiomyopathy is described as having an end‐diastolic apical thickness of >15 mm and an apico‐basal ratio of wall thickness of >1.3‐1.5 4,9,11,12 . However, as the apical cap is the thinnest segment of the entire LV, the threshold of wall thickness may be less in the presence of the accompanying findings 2,13 .…”

The Advantages of New Multimodality Imaging in Choosing the Optimal Management Strategy for Patients with Hypertrophic Cardiomyopathy

“…It is recommended to assess the left ventricular ejection fraction (LVEF) using biplane method of discs, and in cases when we have a difficult imaging window or when it is difficult to visualize the endocardial border, we may use cardiac magnetic resonance (CMR) [44].…”

“…Approximately 10% of patients with nonobstructive HCM progress slowly to end-stage heart failure, being candidates for heart transplantation [44]. In addition, one half of them may progress to left ventricular enlargement and remodeling, with regression of ventricular hypertrophy due to the presence of diffuse myocardial fibrosis [45,46].…”

“…There are only a few studies that have evaluated the association between left atrial volume and the risk of SCD [ 42 , 43 ]. However, there are still debates about whether left atrial enlargement is an independent predictor of SCD, or if it appears as a result of LVH, LVOT obstruction, mitral regurgitation, diastolic dysfunction or atrial arrhythmia [ 44 ]. The most frequent causes for left atrial enlargement are the mitral regurgitation, as a secondary consequence of SAM, and increased left ventricular filling pressures [ 2 ].…”