The Prognostic Implications of Two-Dimensional Speckle Tracking Echocardiography in Hypertrophic Cardiomyopathy: Current and Future Perspectives
Two-dimensional speckle tracking echocardiography represents a novel, simple, and reproducible technique for the estimation of left ventricular myocardial deformation (strain) and the evaluation of left ventricular twist mechanics. During the last few years, its clinical and prognostic implications in cardiomyopathies and hypertrophic cardiomyopathy (HCM), in particular, have been rapidly increasing. Reduced global longitudinal strain is associated with more severe disease and confers an increased risk for major cardiac events, independently of other clinical and echocardiographic risk factors. Left ventricular dyssynchrony also seems promising as a risk factor for sudden cardiac events. With respect to left atrial mechanics, left atrial reservoir, conduit, and contractile strain may also confer an increased prognostic value for atrial fibrillation, major cardiac events, and even sudden death. Although right ventricular global longitudinal strain is impaired in HCM compared with healthy controls and individuals with physiological hypertrophy, its prognostic significance is currently unknown. Conclusively, 2-dimensional speckle tracking imaging seems promising for HCM. However, future studies are needed to incorporate this new imaging technique in the standard evaluation of an HCM individual.