Accurate predictors of appropriate
implantable cardioverter defibrillator (ICD)
therapy in
hypertrophic cardiomyopathy (HCM) patients are lacking. Both left atrial volume index (LAVI) and global longitudinal strain (GLS) have been proposed as prognostic markers in HCM patients. The specific value of LAVI and GLS to predict appropriate ICD
therapy in high-risk HCM patients was studied. LAVI and 2-dimensional speckle tracking-derived GLS were assessed in 92 HCM patients undergoing ICD implantation (69 % men, mean age 50 ± 14 years). During long-term follow-up, appropriate ICD
therapies, defined as antitachycardia pacing and/or
shock for ventricular
arrhythmia, were recorded. Appropriate ICD
therapy occurred in 21 patients (23 %) during a median follow-up of 4.7 (2.2-8.2) years. Multivariate analysis revealed LAVI (p = 0.03) and GLS (p = 0.04) to be independent predictors of appropriate ICD
therapy. Both LAVI and GLS showed higher accuracy to predict appropriate ICD
therapy compared to presence of ≥1 conventional
sudden cardiac death (SCD) risk factor(s) [area under the curve 0.76 (95 % CI 0.65-0.87) and 0.65 (95 % CI 0.54-0.77) versus 0.52 (95 % CI 0.43-0.58) respectively, p < 0.001]. No patient with both LAVI <34 mL/m(2) and GLS <-14 % experienced appropriate ICD
therapy. Assessment of both LAVI and GLS on top of conventional SCD risk factors provided incremental clinical predictive value for appropriate ICD
therapy, as shown by likelihood ratio test (p < 0.001) and integrated discrimination improvement index (0.17, p < 0.001). LAVI and GLS provide high negative predictive value for appropriate ICD
therapy in high-risk HCM patients. Additionally to conventional SCD risk factors, both parameters may be useful to optimize criteria and timing for ICD implantation in these patients.