Correlation of exercise stress echocardiography with quality of life in mid-ventricular and apical hypertrophic cardiomyopathy

Abstract Background Exercise Stress Echocardiography (ESE) is safe, cost-effective, and non-invasive. It allows for the unmasking of specific Hypertrophic Cardiomyopathy (HCM) phenotypes if they have not yet been elucidated at rest. Moreover, ESE is used to identify the best predictors of cardiovascular events in the follow-up of this subgroup of patients. While the predictive value of many echocardiographic variables has been described, the subgroup with Mid-Ventricular and Apical HCM has been scarcely studied. Purpose There are clinical, hemodynamic, and ischemic variables obtained through Exercise Stress Echocardiography that correlate with the quality of life of patients with Mid-Ventricular and Apical Hypertrophic Cardiomyopathy. We aim to identify the variables with the strongest correlation. Methods Exercise Stress Echocardiography on a bike was performed in 25 patients with Mid-Ventricular and Apical HCM. The Kansas City Cardiomyopathy Questionnaire (KCCQ-12) was applied, and scores were correlated with exercise stress echocardiographic variables. The Shapiro-Wilk test was used to assess the distribution of continuous variables; the median and interquartile range were calculated for continuous variables, and absolute and relative frequency for categorical variables. Comparisons between the mentioned groups were performed using the Wilcoxon test, the Chi-square test, and Fisher's exact test. Results A negative correlation was observed between tricuspid regurgitation velocity and almost all KCCQ-12 subdomains (Physical limitation: p=0.0041, Symptom frequency: p=0.0025, Quality of life: p=0.0086, and social limitation: p=0.083). Additionally, a negative correlation was found between the indexed left atrial volume and the KCCQ-12 summary score (p=0.041), as well as between the mid-ventricular and/or apical peak gradient and symptom frequency (p=0.034). Furthermore, positive correlations were observed between exercise duration and physical limitation (p=0.036), and between METs achieved during ESE and the summary score (p=0.034). Patients with an implantable cardioverter-defibrillator obtained higher total scores and better symptom frequency scores (p=0.031, p=0.033). Those with better coronary flow reserve in the left anterior descending artery scored higher in quality of life (p=0.025). Patients with worse NYHA functional class and greater diastolic dysfunction had the lowest total and social limitation scores (p=0.043, p=0.033, and p=0.022). Conclusions In a cohort of 25 patients with Mid-Ventricular and Apical HCM, a statistically significant correlation was found between certain hemodynamic and ischemic variables obtained from the Exercise Stress Echocardiography and the different domains of quality of life assessed using the KCCQ-12.Main Results Part I. Main Results Part II.