Left atrial myopathy is associated with exercise capacity and ventilatory efficiency in hypertrophic cardiomyopathy

Abstract Funding Acknowledgements Type of funding sources: None. Background Data about the predictive value of left atrial (LA) myopathy for exercise capacity and ventilatory efficiency in patients with hypertrophic cardiomyopathy (HCM) are limited. Purpose The aim of this study was to evaluate the association of LA myopathy, evaluated by echocardiography LA strain, with exercise capacity and ventilatory efficiency, evaluated by cardiopulmonary exercise testing (CPET), in HCM patients. Methods In total, 241 consecutive HCM patients (51 ± 16 years old; 67.2% male) on sinus rhythm that underwent CPET and transthoracic echocardiography at the same visit were studied. Exercise capacity (maximal oxygen consumption/predicted [%peakVO2]) and ventilatory efficiency (ventilation/carbon dioxide output [VE/VCO2] slope) were assessed by CPET. LA myopathy was examined by speckle tracking myocardial deformation parameters: LA reservoir, conduit and booster strain. Results All the three LA strain values were univariate predictors of exercise capacity and ventilatory efficiency. Among them, LA reservoir strain had the higher r correlation coefficient for predicting both %peakVO2 and VE/VCO2 slope and was included in multivariable analyses. LA reservoir strain, male gender and E/E’ ratio were independent predictors of exercise capacity. LA reservoir strain, male gender, non-sustained ventricular tachycardia and LA volume index were independent predictors of ventilatory efficiency (Table). Conclusion LA myopathy, as reflected by the LA strain values, was associated with exercise capacity and ventilatory efficiency in HCM individuals. LA reservoir strain was the only common independent predictor for %peakVO2 and VE/VCO2 slope. Abstract Table