Identifying Adverse Remodeling in Hypertrophic Cardiomyopathy Phenotypes Role of Left Atrial Parameters

Abstract

Documenting adverse remodeling in absence of left ventricular outflow tract (LVOT) obstruction and mitral regurgitation in a classical hypertrophic cardiomyopathy (HCMP) phenotype is difficult. Changes in the left atrium (LA) are a consequence of progressive left ventricular (LV) fibrosis and have been shown to progress in a linear fashion. Therefore, studying LA changes for identifying adverse remodeling in HCMP patients is important. Materials and Methods:This was a prospective study which included HCMP patients and age-and gender-matched controls. Various echocardiographic parameters of adverse cardiac remodeling were investigated.Results: A total of 160 patients with HCMP and 75 age-and sex-matched controls were analyzed over a 5-year period. HCMP patients had an enlarged LA, greater segmental thickness, and mildly increased LV filling pressure. Patients with maximum LA volume >40 mL and global LA strain <21.5% showed greater maximum segmental thickness and increased ratio of pulse wave Doppler derived mitral E wave and tissue Doppler derived annular e wave with reduced LA strain and LV strain, LA emptying fraction, and strain-derived LV ejection fraction. In both groups, significant difference was not observed in age, sex, HCMP phenotype, presence or absence of LVOT obstruction, LV volume, and mitral Doppler ratio of pulse wave Doppler derived mitral E and A waves. Conclusion:Monitoring HCMP in asymptomatic patients is challenging. Assessment of adverse cardiac remodeling in classical HCMP phenotype is feasible using global LA strain and maximum LA volume. Global LA strain identifies early changes and maximum LA volume late changes of cardiac remodeling and therefore provide an early indication of disease progression in asymptomatic HCMP patients.