Left atrial dysfunction as marker of poor outcome in patients with hypertrophic cardiomyopathy

Background. - The incremental prognostic value of left atrial (LA) dysfunction, emerging in various clinical contexts, remains poorly explored in hypertrophic cardiomyopathy (HCM). Objective. - To assess LA strain correlation with outcome in HCM. Methods. - A cohort of all 307 consecutive patients presenting with HCM between 2007 and 2017 (54 +/- 17 years; 34% women), with comprehensive echocardiography at diagnosis and LA peak longitudinal strain (PALS) and LA peak contraction strain (PACS) measurement, was enrolled and occurrence of HCM related cardiac events analysed. Results. - Clinically, atrial fibrillation (AF) was present in 13%, New York Heart Association functional class II-III in 54%, and B-type natriuretic peptide (BNP) concentration was 199 +/- 278 pg/mL. By echocardiography, left ventricular (LV) ejection fraction (EF) was 67 +/- 10%, LV thickness 21 +/- 5 mm and European Society of Cardiology HCM risk score 3 +/- 3%, with 109 patients (36%) presenting obstructive HCM (LV outflow gradient 21 +/- 32 mmHg). LA diameter was 41 +/- 8 mm [with 109 (36%) presenting LA diameter >= 40 mm], LA volume index 50 +/- 26 mL/m(2), PALS 24 +/- 13%, PACS 11 +/- 7% and LA peak systolic strain rate (LASRs) 1.7 +/- 0.6 s(-1). In addition to AF, age, BNP, LVEF and LV thickness were all independent determinants of lower PALS, with odd ratios almost unchanged after adjustment (all P <= 0.0004). At a mean follow-up of 21 (range 18-23) months, patients with adverse cardiac events (n = 65) presented with more impaired LA function (all P <= 0.0005), with a significant association between impaired PALS and worse outcome, hazard ratio 0.94 [95% confidence interval (CI) 0.92-0.97, P < 0.0001]. After comprehensive adjustment, PALS remained strongly associated with worse outcome, adjusted hazard ratio 0.86 (95% CI 0.79-0.94; P = 0.0008). Conclusions. - The present study, by gathering a unique HCM cohort, suggests a strong link between LA dysfunction and poor outcome, to be further investigated. (C) 2020 Elsevier Masson SAS. All rights reserved.