The loss of left atrial contractile function predicts worse outcome in HFrEF: a speckle tracking study
Abstract Funding Acknowledgements Type of funding sources: None. Background in chronic heart failure (HF), high cardiac pressure induces a progressive remodeling of small pulmonary arteries up to pulmonary hypertension development. At the end of left atrial (LA) conduit function, pulmonary and left heart end-systolic pressures equalize. This might affect LA systole. Purpose we investigated whether peak atrial contraction strain (PACS), measured by speckle tracking echocardiography (STE), was independently associated with outcome in HF with reduced ejection fraction(HFrEF). Methods 168 outpatients with HFrEF and sinus-rhythm referred to our echo-labs were prospectively enrolled. After clinical and echocardiographic evaluation, off-line STE analysis was performed. The endpoints were cardiovascular (CV) death and HF hospitalization respectively. Spline knotted survival model identified the optimal cut-off value for PACS. Results The 152 included patients were stratified based on PACS < 8%(n = 76) or PACS≥8%(n = 76). Mean age was 61 ± 12, mean EF was 30 ± 9%. Characteristics of the two groups are presented in Table 1. Over a mean follow-up of 3.41 ± 1.9 years, 117 events (51 CV death, 66 HF hospitalizations) were collected. By univariate and multivariate Cox analysis, global PACS emerged as a strong and independent predictor of CV death and HF hospitalization, even after adjusting for age, sex, LV strain, E/e’, LA volume index (HR 0.6 per 5 unit decrease in PACS). Kaplan Meier curves showed a sustained divergence in event-free survival rates for the two groups (Fig.1). Conclusions The reduction of PACS significantly and independently affects CV outcome in HFrEF. Although limited to patients with sinus rhythm, it could offer additive prognostic information for HFrEF patients. Table 1 Variable PACS < 8 PACS ≥ 8 P value Age 61.5± 11.4 61.8 ± 12.7 0.4 NYHA class >2 26% (n = 39) 11% (n = 17) <0.0001 NT pro BNP 2293.7 ± 1636 1335 ± 242 0.04 E/E’ ratio 16.1 ± 9.09 12.1 ± 7.09 0.0015 LV GLS -7.28 ± 3.4 -10.17 ± 3.2 <0.001 sPAP 40.5 ± 13.7 30.3 ± 9.3 <0.0001 LAVI 64.4 ± 20.4 45.5 ± 15.8 <0.0001 PALS 9.8 ± 4.9 20.2 ± 7 <0.0001 E, peak early diastolic “E” wave; E’, medium velocity of early mitral annulus descent; GLS, global longitudinal strain; LAVI, left atrial volume index; LV, left ventricular; PACS, peak atrial contraction strain; PALS, peak atrial longitudinal strain; sPAP, systolic pulmonary artery pressure. Abstract Figure. Fig.1