Ratio of transmitral early filling velocity to early diastolic strain rate predicts long-term risk of cardiovascular morbidity and mortality in the general population.

Abstract

It has previously been demonstrated that the ratio of early mitral inflow velocity to global diastolic strain rate (E/e'sr) is a significant predictor of cardiac events in specific patient populations. The utility of this measurement to predict cardiovascular events in a general population has not been evaluated. A total of 1238 participants in a general population study underwent a health examination including echocardiography where global longitudinal strain (GLS) and E/e'sr were determined. The primary endpoint was the composite of incident heart failure (HF), acute myocardial infarction (AMI) or cardiovascular death (CVD). During follow-up (median 11 years), 140 (11.3%) participants reached the composite endpoint. E/e'sr was associated with adverse outcome [HR 1.17 95% CI (1.13-1.21); P < 0.001, per 10 cm increase]. After multivariable adjustment for echocardiographic and clinical parameters, E/e'sr remained an independent predictor of the composite endpoint [HR 1.08, 95% CI (1.02-1.13); P = 0.003] as opposed to E/e' [HR 1.03, 95% CI (0.99-1.06); P = 0.11 per 1 unit increase]. Global longitudinal strain modified the relationship between E/e'sr and outcome (P for interaction = 0.015). E/e'sr was a stronger predictor in participants with good systolic function as determined by GLS (GLS > 18%) after multivariable adjustment, when compared to participants with reduced systolic function (GLS < 18%) [HR 1.28 95% CI (1.06-1.54); P = 0.011, and HR 1.08 95% CI (1.02-1.14); P = 0.012, respectively). E/e'sr provided incremental information [Harrell's C-index: 0.839 (0.81-0.87) vs. 0.844 (0.82-0.87); P = 0.045] beyond the SCORE risk chart. In the general population, E/e'sr provides independent and incremental prognostic information regarding cardiovascular morbidity and mortality. Additionally, E/e'sr is a stronger predictor of cardiac events than E/e'.