Layer-specific systolic and diastolic strain in hypertensive patients with and without mild diastolic dysfunction

Abstract

This study sought to examine layer-specific longitudinal and circumferential systolic and diastolic strain, strain rate (SR) and diastolic time intervals in hypertensive patients with and without diastolic dysfunction. Fifty-eight treated hypertensive patients were assigned to normal diastolic function (NDF, N=39) or mild diastolic dysfunction (DD, N=19) group. Layer-specific systolic and diastolic longitudinal and circumferential strains and SR were assessed. Results showed no between-group difference in left ventricular mass index (DD: 92.1±18.1 vs NDF: 88.4±16.3; P=0.44). Patients with DD had a proportional reduction in longitudinal strain across the myocardium (endocardial for DD −13±4%; vs NDF −17±3, P<0.01; epicardial for DD −10±3% vs NDF −13±3%, P<0.01; global for DD: −12±3% vs NDF: −15±3, P=0.01), and longitudinal mechanical diastolic impairments as evidenced by reduced longitudinal strain rate of early diastole (DD 0.7±0.2L/s vs NDF 1.0±0.3L/s, P<0.01) and absence of a transmural gradient in the duration of diastolic strain (DD endocardial: 547±105ms vs epicardial: 542±113ms, P=0.24; NDF endocardial: 566±86ms vs epicardial: 553±77ms, P=0.03). Patients with DD also demonstrate a longer duration of early circumferential diastolic strain (231±71ms vs 189±58ms, P=0.02). In conclusion, hypertensive patients with mild DD demonstrate a proportional reduction in longitudinal strain across the myocardium, as well as longitudinal mechanical diastolic impairment, and prolonging duration of circumferential mechanical relaxation.