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

Hisham Sharif, Stephen Ting, Lynsey Forsythe, Gordon McGregor, Prithwish Banerjee, Deborah O’Leary, David Ditor, Keith George, Daniel Zehnder, David Oxborough

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±0.2 l/s vs NDF 1.0±0.3 l/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, hhypertensive 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.