Echocardiographic evaluation of right ventricular function in type-2 diabetic patients using 2-dimensional speckle tracking imaging

Abstract

Objective To evaluate right ventricular (RV) systolic function in type-2 diabetes mellitus (T2DM) patients. Methods Fifty T2DM patients and fifty normal controls were included in the study and underwent echocardiographic examinations. The following parameters were measured: 1) Right heart dimensions, pulmonary artery (PA) diameter, pulmonary acceleration time (AT) and PA systolic pressure (PASP); 2) RV systolic function: RV fractional area change (RVFAC), tissue Doppler-derived tricuspid lateral annular systolic velocity (S'), tricuspid annular plane systolic excursion (TAPSE), longitudinal strain of six RV segments by 2-dimensional speckle tracking imaging (2D-STI); 3) RV diastolic function: E, A ratio of the tricuspid inflow spectrum (E/A), E, E' (peak early diastolic velocity of the tricuspid annulus) ratio (E/E'); 4) RV Tei index. Results Statistic analysis showed that T2DM patients had thicker RV walls, wider PAs and shorter AT than the control group (P=0.000, 0.001 and 0.000), while their right heart chamber sizes and PASP remained unchanged. Among systolic parameters, absolute values of RV longitudinal strain at the lateral wall-mid (lat-m), septum-mid (sep-m) and septum-basal (sep-b) segments were significantly lower in the diabetic group than the control group (P=0.001, 0.000 and 0.005), whereas strain of the other three RV segments and RVFAC, TAPSE. S' were not significantly different. Moreover, E/A, E/E' and Tei index were all significantly different between the two groups (P=0.000, 0.000 and 0.006), indicating declined diastolic and general function of RV in the T2DM group. Conclusions RV myocardial strain by 2D-STI is more sensitive in detecting RV systolic dysfunction than TAPSE, S' and RVFAC. Among the six segments of RV walls, lat-m, sep-m and sep-b are better locations for 2D-STI than the other three. Key words: Echocardiography; Diabetes mellitus; Ventricular function, right; Strain