Abstract
BACKGROUND: Left ventricular (LV) involvement in diabetic cardiomyopathy has been reported; however, only limited data exist on right ventricular (RV) involvement. Therefore, our purpose was to investigate RV systolic dysfunction and its association with LV longitudinal myocardial dysfunction in patients with type 2 diabetes mellitus (T2DM) and preserved LV ejection fraction (LVEF). METHODS: We studied 177 T2DM patients with preserved LVEF and 79 age-, sex-, and LVEF-matched healthy volunteers. LV longitudinal myocardial function was assessed as global longitudinal strain (GLS), and RV systolic function was assessed as RV free-wall strain, and predefined cutoff values for subclinical dysfunction were set at GLS < 18% and RV free-wall strain < 20%, respectively. RESULTS: RV free-wall strain in T2DM patients was significantly lower than that in normal controls (19.3% ± 4.8% vs. 24.4% ± 5.1%; P < 0.0001). RV free-wall strain in T2DM patients and LV longitudinal dysfunction was similar compared to that in T2DM patients without (19.0 ± 4.5% vs. 19.6 ± 5.0%, P = 0.40). Furthermore, multivariate logistic regression analyses showed that GLS was independently associated with RV systolic dysfunction as well as mitral inflow E and mitral e' annular velocities ratio (odds ratio, 1.16; 95% confidence interval: 1.03-1.31; P < 0.05). Sequential logistic models evaluating the association of RV systolic dysfunction in T2DM patients showed an improvement in clinical variables (χ(2) = 6.2) with the addition of conventional echocardiographic parameters (χ(2) = 13.4, P < 0.001) and a further improvement with the addition of GLS (χ(2) = 20.8, P < 0.001). CONCLUSION: RV subclinical systolic dysfunction was observed in T2DM patients with preserved LVEF and was associated with LV longitudinal myocardial dysfunction. Our findings may provide additional findings for the management of T2DM patients.