Association of Glycemic Control With Right Ventricular Function Assessed by Two-Dimensional Speckle-Tracking and Three-Dimensional Echocardiography in Type 2 Diabetes Mellitus

BACKGROUND: Right ventricular (RV) involvement has been reported in type 2 diabetes mellitus (T2DM). The relationship between glycemic control and RV function remains unknown. We aimed to investigate the association between glycemic control and RV function assessed by two-dimensional speckle-tracking echocardiography and three-dimensional echocardiography in T2DM individuals. METHODS: This study prospectively enrolled 207 patients with T2DM and 84 individuals with normal glucose metabolism. The T2DM patients were divided into 2 subgroups according to glycated hemoglobin (HbA1c) level: controlled (HbA1c < 7.0%, n = 91) and uncontrolled subgroup (HbA1c ≥ 7.0%, n = 116). Right venticular free wall longitudinal strain (RVFWLS) was acquired by two-dimensional speckle-tracking echocardiography, and RV volumes and RV ejection fraction (RVEF) were assessed using three-dimensional echocardiography . Right ventricular coupling to pulmonary circulation was defined as the ratio of RVFWLS/pulmonary artery systolic pressure (PASP). RESULTS: Controlled and uncontrolled T2DM subgroups had impaired RV function as reflected by reduced RVFWLS and RVEF compared to the normal glucose metabolism group. The reduction in RVFWLS was more pronounced in the uncontrolled subgroup than in the controlled subgroup (P < .001), whereas no significant difference was found in RVEF between these 2 T2DM subgroups. Higher PASP and lower RVFWLS/PASP ratio were also noted in uncontrolled T2DM patients. Additionally, the incidence of RV dysfunction was significantly higher in the uncontrolled T2DM patients than in the controlled subgroup (43.1% vs 17.6%, P < .001). After adjustment for potential clinical confounders, PASP, and left ventricular parameters, HbA1c level was independently associated with RVFWLS (β = 0.290, P = .003) and RVFWLS/PASP ratio (β = 0.028, P = .006). CONCLUSIONS: Subclinical RV myocardial dysfunction is present in T2DM patients and is more pronounced in patients with uncontrolled blood glucose. HbA1c level is independently associated with subclinical RV myocardial dysfunction, providing further insight into a possible link between poor glycemic control and diabetic cardiomyopathy.