Subclinical right ventricular dysfunction in patients with asymptomatic type 2 diabetes mellitus: A cross-sectional study.

Background: Diabetic cardiomyopathy, which involves both the right and left ventricles, progresses from a preclinical stage to overt heart failure. Detection of this entity at a preclinical stage could be crucial in intervening to halt its progression to overt heart failure. There is a paucity of literature on subclinical RV dysfunction in diabetic patients, and it is even rarer in the Indian literature. Our study intended to study this clinical entity through an echocardiographic assessment of asymptomatic patients.

Objectives: This was a cross-sectional observational analytic study, comparing subclinical RV dysfunction in diabetic and non-diabetic subjects by using echocardiography as a primary objective, while the secondary objective of the study was to find out the correlation between RV dysfunction and the duration of diabetes mellitus and HbA1C levels.

Methods: Conventional echocardiography with tissue Doppler imaging (TDI) was used to measure nine different echocardiographic parameters in the diabetic and non-diabetic groups. All probable causes of RV dysfunction were excluded before enrolling the patients in the study. Unpaired t-test was used to compare the parameters between the two groups, and multivariate regression analysis was done taking into consideration age, duration of diabetes, and HbA1C levels as the independent variables, and echocardiographic parameters as the dependent variables.

Results: Out of the nine different echocardiographic parameters, Tricuspid annular plane systolic excursion (TAPSE), RV end diastolic diameter (RVEDD), Tricuspid peak late diastolic velocity (A), E/A ratio, RV basal segment peak myocardial systolic velocity (Sm), RV basal segment peak early diastolic velocity (Em), RV basal segment peak late diastolic velocity (Am), and E/Em ratio showed statistically significant differences between the two groups. These results show the presence of subclinical RV dysfunction in diabetic patients. TAPSE and E/A ratio showed a significant correlation with the duration of diabetes, while Em showed a significant correlation with HbA1C.

Conclusion: Diabetes mellitus is associated with subclinical systolic as well as diastolic RV dysfunction. In addition to helping identify people at high risk, the early recognition of RV dysfunction gives us a window of opportunity to take action and slow down the disease's course. This study emphasizes that the early identification of RV diastolic as well as systolic dysfunction in asymptomatic Type 2 diabetic patients can be a helpful tool in halting the progression of disease from subclinical to frank clinical cases, thereby preventing the morbidity and mortality associated with heart failure. Hence, it adds value to the pre-existing literature.