Dapagliflozin is associated with a reduction in left atrial volume index in type 2 diabetes mellitus without established cardiovascular disease

Diabetic cardiomyopathy (DCM) frequently begins with diastolic dysfunction (DD), which leads to increased left ventricular filling pressures and subsequent left atrial enlargement, quantified by the left atrial volume index (LAVI). SGLT-2 inhibitors have demonstrated cardioprotective benefits extending beyond glycemic control; however, their specific impact on early cardiac structural remodeling in DCM remains incompletely understood. This single-center, prospective observational study enrolled 36 patients with type 2 diabetes mellitus (T2DM) who were initiated on dapagliflozin (10 mg once daily). Thirty-five patients completed 6-month follow-up. Transthoracic echocardiography, exercise ECG testing, and comprehensive laboratory analyses were performed at baseline and at 6 months. LAVI decreased significantly over 6 months during dapagliflozin treatment (31.7 ± 10.6 vs. 27.9 ± 10.6 ml/m², p < 0.01). Interventricular septum and posterior wall thicknesses were significantly reduced ( p < 0.01). Descriptive subgroup patterns were observed: LAVI decrease was statistically significant in asymptomatic patients without clinical heart failure (baseline LAVI < 34 ml/m²), whereas a numerical decrease in the heart failure subgroup did not reach statistical significance; no formal interaction testing was performed. HDL cholesterol increased significantly (46.0 ± 7.4 vs. 48.2 ± 8.1 mg/dL, p = 0.03), while AST and ALT levels declined significantly. Exercise duration and maximum METs improved significantly ( p < 0.01). Resting heart rate decreased from 78.0 ± 15.4 to 71.2 ± 13.3 bpm ( p < 0.01). LAVI was significantly lower at 6 months compared to baseline in T2DM patients during dapagliflozin treatment, consistent with a possible association with early structural changes in diabetic cardiomyopathy. Given the uncontrolled, single-arm design, causality cannot be inferred; these findings are hypothesis-generating and require confirmation in randomized controlled studies. Secondary exploratory findings, including improved exercise capacity, reduced resting heart rate, raised HDL cholesterol, and improved hepatic enzyme profiles, should likewise be interpreted with caution. Over 6 months of dapagliflozin treatment, left atrial volume index and early cardiac structural indices were significantly lower at follow-up in type 2 diabetes patients free of established cardiovascular disease. A descriptive subgroup pattern was observed in asymptomatic patients without clinical heart failure; no formal interaction testing was performed. Accompanying observations included improved diastolic function indices, reduced resting heart rate, and favourable metabolic changes. All findings are hypothesis-generating and require confirmation in randomized, controlled studies.