Abstract
Background Mitral regurgitation (MR) is a major contributor for heart failure (HF) and atrial fibrillation. Despite the advancement of MR surgeries, an effective medical therapy to mitigate MR progression is lacking. Sodium glucose cotransporter 2 inhibitors, a new class of antidiabetic drugs, has shown measurable benefits in reduction of HF hospitalization and cardiovascular mortality but the mechanism is unclear. We hypothesized that dapagliflozin (DAPA), a sodium glucose cotransporter 2 inhibitor, can improve cardiac hemodynamics in MR-induced HF. Methods and Results Using a novel, mini-invasive technique, we established a MR model in rats, in which MR induced left heart dilatation and functional decline. Half of the rats were randomized to be administered with DAPA at 10 mg/kg per day for 6 weeks. After evaluation of electrocardiography and echocardiography, hemodynamic studies were performed, followed by postmortem tissue analyses. Results showed that DAPA partially rescued MR-induced impairment including partial restoration of left ventricular ejection fraction and end-systolic pressure volume relationship. Despite no significant changes in electrocardiography at rest, rats treated with DAPA exhibited lower inducibility and decreased duration of pacing-induced atrial fibrillation. DAPA also significantly attenuated cardiac fibrosis, cardiac expression of apoptosis, and endoplasmic reticulum stress-associated proteins. Conclusions DAPA was able to suppress cardiac fibrosis and endoplasmic reticulum stress and improve hemodynamics in an MR-induced HF rat model. The demonstrated DAPA effect on the heart and its association with key molecular contributors in eliciting its cardio-protective function, provides a plausible point of DAPA as a potential strategy for MR-induced HF.