Impact of Aortic Valve Replacement on Glycemic Control in Diabetes Mellitus

The Framingham Studies revealed that diabetes mellitus (DM) predisposed subjects to a two- to eight-fold increase in the risk of developing heart failure (HF). However, there is much less information available about the reverse issue; namely, whether there is an increased risk of developing DM in patients with HF. We sought to determine if reversal or partial reversal of HF through aortic valve replacement (AVR) would improve glycemic control in patients with DM at our institution. The electronic medical records of 57 consecutive diabetic patients were retrospectively analyzed. These patients had undergone AVR at a medium-sized academic medical center from May 2005 through May 2015, and had glycated hemoglobin (HbA1C) measured before and after the procedure. The variables of interest included HbA1C, and echocardiographic parameters such as left ventricular ejection fraction (LVEF), tricuspid regurgitation velocity (TRV), and right ventricular systolic pressure (RVSP) before and after valve replacement. HbA1C decreased significantly during the first year after replacement, from 7.1% (range 4.4 - 13.0%) before surgery to 6.5% in the first year (P < .05). In addition, the calculated RVSP decreased from 44 mmHg (20 - 79 mmHg) to 37 mmHg (P < .05 from the preoperative value). LVEF and TRV did not change significantly. Reductions in HbA1C and RVSP during the first year were greater in patients who experienced an increase of 5% or more in EF at their first postoperative measurement. Patients with higher baseline HbA1C values had a greater decline in glycated Hb during the first year (P < .01). AVR was associated with a reduction of HbA1C and a decrease in pulmonary artery systolic pressure within one year of the procedure.