Improved glycemic control induces regression of left ventricular mass in patients with type 1 diabetes mellitus

Background: Diabetes mellitus has been associated with abnormalities of cardiac function and left ventricular hypertrophy. We sought to determine whether improved glycemic control in patients with type 1 diabetes mellitus will induce reversal of those abnormalities. Methods: We prospectively studied 19 patients (mean age 40±9 years) with longstanding type 1 diabetes mellitus (28±4 years), who participated in a program of stringent glycemic control. Glycemic control was monitored with hemoglobin A1c levels, and improvement was defined as >1% (absolute) decrease of hemoglobin A1c. Two-dimensional and Doppler echocardiograms and ambulatory 24-h blood pressures were obtained at baseline and after 1 year. Left ventricular mass was determined using the area-length method. Results: In the patients with improved glycemic control (n=12), hemoglobin A1c decreased from 9.8% to 7.8% (p≤0.0001), interventricular septal thickness decreased from 10.3 to 9.4 mm (p≤0.05), and left ventricular mass regressed from 205 to 182 g (p≤0.05). Septal thickness and left ventricular mass remained unchanged in the patients who did not achieve improvement of glycemic control. Left ventricular internal diameters, posterior wall thickness, fractional shortening, E/A ratio of mitral inflow, E-wave deceleration time (DT), and ambulatory 24-h blood pressures did not change significantly after 1 year in either group. Conclusions: Improved glycemic control in patients with type 1 diabetes mellitus is associated with regression of septal thickness and left ventricular mass without significant effect on systolic or diastolic function, in the absence of significant alterations in ambulatory 24-h blood pressures.