Abstract
Radionuclide ventriculography was made in 49 asymptomatic diabetic patients, aged 30-70 years, to investigate cardiac function. Comparisons were made with 33 age- and sex-matched non-diabetic controls.
Radionuclide ventriculography was performed at rest and during dynamic exercise by multigraded, supine bicycle ergometer. The resting left ventricular ejection fractions were similar between the diabetic patients and control subjects. No significant rise in the left ventricular ejection fractions during dynamic exercise was observed in the diabetic patients [58.4±9.8% (mean±SD) to 60.3±9.9] . In the control subjects, the left ventricular election fractions increased during dynamic exercise [59.3±8.4 to 63.0±11.4 (p<0.05) ]. Peak ejection rates were similar in both groups at rest [-2.62±0.64 (s-1) vs-2.66±0.52] and during dynamic exercise [-3.25±0.74 vs-3.23±0.90] . Time to end-systole were similar in both groups at rest [315±42 (ms) vs 309±42] and during dynamic exercise [258±37 vs 262±37]. The resting peak filling rates were similar in both groups [2.27±0.62 (s-1) vs 2.45±0.58], and the peak filling rates increased (p<0.001) during dynamic exercise in both groups [2.68±0.61 vs 3.28±0.74] . However, the percent changes of the peak filling rates were significantly lower in diabetic patients (p<0.001). In four of the diabetic patients, hypokinesis of the intraventricular septum was observed. No relation was indicated between the percent changes of the left ventricular ejection fraction and the value of HbA1c in the diabetic patients. These results suggest that diabetic patients have less cardiac reserved performance.
