Left ventricular dysfunction in normotensive type II diabetic patients in Port Harcourt, Nigeria

Diabetes mellitus (DM) is on the increase globally. Cardiovascular complications, such as left ventricular dysfunction is a major cause of death in patients with type II DM. Prior to the development of symptomatic heart failure, subclinical left ventricular dysfunction (systolic and diastolic) may exist for some time.

The aim of the study was to determine the prevalence of left ventricular dysfunction in non-hypertensive type II DM patients.

A cross sectional study of left ventricular function in 90 normotensive type II diabetes mellitus patients using echocardiography was carried out. Healthy normotensive controls matched for age, sex, and body mass index were selected for comparison. Patients and controls who had hypertension (blood pressure of >140/90 mmHg), history of smoking, significant alcohol history, pregnancy, features of thyroid disease, or valvular heart disease were excluded. Left ventricular diastolic and systolic functions were assessed.

Ninety patients, (39 males and 51 females) and 90 healthy controls (39 males and 51 females) were enrolled. Mean age of patients was 50.76 ± 9.13 years and 51.33 ± 7.84 years for controls. Mean body mass index was 26.88 ± 4.73 kg/m² in patients and 27.09 ± 4.04 kg/m² in controls. Mean ejection fraction was 62.4% ± 8.47% and 68.52% ± 7.94% in patients and controls, respectively (P < 0.001). Fourteen (15.56%) patients had ejection fraction less than 55% compared to four (4.44%) in controls (P < 0.001; odds ratio = 3.96). Impaired diastolic function was found in 65.6% of patients compared to 3.3% of controls (P < 0.001). Left ventricular mass index of >99 kg/m² in females and >115 kg/m² in males was considered abnormal. The left ventricular mass index was also higher in patients than in controls (95.17 ± 25.67 g/m² versus 85.40 ± 18.0 g/m²; P = 0.004).

Normotensive diabetic patients have a high prevalence of left ventricular dysfunction even in the absence of cardiac symptoms.