Assessment of left ventricular functions in patients with type 2 diabetes mellitus using tissue Doppler imaging and its correlation with a novel cardiac biomarker

Abstract

Introduction Cardiovascular diseases account for about 65% of diabetes-related mortality. Objective Noninvasive assessment of left ventricular functions in asymptomatic nonhypertensive nonischemic type 2 diabetics using echo heart and tissue Doppler imaging (TDI) for detecting structural and functional cardiac abnormalities, and correlating them with levels of Brain natriuretic peptide (BNP) for early planning of management before passing into overt heart failure (HF) were the objectives of this study. Patients and methods We studied 55 patients with type 2 diabetes and classified them into two groups: 26 patients with less than 10 years diabetes duration and 29 patients with more than 10 years duration. Full history, fasting blood glucose, postprandial blood glucose, glycated hemoglobin, creatinine, lipid profile, BNP, ECG, conventional echo, and TDI were performed for all patients. Results In all, 45 (80%) patients out of 55 patients have diastolic dysfunction, classified as 15 (27%) with type 1 diastolic dysfunction, 26 (47%) with type 2 pseudonormal diastolic dysfunction, and four (7%) patients with type 3 diastolic dysfunction. Systolic dysfunction (ejection fraction <55) was present in nine (16%) patients despite absent HF. BNP was significantly high in patients with longer diabetes duration (P=0.008). There was a statistically significant difference in the BNP level between those with diminished systolic function and those with normal systolic function, P=0.001; yet no statistically significant difference was found between BNP and different groups of diastolic dysfunction (P=0.7). Conclusion Diabetic cardiomyopathy is an important diabetes complication. It varies from subclinical ventricular dysfunction to overt HF. Echocardiography is the standard diagnostic tool for diabetic cardiomyopathy. TDI can be used to quantitatively assess global, regional, systolic, and diastolic myocardial functions. Plasma BNP can be a prognostic rather than diagnostic test.

Keywords

• brain natriuretic peptide
• cardiomyopathy
• diabetes mellitus
• diastolic dysfunction