ECHOCARDIOGRAPHIC ASSESSMENT OF LEFT VENTRICULAR FUNCTION IN PATIENTS WITH TYPE 2 DIABETES MELLITUS AT UBTH, BENIN CITY.
BACKGROUND: Myocardial dysfunction may occur in patients with diabetes mellitus in
the absence of hypertension, coronary artery disease or valvular heart disease. The
mechanisms underlying this diabetic cardiomyopathy are largely unknown, but may involve
altered myocardial energy metabolism. The mechanisms that have been postulated include
microangiopathy, autonomic nervous dysfunction, defective cellular calcium transport, as
well as structural changes in myocardial contractile proteins and accumulation of collagen,
leading to increased stiffening of the ventricular wall.
AIM: To assess left ventricular function in patients with type 2 diabetes mellitus and
compare with normal population.
METHOD: A total of Two hundred and forty five type 2 diabetes mellitus patients were
recruited alongside eighty one control subjects who were matched for age and sex.
Anthropometric parameters were recorded and subjects had investigations which included
fasting plasma glucose, haemoglobin A1C, fasting lipid profile, electrocardiography and
echocardiography. Analysis of data was done using the Statistical Package for Social
Sciences (SPSS) Software version 20.
RESULT: The mean age of the diabetic subjects (51.14±7.04 years) was similar to that of
the control (49.91±7.91 years) (P=0.189). The mean duration of diabetes mellitus was
6.87±4.08 years. Systolic function was within normal in all subjects. The mean ejection
fraction (EF) was significantly lower in the diabetic subjects (EF: 61.09±6.49% vs.
63.8±5.93%, P=0.001). Diastolic dysfunction was found more in the diabetic subjects
(61.2%) compared to the controls (13.6%). The mean E/A was significantly higher in the
control group (1.21±0.37 vs. 1.02±.37, P<0.0001). The mean deceleration time (DT) was
significantly higher in the diabetic group (214.07±32.47ms vs. 204.98±27.35ms, P=0.014).
The mean IVRT was significantly higher in the patient group (88.97±12.96 vs. 83.56±10.7,
P<0.0001). The E/e′ was significantly higher in the diabetics compared to the controls
(8.06±2.75 vs. 6.93±1.95, P<0.0001). The S/D was higher in the controls than the diabetics,
though not statistically significant. The ArV (atrial systolic reversal velocity) and Ar-A
(difference in duration between Ar and mitral A-wave) were higher in the diabetics and
statistically significant (P<0.0001). Diastolic dysfunction significantly correlated positively
with age of the patient, duration of DM, BMI, WHR, SBP and DBP. Diastolic dysfunction
correlated negatively with HbA1C (glycaemc control) but was not statistically significant..
The LVMI was significantly higher in the diabetics compared with the control
(105.69±19.85g/m2 vs. 95.84±18.76g/m2, P<0.0001). The LVMI correlated positively with
age of the patient, duration of DM, BMI, WHR, SBP and DBP.
CONCLUSION: Diastolic dysfunction is common in type 2 diabetes mellitus patients and
appears to be related to the duration of diabetes and glycaemic control.