Cardiac Autonomic Neuropathy- An ECG Correlation in Type 2 Diabetes

Abstract

BACKGROUND Cardiac autonomic neuropathy is a serious complication with poor prognosis in type 2 diabetes. It is asymptomatic in diabetes. It results in increased incidence of silent myocardial infarction and ischemia and left ventricular dysfunction. Diabetic cardiac autonomic neuropathy (CAN) a serious microvascular complication with poor prognosis. Diabetic cardiac autonomic neuropathy (CAN), a major complication seen in one-sixth of insulin dependent type 1 diabetes and one-third of non-insulin dependent diabetic patients, is related with increased morbidity. We wanted to study the ECG and ECHO changes in type 2 diabetes to diagnose cardiac autonomic neuropathy. METHODS This was a case control study and sample size was taken for convenience. Patients attending diabetes and medical OPD in a teaching hospital were selected according to inclusion and exclusion criteria. Hundred patients of type 2 diabetes mellitus of more than five years duration and 100 age and sex matched controls without any history of diabetes were selected. ECG and ECHO were done in all cases and controls. RESULTS A total of 100 type 2 diabetes patients and 100 age matched controls were studied. QTc interval prolongation occurs with development of CAN. Prolongation of QTc interval is well correlated with Cardiac Autonomic Neuropathy in type 2 diabetes. CONCLUSIONS QTc interval is easily measurable and is a non-invasive method. It is the earliest sign of cardiac autonomic neuropathy. It is prolonged in type 2 diabetes patients with severe cardiac autonomic dysfunction. They have a high risk of developing silent myocardial infarction and sudden death. Early diagnosis and early control of sugar will prevent morbidity in diabetic individuals.

Survey on electrocardiography signal analysis and diabetes mellitus: unraveling the complexities and complications

“…e. Impact of QT and QTc interval: In gestational diabetes mellitus and CAN (with DM) individuals, nonsignificant lengthening of QT and QTc is found [16], [21], causing tachycardia. Prolonged QT interval causes diabetic autonomic neuropathy, which is the cause of silent death/myocardial infarction and cerebrovascular mortality [14], [22]. f. Impact of QRS and QT interval: For a normal person, during Tachycardia (shortening of QRS complex) there is a shortening of QRS [13].…”