In a trial to evaluate the effects of diabetic autonomic neuropathy on the heart, This study comprised two groups ofnon insulin dependent diabetic patients. Each group included twenty patients, patients of the first group had symptoms and signs suggestive of autonomic neuropathywhile those of the second groupwere free fromsuch symptoms and signs. Simple non invasive testswere done to confirmthe diagnosis, a third group of twenty normal subjects was taken as a control group. Every subject in the study was subjected to fasting and-two hours post prandial blood sugar level, twelve leads surface ECG, leadnrhythm strip during and after valsalva maneuver, serumpotassiumand calciumlevels.
We found that diabetic patientswith autonomic neuropathy had higher incidence of resting tachycardia, prolonged PRinterval, ST segment and T
wave changes and prolonged QTc interval. Therewas also a significant el evation of serumpotassiumand lowering of serumcalciumin diabetics
with autonomic neuropathymore than in diabeticswithout neuropathy.No changes in serumcalciumlevel between diabeticswithout neuropathy and normal control subjectswas observed. Cardiac autonomic neuropathymay prove to be an importantmechanismin the pathogenesis of arrhythmias and sudden death. In diabetes prolongedQTc intervalmay be amarker for prospective identification of such arrhythmias. |
