ABSTRACT
The QTc prolongation is a condition that predisposes for cardiac arrhythmias and is associated with a high mortality even in apparently healthy population. The aim of the study was to investigate the effect of acute hyperglycaemia on QTc, QTc dispersion in healthy subjects. 20 healthy subjects [10 males and 10 female] underwent hyperglycaemic clamp by quickly raising plasma glucose concentration to 270 mg/dl and maintaining this level for 2 hours. The same subjects, on another occasion, underwent the same hyperglycaemia clamp with octreotidesomatostatin analogue-infusion to block the release of endogenous insulin. Systolic and diastolic blood pressure, heart rate plasma, catecholamine concentrations, QTc and QTc dispersion showed significant increase at 120 minutes of the hyperglycaemic clamp. Octreotide infusion did not influence QTc duration. QTc dispersion and the haemodynamic effects of acute hyperglycaemia. Our results confirm that acute hyperglycaemia produces significant increments of QTc and QTc dispersion in normal subjects and endogenously released insulin is suggested to have no significant or pivotal role