Abstract
Background: There is a direct relation between blood pressure and cardiovascular risk. In addition, QT interval prolongation is associated with increased rate of cardiovascular morbidity and mortality. Thus, it is wise to investigate the correlation of blood pressure and QT interval to find out the risk of sudden death in individuals with increase in blood pressure.

Aims and Objectives: The aim of the present study was to see the effect of blood pressure on the QT corrected interval.

Materials and Methods: This study included 48 healthy men and 32 healthy women between 17 and 68 years age divided into three groups, young (<30 years), middle aged (30-60 years) and elderly (>60 years). The heart rate, systolic, and diastolic blood pressure and mean arterial pressure (MAP) were recorded and a standard supine 12 lead electrocardiographic was done. The individuals were categorized for QTc prolongation, into three gender-specific categories. For women, the cutoff points were ≤450 ms (normal), 451-470 ms (borderline), and >470 ms (prolonged), and for men ≤430 ms (normal), 431-450 ms (borderline), and >450 ms (prolonged).

Results: Out of the eighty individuals taken for the study, 48 individuals (60%) were males and 32 (40%) were females. The MAP (in mm of Hg) was 87.8 ± 4.5 in young age group, 89.5 ± 5.8 in middle-aged group, and 97.7 ± 5.4 in elderly age group. QTc was found to be 374.9 ± 31 (ms) in young group, 386.3 ± 14.8 (ms) in middle-aged group, and 414.5 ± 11.8 (ms) in old age group.

Conclusion: MAP correlated most with the QTc interval (r = 0.327) and was an important predictor of QT and QTc interval.

Key words: Blood Pressure; Diastolic Blood Pressures; Mean Arterial Pressure; QT; QTc; Systolic Blood Pressure