“A Study on Occurrence, Risk Factors and Cardiovascular Event Associated with Qt Interval Prolongation and Increased Dispersion in Newly Diagnosed Hypertension Patients”

Abstract

Background: Systemic hypertension is a widely prevalent non-communicable disease in India, impacting approximately 21–25% of the population. It is commonly linked to cardiovascular complications and target organ damage. Notably, changes in cardiac electrical activity, such as QT interval prolongation and increased dispersion, serve as important indicators associated with arrhythmias and sudden cardiac death. However, there is limited data on these parameters in patients newly diagnosed with hypertension.

Aim: This study aimed to determine the occurrence and risk factors associated with QT interval prolongation and increased dispersion in newly diagnosed hypertensive patients.

Materials and Methods: An observational cross-sectional study was conducted at Aarupadi Veedu Medical College, Puducherry, over an 18-month period. A total of 140 consecutive patients, newly diagnosed with hypertension based on JNC 8 guidelines (mean age 49.2 years; 58.6% male; 22.1% smokers), were enrolled. Comprehensive demographic, anthropometric, and biochemical data were collected. Electrocardiograms (ECGs) were performed, and the QT interval was measured using Bazett’s formula. Cardiovascular risk was further evaluated using the Framingham Risk Score (FRS).

Results: QT prolongation was present in 65.7% of cases, with 65% of patients exhibiting an FRS >1%. Notably, male patients showed a significantly higher incidence of both QT prolongation (73.2% vs. 55.2%) and elevated FRS (76.8% vs. 48.3%) compared to females (p<0.05). In patients with QTc prolongation, an FRS >1% was found in 85% of males and 68.8% of females, while among smokers, a significantly higher association was observed in males (52.9% vs. 18.2%, p<0.05).

Conclusion: The study demonstrates a high occurrence of QT interval prolongation in newly diagnosed hypertensive patients, particularly among males and smokers. Early risk stratification and targeted interventions are recommended to mitigate future cardiovascular events.