The Relationship of the LV Systolic Function, the LV Dimension and the LV Mass to QT Dispersion in Stable Angina Patients who are with or without Significant Coronary Stenosis

Kwon, Jong Bum; Yoon, Hee Jeoung; Jin, Seung Won; Her, Sung Ho; Kim, Hyung Doo; Kim, Kyung Soo; Lee, Jong Ho; Park, Khun

Abstract

BACKGROUND: The aim of this study was to investigate the relationship of the left ventricular (LV) systolic function, the LV dimension and the LV mass with the QT dispersion in patients with stable angina, and we also wanted to compare this relationship between patients with and without significant coronary stenosis on coronary angiography. MATERIAL AND METHOD: 174 patients complained of typical angina and they had no associated ST segment or cardiac enzyme abnormalities. The patients were divided into 2 groups based on the results of coronary angiography: the patients with angiographic coronary stenosis > or =50% made up group I (n=101), and the patients with angiographic coronary stenosis <50% made up group II (n=73). An echocardiogram for assessing the LV ejection fraction (EF), the LV dimension and the LV mass and a 12-lead electrocardiogram for assessing the QT dispersion were performed before the coronary angiography. RESULT: The QT dispersion was significantly greater in group I than that in group II (39.8 ms vs. 33.3 ms; p<0.05). For all the patients, all the parameters of LV dimension and LV mass had statistically positive correlation to the QT dispersion, but the LV mass was the only independently significant parameter that was correlated with the increased QT dispersion (p<0.05). For group I, none of the echocardiographic parameters had significant correlation with the QT dispersion. However, the LV dimension and LV mass had significantly positive correlation with the QT dispersion, and the LV mass was also the only independently significant parameter that was correlated with increased QT dispersion in group II (p<0.05). CONCLUSION: Our study demonstrated a significantly positive correlation of the QT dispersion to the LV dimension and the LV mass in patients with stable angina. These findings are present only in patients without significant coronary stenosis.