Evaluation of Tp-e interval and Tp-e/QT ratio in patients with ankylosing spondylitis.

Abstract

OBJECTIVES: Ankylosing spondylitis (AS) is a chronic multi-systemic inflammatory rheumatic disorder. Several studies have suggested that the interval from the peak to the end of the electrocardiographic T wave (Tp-e) may correspond to the transmural dispersion of repolarization and that increased Tp-e interval and Tp-e/QT ratio are associated with malignant ventricular arrhythmias. The aim of this study was to evaluate ventricular repolarization by using Tp-e interval and Tp-e/QT ratio in patients with AS, and to assess the relation with inflammation. METHODS: Sixty-two patients with AS and 50 controls were included. Tp-e interval and Tp-e/QT ratio were measured from a 12-lead electrocardiogram, and the Tp-e interval corrected for heart rate. The plasma level of high sensitive C-reactive protein (hsCRP) was measured. These parameters were compared between groups. RESULTS: In electrocardiographic parameters analysis, QT dispersion (QTd) and corrected QTd were significantly increased in AS patients compared to the controls (31.7±9.6 vs 28.2±7.4 and 35.8±11.5 vs 30.6±7.9ms, P=0.03 and P=0.007, respectively). cTp-e interval and Tp-e/QT ratio were also significantly higher in AS patients (92.1±10.2 vs 75.8±8.4 and 0.22±0.02 vs 0.19±0.02ms, all P values <0.001). cTp-e interval and Tp-e/QT ratio were significantly correlated with hsCRP (r=0.63, P<0.001 and r=0.49, P<0.001, respectively). CONCLUSIONS: Our study revealed that Tp-e interval and Tp-e/QT ratio were increased in AS patients. These electrocardiographic ventricular repolarization indexes were significantly correlated with the plasma level of hsCRP.