Prolonged Tp-e Interval, Tp-e/QT Ratio and Tp-e/QTc Ratio in Patients with Type 2 Diabetes Mellitus

BACKGROUND: Type 2 diabetes mellitus (T2DM) is associated with increased risk of malignant ventricular arrhythmias. Cardiac electrical inhomogeneity may be the leading cause of the increased arrhythmic risk in patients with T2DM. The peak and the end of the T wave (Tp-e) interval and associated Tp-e/QT ratio are promising measures of ventricular repolarization indicating transmural dispersion of repolarization. The aim of this study was to assess ventricular repolarization in patients with T2DM by using Tp-e interval, Tp-e/QT ratio and Tp-e/corrected QT interval (QTc) ratio. METHODS: Forty-three patients with T2DM and 43 healthy control subjects, matched by gender and age, were studied. All participants underwent electrocardiography (ECG) recording. PR, RR and QT intervals represents the ECG intervals. These are not abbreviations. In all literature these ECG intervals are written like in this text. Tp-e intervals were measured from 12-lead ECG. Rate QTc was calculated by using the Bazett's formula. Tp-e/QT ratio and Tp-e/QTc ratio were also calculated. RESULTS: Mean Tp-e interval was significantly prolonged in patients with T2DM compared to controls (79.4±10.3, 66.4±8.1 ms, respectively; P<0.001). We also found significantly higher values of Tp-e/QT ratio and Tp-e/QTc ratio in patients with diabetes than controls (0.21±0.03, 0.17±0.02 and 0.19±0.02, 0.16±0.02, respectively; P<0.001). There was no difference in terms of the other ECG parameters between the groups. CONCLUSION: Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio were prolonged in patients with T2DM. We concluded that T2DM leads to augmentation of transmural dispersion of repolarization suggesting increased risk for ventricular arrhythmogenesis.

CHA[2]DS[2] -VASc score as a predictor of left atrial thrombus in patients with non-valvular atrial fibrillation

To investigate whether or not the CHA[2]DS[2] -VASc score predicts left atrial [LA] thrombus detected on pre-cardioversion transoesophageal echocardiography [TEE]. The medical records of patients who had undergone TEE were reviewed to assess the presence of LA thrombus prior to direct-current cardioversion for atrial fibrillation [AF]. The CHA[2]DS[2] -VASc score was calculated for each patient. Clinical TEE reports were reviewed for the presence of LA thrombus. Patients with a valve prosthesis or rheumatic mitral valve disease were excluded from this study. A total of 309 patients were identified. The mean age was 70.1 +/- 9.8 years and 151 [49%] patients were males and 158 [51%] were females. LA thrombus was seen in 32 [10.3%] of the 309 patients. Fifty [16.2%] patients had a low CHA[2]DS[2] -VASc score [0-1], 230 [74.4%] had an intermediate score [2-4] and 29 [9.4%] had a high score [5-9]. The incidence of LA thrombus in the low, intermediate and high CHA[2]DS[2] -VASc score groups was 0, 4.4 and 68.7%, respectively. The LA thrombus risk increased with increasing CHA[2]DS[2] -VASc scores. On multivariate logistic analysis, the CHA[2]DS[2] -VASc score [OR 3.26, 95% CI 2.3-4.65; p = 0.001] and age [OR 0.93, 95% CI 0.88-0.98; p = 0.004] were independent risk factors for LA thrombus in patients with non-valvular AF. A high CHA[2]DS[2] -VASc score was independently associated with the presence of LA thrombus in patients with non-valvular AF