comparison of (T_p-T_e)/(QT_C ) interval ratio and Tp-Te interval changes between administration of thrombolytics and performing ppci in patients with Anterior STEMI
Abstract
Anterior STEMI is associated with a high incidence (20% -25%) of ventricular fibrillation and SCD in its early stages. Tp-Te / QT ratio and Tp-Te / QTc ratio are recently used as arrhythmogenesis electrocardiographic indices. Few studies have been done on these two indices, which makes the need to study them more. Evidence from recent studies suggests that the Tp-Te interval is associated with ventricular repolarization dispersion. The importance of comparing the modalities and extent of these repolarization indices after two different treatment modalities - thrombolytic administration and PPCI - is crucial to find a better and preferred method for clinical use to improve outcome and reduce the incidence of arrhythmias and mortality. Therefore, the purpose of this study was to find out the differences between the two treatments in patients with Anterior STEMI.
Materials and Methods: 188 patients with anterior STEMI diagnosis were enrolled. 93 patients were treated with retplase and 95 were treated with PPCI. Changes in Tp-Te / QT ratio and Tp-Te / QTc ratio in ECG of patients were evaluated before and after PPCI or retaplase administration. The modified QT interval (QTc interval) is calculated using the Bazzet formula. Descriptive and analytical statistical analysis was performed using SPSS version 22 software.
Results: In this study, 202 patients were enrolled and 14 patients were excluded due to LVH and 118 patients with mean age of 58.97 years with standard deviation of 9.93. Of these, 72 (38.3%) were men and 116 (61.7%) were women. 95 (50.5%) patients were treated with PPCI and 93 (49.5%) patients received thrombolytic therapy (r-TPA). The Tp-Te / QT and Tp-Te / QTc ratios of the patients at the time of study were 27.11 3 3.7 and 24.91 67 3.67, respectively. These ratios after treatment were 23.93 66 3.66 and 21.91 23 3.23, respectively. Data analysis showed a significant difference between Tp-Te / QT ratios before and after treatment in both groups (P-value = 0.001 in both groups) before treatment of both Tp-Te / QT and Tp-Te ratios. / QTc were similar in both groups (P-value for Tp-Te / QTc = 0.72, for Tp-Te / QTc = 0.75). However, after treatment, PPCI group showed a more significant decrease than r-TPA group in Tp ratios. -Te / QT and Tp-Te / QTc (P-value = 0.001).