Tpeak-Tend for arrhythmic or mortality risk stratification in Ischemic Heart Disease: a meta-analysis Ka Hou Christien Li 1, Mengqi Gong BS 2, Wing Tak Wong MPhil PhD 3, Paula Whittaker MBChB MPH MMed MRCGP 4, Guangping Li, MD, PhD 2, Tong Liu MD PhD 2, Gary Tse MBBS MA PhD FRSPH FESC FACC * 5 1 Faculty of Medicine, Newcastle University, Newcastle, United Kingdom 2 Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin 300211, People’s Republic of China 3 School of Life Sciences, Chinese University of Hong Kong, Hong Kong, SAR, P.R. China 4 Division of Population Health, Health Services Research and Primary Care, School of Health Sciences, University of Manchester, United Kingdom 5 Department of Medicine and Therapeutics, Faculty of Medicine, Chinese University of Hong Kong, Hong Kong, SAR, P.R. China; Li Ka Shing Institute of Health Sciences, Faculty of Medicine, Chinese University of Hong Kong, Hong Kong, SAR, P.R. China; School of Health Sciences, University of Manchester, United Kingdom BACKGROUND RESULTS Ischemic Heart Disease (IHD) is associated with an excess mortality attributable to malignant ventricular ventricular tachycardia/fibrillation (VT/VF), which can result in sudden cardiac death (SCD). A number of electrophysiological mechanisms, such as abnormal repolarization, have been implicated in its disease pathogenesis. Changes in the Tpeak – Tend interval derived from the electrocardiogram have been examined for ability to predict VT/VF and SCD in myocardial infarction. However, its predictive value in risk stratification has been disputed. 854 studies were initially identified from these databases, of which six studies were found to be relevant to IHD. A total of 3302 with a mean age of 61 ± 5 years old and 79 ± 5% male were included. The mean follow-up period was 20 ± 11 months. The mean cut-off point for Tpeak – Tend was 112.8 ± 23.1 ms. All six groups consistently reported a positive association between increased Tpeak – Tend and an increased risk of VF/VT or SCD. The pooled meta-analysis demonstrated that prolonged Tpeak – Tend interval was associated with approximately 1.06 times the risk of these endpoints (95% CI: 1.02 to 1.09, p = 0.001). I2 took a value of 89.6%, which suggests the presence of significant heterogeneity. OBJECTIVES A systematic review and meta- analysis was performed to evaluate the overall value of Tpeak – Tend in predicting both SCD and arrhythmic outcomes in patients with IHD. DISCUSSION Although the mechanism of the T-wave generation remains controversial, as to whether it represents global or transmural dispersion, prolonged Tpeak – Tend interval has been associated with increased incidences of ventricular tachyarrhythmias. Prolonged Tpeak – Tend theoretically increases arrhythmic risk because increased spatial dispersion of repolarization can produce unidirectional block, which predisposes to reentry. METHODS A systematic literature search was performed using PubMed, Embase, MEDLINE, Cochrane library and CINAHL Plus to identify relevant studies from the beginning of these databases up until November 2016. The inclusion criteria include human studies reporting hazard and/or odd ratios for VT, VF and SCD. All potentially relevant reports were retrieved as complete manuscripts and assessed for compliance with the inclusion criteria CONCLUSION This meta-analysis illustrates that Tpeak – Tend is a useful risk stratification marker in patients post-MI. As such, it should be used as a complementary marker for tachyarrhythmia risk stratification in a clinical setting.