1. BACKGROUND AND OBJECTIVES
Tpeak-Tend for arrhythmic or mortality risk stratification in heart failure: a meta-analysis
Ka Hou Christien Li 1, Mengqi Gong BS 2, Wing Tak Wong PhD 3, Paula Whittaker MPH MMed MRCGP 4, Yat Sun Chan FRCP FACC 5, Bryan P Yan FESC FACC 5, Guangping Li, MD, PhD 2, Tong Liu MD PhD 2, Gary Tse PhD FESC FACC FRCP *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 , 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 AND OBJECTIVES
FIGURE
Heart Failure (HF) is commonly associated with an excess mortality attributable to malignant ventricular tachycardia/fibrillation (VT/VF), resulting in sudden cardiac death (SCD). A number of electrophysiological mechanisms, such as enhanced or suppressed automaticity, triggered activity and re-entry, have been implicated in its disease pathogenesis. Prolongations in the Tpeak – Tend interval derived from the electrocardiogram, a marker of repolarization dispersion, have been shown to predict VT/VF and SCD, but its predictive value in risk stratification has been disputed. 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 HF.
METHODS
DISCUSSION
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 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
Although the mechanism of the T-wave generation remains controversial, as to whether it represents global or transmural dispersion, prolonged Tpeak – Tend intervals have 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.
RESULTS
CONCLUSION
A total of 854 studies were initially identified from these databases, of which eight studies were found to be relevant to HF. A total of patients with a mean age of 65 ± 7 years old and 70 ± 11% male were included. The mean follow-up period was 21 ± 14 months. The mean cut-off point for Tpeak – Tend was ± 8.4 ms. All eight groups consistently reported a positive association between increased Tpeak – Tend and an increased risk of VT/VF or SCD. The pooled meta-analysis demonstrated that prolonged Tpeak – Tend interval was associated with approximately 1.07 times the risk of these endpoints (95% CI: 1.04 to 1.11, p < ). I2 took a value of 87.5%, suggesting most of the observed variance reflects heterogeneity between studies.
This meta-analysis illustrates that Tpeak – Tend is a useful risk stratification marker in patients with HF. As such, it should be used as a complementary marker for tachyarrhythmia risk stratification in a clinical setting.
FUNDING
Christien Li is awarded the Undergraduate Physiological Society UK Travel Grant for this presentation. GT is supported by a Clinical Assistant Professorship by the Croucher Foundation of Hong Kong.