Gary Tse1,2, Sharen Lee3, Mengqi Gong4, Panagiotis Mililis5, Dimitrios Asvestas5, George Bazoukis5, Leonardo Roever6, Kamalan Jeevaratnam7, Sandeep S Hothi8, Ka Hou Christien Li9,4,10, Tong Liu4, Konstantinos P Letsas11. 1. Xiamen Cardiovascular Hospital Affiliated to Xiamen University, Xiamen, Fujian, People's Republic of China. gary.tse@doctors.org.uk. 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. gary.tse@doctors.org.uk. 3. Laboratory of Cardiovascular Physiology, Li Ka Shing Institute of Health Sciences, Hong Kong, SAR, People's Republic of China. 4. 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. 5. Second Department of Cardiology, Laboratory of Cardiac Electrophysiology, Evangelismos General Hospital of Athens, Athens, Greece. 6. Department of Clinical Research, Federal University of Uberlândia, Uberlândia, MG, Brazil. 7. Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK. 8. Heart and Lung Centre, New Cross Hospital, Wolverhampton, UK. 9. Xiamen Cardiovascular Hospital Affiliated to Xiamen University, Xiamen, Fujian, People's Republic of China. 10. Faculty of Medicine, Newcastle University, Newcastle, UK. 11. Second Department of Cardiology, Laboratory of Cardiac Electrophysiology, Evangelismos General Hospital of Athens, Athens, Greece. k.letsas@gmail.com.
Abstract
BACKGROUND: Brugada syndrome (BrS) is an ion channelopathy that predisposes affected subjects to ventricular tachycardia/fibrillation (VT/VF) and sudden cardiac death. Restitution analysis has been examined in BrS patients but not all studies have reported significant differences between BrS patients and controls. Therefore, we conducted a systematic review and meta-analysis to investigate the different restitution indices used in BrS. METHODS: PubMed and Embase were searched until April 7, 2019, identifying 20 and 27 studies. RESULTS: A total of ten studies involving 178 BrS (mean age 38 years old, 63% male) and 102 controls (mean age 31 years old, 42% male) were included in this systematic review. Pacing was carried out at the right ventricular outflow tract (RVOT)/right ventricular apex (RPA) (n = 4), RPA (n = 4), or right atrium (RA) (n = 1). Basic cycle lengths of 400 (n = 4), 500 (n = 2), 600 (n = 6) and 750 ms (n = 1) were used. Recording methods include electrograms (n = 4), monophasic action potentials (n = 5), and electrocardiograms (n = 1). Signals were obtained from the RVOT (n = 8), RVA (n = 3), RA (n = 1), or the body surface (n = 1). The maximum restitution slope for endocardial repolarization at the RVOT was 0.87 for BrS patients (n = 5; 95% confidence interval [CI] 0.68-1.07) compared with 0.74 in control subjects (n = 4; 95% CI 0.42-1.06), with a significant mean difference of 0.40 (n = 4; 95% CI 0.11-0.69; P = 0.007). CONCLUSIONS: Steeper endocardial repolarization restitution slopes are found in BrS patients compared with controls at baseline. Restitution analysis can provide important information for risk stratification in BrS.
BACKGROUND:Brugada syndrome (BrS) is an ion channelopathy that predisposes affected subjects to ventricular tachycardia/fibrillation (VT/VF) and sudden cardiac death. Restitution analysis has been examined in BrSpatients but not all studies have reported significant differences between BrSpatients and controls. Therefore, we conducted a systematic review and meta-analysis to investigate the different restitution indices used in BrS. METHODS: PubMed and Embase were searched until April 7, 2019, identifying 20 and 27 studies. RESULTS: A total of ten studies involving 178 BrS (mean age 38 years old, 63% male) and 102 controls (mean age 31 years old, 42% male) were included in this systematic review. Pacing was carried out at the right ventricular outflow tract (RVOT)/right ventricular apex (RPA) (n = 4), RPA (n = 4), or right atrium (RA) (n = 1). Basic cycle lengths of 400 (n = 4), 500 (n = 2), 600 (n = 6) and 750 ms (n = 1) were used. Recording methods include electrograms (n = 4), monophasic action potentials (n = 5), and electrocardiograms (n = 1). Signals were obtained from the RVOT (n = 8), RVA (n = 3), RA (n = 1), or the body surface (n = 1). The maximum restitution slope for endocardial repolarization at the RVOT was 0.87 for BrSpatients (n = 5; 95% confidence interval [CI] 0.68-1.07) compared with 0.74 in control subjects (n = 4; 95% CI 0.42-1.06), with a significant mean difference of 0.40 (n = 4; 95% CI 0.11-0.69; P = 0.007). CONCLUSIONS: Steeper endocardial repolarization restitution slopes are found in BrSpatients compared with controls at baseline. Restitution analysis can provide important information for risk stratification in BrS.
Authors: Ian N Sabir; Lucia M Li; Victoria J Jones; Catharine A Goddard; Andrew A Grace; Christopher L-H Huang Journal: Pflugers Arch Date: 2007-09-06 Impact factor: 3.657
Authors: Kevin M W Leong; Fu Siong Ng; Caroline Roney; Christopher Cantwell; Matthew J Shun-Shin; Nicholas W F Linton; Zachary I Whinnett; David C Lefroy; D Wyn Davies; Sian E Harding; Phang Boon Lim; Darrel Francis; Nicholas S Peters; Amanda M Varnava; Prapa Kanagaratnam Journal: J Cardiovasc Electrophysiol Date: 2017-12-07