Takashi Noda1, Takashi Kurita2, Takashi Nitta3, Yasutaka Chiba4, Hiroshi Furushima5, Naoki Matsumoto6, Takeshi Toyoshima7, Akihiko Shimizu8, Hideo Mitamura9, Ken Okumura10, Tohru Ohe11, Yoshifusa Aizawa12. 1. Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, Suita, Japan. 2. Department of Internal Medicine, Faculty of Medicine, Kindai University, Osaka-Sayama, Japan. Electronic address: kuritat@med.kindai.ac.jp. 3. Department of Cardiovascular Surgery, Nippon Medical School, Tokyo, Japan. 4. Clinical Research Center, Kindai University Hospital, Osaka-Sayama, Japan. 5. The First Department of Internal Medicine, Niigata University School of Medicine, Niigata, Japan. 6. Department of Pharmacology, St. Marianna University School of Medicine, Kawasaki, Japan. 7. Faculty of Health and Medical Care, Saitama Medical University, Saitama, Japan. 8. Faculty of Health Sciences, Yamaguchi University Graduate School of Medicine, Ube, Japan. 9. Cardiovascular Center, Tachikawa Hospital, Tachikawa, Japan. 10. Department of Cardiology, Saiseikai Kumamoto Hospital, Kumamoto, Japan. 11. Okayama City Hospital, Okayama, Japan. 12. Department of Research and Development, Tachikawa Medical Center, Niigata, Japan.
Abstract
BACKGROUND: Electrical storm (E-Storm), defined as multiple episodes of ventricular arrhythmias within a short period of time, is an important clinical problem in patients with an implantable cardiac defibrillator (ICD) including cardiac resynchronization therapy devices capable of defibrillation. The detailed clinical aspects of E-Storm in large populations especially for non-ischemic dilated cardiomyopathy (DCM), however, remain unclear. OBJECTIVE: This study was performed to elucidate the detailed clinical aspects of E-Storm, such as its predictors and prevalence among patients with structural heart disease including DCM. METHODS: We analyzed the data of the Nippon Storm Study, which was a prospective observational study involving 1570 patients enrolled from 48 ICD centers. For the purpose of this study, we evaluated 1274 patients with structural heart disease, including 482 (38%) patients with ischemic heart disease (IHD) and 342 (27%) patients with DCM. RESULTS: During a median follow-up of 28months (interquartile range: 23 to 33months), E-Storm occurred in 84 (6.6%) patients. The incidence of E-Storm was not significantly different between patients with IHD and patients with DCM (log-rank p=0.52). Proportional hazard regression analyses showed that ICD implantation for secondary prevention of sudden cardiac death (p=0.0001) and QRS width (p=0.015) were the independent risk factors for E-storm. In a comparison between patients with and without E-Storm, survival curves after adjustment for clinical characteristics showed a significant difference in mortality. CONCLUSION: E-Storm was associated with subsequent mortality in patients with structural heart disease including DCM.
BACKGROUND: Electrical storm (E-Storm), defined as multiple episodes of ventricular arrhythmias within a short period of time, is an important clinical problem in patients with an implantable cardiac defibrillator (ICD) including cardiac resynchronization therapy devices capable of defibrillation. The detailed clinical aspects of E-Storm in large populations especially for non-ischemic dilated cardiomyopathy (DCM), however, remain unclear. OBJECTIVE: This study was performed to elucidate the detailed clinical aspects of E-Storm, such as its predictors and prevalence among patients with structural heart disease including DCM. METHODS: We analyzed the data of the Nippon Storm Study, which was a prospective observational study involving 1570 patients enrolled from 48 ICD centers. For the purpose of this study, we evaluated 1274 patients with structural heart disease, including 482 (38%) patients with ischemic heart disease (IHD) and 342 (27%) patients with DCM. RESULTS: During a median follow-up of 28months (interquartile range: 23 to 33months), E-Storm occurred in 84 (6.6%) patients. The incidence of E-Storm was not significantly different between patients with IHD and patients with DCM (log-rank p=0.52). Proportional hazard regression analyses showed that ICD implantation for secondary prevention of sudden cardiac death (p=0.0001) and QRS width (p=0.015) were the independent risk factors for E-storm. In a comparison between patients with and without E-Storm, survival curves after adjustment for clinical characteristics showed a significant difference in mortality. CONCLUSION: E-Storm was associated with subsequent mortality in patients with structural heart disease including DCM.