High incidence of ventricular arrhythmias in patients with left ventricular enlargement and moderate left ventricular dysfunction.
BACKGROUND
Left ventricular ejection fraction (LVEF) ≤35% is the cutoff value used to identify patients at high risk of sudden cardiac death. However, whether patients who have moderate left ventricular dysfunction and left ventricular enlargement (LVE) have a high risk of ventricular arrhythmias (VAs) and cardiac death is unclear.


OBJECTIVE
Patients with moderate left ventricular dysfunction and LVE may have a high risk of VAs.


METHODS
This study retrospectively analyzed the data of 853 patients who have an implantable cardioverter-defibrillator/cardiac resynchronization therapy cardioverter-defibrillator equipped with home monitoring. The patients were divided into 4 groups: group A, 35% < LVEF ≤ 45% and left ventricular end-diastolic dimension (LVEDD) ≥60 mm; group B, LVEF ≤35% and LVEDD <60 mm; group C, 35% < LVEF ≤ 45% and LVEDD <60 mm; and group D, LVEF ≤35% and LVEDD ≥60 mm.


RESULTS
During a mean follow-up period of 30 ± 13 months, 324 patients (38%) experienced VAs and 125 patients (14.7%) experienced cardiac death. Based on multivariate Cox regression modeling, group A had an increased risk of VAs (A vs B, hazard ratio [HR]: 1.563, 95% confidence interval [CI]: 1.029-2.375, P = 0.036; A vs C, HR: 1.661, 95% CI: 1.204-2.294, P = 0.002) and cardiac death (A vs B, HR: 1.845, 95% CI: 1.013-3.356; A vs C, HR: 2.041, 95% CI: 1.136-3.731, P = 0.021).


CONCLUSIONS
Patients with moderate left ventricular dysfunction and LVE have a high risk of VAs and cardiac death.
Arrhythmia Center, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Shuang
S
Zhao
Arrhythmia Center, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Keping
K
Chen
Department of Cardiology, Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China.
Yangang
Y
Su
Arrhythmia Center, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Wei
W
Hua
Department of Cardiology, Beijing Hospital, Beijing, China.
Jiefu
J
Yang
Department of Cardiology, Guangdong Cardiovascular Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.
Silin
S
Chen
Department of Cardiology, First Affiliated Hospital of Harbin Medical University, Harbin, China.
Zhaoguang
Z
Liang
Department of Cardiology, Nanjing Drum Tower Hospital, Nanjing, PR China.
Wei
W
Xu
Arrhythmia Center, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Shu
S
Zhang
D058406:Cardiac Resynchronization Therapy / Q000379:methods; D002681:China / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D013318:Stroke Volume / Q000502:physiology*; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy; D013997:Time Factors; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D016277:Ventricular Function, Left / Q000502:physiology*
implantable cardioverter defibrillator; left ventricular ejection fraction; left ventricular end-diastolic dimension; ventricular arrhythmias