New-onset sustained ventricular tachycardia and fibrillation early after cardiac operations.
BACKGROUND
Malignant ventricular tachyarrhythmia early after cardiac surgery is an uncommon arrhythmic complication but has a negative impact on mortality. The purpose of this study was to evaluate the incidence of new-onset sustained postoperative ventricular tachycardia-ventricular fibrillation and to identify risk factors for the dysrhythmia.


METHODS
Demographic, clinical, operative, and postoperative data, including a variable of postoperative ventricular tachycardia, were prospectively obtained from 4748 patients undergoing nonemergency coronary artery bypass graft and(or) valve replacement with no history of sustained ventricular tachycardia or sudden death. A detailed analysis was performed to define the risk factors for the ventricular tachycardia and the prognostic impact of the arrhythmia on 30-day mortality was evaluated.


RESULTS
Forty-five patients (0.95%) had sustained ventricular tachycardia or ventricular fibrillation and the initial episode occurred 3.9 +/- 5.2 days (mean +/- standard deviation) after surgery. By multivariate analysis, female sex (odds ratio, 1.982), left ventricular ejection fraction (< 35%: > 50%, 4.771), the presence of pulmonary hypertension (3.066), the presence of systemic hypertension (2.391), and pump time (per 10 minutes, 1.085) were independently associated with the dysrhythmias. Early mortality of patients with the arrhythmia was 28.9%, strikingly higher than that of patients without ventricular tachycardia/ventricular fibrillation (1.9%).


CONCLUSIONS
Left ventricular ejection fraction is the strongest risk factor for new-onset postoperative sustained ventricular tachycardia-ventricular fibrillation; female sex, pump time, pulmonary and systemic hypertension are independent predictors of the dysrhythmias; the arrhythmia is associated with increased 30-day mortality after cardiac surgery.
Yeung-Lai-Wah
John A
JA
Division of Cardiology and Cardiovascular Surgery, St Paul's Hospital, University of British Columbia, Vancouver, British Columbia, Canada.
Qi
Anzhen
A
McNeill
Elizabeth
E
Abel
James G
JG
Tung
Stanley
S
Humphries
Karin H
KH
Kerr
Charles R
CR
D000368:Aged; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D001026:Coronary Artery Bypass / Q000009:adverse effects; D005260:Female; D006351:Heart Valves / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D011446:Prospective Studies; D012307:Risk Factors; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy; D014693:Ventricular Fibrillation / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy