Predictors of new malignant ventricular arrhythmias after coronary surgery: a case-control study.
OBJECTIVE
We sought to investigate the relationship between perioperative factors and the occurrence of ventricular tachycardia (VT) and ventricular fibrillation (VF), as well as the impact of VT/VF on early and late mortality.


BACKGROUND
Both VT and VF are rare but serious complications after coronary artery bypass graft surgery (CABG), and their etiology and implications remain uncertain.


METHODS
Data on 4,411 consecutive patients undergoing CABG (1,154 [25.8%] had off-pump surgery) between April 1996 and September 2001 were extracted from a prospective database and analyzed. Odds ratios (ORs) describing associations between possible risk factors and VT/VF were estimated separately. Factors observed to be significantly associated with VT/VF were further investigated using multivariate logistic regression.


RESULTS
Sixty-nine patients suffered VT/VF (1.6%). There were 61 (1.4%) in-hospital/30-day deaths, 15 among patients who had postoperative VT/VF (21.7%). Patient factors independently associated with an increase in the odds of VT/VF included age <65 years, female gender, body mass index <25 kg/m(2), unstable angina, moderate or poor ejection fraction, and the need for inotropes and an intra-aortic balloon pump (OR 1.72 to 4.47, p < 0.05). After adjustment, off-pump surgery was associated with a substantial but nonsignificant protective effect against VT/VF (OR 0.53, 95% confidence interval [CI] 0.25 to 1.13; p = 0.10). Actuarial survival at two years was 98.2% among patients who had VT/VF and who survived to discharge/30 days, compared with 97.0% for the control group (adjusted hazard ratio 0.96 (95% CI 0.40 to 2.31, p = 0.92).


CONCLUSIONS
The incidence of VT/VF is low in patients undergoing coronary surgery but is associated with high in-hospital mortality. The late survival of the discharged VT/VF patients compares favorably with that of controls.
Ascione
Raimondo
R
Bristol Heart Institute, Bristol Royal Infirmary, Bristol, United Kingdom. R.Ascione@bristol.ac.uk
Reeves
Barnaby C
BC
Santo
Kirkpatrick
K
Khan
Nouman
N
Angelini
Gianni D
GD
D000293:Adolescent; D000328:Adult; D000368:Aged; D015992:Body Mass Index; D016022:Case-Control Studies; D001026:Coronary Artery Bypass; D003327:Coronary Disease / Q000453:epidemiology / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012307:Risk Factors; D013223:Statistics as Topic; D016019:Survival Analysis; D017180:Tachycardia, Ventricular / Q000453:epidemiology / Q000209:etiology*; D016896:Treatment Outcome; D006113:United Kingdom / Q000453:epidemiology; D014693:Ventricular Fibrillation / Q000453:epidemiology / Q000209:etiology*