Compared with matched controls, patients with postoperative atrial fibrillation (POAF) have increased long-term AF after CABG, and POAF is further associated with increased ischemic stroke, heart failure and mortality even after adjustment for AF.

OBJECTIVE: To analyze (1) associations between postoperative atrial fibrillation (POAF) after CABG and long-term cardiovascular outcome, (2) whether associations were influenced by AF during follow-up, and (3) if morbidities associated with POAF contribute to mortality. METHODS: An observational cohort study of 7145 in-hospital survivors after isolated CABG (1996-2012), with preoperative sinus rhythm and without AF history. Incidence of AF was compared with matched controls. Time-updated covariates were used to adjust for POAF-related morbidities during follow-up, including AF. RESULTS: Thirty-one percent of patients developed POAF. Median follow-up was 9.8 years. POAF patients had increased AF compared with matched controls (HR 3.03; 95% CI 2.66-3.49), while AF occurrence in non-POAF patients was similar to controls (1.00; 0.89-1.13). The observed AF increase among POAF patients compared with controls persisted over time (> 10 years 2.73; 2.13-3.51). Conversely, the non-POAF cohort showed no AF increase beyond the first postoperative year. Further, POAF was associated with long-term AF (adjusted HR 3.20; 95% CI 2.73-3.76), ischemic stroke (1.23; 1.06-1.42), heart failure (1.44; 1.27-1.63), overall mortality (1.21; 1.11-1.32), cardiac mortality (1.35; 1.18-1.54), and cerebrovascular mortality (1.54; 1.17-2.02). These associations remained after adjustment for AF during follow-up. Adjustment for other POAF-associated morbidities weakened the association between POAF and overall mortality, which became non-significant. CONCLUSIONS: Patients with POAF after CABG had three times the incidence of long-term AF compared with both non-POAF patients and matched controls. POAF was associated with long-term ischemic stroke, heart failure, and corresponding mortality even after adjustment for AF during follow-up. The increased overall mortality was partly explained by morbidities associated with POAF.

High incidence of atrial fibrillation after coronary surgery.

OBJECTIVES: Postoperative atrial fibrillation (POAF) affects a third of all patients after coronary artery bypass surgery (CABG), but short-term follow-up of heart rhythm after discharge has been sporadic and shown varied results. The aim of this study was to examine the incidence of post-discharge atrial fibrillation (AF) for 30 days following hospital discharge after CABG. METHODS: A total of 67 patients, 19 (28%) with POAF during the initial hospitalization and 48 (72%) without POAF were included. Patients recorded intermittent electrocardiogram registrations three times daily, and additionally in case of arrhythmia symptoms. Presence of post-discharge AF was compared between the groups. All patients were in sinus rhythm at discharge. RESULTS: Twenty of 67 patients (30%) were diagnosed with post-discharge AF. Overall, 35% of them were entirely asymptomatic. POAF patients had a higher incidence of post-discharge AF (11 of 19, 58%) than non-POAF patients (9 of 48, 19%), with six times the odds of developing post-discharge AF compared with non-POAF patients [odds ratio (OR) 6.0; 95% CI 1.9-19, P = 0.002]. Patients with POAF registered episodes of post-discharge AF earlier during the follow-up period (mean Day 3 after discharge, range 1-9 days) than non-POAF patients (Day 10, range 7-14 days, P < 0.001). CONCLUSIONS: A high incidence of both symptomatic and asymptomatic AF was recorded during 30 days following hospital discharge after CABG. The incidence was highest among patients with POAF, of whom more than half experienced post-discharge AF.

The effect of concomitant cardiac resynchronization therapy on quality of life in patients with heart failure undergoing cardiac surgery.

OBJECTIVES: To evaluate the effect of concomitant cardiac resynchronization therapy (CRT) on health related quality of life (QoL) in patients with heart failure (HF) and ventricular dyssynchrony undergoing cardiac surgery. METHODS: Twenty-eight patients received permanent epicardial CRT in connection to coronary artery bypass grafting (CABG) and/or aortic valve replacement (AVR) (CRT group). Thirty-seven HF patients without concomitant CRT served as a comparison group (non-CRT group). SF-36 was used to assess QoL in the two groups and was also compared with the general Swedish population. RESULTS: The median follow-up time was 28 months after surgery (range 8 to 44 months). No difference in QoL could be shown between the CRT group and the comparison group. Several subscales of QoL in the CRT group were in range with the general Swedish population. CONCLUSION: Concomitant CRT for patients with HF and ventricular dyssynchrony undergoing CABG and/or AVR did not result in a higher estimated QoL compared to HF patients without CRT.

Postoperative atrial fibrillation predicts cause-specific late mortality after coronary surgery.

OBJECTIVES: To investigate the association between postoperative atrial fibrillation (POAF) and cause-specific death after coronary artery bypass grafting (CABG) over time. DESIGN: The cohort included 6821 patients undergoing primary isolated CABG between 1996 and 2009. Survival analyses using Cox proportional hazards determined the association between POAF and late mortality and cause of death. Four categories of mortality were examined: cardiac mortality; and death related to arrhythmia, cerebrovascular disease, and heart failure. RESULTS: Median follow-up was 9.8 years and 2152 of 6821 patients (32%) developed POAF. During follow-up, 2302 of 6821 patients (34%) died. For all mortality categories, lower survival rates were found among POAF patients. After adjustment for baseline characteristics, medical history, and preoperative status, POAF was related to increased mortality in all four categories: cardiac mortality (HR 1.4; 95% CI 1.3-1.5); death related to arrhythmia (HR 1.8; 95% CI 1.6-2.0); cerebrovascular disease (HR 1.4; 95% CI 1.2-1.6); and heart failure (HR 1.4; 95% CI 1.3-1.6). The effect remained more than 8 years after surgery. CONCLUSIONS: POAF predicts cause-specific late mortality after CABG, with a sustained effect many years postoperatively. This suggests that POAF-episodes are not merely an indication of more advanced disease at surgery, but predicts a persistent negative effect on cause-specific survival.

Prediction of postoperative atrial fibrillation in a large coronary artery bypass grafting cohort.

The objective of this study was to identify and evaluate predictors of postoperative atrial fibrillation (POAF) in a large coronary artery bypass grafting (CABG) cohort. This was a single centre study of 7115 consecutive patients with preoperative sinus rhythm who underwent isolated CABG between January 1996 and December 2009. Independent risk factors for POAF were identified with multiple logistic regression. The predictive quality of the final model was evaluated by comparing predicted and observed events of POAF, in an effort to find patients at high risk of developing POAF. After CABG, 2270 patients (32%) developed POAF during hospital stay. Independent risk factors of POAF included advancing age (odds ratio, OR 2.0-7.3), preoperative S-creatinine ≥ 150 µmol/l (OR 1.6), male gender (OR 1.2), New York Heart Association class III/IV (OR, 1.2), smoking (OR 1.1), prior myocardial infarction (OR 1.1) and absence of hyperlipidemia (OR 0.9). The final prediction model was moderate (area under curve, 0.62; 95% confidence interval, 0.61-0.64). Patients with POAF had more postoperative complications, including a higher incidence of stroke and increased length of hospital stay. In conclusion, several risk factors for POAF were identified, but the moderate value of the prediction model confirms the difficulty of identifying patients at high risk of developing POAF after CABG.