Gender Differences in Perioperative Atrial Fibrillation and 5-Year Outcome after Off-Pump Coronary Artery Bypass Grafting

Background: Postoperative atrial fibrillation (POAF) is a common complication after cardiac surgery. Recent studies presented a strong association of POAF to stroke. Since men and women differ regarding several comorbidities, pathophysiology, and progression of cardiac diseases, this study sought to assess sex-related differences regarding the occurrence of POAF.

Methods: All consecutive patients who underwent elective off-pump coronary artery bypass grafting between 2014 and 2016 were retrospectively included. Cohorts were divided by their sex, while propensity score (PS) matching by all available baseline characteristics was performed to reach group comparability. The primary endpoint was defined as the occurrence of perioperative atrial fibrillation. Secondary endpoints were a 5-year outcome of a composite endpoint of all-cause mortality and stroke. The association of the CHA2DS2-VASc Score to the occurrence of POAF was assessed by ordinal regression by polytomous universal model.

Results: A total of 1,193 patients were included with 998 male and 195 female patients. Propensity score matching resulted in a cohort of 390 patients with 195 in each group. POAF occurrence did not show a significant difference between the groups with 32.3 and 26.2% (OR 0.7, 95%CI [0.48; 1.2], p = 0.18) in male and female patients, respectively. The 5-year follow-up of the composite endpoint of all-cause mortality and stroke revealed a general worse outcome in male patients, with a similar increase of the likelihood toward the composite endpoint in the total cohort and in both sexes (total cohort: 12.3% versus 20.2%, HR 1.7 95%CI [0.99; 2.86], p = 0.05; male: 15.2% versus 25.4%, HR 1.7 95%CI [0.9; 3.36], p = 0.10; female: 9.7% versus 13.7%, HR 1.4 95%CI [0.58; 3.53], p = 0.44). Changes in the composite endpoint were mainly driven by a higher rate of all-cause mortality in the total cohort (8.7% versus 16.7%, HR 2.0 95%CI [1.09; 3.63], p = 0.025) and in both groups (male: 12.1% versus 20.6%, p = 0.13; female: 5.6% versus 11.8%, p = 0.14). The ordinal regression model showed an association of an increasing CHA2DS2-VASc Score to the development of POAF in the total cohort and both sexes.

Conclusion: There was no difference in the occurrence of postoperative atrial fibrillation between male and female patients. POAF occurrence resulted in a tendency toward a worse outcome regarding a composite endpoint of all-cause mortality and stroke. An increasing CHA2DS2-VASc Score was associated with an increasing occurrence of postoperative atrial fibrillation in both sexes.

Publication History

Article published online:
11 February 2025