Preoperative atrial fibrillation predicts mortality and morbidity after aortic valve replacement

Atrial fibrillation (AF) is the commonest cardiac arrhythmia, becoming increasingly prevalent as the population ages. There is conflicting information around whether AF is associated with adverse outcomes after aortic valve replacement (AVR) from the few studies that have investigated this. We compared the characteristics and outcomes of patients undergoing AVR with their history of AF.

Isolated AVR patients at Auckland City Hospital 2005-2012 were divided into those with and without preoperative AF for comparative analyses.

Of 620 consecutive patients, 19.2% (119) had permanent or paroxysmal AF preoperatively. Patients with AF were significantly older (70.5 vs 63.4 years, P < 0.001) and were more likely to be New Zealand European (82.4 vs 68.1%, P = 0.004). They also had higher prevalence of NYHA class III-IV (55.4 vs 37.4%, P = 0.004), inpatient operation (62.1 vs 48.3%, P = 0.008), history of stroke (10.9 vs 5.0%, P = 0.031), lower creatinine clearance (73 vs 82, P = 0.001) and higher EuroSCORE II (5.2 vs 3.4%, P < 0.001). Operative mortality (6.7 vs 2.0%, P = 0.012) and composite morbidity (27.7 vs 16.5%, P = 0.006) were also higher in patients with AF. After adjusting for significant variables, preoperative AF remained an independent predictor of operative mortality with an odds ratio of 3.44 (95% confidence interval 1.29-9.13), composite morbidity of 1.79 (1.05-3.04) and a mortality during follow-up hazards ratio of 2.36 (1.44-3.87).

AF was associated with several cardiovascular and cardiac surgery risk factors, but remained independently associated with short- and long-term mortality. AF should be incorporated into cardiac surgery risk models and surgical AF ablation may be considered with AVR.