Pre-operative atrial fibrillation is independently associated with short and long-term mortality after aortic valve replacement

Abstract

Background: Atrial fibrillation (AF) is the commonest cardiac arrhythmia, becoming increasing prevalent as the population ages, and is an important risk factor for stroke. There are conflicting results around whether AF is associated with adverse outcomes after aortic valve replacement (AVR) amongst the few studies that have investigated this. We compared the characteristics and outcomes of patients undergoing AVR by history of AF. Methods: Isolated AVR patients at Auckland City Hospital 2005-2012 were divided into those with and without pre-operative AF for comparative analyses. Results: Amongst 620 patients, 19.2% (119) had permanent or paroxysmal AF pre-operatively. Patients with AF were significantly older (70.5 vs 63.4 years, p < 0.001), had higher proportion of New Zealand European (82.4% vs 68.1%, p = 0.004), urgent or emergency operation (62.1% vs 48.3%, p = 0.016), NYHA class III-IV (55.4% vs 37.4%,p = 0.004), history of stroke (10.9% vs 5.0%, p = 0.031), pulmonary hypertension (27.8% vs 16.2%, p = 0.002), 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 AF. After adjusting for significant variables, pre-operative AF remained an independent predictor of operative mortality odds ratio 3.38 (95% confidence interval 1.18-9.69), mortality during follow-up 2.36 (1.44-3.87) and prolonged ventilation>24 hours 2.48 (1.32-4.69). Conclusions: AF was associated with a number of 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 AF ablation be considered when AVR is performed. CSANZ NZ AbstractsHeart, Lung and CirculationVol. 23Preview Full-Text PDF