Background and aim of the study: Congestive heart failure (CHF) after aortic valve replacement (AVR) is an important cause of morbidity. The study aim was to identify preoperative risk factors for CHF.
Methods: A total of 500 consecutive patients (271 males, 229 females; median age 73 years; range: 71-77 years) was investigated retrospectively. The AVR was performed using a Carpentier-Edwards pericardial valve, and a total of 348 additional procedures (313 coronary artery bypass grafts; CABG) was carried out. The outcome studied was CHF, during both hospital stay and long-term follow up. Univariate and multivariate statistical analyses were used to investigate 15 risk factors.
Results: During the hospital stay, 13 patients developed CHF, with four fatalities. Significant risk factors for CHF included urgent operation (p = 0.031), preoperative atrial fibrillation (AF) (p = 0.031) and NYHA functional class IV (p = 0.05). A logistic regression analysis revealed need for urgent operation (p = 0.034) as the sole factor. During long-term follow up, 43 patients developed CHF, with seven fatalities. Univariate analysis identified seven risk factors with significant effect: valve size <19 mm (p = 0.004), preoperative conduction defects (p = 0.007), chronic postoperative AF (p = 0.013), cross-clamp time >75 min (p = 0.032), NYHA class IV (p = 0.041), coronary artery disease (CAD) (p = 0.043) and additional CABG (p = 0.050). Multivariate analysis identified three risk factors: preoperative conduction defects (p = 0.004), postoperative AF (p = 0.005) and CAD (p = 0.037)
Conclusion: Morbidity due to CHF after AVR could be minimized with correct treatment of AF and of conduction defects. Patient age, valve size, cross-clamp time and preoperative severity or symptoms were not independent risk factors. Moreover, small native aortic valve rings should not necessarily be enlarged, the cross-clamp time should be kept to a minimum, and surgery should not be delayed when symptoms have developed.