What factors predict postoperative pulmonary and pleural complications following aortic valve replacement? Retrospective study. One thousand consecutive patients who underwent aortic valve replacement with a pericardial valve between 1986 and 2006. Of these, 610 underwent also coronary artery surgery. Thirty putative predictors were investigated. Postoperative pulmonary complications (defined as respiratory failure, pneumonia, atelectasis) and postoperative pleural complications (defined as pleural effusion, pneumothorax, haemothorax, empyema) within 30 days of surgery were identified. 58 (6%) patients developed pulmonary complications and 45 (5%) developed pleural complications. None of the pleural and only 3 of the pulmonary complications were fatal if they occurred alone. Postoperative heart failure (OR 4.7, 95% CI 1.8 to 11.9), previous pacemaker implant (OR 4.4, 95% CI 1.8 to 11.2) and chronic obstructive pulmonary disease (OR 1.7, 95% CI 1.0 to 3.1) independently predicted postoperative pulmonary complications. Postoperative bleeding (OR 7.4, 95% CI 1.8 to 29.9), carotid artery disease (OR 2.8, 95% CI 1.4 to 5.5), previous coronary artery surgery (OR 2.7, 95% CI 1.1 to 6.4), chronic obstructive pulmonary disease (OR 1.9, 95% CI 1.0 to 3.8) and cardiac conduction defect (OR 1.9, 95% CI 1.0 to 3.7) independently predicted postoperative pleural complications. Postoperative pulmonary and pleural complications were rare. A history of cardiac and/or pulmonary problems are risk factors for pulmonary complications after aortic valve replacement. Further study is needed to reveal if preventive physiotherapeutic intervention in these patients is effective.