Pulmonary function and immediate outcome of patients undergoing aortic valve replacement

The study aim was to evaluate whether pulmonary function, as assessed by spirometry, affects immediate outcome after aortic valve replacement (AVR).

Data relating to the preoperative percentages of predicted forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) were retrieved from a series of 453 patients who underwent AVR, with or without coronary artery bypass surgery.

The percentage of predictive FVC (odds ratio (OR) 0.952; 95% CI 0.914-0.990; AUC 0.749; p = 0.019), but not of predicted FEV1, nor any history of pulmonary disease, proved to be independent predictors of in-hospital mortality, even when adjusted for the logistic EuroSCORE. A percentage predictive FVC of < 80% proved to be the best cut-off (in-hospital mortality 6.3% versus 1.3%; p = 0.005; OR 5.100; 95% CI 1.544-16.849; specificity 69%, sensitivity 69%). The percentage of predictive FVC was found to be an independent predictor of stroke (OR 0.956; 95% CI 0.923-0.989; p = 0.009). Patients with a percentage of predictive FVC < 80% had a risk of postoperative stroke of 6.9% versus 1.9% among those patients with better FVC values (OR 3.769; 95% CI 1.342-10.581; p = 0.012). Patients with a percentage of predictive FVC < 80% (10.4% versus 4.2%; OR 2.648; 95% CI 1.225-5.724; p = 0.011) and a history of pulmonary disease (13.1% versus 5.1%; OR 2.808; 95% CI 1.117-6.694; p = 0.016) had a significantly higher risk of an intensive care unit stay of five or more days. Postoperative pneumonia was not associated with either spirometric parameters, nor with any history of pulmonary disease.

Pulmonary disease, as indicated by decreased preoperative values of FVC and FEV1, is an important comorbidity factor in patients undergoing AVR surgery. Further studies are required to demonstrate whether the identification and treatment of these patients could improve their outcome after AVR.