Pulmonary function following aortic valve replacement: a comparison between ministernotomy and median sternotomy.

BACKGROUND AND AIM OF THE STUDY Minimally invasive aortic valve replacement (AVR) has several theoretical advantages over standard median sternotomy, but the effects of these techniques on postoperative pulmonary function have not been determined. METHODS Twenty-six patients undergoing AVR through either a ministernotomy (group M; n = 12) or a median sternotomy (group S; n = 14) underwent pulmonary function tests. Forced vital capacity (FVC), forced expiratory volume in one second (FEV1), PaO2 and PaCO2 were determined preoperatively and before hospital discharge (at a mean of five days). Data regarding time to extubation, degree of pain and opening of the pleura were collected prospectively. Both groups had similar preoperative characteristics. RESULTS There was a significant decrease in FVC, FEVJ, PaO2 and PaCO2 during the postoperative period in all patients, though differences between the groups were not significant. Patients in group M referred less pain than those in group S. In this group, the fall in FVC and FEV1 correlated with the degree of pain, while preoperative FVC correlated with early extubation. Pleurotomy did not affect pulmonary function or pain. CONCLUSION FVC, FEV1, PaO2 and PaCO2 are reduced significantly following AVR, but a minimally invasive approach does not prevent postoperative pulmonary dysfunction.