PULMONARY COMPLICATIONS FOLLOWING MYOCARDIAL REVASCULARIZATION WITH THE INTERNAL MAMMARY ARTERY GRAFT

A total of 106 patients participated in a clinical investigation todetermine the incidence and etiology of pulmonary complications followingmyocardial revascularization with the internal mammary artery graft; 39patients (group I), undergoing valve replacement or myocardialrevascularization with vein grafts, served as control. The mammary arterywas used for revascularization in the remaining patients. The pleura wasopened during the dissection of the mammary graft in 34 patients (groupII), but was left intact during harvesting of the internal mammary arteryin 33 patients (group III). Inspiration and expiration chest X-rays wereobtained during the first 3 months of convalescence to determine thepresence of pleural fluid, the position of the left hemidiaphragm, and toasses diaphragmatic movement. Pleural effusions, left lower-lobeatelectasis, and elevation of the left hemidiaphragm were observed in allgroups after operation, but were more commonly observed in those patientsundergoing revascularization with the mammary artery graft. Postoperativechest X-rays just prior to discharge from hospital were normal in 69% ofthe control group, only 9% of patients in group II who had pleurotomyduring mammary artery dissection, and 42% of group III. By 3 months, however, 95% of patients in groups I and II had normal chest X-rays, whereas 53% of patients in group II had persistent loss of left-lung volumerelated to the presence of left-lower-lobe atelectasis, left pleuraleffusions and organization of the postoperative hemothorax.Our data indicate that the pleura should not be opened during dissection of the internal mammary artery graft because pleurotomy is associated with a high incidence of postoperative pulmonary complications that contribute to chronic loss of left lung volume. [Eur J Cardio-thorac Surg (1990) 4: 156-162]. © Springer-Verlag.