RELATIONSHIP BETWEEN PLEURAL EFFUSION AND PERICARDIAL INVOLVEMENT AFTER MYOCARDIAL REVASCULARIZATION

The explanation for the high incidence of pleural effusion after cardi ac surgery is unclear. There is a high incidence of left pleural effus ion with inflammatory pericardial disease. We hypothesized that after coronary artery bypass grafting (CABG) there would be a higher inciden ce of pleural effusions in patients with pericardial involvement. We p rospectively studied 47 patients undergoing elective CABG; 17 had only saphenous vein grafts (SVG group) and 30 received at least one intern al mammary artery graft (IMA group) in addition to SVG. Patients had a chest radiograph, chest ultrasound, and an echocardiogram on the 7th, 14th, and 30th postoperative days. Seven days after the surgery, 42 t o 47 patients (89.4 percent) had a pleural effusion and 36 (76.6 76.6 percent) pericardial involvement. No relationship was found between th e presence of a pleural effusion and a pericardial effusion (p>0.05). On the 14th postoperative day, 36 patients (76.6 percent) had a pleura l effusion while 33 patients (70.2 percent) had a pericardial effusion . There was a significant relationship between the presence of a pleur al effusion and a pericardial effusion (p<0.05). On the 30th postopera tive day, 27 patients (57.4 percent) had a pleural effusion and 25 (53 .2 percent) had a pericardial effusion. Again, there was a significant relationship between a pleural effusion and a pericardial effusion (p <0.05). Finally, there was no relationship between the ejection fracti on and the presence of pleural effusion at any time (p>0.05). From thi s study, we conclude that there is a high prevalence of both pleural a nd pericardial effusion postoperatively in patients undergoing CABG. B oth types of effusions tend to be asymptomatic, gradually disappear, a nd are more common in the IMA group. Patients who have a persistent pe ricardial effusion are more likely to have a persistent pleural effusi on.