Persistent symptomatic pleural effusion following coronary bypass surgery: clinical and histologic features, and treatment

Pleural effusions following coronary artery bypass grafting (CABG) have been reported in 65%-89% of the cases. The majority of pleural effusions are left-sided, of little significance, and resolve spontaneously. However, a few pleural effusions require specific therapeutics. We report clinical and pleural histologic features of three patients who had persistent post-CABG pleural effusions and underwent video-assisted thoracic surgery (VATS). These patients were studied because they had a persistent pleural effusion within the first 2 months after CABG without other identifiable causes. All patients underwent VATS for investigation and management of persistent pleural effusions. Three patients with a mean age of 63.6 +/- 8.5 years were studied. The pleural effusion developed 38 +/- 11.3 days after CABG (range: 22-46). The median period from CABG to VATS was 80 +/- 21.6 days (range: 50-100). In all cases, the pleural effusion was large, and predominated on the left side. Pleural effusions were characterized by an exudative (n = 2) or transudative (n = 1) fluid with lymphocytosis. Histologic examination of pleural biopsies showed a follicular lymphoid hyperplasia involving the pleural serosa and a non-necrotizing granulomatous reaction with a mild inflammatory infiltrate. All patients underwent VATS with intrapleural injection of sclerosing agents. Video-assisted thoracic surgery talc pleurodesis led to symptomatic and radiologic improvement in all patients with a mean follow-up of 16.7 +/- 4.5 months. No recurrence of pleural effusion has been observed in any patient. Large pleural effusions can develop in a small proportion of patients after CABG. The mechanism of pleural effusion remains unclear. Video-assisted thoracic surgery could play a significant role in the management of pleural effusion developing after CABG.