Clinical significance of pleural effusion in acute aortic dissection

STUDY OBJECTIVE: To clarify the clinical significance of pleural effusion in the clinical course of acute aortic dissection (AAD). DESIGN: Retrospective clinical series. SETTING: A university hospital. PATIENTS: Fifty-five patients strongly suspected of having AAD because of severe chest or back pain. Patients with obvious ischemic heart disease, lung disease, and pleural disease were excluded. INTERVENTIONS: An additional diagnosis of pleural effusion was made when evident by CT. MEASUREMENTS AND RESULTS: Pleural effusion was detected in 42 of 48 patients (88%) with AAD (mean plus minus SD age, 65 plus minus 12 years; 35 men and 13 women), but in only 1 of 7 patients (14%) who proved not to have AAD (mean age, 74 +/- 10 years; 6 men and 1 woman). Effusion appeared at a mean of 4.5 days after onset of dissection. Thoracentesis performed in six patients showed a bloody effusion in three patients and an exudative effusion in three patients. In the six AAD patients without pleural effusion, four patients underwent surgery within 3 days after onset of dissection. In patients with AAD, effusion was demonstrated on the first CT after hospital admission in 18 patients, and was bilateral in 32 patients. WBC count in blood, serum C-reactive protein concentration, and body temperature were higher in patients with effusion (13,400 +/- 3,600/microL, 18.4 +/- 11.5 mg/dL, and 38.2 +/- 0.7 degrees C) than in those without effusion (10,300 +/- 2,900/microL, 4.5 +/- 4.2 mg/dL, and 37.0 +/- 1.0 degrees C, respectively). CONCLUSIONS: Pleural effusion occurs frequently in patients with AAD, often in association with inflammatory reactions.