Outcomes of Acute Type A Aortic Dissection After Previous Cardiac Surgery

Background. Reports on outcomes of acute type A aortic dissection (ATAAD) repair after previous cardiac surgery (PCS) are few. Some suggest no difference in mortality while others note decreased risk of free rupture due to adhesions. We analyzed our experience of ATAAD after PCS. Methods. Between January 1992 and March 2009 we repaired 330 patients with ATAAD. Of these, 49 (15%) patients had PCS: coronary artery bypass in 30 (61%), aortic valve replacement in 8 (16%), coronary artery bypass/aortic valve replacement in 5 (10%), aortic valve replacement-mitral repair in 1 (2%), aortic valve replacement- tricuspid repair in 1 (2%), and others in 4 (9%) patients. The ATAAD patients with and without PCS (primary) were compared. Results. The PCS group was older (63 vs 58 years, p < 0.02), more frequently men (82% vs 67%, p < 0.04), and less likely to have aortic insufficiency (30% vs 47%, p < 0.05). Otherwise, the PCS group did not differ in clinical presentation, with similar malperfusion and tamponade. Operative procedures did not differ between groups except for repair of pulmonary artery fistula (4% vs 0%, p < 0.03), more use of Cabrol shunt (18% vs 3%), p < 0.03), and more frequent need for mechanical cardiac support in the PCS group (8% vs 3.6%, p < 0.04). The PCS group suffered more strokes (10% vs 2.5%, p < 0.03), temporary neurologic deficits (24% vs 10%, p < 0.007), and higher hospital mortality (31% vs 13.8%, p < 0.007) than the no-PCS group. Conclusions. Patients with ATAAD after PCS exhibited similar risks for malperfusion, hypotension, and cardiac tamponade. This suggests that adhesions formed after PCS do not eliminate the risk of cardiac tamponade from aortic rupture. Although results from surgical repair are acceptable, justifying timely repair, mortality still remains higher than without prior history of cardiac surgery. (Ann Thorac Surg 2010;89:1467-74) (C) 2010 by The Society of Thoracic Surgeons