REOPERATIONS AFTER OPERATION ON THE THORACIC AORTA - ETIOLOGY, SURGICAL TECHNIQUES, AND PREVENTION

Recurrent aortic aneurysms, persistent or new dissection, new onset of valvular and coronary artery disease, graft infection, and prosthetic endocarditis are not rare after thoracic aortic operations; they can be difficult to diagnose and represent a formidable surgical challenge . Between 1977 and 1991, 876 operations were performed on the thoracic aorta in our institution: 340 in dissections, 299 in true aneurysms, 150 for aortic remodeling and external wall support during aortic valv e replacement, and 87 for miscellaneous causes. During the same period , there were 193 additional reoperations. Vascular reoperations on abd ominal aorta and peripheral arteries accounted for 73 cases and are no t further discussed in this study. The reasons for reoperation (n = 13 0) in 120 patients were: failure of biologic valves (n = 23); aneurysm recurrence in a proximal or distal aortic segment (n = 21); pseudoane urysm formation at suture lines (n = 13); new dissection or dilatation involving ascending aorta (n = 11), aortic arch (n = 13), and descend ing aorta (n = 10); aneurysm after aortic remodeling (n = 13); new ons et of valvular disease (n = 5); and new onset of coronary disease (n = 5). Infected aortic graft and prosthetic endocarditis accounted for 1 0 reoperations, and a planned two-staged procedure was performed in 6 patients. Omitting the failed biologic valves, reoperations were perfo rmed on the aortic segment previously operated on in 69.3% of the case s and on other thoracic segments in 30.7%. Overall hospital mortality rate after reoperation was 5.8%. A significant decrease in operative m ortality was observed in the most recent period (3.0% between 1989 and 1991). Reoperations are technically demanding, and some of them are p reventable; therefore (1) graft inclusion technique should be abandone d in ascending aortic operation due to formation of false aneurysms; ( 2) in patients with Marfan syndrome, complete repair of the diseased a orta should be attempted during the initial operation; (3) aortic arch dissection should be repaired definitively during the first operation in low-risk patients; (4) biological valves should be avoided in aneu rysm operations; and (5) homograft replacement is the treatment of cho ice in prosthetic endocarditis or in infected composite graft after an aortic valve or ascending aortic operation.