New paradigms and improved results for the surgical treatment of acute type A dissection

Objective To examine the effect of an integrated surgical approach to the t reatment of acute type A dissections. Summary Background Data Acute type A dissection requires surgery to prevent death from proximal aortic rupture or malperfusion. Most series of the pas t decade have reported a death rate in the range of 15% to 30%. Methods From January 1994 to March 2001, 104 consecutive patients underwent repair of acute type A dissection. All had an integrated operative managem ent as follows: intraoperative transesophageal echocardiography; hypothermi c circulatory arrest (HCA) with retrograde cerebral perfusion (RCP) to repl ace the aortic arch; HCA established after 5 minutes of electroencephalogra phic (EEG) silence in neuromonitored patients (66%) or after 45 minutes of cooling in patients who were not neuromonitored (34%); reinforcement of the residual arch tissue with a Teflon felt "neo-media"; cannulation of the ar ch graft to reestablish cardiopulmonary bypass at the completion of HCA (an tegrade graft perfusion); and remodeling of the sinus of Valsalva segments with Teflon felt "neo-media" and aortic valve resuspension (78%) or replace ment with a biologic or mechanical valved conduit (22%). Results Mean age was 59 +/- 15 (range 22-86) years, with 71% men and 13% re do sternotomy after a previous cardiac procedure. Mean cardiopulmonary bypa ss time was 196 +/- 50 minutes. Mean HCA with RCP time was 42 +/- 12 minute s (range 1984). Mean cardiac ischemic time was 140 +/- 45 minutes. Eleven p ercent of patients presented with a preoperative neurologic deficit, and 5% developed a new cerebrovascular accident after dissection repair. The in-h ospital death rate was 9%. Excluding the patients who presented neurologica lly unresponsive or with ongoing cardiopulmonary resuscitation (n = 5), the death rate was 4%. In six patients adverse cerebral outcomes were potentia lly avoided when immediate surgical fenestration was prompted by a sudden c hange in the EEG during cooling. Forty-five percent of neuromonitored patie nts required greater than 30 minutes to achieve EEG silence. Conclusion The authors have shown that the surgical integration of sinus se gment repair or aortic root replacement, the use of EEG monitoring, partial or total arch replacement using RCP, routine antegrade graft perfusion, an d the uniform use of transesophageal echocardiography substantially decreas e the death and complication rates of acute type A dissection repair.