Malperfusion as a Predictor for a Higher Reoperation Rate at the Distal Aorta after Acute Type A Aortic Dissection - A Long-Term Follow-Up

Objective: This study evaluates the preoperative and initial operative predictors influencing the long-term reoperation rate at the distal aorta of patients undergoing surgery for acute type A aortic dissection (ATAAD).

Methods: Between January 2000 and May 2014, 247 consecutive patients (female 32.4%, mean age 62.0 ± 12.2) with ATAAD underwent surgical replacement of the ascending aorta including hemi arch in 157 (63.6%), total arch in 23 (9.3%), frozen elephant trunk in 10 (4.0%) and elephant trunk in 2 (0.8%) patients. Of these, 70.9% (n = 175) underwent supracoronary aortic replacement and 29.2% (n = 72) underwent root replacement (Bentall 20.7%, n = 51 and valve-sparing procedures 8.5%, n = 21). We retrospectively analyzed preoperative, operative and postoperative variables for reoperation including the neurological and hemodynamical status, etiology and extensiveness of the dissection, malperfusion, type of operation and postoperative complications using Kaplan-Meier method and univariate Cox regression.

Results: The 30-day mortality rate was 20.2% (50 patients). Cerebrovascular events have been documented in 19.8% (n = 49), spinal cord injury in 0.8% (n = 2). Actuarial survival at 1, 5 and 10 years was 72.8%, 57.7%, and 46.1% respectively. Freedom from reoperation at the distal aorta (frozen elephant trunk 0.40%, n = 1; endovascular aortic repair 0.81%, n = 2; thoracic endovascular aortic repair 4.45%, n = 11; renal artery stenting 0.40% n = 1; thoracic aortic replacement 0.40%, n = 1) was at 1, 5 and 10 years 97.6%, 89.3% and 84.0%, respectively. Statistical significant predictors for reoperation at the distal thoracic aorta are as follows: Critical Preoperative State (defined by Euroscore II) (p = 0.010; OR 4.1), preoperative malperfusion cerebral (p = 0.014; OR 15.9), spinal (p = 0.001; OR 38.7), and abdominal (0.018; OR 13.6). Additionally preoperative aphasia as a clinical correlative of cerebral malperfusion was siginificant (p = 0.028; OR 4.2).

Conclusion: This study shows that malperfusion and hemodynamic instability are independent risk factors for a higher reoperation rate at the distal aorta in a long-term follow-up, whereas the etiology and the distal extensiveness of the dissection did not affect the reoperation rate. Therefore patients with preoperative malperfusion should be operated more aggressively and should also be followed-up by CT-imaging more frequently to be able detect the expansion of the false lumen.