Outcomes of Patients with Acute Type-A Aortic Dissections and Primary Tear Distal to the Innominate Artery

A. van Kampen¹, M. Gerber¹, J. Haunschild², N. Stech¹, M. Misfeld³, S. Leontyev¹, C. Etz⁴, M. Borger^1
1Leipzig Heart Center, Leipzig, Sachsen ²Rostock University Hospital, Rostock, Mecklenburg-Vorpommern ³Department of Cardiac Surgery, Leipzig Heart Centre, University of Leipzig, Leipzig,, Leipzig, Sachsen ⁴University Rostock, Rostock, Saxony

Purpose: In acute type A aortic dissection (ATAAD), surgical strategies often depend on primary tear location and dissection extent. Data are scarce on ATAAD with primary tear in arch or descending aorta. Herein, we examined early and late outcomes of patients with ATAAD and primary tear distal to the innominate artery.

Methods: By interrogation of our institutional aortic dissection database, we included all adult (≥18 years) patients operated between 1994-2020 for ATAAD at our center. We excluded re-operations and iatrogenic dissections, as well as those patients with primary entry in the ascending aorta and unspecified/unknown primary tear location. Primary tear sites were identified by review of preoperative CT images and reports, and operative notes. All imaging notes and electronic medical records were reviewed by two independent trained researchers. Surgical repair was conducted as appropriate based on pathology and individual surgeons' decisions, and moderate hypothermia with antegrade cerebral perfusion was utilized whenever feasible. Statistical analysis was performed using R software, including survival analysis with Kaplan-Meier method.

Results: Of 1087 ATAAD patients operated during the study period, we included 170 who fit the in- and exclusion criteria. The mean age was 64.5±12.2 years and 72 patients (42.4%) were female. Upon referral, 114 patients (67.1%) had relevant aortic regurgitation, 71 (41.8%) had a pericardial effusion, and 10 (5.9%) were resuscitated prior to surgery. Supra-aortic malperfusion was present in 23 patients (13.5%), visceral malperfusion in 17 (10%), and extremity malperfusion in 10 (5.9%). Primary tear site was the aortic arch in 138 patients (81.2%), while the others had the primary tear in the descending aorta. Hemi-arch replacement was performed in 68 patients (40%), total arch replacement in 102 (60%), with conventional elephant trunk in 60 (35.3%) and frozen elephant trunk in 16 cases (9.4%). Aortic root replacement was necessary in 47 patients (27.6%). A perioperative stroke occurred in 48 patients (28.2%), 22 (12.9%) had visceral ischemia. In-house mortality was 14.3% (26 patients), and 28 patients (16.5%) were discharged with permanent neurological deficits - 6 (3.5%) with paraplegia. During follow-up, 23 patients (13.5%) needed a re-operation on the thoracic aorta. By Kaplan-Meier estimation, 5-year survival free from re-operation was 50%.

Conclusion: ATAAD with primary entry tear beyond the innominate artery requires complex surgical repair with frequent total arch replacements. Yet, even after comprehensive surgical therapy in a high-volume institution, early morbidity and mortality are high. Re-operations on the aorta during the later follow-up are frequent in this group of patients. Overall, long-term survival remains much lower than in the general population. Further research is needed to determine optimal surgical strategies for patients with this highly complex presentation of ATAAD to improve early and late outcomes.

Identify the source of the funding for this research project: There was no specific funding for this research. A.v.K. is supported by an American Heart Association Postdoctoral Fellowship.