The learning curve effect on outcomes with frozen elephant trunk technique for extensive thoracic aorta disease

OBJECTIVE: The purpose of this study was to analyze the learning curve effect on hospital mortality, postoperative outcomes, freedom from reintervention in the aorta and long-term survival after frozen elephant trunk (FET) operation. METHODS: From July 2009 to June 2018, 79 patients underwent surgery with the FET technique. They had type A aortic dissection (acute 7.6%, chronic 33%), type B aortic dissection (acute 1.26%, chronic 34.2%), and complex thoracic aortic aneurysm (24%). 27.8% were reoperations and 43% received concomitant cardiac procedures. To compare the results, the sample was divided into group 1 (G1) (first half of the sample - operations from 2009 to 2014) and group 2 (G2) (first half of the sample - operations from 2015 to 2018). RESULTS: The in-hospital mortality was 20.25%, 30.7% for G1 and 10% for G2 (P = .02). The mean cardiopulmonary bypass time, myocardial ischemia time, and selective cerebral perfusion at 25°C time were 154 ± 31, 118 ± 32, and 59 ± 12 minutes, respectively, similar for both groups. Stroke and spinal cord injury occurred in four and two patients, with no difference between groups (P = .61 and P = .24). The necessity for secondary intervention on the downstream aorta for both groups was also similar (P = .136). Five of sixty-three surviving patients died during the follow-up period and the estimated survival rate was different between groups 49% vs 88% (P = .007). CONCLUSION: The learning curve with the FET procedure had a significant impact on hospital mortality and midterm survival over the follow-up period, albeit did not influence the freedom from reintervention on the downstream aorta.