Elephant trunk and frozen elephant trunk in reconstructive surgery of the aortic arch. Meta-analysis of immediate and long-term results

Elephant trunk procedure was first used for thoracic aortic aneurysm. Frozen elephant trunk technique was developed later to optimize aortic remodeling in type A aortic dissection. This meta-analysis compares the results of elephant trunk and frozen elephant trunk procedures. We analyzed the MEDLINE, Embase, Cochrane and Web of Science databases. Primary endpoints were stroke and spinal cord ischemia after surgery, open surgery, and stenting of descending aorta after the first surgery. Secondary endpoints included incidence of Marfan syndrome, aneurysm as an indication for surgery, acute type A aortic dissection and 30-day mortality. The meta-analysis was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analysis) 2020 criteria. We analyzed treatment outcomes in 1949 patients after aortic arch replacement via elephant trunk and frozen elephant trunk procedures. Postoperative stroke was significantly less common after elephant trunk surgery (odds ratio (OR) 0.59; 95% confidence interval (CI) 0.37—0.94; I2=38%; p=0.03). There were no differences in spinal cord ischemia (OR 0.55; 95% CI 0.23—1.28; I2=46%; p=0.16) and 30-day mortality (OR 1.33; 95% CI 0.89—1.98; I2=0%; p=0.16). Stenting after primary surgery was less common after elephant trunk surgery (OR 0.55; 95% CI 0.32—0.94; I2=54%; p=0.03). Redo open surgery was less common after frozen elephant trunk procedure (OR 2.39; 95% CI 1.44—3.98; I2=0%; p=0.0008). We found comparable results in both groups. Stenting after primary surgery was more common after frozen elephant trunk surgery.