Hospital Results of a Single Center Database for Stentless Xenograft Use in a Full Root Technique in Over 970 Patients

Our aim was to analyse the hospital outcome for the worldwide largest series of stentless bioroot xenografts (Medtronic Freestyle) as full root replacement in a single centre over a period of 18 years. Retrospective data analysis was performed for the entire cohort of patients undergoing aortic root surgery with the Medtronic Freestyle valve prosthesis. Logistic regression analysis was performed to analyse predictors of in-hospital mortality. 971 patients underwent aortic full root replacement with the Medtronic Freestyle valve in the period from 1999–2017, with an average age of 68.8 ± 10.3y and gender distribution of 608:363 (male:female). Concomitant surgery was performed in 693 patients (71.4%). In-hospital all-comers mortality was 9.8% (95 patients), with the respective highest risk profiles including dissections (6.4%), endocarditis (5.6%) and re-do procedures (12.5%). In-hospital mortality for elective patients was 7.6% while isolated aortic root replacement demonstrated a mortality of 3.6%. Logistic regression analysis demonstrated age (OR 1.05, p = 0.005), dissection (OR 5.78, p < 0.001) and concomitant bypass surgery (OR 2.68, p < 0.001) as preoperative risk factors for the entire cohort. Postoperative analysis demonstrated myocardial infarction (OR 48.6, p < 0.001) and acute kidney injury (OR 20.2, p < 0.001) to be independent risk factors influencing mortality. This analysis presents a work-through of all patients with stentless bioroot treatment without positive selection in a high-volume clinical center with the largest experience world-wide for this form of complex surgery. Isolated aortic root replacement could be performed at acceptable operative risk for this technically-challenging procedure.