Initial and long-term results of allografts and xenografts in surgical treatment of aortic root and ascending aneurysm
AbstractAim. The aim of our study was to estimate initial and long-term outcomes of ascending aortic and root replacement with either xenograft or allograft in patients with chronic aortic aneurysm.
Material and methods. Forty-five patients were enrolled in the study from January 2017 to May 2023. In 23 patients a Medtronic Freestyle xenograft was applied, while 22 patients underwent allograft implantation. Early safety, clinical efficacy were analyzed using VARC-3 and ICHOM criteria at exact time points using non-parametric statistics. Time-to-event survival analysis was performed using log-rank test and Kaplan-Meier curves.
Results. Patients from both groups demonstrated excellent early results with zero 30-day mortality. There were no incidence of myocardial infarction, deep sternal wound infection and pacemaker implantation. One patient after xenograft implantation was complicated with ischemic stroke. Resternotomy for bleeding was required in one patient from both groups. Patients with either allograft or xenograft demonstrated 100% freedom from structural deterioration, redo surgery, endocarditis and pacemaker implantation during the whole follow-up period. Allograft implantation was associated with significantly better survival compared with xenograft (100 vs 78.3%, OR 10.53; 95% CI 0.0128–0.3839; р=0,036) and better quality of life (95% CI -22.76, -2.244; р<0.05) two years after surgery. The number of patients with left ventricle hypertrophy was significantly higher after xenograft implantation regardless the overall reduction in left ventricle hypertrophy in both groups compared with preoperative variables (р=0.03). The maximum and average pressure gradient at the aortic root after surgery and one year after surgery was statistically significantly lower after allograft implantation [16.0 (11.8–21.0) and 7.0 (5.0–10.0) vs 7.0 (6.0–10.0) and 3.0 (3.0–5.0); 95% CI (4.326–13.67) and 95% CI (1,844–6,156); p<0.05]. The analysis of survival to the endpoints was carried out in 6-, 12-, 18-, 24-, 36-, 48- the monthly period after surgery. Expected survival in the allograft group through 6, 12, 18, 24, 36, 48 for a month and beyond, it was 100%. Survival rate in the xenograft group over the same time periods – 82,6; 82,6; 82,6; 77,7; 77,7; 77.7% (log-rank test, p=0.02).
Conclusion. Ascending aortic and root replacement with either xenograft or allograft demonstrated excellent early results with zero 30-day mortality and lower rate of complications in selected patients. Clinical efficacy, quality of life and time-to-event analysis may justify in favor of allograft ascending and root replacement, although it should be studied further. Allograft aortic replacement showed better hemodynamic profile with regard to significantly lower number of patients with LV hypertrophy and lower peak and mean pressure gradients on aortic root.
Keywords: aortic aneurysm; xenograft; allograft; prosthetics of the root and ascending aorta
Funding. The study had no financial support.
Conflict of interest. The authors declare no conflicts of interest.
Authors’ contribution. Study conception and design – Nuzhdin M.D., Komarov R.N., Fokin A.A.; collection and processing of material – Nuzhdin M.D., Malinovsky Yu.V.; statistical data processing – Galchenko M.I.; draft manuscript preparation – Nuzhdin M.D., Galchenko M.I., Malinovsky Yu.V.; manuscript revision – Nuzhdin M.D., Komarov R.N., Galchenko M.I., Malinovsky Yu.V., Fokin A.A.
For citation: Nuzhdin M.D., Komarov R.N., Fokin A.A., Galchenko M.I., Malinovsky Yu.V. Initial and long-term results of allografts and xenografts in surgical treatment of aortic root and ascending aneurysm. Angiology and Vascular Surgery. Journal named after Academician A.V. Pokrovsky. 2026; 32 (1): 72–84. DOI: https://doi.org/10.33029/1027-6661-2026-32-1-72-84
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