Prognosis after aortic root replacement with cryopreserved allografts in adults

• Published in: The Annals of thoracic surgery Vol. 75; no. 5; pp. 1482 - 1489
• Main Authors: Takkenberg, Johanna J.M., Eijkemans, Marinus J.C., van Herwerden, Lex A., Steyerberg, Ewout W., Lane, Mary M., Elkins, Ronald C., Habbema, J.Dik F., Bogers, A.d J.J.C.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01-05-2003; Elsevier Science
• Subjects: Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Aortic Valve - transplantation; Biological and medical sciences; Cryopreservation; Disease-Free Survival; Female; Humans; Life Expectancy; Male; Medical sciences; Middle Aged; Models, Statistical; Postoperative Complications; Prognosis; Proportional Hazards Models; Prosthesis Failure; Reoperation; Risk Factors; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgery of the heart; 35; Human; Life expectancy; Prognosis; Mortality; Homograft; Risk analysis; Morbidity; Metaanalysis; Cryopreservation; Surgery; Graft; Simulation model; Aortic valve
• ISSN: 0003-4975; 1552-6259
• DOI: 10.1016/S0003-4975(02)04722-7

Aortic root replacement with cryopreserved allografts is associated with excellent hemodynamics, little endocarditis, low thromboembolic event rates, and no need for anticoagulation. There is, however, concern regarding the long-term durability of this valve substitute, especially in younger patients. Meta-analysis and microsimulation were used to calculate age-specific long-term prognosis after allograft aortic root replacement based on current evidence.
Our center’s experience with cryopreserved allograft aortic root replacement in 165 adult patients was combined in a meta-analysis with reported and individual results from four other hospitals. Using this information, the microsimulation model predicted age- and gender-specific total and reoperation-free and event-free life expectancy.
The pooled results comprised 629 patients with a total follow-up of 1860 patient-years (range 0 to 12.8 years). Annual risks were 0.6% for thromboembolism, 0.05% for bleeding, 0.5% for endocarditis, and 0.5% for nonstructural valve failure. Structural allograft failure requiring reoperation occurred in 15 patients, and a patient age–specific Weibull function was constructed accordingly. Calculated total life expectancy varied from 27 years in a 25-year-old to 12 years in a 65-year-old male; corresponding actual lifetime risk of reoperation was 89% and 35%, respectively.
Cryopreserved aortic allografts have an age-related limited durability. This results in a considerable lifetime risk of reoperation, especially in young patients. The combination of meta-analysis and microsimulation provides an appropriate tool for estimating individualized long-term outcome after aortic valve replacement and can be useful both for patient counseling and prognostic research purposes.