Usefulness of microsimulation to translate valve performance into patient outcome: patient prognosis after aortic valve replacement with the Carpentier-Edwards supra-annular valve.
OBJECTIVE
Numerous reports have been published documenting the results of aortic valve replacement. It is often not easy to translate these outcomes involving the condition of the valve into the actual consequences for the patient. We previously developed an alternative method to study outcome after aortic valve replacement that allows direct estimation of patient outcome after aortic valve replacement: microsimulation modeling. The goal of this article is to provide insight into microsimulation methodology and to give an overview of the advantages and disadvantages of simulation methods (in particular microsimulation) in comparison with standard methods of outcome analysis.


METHODS
By using a primary dataset containing 1847 patients and 14,429 patient-years, advantages and disadvantages of standard methods of outcome analysis are discussed, and the potential role of microsimulation is illustrated by means of a step-by-step explanation of building, testing, and using such a model.


RESULTS
Total life expectancy, event-free life expectancy, and reoperation-free life expectancy for a 65-year-old male patient were 10.6 years, 9.2 years, and 9.8 years, respectively. Lifetime risk of reoperation due to structural valve deterioration was 13.3%.


CONCLUSIONS
Microsimulation is capable of providing accurate estimates of age-related life expectancy and lifetime risk of reoperation for patients who underwent aortic valve replacement with the Carpentier-Edwards supra-annular valve. It provides a useful tool to facilitate and optimize the choice for a specific heart valve prosthesis in a particular patient.
van Geldorp
Martijn W A
MW
Department of Cardio-thoracic Surgery, Erasmus University Medical Center, Rotterdam, The Netherlands. m.vangeldorp@erasmusmc.nl
Jamieson
W R Eric
WR
Kappetein
A Pieter
AP
Puvimanasinghe
John P A
JP
Eijkemans
Marinus J C
MJ
Grunkemeier
Gary L
GL
Takkenberg
Johanna J M
JJ
Bogers
Ad J J C
AJ
D000368:Aged; D001021:Aortic Valve / Q000601:surgery*; D001705:Bioprosthesis; D003198:Computer Simulation; D005260:Female; D006350:Heart Valve Prosthesis; D006801:Humans; D008297:Male; D011379:Prognosis; D011474:Prosthesis Design