sumptions and scenarios that were developed through discussions with the committee and other experts.
Aside from medical therapies, heart transplantation is currently the only clinical option for patients suffering from end-stage heart failure. As discussed in Chapter 4, the number of potential heart transplant recipients greatly exceeds the available supply of donor hearts. Several types of long-term mechanical circulatory support devices are being developed in order to treat these heart failure patients. Currently, the ventricular assist device has the best prospect of being available in the near future. Although this device will potentially be able to serve a large number of heart failure patients, it is unlikely to work satisfactorily for the subset of patients with both right and left heart failure. Hence, several groups in the United States, four of which have NHLBI support, are continuing their efforts to develop a total heart replacement device.
In order to address the issue of the level of resources that society should devote to research and development of the TAH, it is important to develop an understanding of the likely costs and outcomes of such investments. Given the uncertainties of such a question, however, it is not obvious that a quantitative, as opposed to qualitative, approach is either necessary or preferred. Nonetheless, the committee chose to have data gathered and compiled to illustrate some of the quantitative dimensions of the issue.
The information was compiled in a cost-effectiveness analysis (CEA) framework for two separate but related issues:
The future cost-effectiveness of the artificial heart in use, compared to alternative surgical and medical therapies.
The cost-effectiveness of alternative research and development strategies for developing TAHs.
The framework and estimates associated with each of these issues are presented in the following sections. Although the R&D investment must come before the TAH is available for use, it is useful to consider first the cost-effectiveness in use since the diffusion of the device becomes the benefit of the investment.
To estimate the cost-effectiveness of the artificial heart in routine use, a Markov simulation model was used, permitting variations in assumptions