The cost-effectiveness of myocardial perfusion imaging for the detection of significant coronary artery disease in patients undergoing pre-operative liver transplantation evaluation: economic modeling and decision analysis with validation by a retrospective observational study in 215 consecutive patients.

Purpose: Screening for significant coronary artery disease (CAD) in pre-liver transplant candidates is controversial due to concerns about screening test (ST) accuracy and cost-effectiveness (CE). This economic evaluation modeling study was performed to determine the CE of the widely available CAD screening test strategies including a no imaging CAD screening test strategy (NST). dobutamine stress echo, myocardial perfusion imaging, invasive cardiac catheterization, with invasive coronary FFR as the gold standard diagnostic test. Materials and Methods: A retrospective review of 215 consecutive transplant candidates was conducted to define model inputs for decisional analysis. Perspective: a tertiary academic medical center in the USA. Other sources: extant literature review, including systematic reviews and meta-analysis, hospital accounting and clinical testing performance certification data and expert panel input using a modified Delphi exercise. Outcome measures: net monetary benefit (NMB), willingness-to-pay criteria, incremental health care cost and quality adjusted life-years (QALY’s) gained, threshold analysis, cost-effectiveness acceptability curves, one-way and probabilistic sensitivity analysis with Monte Carlo simulation. Half-cycle correction for both costs and outcome effects assuming discount rate of 3.5%. Markov node cycle length: one year with a 20-year time frame and a Dirichlet distribution structure allowing for a fully probabilistic transition matrix.

Results: MPI is the optimal strategy with a net effect of 4.56 QALYs and an incremental effect of 1.05 QALY’s gained at an incremental cost of $31,423 equivalent to $29,905 per QALY gained (ICER) when compared to the undominated NST. MPI resulted in a NMB of $30,830 assuming a WTP of $50,000 at a cost per QALY of $43,233. MPI demonstrated extended dominance over the alternative screening test stratagems included in the model. According to sensitivity analysis the results are dependent only upon the prevalence of CAD in the population under investigation but were insensitive to screening test and interventional costs.

Conclusions: When compared to a NST, MPI may be more cost-effective than other imaging modalities in the evaluation of liver transplant candidates.