Background: This study evaluates the cost-effectiveness of 64-slice computed tomography coronary angiography (CTCA) as an alternative to invasive diagnostic coronary angiography (CA) in an elective outpatient setting for patients otherwise referred to invasive diagnostic coronary angiography.
Methods: Taking the perspective of the Australian health system we used a decision analytic model to integrate data on test accuracy along with complication rates, health state preference weights and health care costs. The analysis is pre-test risk stratified based on Bayes' theorem of conditional probability. Incremental cost-effectiveness ratios (ICER) are the study endpoints expressed as incremental costs per quality adjusted life year (QALY) gained.
Results: The results indicate that CTCA is a cost-saving strategy offering a higher health related quality of life up to approximately 65% pre-test risk of coronary artery disease (CAD). Above that threshold the model predicts a cost-utility trade-off with every gain in health related quality of life through the use of CTCA as a rule-out test being associated with additional costs when compared to invasive diagnostic CA.
Conclusion: This health economic analysis predicts computed tomography coronary angiography to be a cost-effective rule-out strategy in symptomatic patients at low to intermediate risk of significant obstructive coronary artery disease otherwise referred to invasive diagnostic CA.