Cost-effectiveness of cardiovascular magnetic resonance in the diagnosis of coronary heart disease: an economic evaluation using data from the CE-MARC study.

Objective: To evaluate the cost-effectiveness of diagnostic strategies for coronary heart disease (CHD) derived from the CE-MARC study.

Design: Cost-effectiveness analysis using a decision analytic model to compare eight strategies for the diagnosis of CHD.

Setting: Secondary care out-patients (Cardiology Department).

Patients: Patients referred to cardiologists for the further evaluation of symptoms thought to be angina pectoris.

Interventions: Eight different strategies were considered, including different combinations of exercise treadmill testing (ETT), single-photon emission CT (SPECT), cardiovascular magnetic resonance (CMR) and coronary angiography (CA).

Main Outcome Measures: Costs expressed as UK sterling in 2010-2011 prices and health outcomes in quality-adjusted life-years (QALYs). The time horizon was 50 years.

Results: Based on the characteristics of patients in the CE-MARC study, only two strategies appear potentially cost-effective for diagnosis of CHD, both including CMR. The choice is between two strategies: one in which CMR follows a positive or inconclusive ETT, followed by CA if CMR is positive or inconclusive (Strategy 3 in the model); and the other where CMR is followed by CA if CMR is positive or inconclusive (Strategy 5 in the model). The more cost-effective of these two rests on the threshold cost per QALY gained below which health systems define an intervention as cost-effective. Strategy 3 appears cost-effective at the lower end of the threshold range used in the UK (£20 000 per QALY gained), while Strategy 5 appears cost-effective at the higher end of the threshold range (£30 000 per QALY). The results are robust to various sources of uncertainty although prior likelihood of CHD requiring revascularisation and the rate at which false negative patients are eventually appropriately identified do impact upon the results.

Conclusions: The CE-MARC study showed that CMR had superior diagnostic accuracy to SPECT and concluded that CMR should be more widely used in the investigation of patients with CHD. The economic evaluation results show that using CMR is also a cost-effective strategy and supports the wider adoption of this modality.