Cost-effectiveness of intracoronary flow velocity measurements and myocardial perfusion scintigraphy for management of intermediate coronary lesions

Background: Coronary flow velocity reserve (CFVR) is an alternative for myocardial perfusion scintigraphy (SPECT) in assessing functional severity of coronary lesions. For the acceptance of CFVR in daily clinical decision-making, cost-effectiveness must be proven.

Aim: Economic evaluation of different diagnostic management strategies using CFVR compared with SPECT for making decisions regarding use of PTCA of an intermediate coronary lesion in patients with multivessel disease.

Methods: The incremental cost-effectiveness analysis was based on data from a prospective multicentre study in 201 patients with multivessel coronary artery disease. Four management strategies, assuming performance of angioplasty after positive test result(s), were compared: SPECT alone, CFVR alone (cut-off value of 2.0), and combined strategies of SPECT and CFVR with one ('extensive') or two ('restrictive') positive test(s). Probabilistic sensitivity analyses were performed using Monte Carlo simulation. Primary outcome was the probability of a cardiac event-free first year with respect to the intermediate lesion.

Results: A 10% event rate was observed, which was predominantly associated with ischaemia-driven revascularisations. A strategy based on CFVR was most effective. The restrictive strategy had the lowest costs and was most cost-effective; with increasing willingness-to-pay values (above €20,000) a CFVR-alone strategy became equally cost-effective.

Conclusion: It is mandatory to measure CFVR to decide upon angioplasty of the intermediate lesion in patients with multivessel coronary artery disease. This decision can be based on the restrictive strategy (i.e. performance of PTCA in case of abnormal test results of both SPECT and CFVR) or solely on CFVR, depending on society's willingness-to-pay to prevent cardiac events.