An economic evaluation along the FAME trial in the context of the US healthcare system was performed. The incremental cost-effectiveness ratio (ie, the net incremental cost of the FFR-guided and angiography-guided strategies divided by the net incremental health outcomes of each strategy) was calculated. The time horizon was 1 year (ie, the duration of follow-up in the primary clinical study), and analyses were performed from a societal perspective using direct costs. Given the short time horizon, no discounting was performed. The primary analysis wasa cost-utility analysis (ie, cost versus quality-adjusted life years [QALYs]).
How much costs are included in each strategy?
Costs for each strategy included the initial procedural costs and costs during the 1-year follow-up. The costs of the index procedures were calculated from the actual resource consumption by determining the amount of guiding catheters, regular wires, pressure wires, balloon dilatation catheters, stents, antiplatelet therapy, adenosine, contrastmedia, and hospital days used for each patient’s index procedure. These were multiplied by the cost of each resource in US dollars.
What is QLAYs ?
QLAYs (Quality-Adjusted Life Years) is a measure of health outcomes defined as perfect health minus DALY. QALY combines changes in morbidity (quality) and mortality (amount) in a single indicator.
In the study, QALYs were derived from health-related quality of life and survival during the 1-year time horizon of the trial.
How does QALY in the FFR-guided group compare to the angiography-guided group?
The final result of the study shows that QALYs at 1 year were numerically higher in the FFR-guided arm compared with the angiography-guided arm (0.853 versus 0.838; P0.2).
At 1 year, the rate of major adverse cardiac events (MACE) was 13.2% in the FFR-guided arm and 18.3% in the angiography-guided arm (P=0.02). The rate of death or MI was 7.3% in the FFR-guided arm versus 11.1% in the angiography-guided arm (P=0.04).
Reducing the utilities calculated from the EuroQuol 5 dimension health survey by 10% resulted in 0.748 QALYs on averagefor the angiography-guided group and 0.767 for the FFR group. Increasing the utilities by 10% resulted in 0.914 and 0.938 QALYs, respectively.
The corrected mean utilities in the angiography group were 0.808, 0.895, and 0.896 at baseline, 1 month, and 1year. The respective values in the FFR-guided group were 0.808, 0.887, and0.887 (P0.05 between study groups at all time points). In both groups, mean utilities increased from baseline to 1 month (P0.0001) and remained stable until the end of follow-up.
How many economic cost can reduce by FFR-guided PCI?
The mean index procedural and hospitalization costs were significantly lower in the FFR-guided arm ($13 182±9667 versus $14 878±9509; P<0.0001).<>
Overall costs at 1 year ranged from $2591 to $99 027 in the FFR-guided strategy and from $4445 to $108 404 in the angiography-guided strategy. At 1 year, the mean overall costs were significantly lower in the FFR-guided arm ($14 315±11 109 versus $16 700±11 868; P<0.0001).<>
The bootstrap simulation demonstrated that the FFR-guided strategy is cost-saving in 90.74% and cost-effective (at athreshold of $50 000 per QALY gained) in 99.96% of 5000 bootstrap simulation samples.
Sensitivity analyses varying resource prices by 20% led to cost differences between the study groups of $2042 to $2726 (base case, $2384), always favoring the FFR-guided strategy as being lesscostly.
How does the FFR-guided strategy reduce costs?
The cost savings occur both at the index procedure, primarily owing to a decrease in drug-eluting stent use being a major cost driver, which more than offsets the increased cost of the pressurewire and adenosine, and during follow-up as a result of a decrease in rehospitalization and fewer major adverse cardiac events. About 90% of the total cost occurred at the index hospitalization. However, comparing with the traditional Angiography-guided strategy ≈30% of the overall cost difference between the 2 strategies is generated during follow-up, indicating increasing cost savings even after the initial procedure.
It happens in 90.7% of the samples, and sensitivity analyses varying costs and utilities did not change these results.
The FFR-guided strategy resulted in fewer stents being placed and hence lower costs, despite the costs of the pressurewire and adenosine, and better outcomes because the benefit of the stents was maximized and the risk minimized.
(William F. Fearon, Bernhard Bornschein, Pim A.L., etal. Economic Evaluation of Fractional Flow Reserve Guided Percutaneou Coronary Intervention in Patients With Multivessel Disease. Circulation2010;122;2545-2550)- https://www.ahajournals.org/doi/full/10.1161/circulationaha.109.925396