Whilst the role of PCI in the treatment of acute coronary syndromes is rarely debated these days, its use in patients with stable angina remains less certain, particularly since the COURAGE trial which failed to demonstrate a prognostic benefit when compared to optimal medical therapy. However, few patients in COURAGE had any functional assessment of their coronary stenoses, with the decision to intervene made on angiographic appearances alone.
In the FAME II study, pressure-wire derived fractional flow reserve (FFR) measurements were used to assess the functional significance of lesions with patients then randomised to PCI or optimal medical therapy if an FFR reached significance at ≤0.80. Patients with an FFR >0.80 were enrolled in a registry and managed with medical therapy. The primary end point was a composite of death, myocardial infarction, or urgent revascularization. Recruitment was halted prematurely by the safety committee after enrolment of 1220 (888 who underwent randomization and 332 enrolled in the registry) out of a projected 1632 patients. Follow-up was also cut from a planned 2 years to a mean of 7 months, all due to a highly statistically significant difference between the two study arms.
FFR guided PCI reduced the event rate from 12.7% in the medical-therapy group to 4.3% in the PCI group (HR with PCI, 0.32; 95% CI, 0.19 to 0.53; P<0.001). This difference was driven almost exclusively by an increase in the rate of urgent revascularization in the medical-therapy group (1.6% vs. 11.1%; HR, 0.13; 95% CI, 0.06 to 0.30; P<0.001) with their being no significant differences in the rates of MI or death from any cause (P=0.89 and P=0.31, respectively). The medical therapy registry group had very low overall event rates and confirmed this as a generally low risk population.
In patients with stable coronary artery disease, FFR-guided PCI decreased the need for urgent revascularization but had no effect on rates of MI or death. In patients without significant ischemia, outcomes were good with optimal medical therapy alone.
- De Bruyne B, Pijls NH, Kalesan B, Barbato E, Tonino PA, Piroth Z, Jagic N, Mobius-Winckler S, Rioufol G, Witt N, Kala P, MacCarthy P, Engström T, Oldroyd KG, Mavromatis K, Manoharan G, Verlee P, Frobert O, Curzen N, Johnson JB, Jüni P and Fearon WF. Fractional flow reserve-guided PCI versus medical therapy in stable coronary disease. N Engl J Med. 2012 Sep 13;367(11):991-1001.