SAN FRANCISCO -- When treatment of coronary lesions was guided by fractional flow reserve (FFR) plus angiography rather than angiography alone, the two-year risk of death or myocardial infarction was significantly lower, researchers reported here.
Moreover, using FFR to more precisely identify patients likely to benefit from stenting was also a more cost-effective strategy, according to William F. Fearon, MD, associate director of interventional cardiology at Stanford University Medical Center.
Action Points
- Explain to interested patients that angiography is the standard diagnostic imaging study used to assess coronary lesions. This report describes use of an approved add-on diagnostic test.
- Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered preliminary until published in a peer-reviewed journal.
The average cost of angiography-guided stenting was $6,007 versus $5,332 for FFR-guided procedures (P<0.001), Fearon said in announcing two-year results of the FAME study at the Transcatheter Cardiovascular Therapeutics (TCT) meeting.
The absolute difference in the composite endpoint of death or myocardial infarction was 4.3% which was significant (P=0.03), he said.
But the difference in the other combined endpoint of death, MI, or repeat revascularization, which favored FFR at one year, was no longer statistically significant at two years, (P=0.07).
Of the individual endpoints of death, MI, or repeat revascularization (CABG or PCI), only MI was significantly reduced in the FFR group.
Nonetheless, Fearon said the two-year results demonstrate that the benefit of FFR was durable.
One-year results, which also revealed a clinical and economic benefit with FFR, were reported at TCT 2008 and were published last January in the New England Journal of Medicine ().
The trial randomized 1,005 patients with multivessel coronary artery disease to undergo stenting guided by angiography or by angiography plus FFR.
Patients randomized to angiography-guided procedures all were treated with stents, while patients in the FFR group only received stents if the FFR in the affected vessel was less than 0.80, Fearon said.
FFR, he said, provides a more precise measure of the narrowing of the artery because it is based on the ratio of distal pressure to proximal pressure in the target vessel.
In the trial, FFR was measured using St. Jude Medical's PressureWire Certus technology.
Asked about applicability of the FAME results to clinical practice, Stephen G. Ellis, MD, of the Cleveland Clinic Foundation, said FFR is useful when angiography results are equivocal, but he said such ambivalence is unusual among experienced interventional cardiologists.
"We usually recognize the lesions that require stenting," he said.
Ellis noted, however, that the Cleveland Clinic does have FFR available and that its use has been increasing.
Ellis was not involved in the study but he served as a discussant.
Disclosures
The FAME trial was supported by unrestricted research grants from Radi Medical Systems and Stichting Vrienden van het Hart Zuidoost Brabant.
Medtronic provided limited financial support to some centers by tailoring the price of the Endeavor stents to the local reimbursement system.
The two-year follow-up was supported by St. Jude Medical.
Fearon reported consulting fees from Abbott Vascular.
Primary Source
Transcatheter Cardiovascular Therapeutics
Source Reference: Fearon, W et al "FFR vs. angiography for multivessel evaluation FAME 2-year followup" TCT 2009.