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BARCELONA -- For patients with coronary artery disease (CAD), stenting based on fractional flow reserve (FFR) measurement leads to better outcomes than medical therapy alone, researchers reported here.

The FAME 2 trial -- which was stopped early because of an excess of urgent revascularizations among those on medical therapy -- showed that at 2 years, stenting based on FFR in these patients reduced the risk of a composite of death, MI, or urgent revascularization by 61%, according to , of O.L.V. Ziekenhuis in Aalst in Belgium, and colleagues.

The advantage was driven by the reduction in urgent revascularization, they reported here at the European Society of Cardiology meeting and also online in the .

"In patients with stable CAD, PCI is superior to medical therapy provided that FFR is used to guide the procedure and if second-generation drug-eluting stents are implanted," De Bruyne said during a press briefing.

, of the University of Cincinnati, who was not involved in the study, called it a "potential game changer."

"It's a sea change from the way clinicians have been practicing previously, based on the original COURAGE trial, which told us that maximal medical therapy for stable angina was sufficient," Becker said.

PCI is the preferred treatment in acute coronary syndromes (ACS), but it hasn't yet been shown to reduce hard endpoints in stable coronary artery disease (CAD). Although the COURAGE trial showed that PCI didn't prevent death or MI in this population, interventionalists have speculated that better identification of problematic lesions could improve those hard endpoints.

The FAME 2 study enrolled 1,220 stable CAD patients from 28 sites in Europe and North America, and they were tracked in three groups.

Those with a stenosis that had an FFR value of 0.80 or lower were randomized to either PCI with a second-generation drug-eluting stent (DES), or to medical therapy alone. The remaining 332 patients whose FFR scores were higher than 0.80 were put on medical therapy only.

The trial stopped recruitment early, at 7 months, because of a highly significant between-group difference favoring PCI.

The researchers found that at 2 years, the primary composite endpoint of death, MI, or urgent revascularization was significantly lower with PCI than with medical therapy alone (8.1% versus 19.5%, HR 0.39, 95% CI 0.26-0.57, P<0.001).

The finding was driven by a lower rate of urgent revascularization, the researchers reported (4% versus 16.3%, HR 0.23, 95% CI 0.14-0.38, P<0.001).

In a landmark analysis, the rate of death or MI was significantly lower in the PCI group than with medical therapy between 8 days and 2 years (4.6% versus 8%, HR 0.56, 95% CI 0.32-0.97, P=0.037).

"Although there was no significant between-group difference in the overall rate of death or MI, patients who underwent PCI, as compared with those who received medical therapy alone, had a significant reduction in the rate of death or MI after the initial 7 days following randomization," they wrote.

In patients with an FFR above 0.80 who were assigned to the registry, the rate of the primary endpoint remained low, at 9%, which was comparable to the rate seen in the PCI group.

, of the University of Massachusetts, noted in an accompanying editorial that the decision to stop the trial early without a difference in hard endpoints was highly criticized, "given that patients were often aware of their angiographic findings, a factor that could have lowered the threshold for revascularization in patients with FFR-positive stenoses in the medical-therapy group."

But the fact that the outcome in the registry group was "nearly identical to that in the PCI group [reaffirms] the powerful negative predictive value of the FFR," he wrote, dismissing criticism for stopping the trial early.

Although overall mortality was similar in all three groups, he said it is "hard to accept the contention that periprocedural MI, as defined in the FAME 2 study, constitutes an insignificant risk whose contribution to an overall hard endpoint should be discounted."

A Role for FFR in NSTEMI?

A second, earlier-stage presentation at the meeting focused on the use of FFR in patients with MI.

In the FAMOUS-NSTEMI trial, more patients who had FFR screening were able to avoid stenting or surgery compared with those who went directly into the cath lab, according to , of the University of Glasgow in Scotland, and colleagues.

They simultaneously reported their findings .

A total of 350 NSTEMI patients from six hospitals in the U.K. were randomized to either the regular clinical course with drug therapy, stents, or surgery, or to have an FFR measurement to refine the treatment decision. Interventionalists performed revascularization if the FFR was 0.80 or less and sent patients to medical therapy if it was higher.

Berry and colleagues found that FFR changed the treatment decision in 21.6% of these patients.

Significantly more patients in the FFR group ended up having medical therapy than those who didn't have an FFR measurement (22.7% versus 13.2%, P=0.022).

Revascularization remained lower in the FFR group at 1 year (79% versus 86.8%, P=0.054), and quality of life also tended to be better in the FFR group at this point in time, Berry said.

There was a trend toward reduced length of hospital stay, and overall costs were similar in both groups because even though the initial costs of FFR were higher, reduced hospital stay compensated for it, the researchers said.

Berry concluded that a bigger study is needed to definitively assess whether FFR-guided treatment will improve long-term survival and well-being in NSTEMI patients.

Kurt Huber, MD, a spokesperson for the ESC, said the findings confirm what many interventionalists have thought -- that "FFR is an extremely important method for finding out which lesion has to be treated and which can be left alone."

"This has been done by many cath labs already and these data are extremely promising," Huber told 麻豆传媒. "This clearly shows that if you don't treat a nonsignificant lesion that can be found by FFR, it is safer for the patient. Conservative medical therapy in patients with nonsignificant stenosis seems to be preferable over an intervention in this specific situation."