SAN FRANCISCO—Two-year follow-up of the FAME study confirmed the durability of improved outcomes at one-year for patients undergoing fractional flow reserve (FFR) prior to PCI, according to a presentation at the annual Transcatheter Cardiovascular Therapeutics (TCT) meeting.
FFR uses a pressure wire to determine the functional severity of coronary stenoses. Patients in the FAME study, who had two or more lesions and the operator deemed warranted PCI, were randomized to either FFR- or angiography-guided PCI.
The results demonstrated that patients who received FFR-guided treatment had increasingly superior outcomes over time. The two patient groups had a difference in patient death and MI of 3.8 percent after 12 months and 4.3 percent after two years.
“The key difference between one and two years was that the rate of MI is significantly lower in the FFR-guided arm compared to the angiography-guided arm,” lead investigator William Fearon, MD, told Cardiovascular Business News. “There was a trend toward that at one year and that risk continued to be separated by the curves. And there was a 34 percent risk reduction in the rate of MI at two years.”
Fearon also noted that at two years there was a strong trend toward lower rates of the composite of death, MI and repeat revascularization, occurring in about 17 percent of the FFR-guided arm and 22 percent in the angiography-guided arm.
In clinical practice, there is a typical false-negative rate of approximately 5-10 percent. However, Fearon noted that in his practice it is about 5 percent or less.
At two years, patients in the FFR-guided arm had less angina, although the difference between the two arms was not significant.
“One might expect the FFR-guided arm would have higher angina, because you left angiographic disease behind that could cause chest pain. To see similar rates would have been reassuring, but to see better rates is even more reassuring,” said Fearon, associate director of intervetnional cardiology at Stanford University Medical Center in Calif.
He concluded by saying that there is no signal to suggest that deferred lesions are likely to be responsible for late MI or to progress and require repeat revascularizations.
Researchers found that only one lesion out of 500 that were deferred PCI treatment in the FFR-guided arm could be attributed to causing an MI.
“It is very reassuring that the pressure wire not only helps guide you in the immediate timely procedure, but it also helps forecast what might happen and truly identifies lesions that are stable and can be treated medically,” Fearon said.