WASHINGTON, DC — In a trial of patients undergoing PCI for acute ST-elevation MI (STEMI), a strategy of further PCI beyond the infarct-related artery guided by fractional flow reserve (FFR) assessments was associated signficant reductions in a composite clinical end point compared with infarct-related-artery–only primary PCI. The benefit, seen for the composite of all-cause mortality, nonfatal MI, any revascularization, or cerebrovascular events at 12 months, appeared to be driven mainly by fewer repeat revascularizations in the FFR-guidance group.
Dr Pieter C Smits (Maasstad Hospital, Rotterdam, the Netherlands) presented these findings from the COMPARE-ACUTE trial at the American College of Cardiology (ACC) 2017 Scientific Sessions. The results were simultaneously published online in the New England Journal of Medicine.
The study showed that "deferring treatment of angiographically significant coronary lesions in non–infarct-related arteries with an FFR >0.8 is safe and efficient," he said, but the study "was not powered to detect low-frequency events such as death, reinfarction, and stroke."
A strategy of complete revascularization in all patients with STEMI and multivessel disease "appears to be safe, but it may not be necessary in all patients," Dr Lars Kober (University of Copenhagen, Denmark) cautioned in an accompanying editorial.
Two ongoing larger trials with hard end points should help determine which patients would benefit.
"In my opinion, in my own practice, I'm not going to jump on the bandwagon wholesale until we get hard end points," assigned discussant Dr Nils Johnson (University of Texas Medical School, Houston) told heartwire from Medscape.
But clinical practice is already changing. "We've seen that [FFR-guided multivessel angioplasty] has moved from a class 3 indication to a class 2b indication, as we had some of the trials over the past couple of years. COMPARE-ACUTE is continuing the momentum in that direction," he said.
"Some of it is going to come down to the issue of 'What are we trying to do to these people? Are we trying to make them feel better? Or are we trying to reduce hard end points?' " according to Johnson.
"I think that the two additional ongoing clinical trials will really solidify [guidelines and clinical practice], because right now, looking at hard end points (death, MI, stroke), we really didn't see much of a difference; it was all based upon the repeat revascularizations," cochair Dr Martin B Leon (Columbia University Medical Center, New York) told heartwire .
"Until that's settled, I think its going to take a while before guidelines definitively change, but it's certainly is moving in that direction," he echoed.
885 Patients Randomized
COMPARE-ACUTE enrolled 885 patients aged 18 to 85 who presented with STEMI and had a stenosis of at least 50% severity in a nonculprit coronary artery, seen at 24 centers in the Netherlands, Sweden, Germany, Norway, the Czech Republic, Hungary, Poland, and Singapore.
The patients had a mean age of 62, and 79% were male.
After successful PCI of the STEMI culprit artery, eligible patients were randomly assigned 1:2 to FFR-guided complete revascularization (295 patients) or treatment of the infarct-related artery alone (590 patients).
More patients in the complete-revascularization group had a positive FFR (<0.80), 54% vs 48%, respectively (P=0.08).
At 1 year, MACCE had occurred in more patients in the infarct-only group vs the complete-revascularization group: eight and 21 events per 100 patients, respectively.
12-Month Outcomes, Complete vs Infarct-Artery Only Revascularization
|Outcome||FFR-guided PCI, n (%)||Infarct-artery only PCI, n (%)||HR (95% CI)||P|
|MACCE||23 (7.8)||121 (20.5)||0.35 (0.22–0.55)||<0.001|
|All-cause death||4 (1.4)||10 (1.7)||0.80 (0.25–2.56)||0.70|
|MI||7 (2.4)||28 (4.7)||0.50 (0.22–1.13)||0.10|
|Revascularization||18 (6.1)||103 (17.5)||0.32 (0.20–0.54)||<0.001|
|Cerebrovascular event||0 (0)||4 (0.7)||Not available||Not available|
|Death or MI||11 (3.7)||38 (6.4)||0.57 (0.29–1.12)||0.10|
The complete revascularization procedure added an average of only 6 minutes, and rates of adverse events were low, "which supports the proposition that FFR and revascularization can be safely performed simultaneously, making it possible for patients to avoid additional catheterization procedures," Kober writes.
A third of repeat revascularizations were performed due to acute coronary syndromes, which is consistent with the DANAMI-3-PRIMULTI trial that involved FFR-guided intervention, he observed.
"However, patients included in trials are often at lower risk than those who are not included, and it is uncertain whether these results can be extrapolated to sicker patients, who may be at greater risk for complications associated with a prolonging of the index procedure but may also receive greater benefit with respect to later cardiovascular events."
While Waiting for COMPLETE, FULLREVASC . . .
"There's a lot of heterogeneity . . . around the world in how we approach these patients," Johnson said.
The Complete vs Culprit-only Revascularization to Treat Multivessel Disease After Primary PCI for STEMI (COMPLETE) and FFR-Guidance for Complete Non-Culprit Revascularization (FULL REVASC) clinical trials, each with a planned enrollment of about 4000 patients and primary outcome data expected in a couple of years, are powered to look at death and MI and should provide more answers.
In the meantime, COMPARE ACUTE "is a major step forward. . . . For me, the real hint from the . . . data is the secondary end point of death or MI showed 40% reduction by using an FFR strategy, which didn't reach statistical significance because of the modest sample size," according to Johnson.
Moreover, the lesions were truly clinically intermediate; the average FFR was 0.78, exactly in the middle of the diagnostic gray zone.
On the other hand, including revascularization in the primary end point was a weakness, Johnson suggested. "After the FAME-2 publication, a lot of ink was spilled in editorials around the world asking the question, 'Should we or should we not focus more on hard outcomes of death and MI?' "
Moreover, the FFR-guided strategy in COMPARE-ACUTE increased the rates of PCI. "If you move to an FFR-guided strategy you need to pay for the extra wires and probably increase the rate of additional PCI by two or threefold," he continued. "Is that something patients are going to want to have, or that health insurance systems are going to want to pay for?"
Leon wanted to know if, based on the evidence so far, cochair Dr Morton J Kern (University of California, Irvine), would recommend FFR-guided multivessel angioplasty for STEMI patients. "The next time you see a multivessel STEMI come in to your institution, will you advise we do FFR of non–infarct-related vessels to be able to guide therapy? Leon asked.
"I would say yes, " Kern replied. "You could defer the intervention to a day or two later . . . but at least you'll know whether to do that rather than bring the patient blindly back to the cath lab, and then do your FFR and find it's negative.
"One caveat," he cautioned, "should be that if you're near the infarct zone, and you have negative FFR, you still have to be little bit cautious about the interpretation. If you're remote from the infarct zone, you can be confident that the FFR value is correct. If it's negative, it's negative."
The trial was supported by Maasstad Cardiovascular Research, which received unconditional grants from Abbott Vascular and St Jude Medical. Smits reports grant support from Abbott Vascular and St Jude Medical during the conduct of the study; grant support and personal fees from Abbott Vascular; and personal fees from St Jude Medical outside the submitted work. Disclosures for the coauthors are listed on the journal website. Køber reports personal fees from Novartis, outside the submitted work.
Heartwire from Medscape © 2017
Cite this: Fewer Re-PCIs After Primary PCI Plus FFR-Guided Intervention: COMPARE-ACUTE - Medscape - Mar 19, 2017.