Optimization of fractional circulate reserve (FFR) after angiographically profitable percutaneous coronary intervention (PCI) didn’t impression scientific outcomes however considerably diminished the proportion of sufferers leaving the cath lab with an FFR of 0.80 or much less in a single-center randomized trial.
After standard-of-care PCI, solely 32% of sufferers achieved a post-PCI FFR of at the least 0.90, which has been proven to be related to a decrease threat for repeat PCI and main antagonistic cardiovascular occasions.
Maybe extra regarding, 29% of sufferers had a closing FFR at or beneath the guideline-recommended revascularization threshold of 0.80, mentioned examine creator Damien Collison, MD, Golden Jubilee Nationwide Hospital and College of Glasgow, United Kingdom.
The TARGET-FFR trial concerned 260 sufferers with coronary artery disease, together with stable angina and non-ST-segment myocardial infarction, who had been randomly assigned after angiographically profitable PCI to blinded post-PCI coronary physiology evaluation or to a physiology-guided incremental optimization technique (PIOS).
If a affected person within the PIOS group had a suboptimal FFR lower than 0.90, the physiology outcomes had been disclosed to the operator and additional optimization suggested primarily based on the outcomes of FFR pullback evaluation.
Particularly, if the FFR pullback indicated diffuse illness sample with no focal step-ups and the hyperemic trans-stent gradient (HTG) was lower than 0.05 models, the case was deemed full, Collison mentioned.
If the HTG was at the least 0.05, postdilatation with a bigger noncompliant balloon to 18 atm was suggested, and if a focal step-up of at the least 0.05 was recognized exterior the stented phase, a further stent was really useful. Lastly, FFR pullback was repeated and if both of the 2 earlier standards had been current, operators might carry out additional postdilatation or deploy one further stent.
Based mostly on FFR pullback evaluation, a substrate for additional optimization was current in 60 of 131 (46%) PIOS sufferers. Operators felt it acceptable to carry out further post-dilatation and/or stenting in 66% of those sufferers.
Amongst these 40 instances, each FFR and coronary circulate reserve (CFR) elevated from technique of 0.76 to 0.82 (P <.001) and from 3.0 to 4.0 (P = .02), respectively, Collison reported in a late-breaking session on the digital Transcatheter Cardiovascular Therapeutics (TCT) 2020.
The proportion of sufferers with a closing FFR of at the least 0.90 — the examine’s major finish level — elevated from 28.1% to 38.1% with PIOS, however this didn’t obtain statistical significance primarily based on a hypothesized 20% between-group distinction (P = .09).
The PIOS technique, nevertheless, did considerably scale back the proportion of sufferers with a closing FFR of 0.80 or much less (18.6% vs 29.8%; P = .045).
Not unexpectedly, this got here at the price of considerably longer process (94 vs 67 minutes) and fluoroscopy (23 vs 16 minutes) occasions, in addition to larger radiation (921 vs 686 mGy) and adenosine (93 vs 62 mg) doses, Collison mentioned.
Procedural problems had been comparable in every group (2.5 vs 9.5 with out PIOS; P =.14).
At a median of 105 days, there was no distinction within the change within the Seattle Angina Questionaire-7 abstract rating or its particular person domains between the 2 teams.
One goal vessel failure and one cardiac loss of life occurred within the PIOS group, in contrast with no such occasions amongst management topics over a median of 1.7 years.
In an evaluation stratified by goal vessel, there was no important distinction in pre-PCI FFR or CFR. However imply post-PCI FFR was significantly decrease within the left anterior descending (LAD) artery than within the left circumflex or proper coronary arteries (0.80 vs 0.92 vs 0.91; P <.001), which helps earlier registry knowledge that an LAD goal lesion is a constant predictor of suboptimal post-PCI FFR outcomes, Collison mentioned.
Discussant Bernard De Bruyne, MD, PhD, OLV Clinic, Aalst, Belgium, mentioned the examine lacked energy to show PIOS might enhance affected person outcomes or obtain larger FFR values however highlights the necessity for various FFR cutoffs in several vessels.
“The LAD is mostly a completely different animal by way of post-PCI FFR and, really even pre-PCI FFR,” and may have an FFR already within the area of 0.8 with out stenosis to begin with, “which isn’t the case in the appropriate coronary artery,” he mentioned. “So most likely sooner or later we must conceive research focusing on completely different thresholds, particularly the appropriate and the LAD.”
Collison noticed that, maybe confusingly, registry knowledge has already proposed that the LAD ought to have both the next or decrease optimum threshold than different vessels. “Between you and I and the world, if you wish to obtain FFRs of 0.90, you need to change your observe to only stent proper coronaries and left circumflex,” he quipped.
Discussant Allen Jeremias, MD, St. Francis Hospital, Roslyn, New York, mentioned TARGET-FFR is an eye-opening examine.
“I am slightly bit shocked that residual ischemia is even higher than we noticed in DEFINE-PCI and actually solely a 3rd of those have an optimum end result with an FFR of greater than 0.90 with angiographic steerage alone,” he mentioned. “So I feel it actually reinforces the significance of doing physiology earlier than and after to information PCI to get to raised outcomes.”
The outcomes additionally underline the significance of FFR pullback evaluation, which is underutilized, Jeremias instructed. “We go away plenty of info on the desk.”
In a TCT wrap-up video, Roxana Mehran, MD, Icahn Faculty of Medication at Mount Sinai, New York Metropolis, mentioned she additionally was shocked that so few sufferers met the 0.90 standards however expressed some hesitancy in regards to the FFR thresholds post-PCI.
“We simply offered Xience data with such a low occasion charge and, consider me, they don’t seem to be doing FFR on the finish of each a type of procedures,” she mentioned. “So if that is the case, then we must always have had much more occasions. So I do not assume that an FFR of 0.80 really holds true for scientific occasions postprocedure because it does preprocedure of whether or not you need to go forward to do one thing or not. And I feel you are able to do hurt if you happen to simply hold going.”
The examine was sponsored by the NHS Nationwide Ready Instances Centre Board. Collison reported consulting charges/honoraria from Abbott Medical and MedAlliance.
Transcatheter Cardiovascular Therapeutics (TCT) 2020. Introduced October 16, 2020.