DALLAS, TX — Using fractional flow reserve (FFR) during diagnostic catheterization led to a change in treatment strategy in almost half of the patients in a large French database but, importantly, did not radically alter the proportion of patients undergoing revascularization or being managed medically.
Dr Eric Van Belle (University Hospital, Lille, France) presented the registry results earlier this week at the American Heart Association 2013 Scientific Sessions ; the study was published simultaneously in Circulation.
As Van Belle explained to heartwire , the study offers a new layer to the understanding of FFR's role in day-to-day practice. In the large pivotal trials of FFR, including FAME , FAME 2 , and DEFER , FFR was typically applied after the decision to proceed with PCI had already been made. The FFR results were then used to determine when a PCI procedure could be deferred or proceed as planned. In the French registry, FFR was performed "as part of the diagnostic angiogram and so earlier than was done previously. And what we show here is that if you use FFR at this stage, you will reclassify almost 50% of the patients, but the proportion of patients [who received PCI, bypass surgery, or medical therapy] will not change, or not much."
The Registre Français de la FFR included 1075 consecutive patients who underwent diagnostic angiography plus FFR at one of 20 centers. Investigators were asked to set out their treatment plan following the angiography but before the FFR. Prior to FFR, physicians planned to treat 55% of patients with medical therapy, 38% with PCI, and 7% with coronary artery bypass. Following FFR, those numbers shifted slightly: 58% were treated medically, 32% with PCI, and 10% with CABG.
Of note, however, on an individual level, a full 43% of patients had their treatment plan changed on the basis of the FFR results. The treatment plan was changed for 33% of patients originally destined for medical therapy, for 56% of patients who were initially heading to PCI, and for 51% in whom the original intent was CABG.
On the basis of FAME and DEFER, said Van Belle, "most cardiologists have in mind that if you do FFR, you will prevent a lot of patients from undergoing revascularization, and that wasn't the case in our study. The numbers were slightly less, but the patients are not the same patients."
Another interesting finding that emerged in the database was that certain vessels were more likely to be linked with a change in treatment plan after FFR. "What we saw was that lesions on the LAD and lesions that are proximal lesions play a greater role in the ischemia, and that is what the FFR analysis demonstrates. With a LAD or proximal lesion, you are more likely to undergo revascularization. If it is not a LAD or it is a distal lesion, it was more likely that the management will switch to a less aggressive treatment."
Importantly, one-year major cardiac events were similar between patients whose treatment had proceeded according to the original plan (confirmed by FFR) and in patients whose management plan had changed on the basis of FFR results. Moreover, 93% of patients in both groups were asymptomatic at one year. Outcomes were worse in the very small proportion of patients in whom the operator had ignored the FFR findings and proceeded with his or her original plan.
"We have to keep in mind that the investigators were very compliant with FFR, so when FFR suggested something, most of the time they were doing it. In a minority of cases , the outcomes were very bad, and patients didn't do well, but still we don't know exactly why the investigators decided to not follow the FFR measurements. So at this stage, it is just a signal."
Van Belle disclosed being a consultant from St Jude Medical and receiving speaker's fees from Volcano.
Heartwire from Medscape © 2013 Medscape, LLC
Cite this: FFR 'Reclassifies' 43% of Patients, Without Cutting PCI Rates - Medscape - Nov 22, 2013.