DENVER – Distal embolic protection using a filter device during primary PCI for acute MI significantly reduced the incidence of the no-reflow phenomenon and serious adverse events in the randomized VAMPIRE 3 trial.
The reason VAMPIRE 3 (Vacuum Aspiration Thrombus Removal) was a positive trial when other studies of distal embolic protection during coronary intervention have failed was that VAMPIRE 3 targeted a high-risk, high-benefit population: the subset of acute MI patients with attenuated, high-risk coronary plaque identified by intravascular ultrasound, Kiyoshi Hibi, MD, explained at the Transcatheter Cardiovascular Therapeutics annual educational meeting.
Also, the filter device used in the trial was easily deployed and problem free, which doesn’t appear to be true of distal protection devices used in some earlier trials.
Discussants agreed with his conclusion, but predicted distal protection during primary PCI for acute coronary syndrome is unlikely to catch on with U.S. interventional cardiologists anytime soon. That’s because, for the most part, they don’t perform advanced imaging in the setting of primary PCI for ACS.
VAMPIRE 3 was a multicenter Japanese study involving 200 patients undergoing primary PCI for acute MI who displayed intravascular ultrasound evidence of attenuated plaque at least 5 mm in length as defined by images showing backward signal attenuation of 180 degrees or more behind a noncalcified plaque. Participants were randomized to placement of the Filtrap distal embolic protection device manufactured by Nipro of Tokyo or to no filter during their procedure, which in all cases entailed the use of a thrombus aspiration catheter.
The primary endpoint was the incidence of the no-reflow phenomenon, an adverse event previously shown by German investigators to be associated with a 66% increase in 5-year mortality (). In VAMPIRE 3, the no-reflow phenomenon occurred in 26.5% of patients randomized to distal protection and 41.7% of those managed conventionally. The secondary endpoint – the corrected TIMI frame count – was 23.0 in the distal protection group, significantly better than the 30.5 in control patients, the cardiologist reported at the meeting, which was sponsored by the Cardiovascular Research Foundation.
The rate of in-hospital adverse events – a composite of death, cardiac arrest, cardiogenic shock, and ischemic stroke adjudicated by an independent committee – was 1% in the distal protection group and significantly higher at 8.3% in conventionally managed controls. All five cases of cardiac arrest/cardiogenic shock occurred in patients who didn’t receive the prophylactic filter, he continued.
In a previous study, Dr. Hibi and his coworkers showed that the incidence of the no-reflow phenomenon in a series of 179 acute MI patients was 18%. More importantly, the incidence was 71% among patients with attenuated plaque of 5 mm or more, compared with 10%-11% among those with less or no attenuated plaque ().
“I am convinced by these results,” discussant, said about VAMPIRE 3, “but the concern is the dependency on imaging. All of these cases were entirely dependent on an imaging diagnosis.
“Certainly in the acute setting, I think Japanese practice is the extreme, with greater than 80% penetration for intravascular imaging, compared to less than 10% in the United States. So to implement your protocol would be difficult unless there was acceptance of the requirement for intravascular imaging,” added Dr. Hill, an interventional cardiologist at King’s College London.
The prevailing philosophy among American cardiologists is that time is heart muscle. The priority is to open the blocked coronary vessel as quickly as possible.
“We don’t use that much advanced imaging,“ agreed, director of cardiovascular research at Saint Luke’s Mid America Heart Institute in Kansas City, Mo.
“It seems like the difference between this trial and previous ones that have not used advanced imaging was the use of intravascular imaging to identify the optimal group of patients that might benefit from this. So I think until that practice changes in the United States, I suspect this is going to get very limited use. I don’t see these devices ramping up quickly for coronary applications,” he predicted.
VAMPIRE 3 was sponsored by Yokohama City University Medical Center and Teikyo University. Dr. Hibi reported serving as a consultant to Nipro and Boston Scientific.
SOURCE: Hibi K. TCT 2017