This article is more than 5 years old. Information may no longer be current.
No-reflow phenomenon less likely with distal filter protection in PCI
Use of a filter-based distal protection device reduced the incidence of the no-reflow phenomenon and was associated with fewer in-hospital adverse cardiac events after PCI vs. conventional treatment in patients at high risk for atherothrombotic embolization, according to data from the VAMPIRE 3 study.
The primary endpoint of the incidence of no-reflow phenomenon occurred in 26.5% of the 98 patients assigned distal protection (Filtrap, Nipro), compared with 41.7% of the 96 patients assigned conventional PCI (P = .026). Additionally, patients assigned distal protection had lower corrected TIMI frame count than those assigned conventional PCI (23 vs. 30.5; P = .0003).
Of the 189 patients in whom myocardial blush grade was evaluated at final angiography, 61.5% of patients in the distal protection group and 52.7% in the conventional PCI group had blush grade 3 (P = .223).
Better clinical outcomes
Duration of hospitalization did not differ between the distal protection and conventional PCI groups (12.2 vs. 11.7 days; P = .645). In a post-hoc safety analysis, however, there were fewer in-hospital cardiac adverse events — including cardiac arrest/cardiogenic shock, revascularization requiring defibrillation, cardiopulmonary resuscitation or extracorporeal membrane oxygenation — in the distal protection group vs. the conventional PCI group (5.2% vs. 0%; P = .028). Rates of ischemic stroke and mortality were similar between groups.
The increase in cardiac biomarkers from 6 to 24 hours after PCI were not significantly different between the two groups, nor were the maximum levels of cardiac biomarkers between patients with STEMI in the distal protection group and the patients with STEMI or non-ST segment elevation ACS in the conventional treatment group.
In a subgroup analysis, the distal protection device appeared to be more effective in lesions with angiographically visible thrombus and a baseline TIMI flow grade of 0 to 1. However, there were no significant interactions.
“Distal protection during PCI may facilitate procedural safety without affecting postprocedural myocardial infarct size,” the researchers wrote.
Further considerations
The randomized, open-label VAMPIRE 3 study was conducted at 19 centers in Japan. To qualify for inclusion, all patients had to have ACS with native coronary lesions and attenuated plaque with a longitudinal length of at least 5 mm on IVUS before PCI. No-reflow phenomenon was defined as TIMI flow grade 0, 1 or 2 without mechanical obstruction on the angiogram immediately after stent deployment or after balloon dilatation if the stent could not be implanted.
In an accompanying editorial, Takashi Kubo, MD, PhD, and Takashi Aksaka, MD, PhD, both from the department of cardiovascular medicine at Wakayama Medical University in Japan, discussed some of the limitations of the study.
They noted, for instance, that multiple interacting mechanisms contribute to no-reflow and, consequently, distal protection may not be sufficient for preventing no-reflow.
“In fact, in the VAMPIRE 3 study, no-reflow occurred in 24% even in the distal protection group,” Kubo and Aksaka wrote.
They also cited other problems with the distal protection device, including the fact that it is not useful and can be problematic in patients with bifurcation lesions or tortuous or calcified vessels with tight lesions, among other issues.
Kubo and Aksaka also pointed out that this study, compared with other studies, combined the use of the distal protection device and aspiration catheter. As a result, the decrease in no-reflow could be attributed to the combination of distal protection and aspiration vs. distal protection alone.
“The VAMPIRE 3 study demonstrated that distal protection during PCI improved angiographic and clinical outcome immediately after the procedure in patients at high risk for atherothrombotic embolization. Further investigation is needed to evaluate the long-term effects of distal protection in those selected patients,” they wrote. – by Melissa Foster
Disclosures: The study was partially supported by a grant from Nipro, Boston Scientific and Japan Lifeline. Please see the study for all authors’ relevant financial disclosures. Akasaka reports he has received research funds from Nipro and Boston Scientific. Kubo reports no relevant financial disclosures.