Stent ‘Sealing’ of Nonobstructive Saphenous Vein Graft Plaques Fails to Prevent CV Events
PARIS, France—The first randomized controlled, multicenter trial to test whether the use of stents to “seal” nonobstructive lesions can prevent hard clinical endpoints—specifically in the setting of saphenous vein grafts—has failed to show a benefit for a strategy that was widely hoped to be a good solution for a bad problem.
Josep Rodés-Cabau, MD (Quebec Heart and Lung Institute, Laval, Canada), presented the VELETI II results here today at EuroPCR 2016. The trial, initially designed to enroll 218 patients struggled for 6 years to reach its target, ultimately stopping prematurely with just 125 patients in 2014.
“In a trial that unfortunately we had to stop early, and this prevented us from providing final statements about our primary efficacy endpoint, we can conclude that patients with intermediate saphenous vein graft lesions, sealing such lesions with mainly paclitaxel-eluting stents was safe but . . . failed to prevent events after a median follow-up of 3 years.”
The disappointing results follow the promising VELETI I pilot trial, an imaging study that found sealing intermediate nonobstructive saphenous vein graft (SVG) lesions was safe and appeared on intravascular ultrasound to slow disease progression in the grafts.
Veleti II, was a prospective, multicenter study conducted at 16 sites across Canada designed to show a clinical benefit of stenting SVG lesions in reducing the recurrence of cardiac death, myocardial infarction, or repeat revascularization related to the target SVG lesion over a minimum of 2 years.
To be enrolled in the study, patients who had previously undergone CABG involving at least one SVG had to have a clinical indication for coronary angiography and an SVG lesion with 30-60% diameter stenosis that was not the lesion responsible for the clinical syndrome.
Finding these patients proved extremely hard, Rodés-Cabau told TCTMD. “The problem is that many of these patients, when they have the coronary angiography, a lot of them have either a complete SVG occlusion or nothing at all. In our center, we had to screen about 10 patients to get one patient enrolled.”
Ultimately 65 patients were randomized to medical treatment and 60 to SVG drug-eluting stent implantation. In the stenting group, the mean number of stents per patient was 1.2 and the primary stents used were two brands of now defunct paclitaxel-eluting stents, with 27% of patients receiving a newer, everolimus-eluting stent.
At 30 days there were no differences between groups for the primary composite endpoint or the individual rates of cardiac death, MI, or revascularization. Tracking patients out to 4 years, there continued to be no differences in the rate of MACE or of its individual components, although Rodés-Cabau pointed out that much of this appeared to be due to a catch-up phenomenon in the stent-treated group. At 2 years, he said, the VELETI II results mirrored those of VELETI I, with statistically fewer events in the stent-treated group. By 4 years, however, late restenosis and late stent thrombosis in the stent group, as well as some progression of the disease in other lesions, closed the gap.
Commenting on the study, Augusto D. Pichard, MD (MedStar Washington Hospital Center, Washington, DC, expressed surprise and disappointment, pointing to the positive VELETI I results. VELETI II makes two things very clear, he said. “One, when we put a stent in, we don’t cure the disease, we give the patient a new disease, which we hope is milder. But what we see beautifully here is that eventually, years later, the stents—especially first-generation stents—have problems.”
The second message, he continued, “is that vein graft disease is progressive, no matter what. You fix one lesion, but there is progression in other segments.” It may be that the best strategy for these patients is more aggressive antihyperlipidemia therapy, not interventions.”
To TCTMD, Rodés-Cabau agreed that SVG restenosis is a notoriously difficult disease and that treatment with statins and other drugs likely needs to be “even more aggressive” in these patients.
But he also hinted that the door on interventions may not be fully closed.
“This is probably the only randomized plaque sealing study that has ever been done, because it’s really difficult to identify the lesions that progress and have cardiac events when they are mild to moderate [at the time of treatment],” he said. “I think that maybe a new-generation stent, maybe a bioresorbable stent could have done better, [because] although we had some events related to the progression of the disease in nonstented segments, most of the events in the stent group were related to the stent, mainly late stent thrombosis. So may be a better platform could be evaluated. The problem is, the number of centers you need to reach your sample size is phenomenal.”
Going forward, he said, first-line therapy for SVG stenosis will continue to be optimal antihyperlipidemia treatments, “but there is definitely room for improvement.”
As for stent sealing, “It’s important to see that it is safe and it seems to retard the rate of events within the 2 years following the intervention, when there was literally no events. They started later. But we have to say that the trial was negative and we cannot recommend at least systematically treating these lesions.”
- Rodés-Cabau J. Sealing moderate coronary saphenous vein graft lesions with drug-eluting stents as a new approach to reducing cardiac events. The VELETI II randomized trial. Presented at: EuroPCR 2016. May 18, 2016. Paris, France.
- The study was funded by Boston Scientific.
- Study Supports Role for Plaque Sealing in Moderate SVG Lesions
- Stenting With DES Helps Stave Off Aggressive Disease in SVGs