Study finds no benefit of routine orbital atherectomy in cardiac stenting

Routine use of an orbital atherectomy device to remove calcium from severely blocked coronary arteries before patients undergo cardiac stenting procedures does not improve outcomes, a Mount Sinai-led study has found.

The results of the ECLIPSE study were announced during a late-breaking trial presentation at the Transcatheter Cardiovascular Therapeutics Annual Meeting on Tuesday, October 29. This is the first large-scale study to study this specific device in severely calcified lesions, and the results support reserving its use for extreme cases.

Operators across the United States currently have different thresholds for using atherectomy or other advanced lesion preparation techniques when treating severely calcified lesions. While these devices are essential to treat the most extreme cases prior to implanting a stent, it was unknown before this study whether their routine upfront use in patients with severely calcified lesions that are less than extreme would safely improve outcomes after drug-eluting stent implantation."

Gregg W. Stone, MD, study chair, Director of Academic Affairs for the Mount Sinai Health System and Professor of Medicine (Cardiology), and Population Health Science and Policy, at the Icahn School of Medicine at Mount Sinai

"The large-scale, multicenter ECLIPSE trial has shown that the routine use of orbital atherectomy did not lead to greater stent expansion or improve one-year patient outcomes compared to routine balloon angioplasty prior to stenting. Therefore, the use of orbital atherectomy may be reserved for the most extreme cases for which the operator does not believe that balloon angioplasty would be likely to safely cross or pre-dilate the calcified lesion."

Patients with coronary artery disease-;plaque buildup inside the arteries that leads to chest pain, shortness of breath, and heart attack-;often undergo percutaneous coronary intervention (PCI), a non-surgical procedure in which interventional cardiologists use a catheter to place stents in the blocked coronary arteries to restore blood flow. Cardiologists first put a balloon through the artery to make the opening big enough for the stent to fit in permanently.

Heavily calcified blockages are more challenging to open with balloon angioplasty, which may lead to stent complications including heart attacks. One option cardiologists use to avoid this in severely calcified lesions is orbital atherectomy-;a device from Abbott Vascular, in Santa Clara, California, approved by the Food and Drug Administration for this purpose that fractures and sands the calcium, allowing balloons and stents to better expand. Atherectomy devices (orbital or other types) are used in more than 10,000 patients per year undergoing PCI in the United States, and in up to 10 percent of PCI cases at some hospitals.

Investigators launched the ECLIPSE study to figure out whether routinely using the orbital atherectomy device in severely calcified lesions that might be adequately expanded by balloons only would allow the stent to better expand and improve clinical outcomes. They enrolled 2,005 cardiac patients with 2,492 lesions at 104 sites across the United States and randomized roughly half to receive orbital atherectomy and half to balloon angioplasty; both groups then underwent PCI with drug-eluting stents. The primary endpoints were stent expansion and one-year clinical outcomes.

Researchers used optical coherence tomography (OCT) imaging to assess the stent area in both groups. At the end of the procedure, the stent area was not greater in the atherectomy group compared with the balloon angioplasty group. The minimal stent area at the site of maximal calcification was 7.67 ± 2.27 mm² in the orbital atherectomy group and 7.42 ± 2.54 mm² in the balloon angioplasty group, a difference that was not statistically significant. Additionally, orbital atherectomy did not reduce the one-year rate of target vessel failure, which is a combination of cardiac death or myocardial infarction or repeat intervention attributable to the treated vessel. In the orbital atherectomy group, 114 patients (11.6 percent) had target vessel failure, compared with 95 patients in the balloon angioplasty group (9.8 percent), also a non-significant difference.

Among secondary outcomes, there were more cardiac deaths at 30 days after PCI in the orbital atherectomy group compared with the balloon group (eight versus zero). Cardiac death within one year occurred in 30 patients (4.0 percent) compared to 26 patient (2.7 percent) in the balloon angioplasty group, a non-significant difference. There were no significant differences in other major safety outcomes, including vessel perforation or heart attack.

"In this trial, the atherectomy procedure was longer and required use of more guide wires and other interventional devices, more contrast, and more radiation compared with procedures using balloons only for lesion preparation. Given the absence of clear benefit, these results support reserving use of orbital atherectomy for the most extreme cases that the operator does not believe would be safely crossed or dilated with a balloon. Such cases were not included in the present trial," added Dr. Stone "It is important to note that the event rates were lower in both the balloon and atherectomy groups of patients in whom OCT was used to guide the procedure, consistent with the results from other studies that have shown that intravascular imaging use improves PCI outcomes in complex lesions. Finally, these results apply to lesion preparation with orbital atherectomy only. Whether the routine use of other advanced lesion preparation techniques in severely calcified lesions, including rotational atherectomy or intravascular lithotripsy, would improve stent expansion and clinical outcomes after PCI is unknown."

This study was funded by Abbott Vascular.