Self-Expanding and Balloon-Expandable Stent Systems Perform Well in Study of Real-World Peripheral Artery Disease Patients
Two types of stent systems are both effective in treating patients who have severe forms of peripheral artery disease (PAD), according to results of the MOBILITY trial presented today as a late-breaking clinical trial at the SCAI 2012 Scientific Sessions.
The study found patients with complex lesions who were treated with a balloon-expandable stent system, in which a balloon-tipped catheter is inflated to expand and place the stent, or a self-expanding stent system, which is made of flexible material designed to conform to challenging lesions, saw improvement in walking ability, while maintaining low rates of restenosis and major adverse events.
Traditionally, patients with iliac artery disease, a form of PAD that affects the lower extremities, have been excluded from clinical trials if they have highly calcific lesions. However, these patients often are more representative of "real-world" patients treated by interventional cardiologists. The MOBILITY trial was designed to test the effectiveness of a self-expanding stent system and a balloon-expandable stent system in patients with intermittent claudication (IC) or critical limb ischemia (CLI) with even the most complex lesions.
A total of 304 patients with 384 lesions were enrolled in the multi-center trial. Of those, 151 patients were treated with the Absolute Pro Peripheral Self-Expanding Stent System (AP), while 153 were treated with the Omnilink Elite Peripheral Balloon-Expandable Stent System (OLE). A high degree of calcification has been thought to result in failure of endovascular therapy, but that was not seen in the study. After 9 months, the rate of major adverse events was 6.1% for patients treated with AP and 5.4% for patients treated with OLE, significantly below the primary endpoint goal of 19.5% (p<0.0001). Walking ability significantly improved for both sets of patients, and restenosis rates were 8.4% for AP and 9.0% for OLE, even though moderate to severe calcification was noted in 90% of all lesions treated.
"These results demonstrate that balloon-expandable and self-expandable stent systems are effective even in real-world patients. At 9 months, we saw improvements in walking ability, while still maintaining low rates of restenosis and major adverse events," said Michael R. Jaff, DO, FSCAI, medical director of the Vascular Ultrasound Core Laboratory at Massachusetts General Hospital. "The study shows even patients with severe lesions can be successfully treated, helping restore their movement. After 9 months, patients saw improvement in walking distance and speed, as well as ability to climb stairs."
Iliac artery disease is a form of PAD that can progress to the point of impacting walking ability, and can result in chronic pain and even permanent disability. Opening the narrowed arteries can restore blood flow to the legs, resulting in reduced pain and improved walking ability.
Dr. Jaff serves as a non-compensated advisor to Abbott Vascular.