Medical Device Daily
A new case report published Nov. 30 in Circulation could give cardiologists new insight in describing the association of stent thrombosis with lipid core plaque. Researchers used InfraReDx's (Burlington, Massachusetts) LipiScan Coronary Imaging System to detect acute stent thrombosis with a disrupted lipid core plaque in a patient.
Lipid core plaque is a fatty coronary artery plaque known to complicate stenting and suspected to cause most heart attacks following stenting.
“This isn't a surprising finding,“ James Muller, MD, founder/CEO and chief medical officer of InfraReDX, told Medical Device Daily. “But in the past it has been extremely difficult to identify lipid core plaque in live patients. We've always been able to do it in autopsies but doing it on a living patient was difficult.“
The case followed a 63-year-old patient with hypertension and hyperlipidemia presented to the emergency department with an infero-posterior ST-segment elevation myocardial infarction.
“Our case highlights a possible novel clinical application of a near-infrared spectrosocopy, which may implicate a disrupted lipid rich plaque with exposed tissue factor at the edge of stents as a nidus for stent thrombosis,“ authors of the paper said.
They added that to the best of their knowledge, “this is the first demonstration of acute stent thrombosis associated with residual exposed lipid from the culprit plaque. Future studies are needed to determine the precise pathogenic role of disrupted lipid-rich plaques in stent thrombosis.“
“This case is so important,“ Muller told MDD. “It's important because it shows a lot of what has been blamed on stents, should be blamed on lipid core plaque. But keep in mind this is just one case and one case doesn't change a whole lot, but what it does suggest is that a patient who has a stent over a lipid core plaque has a greater chance of stent thrombosis.“
This proves beneficial to InfraReDx because it can use its LipiScan IVUS system to actually detect lipid core plaque and the device could give an indication of whether or not thromobosis could set in during a stent placement.
“But there will have to be future studies before we [ can make that claim],“ Muller said.
In the meantime, the case draws attention to the firm's device and garners more interest from the medical community.
“We have such a high demand for the device,“ Muller said. “Our initial market is keeping stents safer and we're struggling to keep up with the demand. In the future we're going to satisfy the demand for the device . . . a lot of our energy is going to go into manufacturing it.“
According to the company, the LipiScan IVUS system is able to generate and display the combined chemogram/IVUS analysis immediately upon completion of the single catheter pullback. The LipiScan IVUS system provides physicians with an unparalleled “one-stop“ visual determination of critical coronary features that will assist in care of coronary patients, including identification of lipid-core plaques, degree of stenosis, reference vessel diameter, plaque burden and stent expansion and apposition, the company said.
The LipiScan IVUS system can characterize both the chemical composition and structure of intracoronary plaques and can help guide stent placement, reduce stenting complications, and help determine the most appropriate treatment for patients with coronary artery disease.
In September, InfraReDx reported FDA marketing approval of the LipiScan IVUS Coronary Imaging System. The company said the system is the first to combine intravascular ultrasound (IVUS) with InfraReDx's proprietary near infrared (NIR) spectroscopy to detect lipid-core-containing plaques and assess coronary artery lipid core burden (Medical Device Daily, Sept. 2, 2010). The addition of IVUS imaging enhances the value of LipiScan by providing visualization of the coronary artery lumen, assessment of the structural features of coronary plaque, and identification of proper stent sizing and expansion, the company noted. The LipiScan IVUS system's design provides physicians with a grayscale IVUS image of the coronary artery along with a complete and co-registered chemogram – a map of LCP within the imaged vessel.
The company said that it is looking to snag CE mark approval in the near future.
“We're a little bit different from other companies because we actually received approval in the U.S. first,“ he said. “We went this route because we had strong data backing up our device and we felt gaining FDA approval would not be [difficult].“?
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