Lipid-rich plaque in non-culprit lesions has long been associated with subsequent cardiac events. Unlike culprit lesions, known to be the cause of AMI, non-culprit lesions including those with a core of lipid-rich plaque are often left untreated during an intervention. The fact that these lesions may lead to further injury has prompted several studies to determine whether these lesions should be treated during the initial PCI.
The Danger of Lipid-rich Plaque
Recent results from ad hoc research by the Massachusetts General Hospital OCT has found that the presence of lipid-rich plaques in non-culprit areas of target vessels can double the risk of subsequent MACE (major adverse cardiac events) in patients who have had a PCI or other intervention. This four-year retrospective study of 1,474 patients found that there were 74 instances of MACE in these patients. This amounted to a rate of 7.1 percent, including 66 symptomatic ischemic revascularizations, five cardiac deaths, and 21 AMIs. It was also observed that the events stemming from the targeted or culprit lesion occurred at only a rate of 2.6 percent, while nonculprit events happened at a rate of 4.3 percent. At 48 months, the nonculprit MACE rate was higher in a full one-third of patients diagnosed with lipid-rich plaque than in those without the presence of this plaque.
Should These Findings Influence PCI Targets?
Does this study indicate that cardiologist should target nonculprit lesions or should patients be monitored as simply having an increased risk factor?
“I am against the local approach,” stated Ik-Kyung Jang, MD, Ph.D., senior author of the research. According to Dr. Jang, the presence of lipid-rich plaque doesn’t indicate that that the nonculprit lesion has to be treated. There is a need, however, to focus on aggressive prevention. Treatments such as cholesterol-lowering therapy, diet, and follow-up are precisely indicated.
Another important finding was that 20 percent of the patients found to have lipid-rich nonculprit lesions and subsequent MACE were not taking statins or had an interruption of statin use for longer than one year, which many believe is an independent predictor of MACE.
Use of Advanced Imaging Techniques
Only 15 percent of all PCIs are performed while using intravascular imaging. Currently, this is the only way to determine the presence of lesions containing a core of lipid-rich plaque. This information begs the simple question, do we have enough information to inform patient care at this level?
Email: ken@prime-core.com
