Higher Fibroatheroma Prevalence, Lower Healed Plaques Seen in Those with Recurrent ACS

Patients on the extreme end of the coronary artery disease spectrum, like those with recurring acute coronary syndrome (ACS), have unique phenotypes and plaque healing compared to patients with longer-term clinical stability, a new study suggests.

The observations, single-center study included 105 patients with recurrent ACS (at least 3 myocardial infarctions [MI] or at least 4 ACS with at least 1 MI); patients with a single unheralded acute MI followed by 3 years of clinical stability (sAMI); and longstanding stable angina. Patients all underwent optical coherence tomography, with data analyzed between January and August 2018. Coronary plaque features and healed coronary plaque prevalence in nonculprit segments comprised the primary study outcome measures. Median time of clinical stability was 9 years in the long-standing stable angina group and 8 years in the sAMI group.

Different Phenotypes

The study results suggested that patients with recurrent ACS possess a “distinct atherosclerotic phenotype” from those with long-standing stable angina. Patients in the sAMI and recurrent ACS groups had similar lipid-rich plaque prevalence (which was higher than those with angina) and thin-cap fibroatheroma compared to those with angina. Spotty calcifications, according to the authors, were observed more frequently in patients with recurrent ACS than in those with angina and those in the sAMI group (P=0.04). In addition, those with recurring ACS had a lower prevalence of healed coronary plaques than patients with longstanding angina and those in the sAMI group (P=0.01).

“Patients with ACS and those with sAMI showed a similar prevalence of lipid-rich plaque and thin-cap fibroatheroma, as well as similar angiographic disease burden and progression, which were significantly lower in patients with longstanding stable angina pectoris,” the researchers wrote in their conclusion. “Healed coronary plaques, a signature of prior plaque destabilization contained by reparative mechanisms, which are characterized by a multilayered, onion-like appearance at optical coherence tomography imaging, were rarely observed in patients with recurrent acute coronary syndromes, whereas their prevalence was significantly higher in patients with longstanding stable angina pectories and sAMI.”

The researchers continued in their conclusion that “taken together, these findings suggest that although atherosclerotic disease phenotype and burden are important predisposing factors for acute coronary disease, other factors, including plaque healing, may lead the natural history of a patient toward either recurrence of acute events or long-term clinical stability.”

Eric Raible is editor of the Cardiology section of DocWire News and has more than a decade’s worth of experience in covering and publishing in the cardiology space. Eric has previously served as a founding editor of CardioSource WorldNews, and is a former staff writer and editor of Cardiology Today.