The role of inflammation
Of the original 200 patients, 190 completed the full protocol and were available for follow-up.
The primary outcome occurred in only two patients. It turned out that one of the patients had not been adherent with antiplatelet medications.
“Although bleeding occurred in 36 patients, major bleeding occurred in only 1 patient,” the authors report.
The level of platelet reactivity at discharge was 27 ± 42 PRUs. Most patients (91%) met the criteria for low platelet reactivity, while only 0.5% met the criteria for high platelet reactivity. Platelet reactivity was similar, regardless of which P2Y12 inhibitor (ticagrelor or prasugrel) the patients were taking.
In all patients, the level of inflammation was “reduced considerably” over time: After 1 month, the hs-CRP level decreased from 6.1 mg/L (interquartile range [IQR], 2.6-15.9 mg/L) at 24 hours after PCI to 0.6 mg/L (IQR, 0.4-1.2 mg/L; P < .001).
The prevalence of high-inflammation criteria, defined as hs-CRP ≥ 2 mg/L, decreased significantly, from 81.8% at 24 hours after PCI to 11.8% at 1 month (P < .001).
Major bleeding was rare, they report, with a 3-month incidence of 0.5%.
“Inflammation plays a fundamental role in the development and progression of the atherothrombotic process,” the authors explain. A series of factors also trigger “an intense inflammatory response” in the acute phase of MI, which may lead to adverse myocardial remodeling. In the present study, inflammatory levels were rapidly reduced.
They noted several limitations. For example, all enrolled patients were Asian and were at relatively low bleeding and ischemic risk. “Although ticagrelor or prasugrel is effective regardless of ethnicity, clinical data supporting this de-escalation strategy are limited,” they state. Additionally, there was no control group for comparison.
The findings warrant further investigation, they conclude.
Promising but preliminary
Commenting for this news organization, Francesco Costa, MD, PhD, interventional cardiologist and assistant professor, University of Messina, Sicily, Italy, said he thinks it’s “too early for extensive clinical translation of these findings.”
Rather, larger and more extensive randomized trials are “on their way to give more precise estimates regarding the risks and benefits of early aspirin withdrawal in ACS.”
However, added Dr. Costa, who was not involved with the current research, “in this setting, adding colchicine early looks very promising to mitigate potential thrombotic risk without increasing bleeding risk.”
In the meantime, the study “provides novel insights on early aspirin withdrawal and P2Y12 monotherapy in an unselected population, including [those with] STEMI,” said Dr. Costa, also the coauthor of an accompanying editorial. The findings “could be of particular interest for those patients at extremely high bleeding risk or who are truly intolerant to aspirin, a scenario in which options are limited.”
This study was supported by the Cardiovascular Research Center, Seoul, South Korea. Dr. Lee reports no relevant financial relationships. The other authors’ disclosures are listed on the original paper. Dr. Costa has served on an advisory board for AstraZeneca and has received speaker fees from Chiesi Farmaceutici. His coauthor reports no relevant financial relationships.
A version of this article appeared on Medscape.com.