Spontaneous MI common after medically managed NSTEACS
Researchers have determined that spontaneous MI after medically managed non–ST-segment elevation ACS is common.
The researchers analyzed 9,294 patients from TRILOGY ACS for spontaneous MI and developed a prediction model for spontaneous MI in patients with non-STEMI or unstable angina who do not undergo revascularization.
All patients had been randomly assigned aspirin plus prasugrel (Effient, Eli Lilly/Daiichi Sankyo) or aspirin plus clopidogrel after non–ST-segment elevation ACS (NSTEACS) and were followed for 30 months.
High event rate
In this study population, there were 695 spontaneous MIs (94% of 737 adjudicated MI events) during a median follow-up of 17 months, for an event rate of 10.7% during 30 months.
Lopes and colleagues found five particularly strong predictors of spontaneous MI after medically managed NSTEACS (P < .0001 for all): age per 5-year increase (HR = 1.19, 95% CI, 1.14-1.23), non-STEMI as opposed to unstable angina (HR = 2.46; 95% CI, 1.98-3.05), diabetes (HR = 1.51; 95% CI, 1.29-1.76), no pre-randomization angiography (HR = 1.52; 95% CI, 1.28-1.8) and baseline creatinine per 1-mg/dL increase for values of 0.85 mg/dL or more (HR = 1.89; 95% CI, 1.42-2.5).
When they developed a model based on 17 variables, it had a C-index of 0.732 (standard error = 0.011) and good calibration, particularly for patients at low to moderate risk for spontaneous MI.
“By providing time-dependent risk estimates over an extended period of follow-up after medical management for an NSTEACS event, this tool may have important clinical applications, informing patients and clinicians of the risk of spontaneous MI,” Lopes, from Duke Clinical Research Institute, Duke University School of Medicine, and colleagues wrote. “This enhanced awareness of MI risk could reinforce the importance of provision of, and adherence to, evidence-based secondary prevention medications and lifestyle changes.”
In a related editorial, Gennaro Sardella, MD, and Massimo Mancone, MD, PhD, both from the department of cardiovascular, respiratory, nephrology, anesthesiology and geriatric sciences, “Sapienza” University of Rome, wrote, “This predictive model could play a different important role in different regions: Where an invasive coronary evaluation is not widespread and easily achievable, it can confirm the necessity of a coronary angiography and give patients who are not planned for angiography and revascularization a ‘second chance’; in the countries with a high rate of coronary invasive evaluation, it will be very useful to identify ACS patients who are not suitable for revascularization and are at high risk for a new myocardial event to optimize secondary prevention.” – by Erik Swain
Disclosure: The TRILOGY-ACS study was sponsored by Daiichi Sankyo and Eli Lilly. Lopes reports receiving research grants and consulting fees from Bristol-Myers Squibb, GlaxoSmithKline, Merck and Portola, and consulting for Bayer, Boehringer Ingelheim and Pfizer. Please see the full study for a list of the other researchers’ relevant financial disclosures. Sardella and Mancone report no relevant financial disclosures.