Patients with ACS who underwent coronary angiography and were assigned prasugrel had lower rates of CV death, MI and stroke compared with patients who underwent angiography and were assigned clopidogrel, according to a subgroup analysis of the TRILOGY ACS trial.
The observed benefit with prasugrel (Effient, Daiichi Sankyo/Eli Lilly) was not observed in patients who did not undergo angiography, Stephen Wiviott, MD, of the cardiovascular division of Brigham and Women’s Hospital, and colleagues reported.
“These data may have implications for patient care, since the patients who seem to benefit most from intensified anti-platelet treatment are those with confirmed coronary artery disease,” Wiviott said in a press release. “However, these data would need to be verified in another study before making such a recommendation.”
For the subgroup analysis, Wiviott and colleagues assessed outcomes from the overall TRILOGY ACS trial based on whether patients had angiography before study treatment was assigned.
The randomized, controlled TRILOGY ACS trial was conducted at more than 800 international sites. The primary analysis included 7,243 patients aged younger than 75 years with non-ST–elevation ACS who were selected for revascularization and randomly assigned prasugrel (30-mg loading dose and 10-mg/day maintenance dose) or clopidogrel (300-mg loading dose and 75 mg/day maintenance dose). Of those, 43% underwent angiography at baseline.
The primary composite endpoint was CV death, MI or stroke at 30 months. Secondary endpoints included CV death, MI and stroke assessed individually.
Patients who underwent angiography had a lower rate of the primary composite endpoint compared with those who did not undergo angiography (12.8% vs. 16.5%; adjusted HR=0.63; 95% CI, 0.53-0.75). Among those who had angiography, prasugrel use was associated with a lower rate of the primary composite endpoint vs. clopidogrel use (10.7% vs. 14.9%; HR=0.77; 95% CI, 0.61-0.98). However, among those who did not undergo angiography, there was no difference in the primary composite endpoint between the prasugrel and clopidogrel groups (16.3% vs. 16.7%; HR=1.01; 95% CI, 0.84-1.2).
Rates of TIMI major bleeding and GUSTO severe bleeding were rare. Rates were slightly higher in the prasugrel group, but not significantly different between treatment groups in either angiography cohort, according to the study abstract. Subsequent revascularization was also rare, although “patients who did not have angiography were more likely to have recurrent [CV] events than patients who did have angiography before treatment,” the researchers wrote.
Deepak L. Bhatt
“This study supports the potential benefit of strong antiplatelet medications [in this patient population] … and reaffirms the value of cardiac catheterization in the management and triage of patients with acute chest pain,” Deepak L. Bhatt, MD, MPH, TRILOGY ACS investigator and Cardiology Today’s Intervention Chief Medical Editor, stated in the release.
Angiography linked to better outcomes
In a related editorial, Rajesh V. Swaminathan, MD, and Dmitriy N. Feldman, MD, both from New York Presbyterian Hospital, Weill Cornell Medical College, Greenberg Division of Cardiology, N.Y., said the key question raised by the study is why angiography resulted in better clinical outcomes.
“The reason — and perhaps the most important lesson from this analysis — is that patient selection is crucial,” they wrote. “Patients enrolled without angiography were more likely to be older, female, have lower body weight, worse renal function, higher Global Registry of Acute Coronary Events scores, and present with unstable angina (as opposed to non-ST segment elevation myocardial infarction). Therefore, patients with more comorbidities were more likely to be treated without angiography.”
For more information:
Swaminathan RV. Lancet. 2013;382:580-582.
Wiviott SD. Lancet. 2013;382:605-613.
Disclosure: The study was funded by Daiichi Sankyo and Eli Lilly. See the full study for a list of the researchers’ disclosures. Feldman has served as a consultant or speaker for Abbott Vascular, Bristol-Myers Squibb, Daiichi Sankyo, Eli Lilly and Pfizer. Swaminathan reports no relevant financial disclosures.