One in 14 patients who underwent PCI did not receive aspirin 24 hours before the procedure, according to a poster scheduled to be presented March 11 at the American College of Cardiology (ACC) scientific session in San Francisco. Patients who did not receive aspirin had higher in-hospital mortality and stroke rates.
The guidelines from the ACC and American Heart Association recommend that patients already on daily aspirin therapy receive 81 mg to 325 mg before PCI. Those patients not on aspirin therapy should be given 325 mg aspirin before PCI to reduce the risk of cardiac events.
To assess the incidence of PCI performed without prior aspirin administration, Mohamad Kenaan, MD, a cardiovascular medicine fellow with University of Michigan Health System in Ann Arbor, and colleagues used registry data from the Blue Cross Blue Shield of Michigan Cardiovascular Consortium PCI Quality Improvement Initiative. They identified 65,157 patients from 42 hospitals in Michigan enrolled in the program between January 2010 and December 2011.
Of those patients, 7.1 percent did not receive aspirin 24 hours before PCI. Compared with patients who did receive aspirin, they were more likely to have gastrointestinal bleeding or present in cardiogenic shock.
The unadjusted in-hospital mortality rate was 3.9 percent in the non-recipient group vs. 1.2 percent in the aspirin group. A propensity-matched analysis found that the lack of aspirin 24 hours before PCI was associated with a higher mortality rate and a higher stroke rate (adjusted rates of 3.9 percent vs. 2.8 percent, and 0.5 percent vs. 0.1 percent, respectively). There was no difference between aspirin recipients and non-recipients in bleeding, the need for transfusions or contrast-induced kidney damage.
“Our study is not designed to confirm a direct causal effect of aspirin use on PCI outcomes, but [rather] to examine any association with worse outcomes,” Kenaan said in a statement. “Moreover, it highlights an unexpectedly significant number of patients undergoing PCI without receiving aspirin, despite the lack of a documented contraindication in the majority of cases—even in institutions that are active participants in an ongoing quality improvement initiative.”
The registry does not include post-discharge data. Researches will conduct more analyses to assess hospital length of stay and bleeding.