Key result
Aspirin resistance in patients with suspected acute coronary syndrome was associated with a significantly increased risk of adverse cardiac events over 6 months (HR 10.0; 95% CI 4.6-22.0).
Why the study?
Does aspirin resistance determined by a bed-side test predict adverse cardiac events in patients presenting with suspected acute coronary syndrome?
Cohort (n=314)
Blinded to test results
Does aspirin resistance determined by a bed-side test predict adverse cardiac events in patients presenting with suspected acute coronary syndrome?
Hazard Ratio: 10 (95% CI 4.6–22)
Absolute Event Rate: 10% vs 8.8%
p-value: p=0.91
Aspirin resistance identified by a bedside test in patients presenting with suspected ACS is strongly associated with an increased risk of major adverse cardiac events at 6 months.
Should not yet change practice in suspected ACS; leaves open whether bedside testing warrants prospective validation.
BACKGROUND: Coronary patients resistant to aspirin may have increased risk for ischemic events. Little data were available for patients presenting acutely with chest pain. METHODS AND RESULTS: We used the VerifyNow Aspirin to determine aspirin responsiveness of 314 patients regularly taking aspirin 75-300 mg daily for >or=4 weeks who presented with suspected acute coronary syndrome in Emergency Department. Aspirin resistance was defined as an aspirin reaction unit (ARU) >or=550, and the clinical team was blinded to the ARU reading. The pre-specified study endpoints were the diagnosis of acute myocardial infarction (AMI) for the index admission and major adverse cardiac events including cardiovascular death or recurrent acute coronary syndrome requiring hospitalization within 6 months. Aspirin resistance was noted in 30 (9.6%) patients. There was no difference in the diagnosis of AMI for the index presentation (3/30, 10% vs. 25/284, 8.8%, P = 0.91). Among the 312 hospital survivors, aspirin resistant patients had increased adverse events over 6 months with an overall hazard ratio of 10.0 [95% confidence interval (CI) 4.6-22.0]. After adjusted for elevated Troponin-T, the only confounder in the model, the hazard ratio was 11.1 (95% CI 4.7-26.0). Results were similar in patients treated only medically without revascularization (adjusted hazard ratio 12.1, 95% CI 4.7-26.4). The increased events were observed both from discharge to 30 days and from 30 days to 6 months. CONCLUSION: Aspirin resistance occurs in approximately 10% of patients presenting with suspected acute coronary syndrome and is associated with adverse cardiac events.
No takes yet. Share an insight, caveat, or question.
Chu et al. (2010) conducted a cohort in Suspected acute coronary syndrome (n=314). Aspirin resistance (ARU ≥550) vs. Aspirin responsive (ARU <550) was evaluated on Diagnosis of acute myocardial infarction (AMI) for the index admission and major adverse cardiac events including cardiovascular death or recurrent acute coronary syndrome requiring hospitalization within 6 months (HR 10.0, 95% CI 4.6-22.0, p=0.91). Aspirin resistance in patients with suspected acute coronary syndrome was associated with a significantly increased risk of adverse cardiac events over 6 months (HR 10.0; 95% CI 4.6-22.0).
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: