Original title: Prognostic impact of clopidogrel pretreatment in patients with acute coronary syndrome managed invasively. Reference: Almendro-Delia M et al. Am J Cardiol. 2015; Epub ahead of print.
This study analyzed the ARIAM data including 9621 AMI patients diagnosed with coronary angiography receiving clopidogrel in 49 center between 2002 and 2012. Most patients had STEMI (63%), and most of the overall cohort received clopidogrel pretreatment (70%), defined as any dose given at the time of first medical contact prior to angiography or PCI.
Most of cases were STEMI patients (63%) and most patients had received clopidogrel pretreatment (70%) defined as any dose administered at the time of first medical contact and prior to angiography or PCI. In the overall cohort, pretreatment was associated to a lower rate of MACE (cardiovascular death, reinfarction and stroke) and stent thrombosis.
After a multivariable analysis adjusted according to the different characteristics, pretreatment was associated to better clinical outcomes at the cost of higher minor bleeding rates in STEMI patients, not in the rest of the ACS spectrum.
Combining ischemic and bleeding endpoints, a significant reduction of net adverse clinical events was observed in STEMI patients (OR 0.56; CI 95% 0.44-0.70) but not in NSTE-ACS patients (OR 0.91; CI 95% 0.64-1.29). These results were confirmed after propensity matched analysis.
In the subgroup analysis, an interaction was observed (p=0.048) suggesting that the shorter the pretreatment, the lower the bleeding risk.
Conclusion
Clopidogrel pretreatment improves inhospital outcomes only in patients undergoing ST elevation AMI. This strategy reduced bleeding risk and had a net clinical benefit in this subgroup of patients.
Editorial Comment
Data supporting pretreatment in STEMI patients are somewhat weak and based on ad hoc results. However, taking into account the infarction physiopathology, the high thrombus burden and the delay in the onset of action of this drug, pretreatment in a habitual practice in PCI, and this supports the guideline recommendation to give clopidogrel at first medical contact. This recommendation should be studied for the rest of AC syndromes.
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