Myocardial infarction more common after carotid endarterectomy than stenting

The CREST (Carotid Revascularization Endarterectomy Versus Stenting Trial) found a higher risk of myocardial infarction after carotid endarterectomy while the risk of stroke was higher after carotid artery stenting. Blackshear JL et al (Circulation. 2011;123:2571-2578), in sub group analysis evaluated this aspect further. Myocardial infarction was defined as biomarker elevation plus either chest pain or evidence of myocardial ischemia on the electrocardiogram. Isolated biomarker elevation without chest pain or ECG evidence of ischemia was also evaluated separately. Of the 2500 odd patients myocardial infarction occurred in 14 of the carotid artery stenting group and 28 of the carotid endarterectomy group (p=0.032). Eight patients in the carotid artery stenting group and 12 patients in the carotid endarterectomy group had isolated biomarker elevation without chest pain or ECG evidence of myocardial infarction (p=0.36). The median biomarker elevation was 14 times the upper limit of normal in this group while it was 40 times the upper limit of normal in the myocardial infarction group. Mortality at four years was higher in those with myocardial infarction than in those with isolated biomarker elevation. Both myocardial infarction and isolated biomarker elevation were independently associated with increased risk of mortality after adjustment for baseline risk factors.