NEW YORK (Reuters Health) – Analysis of data from the CREST study of carotid endarterectomy versus carotid stenting, shows that rates of elevated cardiac enzymes and of MI are higher after endarterectomy. Furthermore, both occurrences are independently associated with increased mortality subsequently, according to a report in Circulation for June 7.
It has been suggested, note Dr. Thomas G. Brott, with the Mayo Clinic in Jacksonville, Florida and colleagues, that, compared to stroke, the occurrence of MI is relatively unimportant in terms of overall health for patients requiring carotid revascularization. On the other hand, an increase in cardiac enzymes during various procedures has been linked to poorer outcomes.
They therefore to assessed the impact of MI among patients undergoing carotid artery stenting (CAS) or carotid endarterectomy (CEA), in a post hoc analysis of CREST results.
In CREST, MI was defined as elevated cardiac biomarkers plus either chest pain or indications of ischemia on ECG. “An additional category of biomarker elevation with neither chest pain nor ECG abnormality was prespecified (biomarker+ only),” the authors explain.
Twice as many MIs occurred in patients undergoing CEA as CAS (28 vs 14; p=0.032), according to the report. Additionally, the corresponding numbers of biomarker+ cases were 12 vs 8 (p=0.36).
“Compared with patients without biomarker elevation, mortality was higher over 4 years for those with MI (hazard ratio, 3.40) or biomarker+ only (hazard ratio, 3.57),” Dr. Brott and colleagues found.
After adjustment, both MI and biomarker+ only were shown to be independent risk factors for increased mortality – “an important consideration in choosing the mode of carotid revascularization or medical therapy,” the researchers conclude.
The latter point is amplified in an editorial by Dr. Scott Kinlay, with the VA Boston Healthcare System in Roxbury, Massachusetts. “Contemporary optimal medical therapy directed against atherosclerosis and platelet activity potently prevents stroke in populations at high cardiovascular risk,” he points out. Therefore, such medical therapy “is likely to erode the potential incremental benefit from carotid revascularization.”
Dr. Kinlay concludes, “As a profession, the future of carotid revascularization depends on our courage to test optimal medical therapy with and without revascularization in randomized trials against mechanistic and patient-orientated outcomes.”
Reference:
Meta-Analysis of Randomized Trials Focusing on Prevention of the Postpericardiotomy Syndrome
Circulation 2011;123:2571-2578.
