Physiologic risk factors increase risk of myocardial infarction with transcarotid artery revascularization in prospective trials.

Objective: Patients can be considered at high risk for carotid endarterectomy (CEA) because of either anatomic or physiologic factors and will often undergo transcarotid artery revascularization (TCAR). Patients with physiologic criteria will be considered to have a higher overall surgical risk because of more significant comorbidities. Our aim was to study the incidence of stroke, myocardial infarction (MI), death, and combined end points for patients who had undergone TCAR stratified by the risk factors (anatomic vs physiologic).

Methods: An analysis of prospectively collected data from the ROADSTER (pivotal; safety and efficacy study for reverse flow used during carotid artery stenting procedure), ROADSTER 2 (Food and Drug Administration indicated postmarket trial; postapproval study of transcarotid artery revascularization in patients with significant carotid artery disease), and ROADSTER extended access TCAR trials was performed. All 851 patients were considered to be at high risk for CEA and were included and stratified using high-risk anatomic criteria (ie, contralateral occlusion, tandem stenosis, high cervical artery stenosis, restenosis after previous endarterectomy, bilateral carotid stenting, hostile neck anatomy with previous neck irradiation, neck dissection, cervical spine immobility) or high-risk physiologic criteria (ie, age >75 years, multivessel coronary artery disease, history of angina, congestive heart failure New York Heart Association class III/IV, left ventricular ejection fraction <30%, recent MI, severe chronic obstructive pulmonary disease, permanent contralateral cranial nerve injury, chronic renal insufficiency). For trial inclusion, asymptomatic patients were required to have had ≥80% carotid stenosis and symptomatic patients to have had ≥50% stenosis. The primary outcome measures were stroke, death, and MI at 30 days. The data were statistically analyzed using the χ test, as appropriate.

Results: A total of 851 high surgical risk patients were categorized into two groups: those with anatomic-only risk factors (n = 372) or at least one physiologic risk factor present (n = 479). Of the 851 patients, 74.5% of those in the anatomic subset were asymptomatic, and 76.6% in the physiologic subset were asymptomatic. General anesthesia was used similarly in both groups (67.7% anatomic vs 68.1% physiologic). MI had occurred in eight patients in the physiologic group (1.7%), all of whom had been asymptomatic and in none of the anatomic patients (P = .01). The combined stroke, death, and MI rate was 2.1% in the anatomic cohort and 4.2% in the physiologic cohort (P = .10). Stratification of each group into asymptomatic and symptomatic patients did not yield any further differences.

Conclusions: The patients who had undergone TCAR in the present prospective, neurologically adjudicated trial because of high-risk physiologic factors had had a higher rate of MI compared with the patients who had qualified for TCAR using anatomic criteria only. These patients had experienced comparable rates of combined stroke, death, and MI rates. The anatomic patients represented a healthier and younger subset of patients, with notably low overall event rates.