| • Severe cardiovascular disease |
| ‐ congestive heart failure |
| ‐ myocardial infarction 1 day or 4 weeks before |
| ‐ coronary artery bypass grafting or open heart surgery within 6 months |
| ‐ angina at a low workload or unstable angina |
| • Severe pulmonary disease |
| • Previous carotid endarterectomy with recurrent stenosis |
| • Difficult surgical access |
| ‐ at or above the second cervical vertebra |
| ‐ inferior to clavicle |
| ‐ prior radiation therapy to the neck |
| • Contralateral carotid artery occlusion |
| • Contralateral laryngeal nerve palsy |
