Back to Annual Symposium Program

Objective The present standard for the diagnosis of carotid arterial disease is color-flow duplex ultrasound performed by a vascular technologist. This expensive equipment and required expertise precludes cost-effective routine screening. An inexpensive hand-held ultrasound device has been developed and utilized in a prospective clinical trial utilizing nurses in a primary care setting.
Methods The ultrasound unit consists of a continuous-wave vector Doppler system with six receiving transducers and a central transmitter. It is only 1.5 inches in diameter and 4 inches in length and accurately measures peak systolic velocity (PSV) independent of angle of insonation. Patients were selected for screening if they were 65 years or older and had one or more risk factors: HTN, CAD, dyslipidemia or smoking. All were asymptomatic and without prior CVA or CEA. Those found to have a PSV of > 140 cm/sec had a full duplex ultrasound examination by an experienced registered vascular technologist.
Results A total of 938 individuals at four primary care offices participated in the study. They consisted of 476 females and 462 males. The time required to perform the examination was 4.4 ± 1.3 minutes. Of this entire group, 218 (23%) patients had a positive finding with a PSV > 140cm/sec and were referred for a complete duplex ultrasound examination. Of the 191 vessels suggested on screening to have carotid disease, 13% had > 50% carotid stenosis, 18% had 16-49% stenosis, 42% had more mild disease and the remaining 27% were normal. Utilizing published cost-effectiveness models, these results suggest a cost of less than \,000 per quality-adjusted life-year with this carotid screening unit and protocol.
Conclusions A hand-held inexpensive ultrasound instrument can be used by non-specialized nursing staff in primary care offices to rapidly screen for carotid arterial disease. Such a device and clinical protocol would make carotid screening appropriate and cost-effective.