PVD: Screening
Patients with peripheral vascular occlusive disease have a significant risk of disease involving other vascular beds. Carotid stenosis exceeding 50% may be found in as much as 20% of asymptomatic patients: nearly 15% have a greater than 75% carotid stenosis. (The absence of a carotid bruit is not sufficient to exclude a significant stenosis). Although intermittent claudication from all causes is associated with a doubling of patient mortality, those patients with large vessel peripheral vascular disease are known to have a four-fold increase in overall mortality. If the disease is both symptomatic and severe the ten-year mortality rates are increased by as much as 15-fold. The five-year mortality rate for patients with claudication is 29 per cent: 60% of these deaths result from coronary artery disease, 15% from cerebrovascular disease and the remainder from non-atherosclerotic causes. Unfortunately, hemodynamically significant large vessel disease is frequently asymptomatic. Routine physical exam findings alone may not correlate well with significant proximal disease.
Our initial approach to the diagnosis of large vessel peripheral vascular disease is initiated by the routine use of an interview questionnaire, vascular physical examination, and measurement of the Ankle-Brachial Index (ABI).
The routine use of ABI measurements* in our office has been a very valuable screening tool for the at-risk patient. It is performed by doppler measurement of the highest pressure in the posterior tibial or dorsalis pedis artery and compared to the highest brachial artery pressure.
We have favored the San Diego Claudication Questionnaire as a screening tool for the initial assessment of our patients. It has been shown to have a sensitivity of xxx% and a specificity of xxx% and is a very useful screening tool in the at risk population.
The most sensitive and specific physical finding associated with large-vessel atherosclerotic disease is an abnormality of the posterior tibial pulse. With our use of both of these tools, we are effectively able to screen our patients, obtain additional diagnostic interventions as needed, and initiate therapies to modify known cardiovascular risk factors such as cigarette smoking, hypertension, and hyperlipidemia. Other effective therapies may include antiplatelet agents, exercise, and medications specifically designed to suppress platelet aggregation and induce arterial vasodilation.
Given the prevalence of significant large vessel vascular disease, we urge you to consider initial screening for multisystem vascular disease in your at risk patients. Potentially, risk factors such as sedentary lifestyle, obesity, and glucose intolerance can be addressed to reduce longterm morbidity and mortality.