ABI - MARKER OF CARDIOVASCULAR RISK.
The incidence of Peripheral Arterial Disease (DAP) increases significantly with the age and in many cases is asymptomatic. NATIONAL HEALTH AND NUTRITION EXAMINATION SURVEY, 1999-2000 (NHANES) reported increase 14 time in prevalence of DAP when compared age groups with 50 or fewer years and groups with 70 or more. The Framingham study found average annual incidence among men in the age group of 30 to 44 years of 6:10.000 in the range of 65 to 74 years of 61:10.000.
Several studies demonstrate objective relationship between presence of DAP and cardiovascular risk indicating the need for identification and evaluation of patients'' risk.
The evaluation Ankle-brachial Index (ABI) has been growing of importance in tracking this pathology mostly, in the selection of cases for more detailed studies and orientation for changes in the lifestyle.
ABI is a noninvasive procedure medical (of high sensibility and specificity), easy to of being performed and low cost. It consists in the measure of systolic pressure (maximum arterial pressure) in patient''s arms (brachial pulse) and patient''s leg (tibial pulse). In a healthy individual blood pressure in the leg is alike or greater than blood pressure in the arm. The index is calculated by the relationship ankle systolic pressure/brachial systolic pressure and considered normal values between 0,91 and 1,30. The lower value of the index more severe the disease and greater the cardiovascular risk.
It should be evaluated in all patients aged 65 years and over, 50 years or more who have cardiovascular risk factors (high blood pressure, dyslipidemia, diabetes, etc.), in patients of any age when they relate family history of occlusive precocious arterial disease, patients with intermittent claudication or submitted procedures for revascularization.