Relationship of lower extremity skin blood flow to the ankle brachial index in patients with peripheral arterial disease and normal volunteers.

Changes in posture of the lower extremities induce changes in skin blood flow, known as veno-arteriolar response (VAR). We investigated the relationship between ankle brachial index (ABI) and VAR in patients (ABI<0.9) with peripheral arterial disease (PAD) and age-matched normal controls (ABI>1). We measured ankle pressure, ABI at rest, and post-exercise ABI. Using laser Doppler flowmetry, skin blood flow was measured with the lower extremity in extended and flexed positions and the fractional change (extended-flexed/extended) in blood flow (VAR) was calculated. With external pressure applied serially to the lower extremity in the extended position using a sphygmomanometer, the pressure (PVAR) at which the VAR was similar to that in the flexed position was recorded. Patients and controls did not differ by age or comorbidity, except higher cigarette smoking in patients (95.8% vs. 4.3%, p=0.001). VAR and PVAR were significantly lower in patients than controls (0.42+/-0.16 vs. 0.65+/-0.11 flux/min, p=0.001 and 29+/-8 vs. 48+/-9 mm Hg, p=0.001, respectively). There was significant correlation between ABI-post and VAR (r=0.6, p=0.01) and between the VAR and PVAR (r=0.8, p=0.001). VAR<0.3 flux/min was 100% sensitive, 80% specific, and area under curve of 0.88, p=0.001 for detecting PAD as defined by ABI<0.9. Similarly, PVAR of 22 mm Hg was 100% sensitive, 85% specific, and area under curve of 0.94, p=0.001 for detecting PAD. Skin blood flow by this method correlates with the presence and severity of an abnormal ABI. This may offer a method of monitoring the effect of therapy and regression of peripheral atherosclerosis.

Usefulness of an abnormal ankle-brachial index to predict presence of coronary artery disease in African-Americans.

We sought to determine the role of an abnormal ankle-brachial index (ABI) in an African-American population with suspected coronary artery disease (CAD) referred for diagnostic coronary angiography. In this population, an ABI < or =0.90 predicted the presence of > or =3-vessel or left main CAD with a sensitivity of 85% and specificity of 77%. However, a normal ABI did not predict absence of 1- or 2-vessel CAD. These results suggest that in this population, the ABI can be used to increase the pretest probability of severe CAD.

Visceral artery pseudoaneurysms following pancreatoduodenectomy.

Pancreatic and biliary fistulas and delayed gastric emptying are the most common complications after pancreatoduodenectomy. The development and bleeding of visceral arterial pseudoaneurysms are rare phenomena and pose diagnostic and treatment dilemmas. We describe 5 recent patients who developed bleeding from visceral artery pseudoaneurysms after pancreatoduodenectomy. These patients all had "herald" bleeding from their abdominal drains. Subsequent angiography and therapeutic embolizations were successfully performed.