[Serum levels of Apo-AI and B as markers of synthetic graft stenosis after bypass for peripheral artery disease]

BACKGROUND

Hyperlipidemias are the main risk factors for atherosclerosis and cardiovascular disease. Nevertheless, the protein fractions of these lipids such as apolipoprotein B (Apo-B) can lead to arterial obstruction. In this study we investigated levels of apolipoproteins AI and B in patients with chronic occlusive peripheral arterial disease (PAD) of the lower extremities and their association with either patency or stenosis of synthetic grafts.

METHODS

This cohort study included 24 patients with chronic occlusive PAD who underwent infrainguinal revascularization with polytetrafluoroethylene (PTFE) synthetic graft. Patients were divided into two groups according to whether or not they were exposed to Apo-B, thus integrating two cohorts: the unexposed group (group 1, normal levels of Apo-B) and the exposed group (group 2, high levels of Apo-B). Variables investigated at 3, 6 and 12 months included arm/ankle index (AAI) and its association with levels of Apo-AI and Apo-B, and levels of cholesterol, triglycerides, and fibrinogen.

RESULTS

The study was comprised of 67% men and 33% women. Average age was 65.2 +/- 8.4 years. There was a correlation between AAI and high levels of Apo-B (p <0.001). Apo-AI levels were not significantly different between groups. Fibrinogen remained elevated in both groups with no statistical difference. Triglycerides demonstrated a significant difference between groups in basal measurements (p <0.05). Cholesterol remained normal in both groups without statistical difference.

CONCLUSIONS

This study demonstrates that patients exposed to high levels of Apo-B had synthetic graft failure (obstruction), as demonstrated by AAI <1.