Abstract
Background Atherosclerosis is a known risk factor for flap loss in microsurgery. Several microsurgical
techniques, like plaque removal, have been proposed for atherosclerotic vessels, but
these techniques often induce intimal injuries. The aim of this study was to investigate
the impact of various endothelial defects on the risk of thrombosis in a rat acute
intimal injury model.
Methods Endothelial defects of various forms and sizes were created in the abdominal aorta
of 30 male Wistar rats following a strict protocol. Defect sizes were measured and
classified as round, horizontal, or vertical based on their configuration. An hour
after reestablishing the blood flow, the abdominal aorta was harvested and the operation
site was assessed for signs of thrombosis clinically and using light microscopy. Univariate
and multiple linear regression analysis were performed to identify possible influencing
factors on thrombosis.
Results The mean defect size was 2.65 ± 1.19 mm2. Intimal lesions were classified as round in 36.7%, horizontal in 33.3%, and vertical
in 30% of specimens. Thrombus formation was detected in 46.7% clinically and in 50%
histologically. Univariate regression analysis revealed that defect size (p = 0.048) and vertical form (p = 0.017) were significantly associated with thrombus formation. Multiple regression
analysis corroborated vertical defects as a risk factor for thrombosis (p = 0.03).
Conclusion Endothelial injuries are associated with a high risk of thrombosis with highest risks
associated with vertical defects. Arteries should be carefully examined for intimal
defects before microvascular anastomosis, especially in the atherosclerotic patient.
Keywords
microsurgery - acute intimal injury - atherosclerosis
