Incidence and significance of microscopic pathological lesions found in pedicle and recipient vessels used in microsurgical breast reconstruction

Abstract

The purpose of this study was to assess the incidence of abnormal vascular histology and to determine whether or not this was correlated with the incidence of postoperative microvascular problems. The microvascular histology of both donor and recipient vessels was studied in 38 patients (40 flaps) undergoing breast reconstruction with free TRAM flaps. Preoperative risk factors were assessed and correlated with histological changes in vessels, and both were tested against anastomotic complications. Thrombosis of either the artery or the vein of the flap was seen in 6 cases (15%), and of these, two flaps failed completely and one suffered partial necrosis. The occlusion affected the arterial anastomosis in 3 patients, and the venous anastomosis in 2 patients, while both the artery and the vein were thrombosed in one case. Preoperative risk factors such as smoking, obesity, radiotherapy, and chemotherapy were not associated with a significantly higher incidence of thrombosis or with significant histological abnormalities in vessels (P value varied between 0.3-0.06). Microvascular histology showed variable degrees of pathological changes in six flaps (15%); nevertheless, in this group, only one flap suffered a venous thrombosis, which ended in total flap loss. Among those with one or more risk factors (24 patients), only 2 had some evidence of histological abnormality of the blood vessels used for the microvascular anastomosis (P = 0.2).

A Review of Radiation-Induced Vascular Injury and Clinical Impact

“…Large vessels are generally more resistant, although arterial thrombosis has been reported. Radiation-induced vascular structural changes are of particular interest given numerous clinical investigations suggesting that microvascular surgery in irradiated blood vessels carries with it a higher risk of thrombosis due to preexisting vessel wall damage 5 . One such study was that of Barrera-Ochoa et al 6 who observed that irradiated vein anastomoses in rats have higher failure rates than nonirradiated recipient vessels.…”

“…Radiation-induced vascular structural changes are of particular interest given numerous clinical investigations suggesting that microvascular surgery in irradiated blood vessels carries with it a higher risk of thrombosis due to preexisting vessel wall damage. 5 One such study was that of Barrera-Ochoa et al 6 who observed that irradiated vein anastomoses in rats have higher failure rates than nonirradiated recipient vessels. In this context, it is critical to understand the molecular events leading to vascular endothelium damage after irradiation.…”