Carotid endarterectomy saphenous vein patch rupture revisited: selective use on the basis of vein diameter.

Purpose: The single major disadvantage of carotid endarterectomy (CEA) patch reconstruction with greater saphenous vein (GSV) is central patch rupture, which has a reported incidence of 0.5% to 4%. This is a prospective evaluation of the selective use of GSV for a CEA patch based on previously established vein diameter criteria.

Methods: Between 1988 and mid-1995, 534 of 671 CEAs (80%) were reconstructed with GSVs that had a distended diameter > or = 3.5 mm. Thigh veins were used in all 252 women who underwent CEA. Of the 282 men who underwent CEA, 265 GSVs (94%) were harvested from below the knee and 17 from the thigh. During this period four thigh and 13 below-knee veins (3.2%) were rejected because the diameter was < 3.5 mm, and a synthetic patch was used instead. In 408 of the CEAs with GSV (76%) the vein rupture pressures and diameters were measured, the CEA geometry was measured, and the predicted CEA vein patch rupture pressures were calculated.

Results: No GSV patches ruptured in this series. This compares favorably with three patch ruptures in 239 previous CEAs when no vein diameter criteria was used (p = 0.03). This also compares favorably with a multicenter series of 13 GSV patch ruptures (0.73%) in 1773 CEAs (p = 0.03) and with a single-center series of eight ruptures (0.47%) in 1699 CEAs (p = 0.05). GSV diameters were 4.9 +/- 0.9 mm (mean +/- 1 SD); vein rupture pressures, 3.9 +/- 1.5 atmospheres; carotid bulb major axis diameters, 12.5 +/- 1.6 mm; carotid bulb maximum diameters of curvature, 14.2 +/- 2.2 mm; and CEA patch rupture pressures, 1.3 +/- 0.6 atmospheres (range, 280 mm Hg to 4 atmospheres). CEA vein patch rupture pressure correlates positively with vein diameter (p < 0.001, slope), but there is wide variability (correlation coefficient = 0.39). The 14 CEAs (3.4%) with predicted rupture pressures < 400 mm Hg were performed with veins 3.5 to 5.5 mm in diameter (mean, 4.2 mm), and all had carotid bulb major axis diameters > 12 mm (mean, 15.3 mm). Eight of these CEAs were reconstructed with thigh veins.

Conclusions: Use of GSVs with a distended diameter > or = 3.5 mm for CEA patch reconstruction significantly reduces the probability of central patch rupture; however, a few CEAs reconstructed with veins > 3.5 mm in diameter and large carotid bulbs have predicted patch rupture pressures < 400 mm Hg. Because at times some veins will have rupture pressures lower than desirable, CEA reconstruction should be tailored to keep the carotid bulb major axis diameter < 13 mm.