The inhibition of neointima formation by increased blood flow was abolished with hypertensive and nonhypertensive doses of the nitric oxide synthase inhibitor L-NAME, which suggests that the L-NAME effects are independent of systemic hemodynamic alterations. It is concluded that flow-induced inhibition of neointima formation is mediated in part by nitric oxide.

No abstract

The natural history of venous reconstruction (VR) in terms of patency and clinical outcome after vascular trauma has not been well documented. This study consists of 32 patients who had VR performed for extremity vascular trauma and were available for long-term assessment (mean follow-up time 49 months, range 6 to 108 months). The types of repair performed were as follows: lateral venorrhaphy (simple repair) (56%), interposition grafting (22%), patch repair (12.5%), and end-to-end repair (9.5%). Seventeen patients underwent venography after the operation with documentation of repair patency in eight patients (46%) and thrombosis in nine (54%). Only two patients had significant clinical edema at follow-up examination. Noninvasive venous evaluation consisted of Doppler ultrasonography, impedance plethysmography, photoplethysmography, and color-flow duplex scanning (CFDS). The photoplethysmography-derived venous refilling time of the injured extremity was 34.9 +/- 16.2 seconds whereas that of the contralateral noninjured extremity was 36.8 +/- 16.1 seconds (p = 0.5). Based on standard criteria for CFDS, 90% of VRs were patent. Eight repairs that were patent in the early postoperative period remained patent on CFDS. Of the nine repairs with early thrombosis, eight were assessed as patent on follow-up CFDS. In conclusion, VR is a durable surgical procedure associated with minimal morbidity, good long-term patency, and preservation of venous competence. The natural history of thrombosed VRs appears to be one of thrombus absorption with recanalization.

No abstract