OBJECTIVESTo confirm the occurrence time of iliac-femoral post-thrombotic syndrome (IFPTS) with the experimental analysis of fibrinolytic activation and vessel wall remodeling after iliofemoral vein thrombosis (IFVT). To explore the optimal timing of surgery for IFPTS with comparative study of surgical effect after early and late treatment.

METHODSIFVT was performed on 20 SD rats. The plasminogen activation [tissue-type plasminogen activator (tPA) and urokinase-type plasminogen activator (uPA)] and vascular remodeling (positive rates of internal elastic membrane, vascular perimeter and vessel wall stiffness index) were detected by immunohistochemistry and Weigert Van Gieson staining respectively. Fifty-one IFPTS patients with Palma-Dale treatment from January 1990 to December 2005 were divided into early surgical group (1 to 2 months after IFVT) and later surgical group (> 2 months after IFVT), including 20 patients and 31 patients respectively. Treatment effects were evaluated by venous clinical severity score (VCSS).

RESULTSThe positive rate of internal elastic membrane decreased significantly at the 4th, 8th and 12th week (P < 0.01), while the vessel wall stiffness index increased at the same time (P < 0.01). The vascular perimeter elevated obviously at 12th week (P < 0.05). Symptoms of early treatment group improved significantly after surgery (3.4 ± 0.9 vs. 5.2 ± 1.2, P < 0.05). Whereas the late treatment group had no significant changes of symptoms (6.8 ± 1.7 vs. 7.6 ± 3.0, P > 0.05).

CONCLUSIONSThe present findings suggest that IFPTS occurs around first month after IFVT. Acceptable surgery timing for IFPTS exists at 1 to 2 months post-IFVT.