Retrospective Analysis Of Post-Thrombotic Syndrome Complicted With Arteriovenous

Objective:To analyze and summarize the clinical characteristics, imaging features and surgical treatment of post-thrombotic syndrome complicated with arteriovenous fistula, and try to investigate the preliminary etiology.Methods:Retrospective analysis of the clinical data of post-thrombotic syndrome complicated with arteriovenous fistula(PTS+AVF group), admitted by the vascular surgery of Shandong provincial hospital from January2006to January2014. At the same time the control group was post-thrombotic syndrome (PTS group) secondary to left lower extremity iliac-popliteal thrombosis. The study included the age, sexual classification, initial swelling time and aggravation, lower limb circumference, distribution and characteristic of superficial varicose veins, the distribution of pigmentation and ulcer, deep vein patency in lower extremity, type and location of arteriovenous fistula, surgical treatment strategy, the difference of iliac venous pressure before and after treatment, and postoperative follow-up of iliac vein stent and great saphenous vein bypass, limb swelling and pain, limb circumference, pigmentation and ulcer area. Based on series previous literatures, we preliminarily investigated the etiology of PTS+AVF, and summarized the clinical characteristic and surgical treatment strategy.Results:A total of14patients in PTS+AVF group, including10males and4females, ranging from38to84years old (the median age58years old and mean 59.07±12.40years old). A total of178patients in PTS group, male56cases, female122cases,32-78years old, the median age52years old, mean51.22±11.32years old. There was a statistically significant difference of age distribution between the two groups (t=-2.368, p=0.033). Patients of the two groups mainly presented with limb swelling, pain, superficial varicose veins, pigmentation and ulcer. However, patients of PTS+AVF group were characterized by thigh swelling and sudden aggravation, while patients of PTS group presented with recurrent limb swelling. On physical examination, varicose vein accompanied by elevated skin temperature mainly located at lower abdomen, groin and inner thigh in PTS+AVF group, and varicose vein wasn’t correlated with the position. On the contrary, varicose vein with normal skin temperature was observed in lower abdomen, perineum and inner thighs in PTS group, and varicose vein was affected by position. On imaging examination, lower limb lymphedema occurred in all patients of two groups. Recanalized (<5%) or occluded left iliac vein and recanalized (40%-100%) popliteal vein were observed in patients of PTS+AVF group with mean iliac venous pressure difference of27±3.25cmH2O. Multiple and tiny arteriovenous fistulas distributed throughout the lower extremities. Angiography showed incomplete imaging of popliteal vein, femoral vein and iliac vein, the collateral vein, and the early imaging of all visible veins. In patients of PTS group, recanalized (>20%) iliac vein, some of which was severely stenosis or occluded, with mean iliac venous pressure difference of18±3.17amH2O. Significant collateral venous drainage at the end of the external iliac and behind femoral total vein can be found. On surgical treatment, all patients in PTS+AVF group underwent surgical treatment, including venous fistula ligation in1patient, arteriovenous fistula embolization in5cases followed by iliac venous balloon expansion and stent implantation in5patients, and autogenous great saphenous vein pubis on cross flow operation in5cases. In PTS group,26patients underwent iliac venous balloon expansion and stent implantation, and38patients underwent Palma-Dale surgery. All patients were improved or cured before discharging hospital. During follow-up, in PTS+AVF group, postoperative symptoms were alleviated in1case after arteriovenous fistula resection and3cases after arteriovenous fistula embolization. Recurrent symptoms were observed in2cases after embolization. Symptoms and signs were improved in10patients after iliac venous balloon expansion and stent implantation or Palma-Dale surgery. Ultrasound revealed decreased arteriovenous fistula in all patients, a complete disappearance in2cases, occluded iliac vein sent in1case, and patent bypass vein in5cases. In PTS group, swelling and pain were improved in all patients, ulcer recurrence in2cases. Ultrasound revealed occluded iliac vein stent in4patients and occluded bypass vein in7patients.Conclusions:Post-thrombotic syndrome complicated with arteriove nous fistula predominantly presented with lower extremity post deep venous thrombosis syndrome, and also presented some symptoms of arteriovenous fistula. Vascular doppler ultrasound examination is a simple and highly accurate screening examination. Lower limb blood vessel angiography is a gold standard for the diagnosis of the disease. Old age may be one of the most risk factors. Characteristics of these patients included:(1) The main symptoms are the swelling of the left leg, mainly on the thigh, not pitting edema, aggravating in a short time, sometimes lymphedema merged.(2) The varicose superficial vein appear in the lower abdomen, inner thigh and the left groin area, Varicose veins have nothing to do with the position.(3) Ultrasond and angiography suggested severe stenosis or occlusion in left common iliac vein and distal recanalized, Iliac vein pressure difference in PTA+AVF was obviously higher than that of patients with PTS.(4) Arteriovenous fistula was widely distributed, mainly as tiny fistula branches, The entire limb can be affected, but the confluence of iliac internal and external iliac confluence was predominantly affected, may due to the crossed or compressed blood vessels. Treatment means to reduce lower limb venous pressure. Traditional arteriovenous fistula ligation and arteriovenous fistula embolization treatment are not recommended due to poor efficacy. Palma-Dale surgery and iliac vein balloon dilatation and stent implantation not only can effectively improve the symptoms of lower extremity, but also reduced the number of arteriovenous fistula significantly. So we speculated that reduction of limb vein high pressure is helpful to reduce the occurrence of arteriovenous fistula, but the mechanism still needs further research. Organization and recanalization of deep vein thrombosis, high lower limb vein pressure, abnormal secretion of vascular growth factors contributed to post-thrombotic syndrome complicated with arteriovenous fistula, but the specific mechanism is still unclear and requires further research.