The occurrence of the post-thrombotic changes after an acute deep venous thrombosis. A prospective two-year follow-up study.

BACKGROUND: The aim of the study is to investigate the development of subjective and objective findings during the first two years after DVT (deep venous thrombosis).

METHODS: This prospective two-year follow-up study was established in Tampere University Hospital in Finland. Twenty-six patients with a two-year follow-up after a phlebographically confirmed DVT were followed. Patients were treated conventionally with heparin and warfarin. Phlebography was repeated 7 months after DVT. Color-flow duplex imaging (CFDI) was performed in both legs 7 and 20 months after DVT. The subjective symptoms in both legs were recorded at the beginning and at the end of the follow-up. The development of venous reflux, obstruction and subjective symptoms after DVT were studied.

RESULTS: 50% of the legs with DVT had a pathological (deep reflux or obstructive change) CFDI-finding in the popliteal segment after a 20-month follow-up. The pathological findings in the control legs were rare. The rate of recanalisation was high. There was no difference between calf and more proximal DVTs. Pain (62%), oedema (46%) and pigmentation (35%) were common and only 27% of the legs with DVT were asymptomatic.

CONCLUSIONS: The development of the post-thrombotic syndrome begins quite early. The frequency of the subjective symptoms is high. Calf DVT may lead to postthrombotic sequelae in the popliteal segment.