Late complications of asymptomatic deep venous thrombosis.

Forty-one patients who had all participated in studies about prophylaxis of postoperative deep venous thrombosis (DVT) were investigated 5-8 years after operation. Twenty-five had had asymptomatic DVT detected by 125I-fibrinogen uptake test or 99mTc plasmin scintigraphy and verified by phlebography, four of which were bilateral. They received anticoagulant treatment for three months. Sixteen patients had normal screening tests. At the follow up legs in which DVT had previously been diagnosed were compared with normal legs in patients who did not have DVT. There was no significant difference in subjective symptoms between the two groups of legs, although there were more complaints of oedema and restlessness in legs in which DVT had been diagnosed and varicose veins were more common. When the incidence of varicose veins before the operation and at the follow up was compared, more patients who had had a DVT had developed varicose veins. Blood volume and venous refilling time were measured by strain gauge plethysmography, and were significantly lower in those with a history of DVT than in normal legs. The results indicate impaired venous function in patients who previously had had asymptomatic DVT treated with anticoagulants.