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Underlying factors influencing the development of the post-thrombotic limb.

PURPOSE
This study was designed to determine whether patients having underlying venous disease in their contralateral limbs indicates a more severe long-term clinical outcome in the ipsilateral limb after a deep vein thrombosis (DVT) and to determine what other factors may influence the long-term outcome.


METHODS
An acute DVT was initially diagnosed by means of duplex ultrasound scanning. Follow-up clinical examinations and bilateral duplex reflux studies were performed for a mean period as long as 3 years. The patients were divided into two groups: group I, those with no history of a contralateral DVT, and group II, those with a history of a contralateral DVT. The patients were classified at their final examination according to the Clinical, Etiology, Anatomic, Pathophysiologic (CEAP) classification, and the ipsilateral and contralateral limbs were compared. Predisposing factors were compared with the final clinical outcome.


RESULTS
Sixty-three patients were monitored in a mean follow-up period of 3 years. There was a significant difference in the incidence of symptoms between the ipsilateral limbs (P <.01) and the contralateral limbs (P <.001) for both groups. There was no significant difference between the incidence of superficial reflux between the ipsilateral and contralateral limbs, but the deep venous system and perforator veins were involved more often in the ipsilateral limbs. In group I, only six patients (10%) had no evidence of venous dysfunction (CEAP = 0) in their ipsilateral or contralateral limbs at the time of the final examination, and all patients had reversible risk factors. Of patients who had a mild clinical outcome (CEAP score, 1 to 3), 64% had a healthy contralateral limb, and the remaining 36% had mild to moderate disease. Eighty percent of patients with the most severe clinical outcome (CEAP > 3) had mild to moderate venous disease in their contralateral limb and had nonreversible risk factors.


CONCLUSION
There are a significant number of patients with an acute DVT who had an underlying venous disease in the uninvolved contralateral limb. An ipsilateral post-thrombotic limb is more likely to develop in patients with primary venous reflux after an acute DVT. The level of venous dysfunction in the contralateral limb is an indication of the severity of disease developing in the ipsilateral limb. The initial risk factors of the patients have an influence on the final clinical outcome.