Central splanchnic venous thrombosis. Often unsuspected, usually uncomplicated.

Despite the increasingly frequent noninvasive detection of central splanchnic venous thrombosis (CSVT), its pathophysiology and clinical significance remain incompletely understood. We reviewed 50 consecutive cases of partially or totally occlusive thrombosis, primarily of the portal (60%) and splenic (40%) veins. Thirty-eight percent of patients had cancer; 26% had portal hypertension or other conditions associated with splanchnic venous stasis; and in 20%, thrombosis developed postoperatively. Angiography (89%), duplex ultrasonography (46%), CT scan (32%), and MRI (16%) were all useful diagnostic modalities. In 58% of cases, CSVT was clinically unsuspected, and 32% of patients were essentially asymptomatic. Variceal hemorrhage occurred in 30% of cases, and abdominal pain was notable in 26%. Whereas 50% of patients died < or = 6 months of diagnosis, only one of these deaths was directly attributable to CSVT; the remainder were secondary to underlying disease unrelated to the CSVT itself. CSVT, increasingly detected but often unsuspected clinically, is characterized by a self-limited and nonlethal course in the majority of patients. Death from associated disease is, however, common. The treatment and prognosis of CSVT should therefore be dictated by its clinical manifestations and the setting in which it occurs, rather than by the venous thrombosis itself.