Our aim was to analyze patients diagnosed with left-sided portal hypertension prospectively and to document the complications at follow-up. Twenty-four patients with isolated splenic vein thrombosis (diagnosed by ultrasonography or angiography or intraoperatively) and/or isolated fundal varices (diagnosed by endoscopy or endosonography) were involved in this study. Demographics, clinical presentation, diagnostic and therapeutic procedures, and morbidity and mortality were recorded in their follow-up. There were 11 and 13 left-sided portal hypertension cases associated with pancreatic diseases and nonpancreatic disorders, respectively. Chronic abdominal pain and gastrointestinal bleeding were the two most common complaints. All patients except one had isolated esophageal (2 cases) or fundal (21 cases) varices. Thirteen patients had splenomegaly on ultrasonography. On Doppler sonography, the splenic vein could be evaluated in 21 of the 24 patients (9 and 6 had complete and partial occlusion, respectively, and 6 had patent blood flow). Urgent intervention with therapeutic endoscopy and splenectomy was performed for two patients each. Medical therapy was begun for three patients according to the underlying diseases. Three patients underwent elective surgery. Two patients were lost to follow-up after the first visit and the mean follow-up of the remaining 22 patients after diagnosis of left-sided portal hypertension was 20 months. Only one patient (with pancreas cancer) had gastrointestinal bleeding at follow-up. All patients with pancreas and gastric cancer died within 2-12 months. Left-sided portal hypertension has various etiologies. It may be difficult to diagnose this entity both endoscopically and radiologically. Treatment should be directed at the underlying diseases. Recurrent hemorrhage due to left-sided portal hypertension is not usual and the prognosis depends mainly on the underlying etiology.