Azygos venous blood flow while fasting, postprandially, and after endoscopic variceal ligation, measured by magnetic resonance imaging.

Using cine phase-contrast magnetic resonance (MR) imaging, we measured fasting and postprandial azygos blood flow in 15 cirrhotic patients with portal hypertension and 11 healthy controls. In 10 of the cirrhotics, measurements were made before and after prophylactic endoscopic variceal ligation therapy (EVL). Flow volume was measured in the azygos vein at the level of the midthoracic vertebra. Azygos blood flow was measured under basal fasting conditions and 30-40 min after ingestion of a 500 Kcal meal. Fasting azygos blood flow was 139 +/- 43 ml/min in controls vs 519 +/- 249 ml/min in cirrhotics (P < 0.01). Eating significantly increased azygos blood flow, by 38% in controls (P < 0.02) and by 27% in cirrhotics (P < 0.02), compared with fasting conditions. EVL markedly decreased azygos blood flow, by 25% compared with pre-EVL (P < 0.03). The cine phase-contrast MR velocity mapping method measured flow volume in the azygos veins. Azygos blood flow was markedly greater in the cirrhotics than in the controls. In the cirrhotics and controls, blood flow volume increased after eating. Azygos blood flow was significantly reduced by successful EVL.