Circadian rhythm of fasting and postprandial portal blood flow in cirrhosis

Abstract

Objective. To examine the relationship of both the unstimulated and the postprandial portal blood flow (PVF) to the time of day and to determine its intra-individual reproducibility over time in patients with liver cirrhosis. Material and methods. In 24 cirrhotic patients, 27 PVF measurements were performed during 24 h on day 0 and day 7 using Doppler ultrasound. Three standard liquid meals were given orally. On day 7, the baseline hepatic venous pressure gradient (HVPG) was also measured. Results. Circadian area under the time curve of PVF was highly reproducible within individuals (r=0.959, p<0.001). It did not correlate with HVPG. Cosinor analysis showed a significant circadian rhythm of PVF (acrophase at 11:44 and amplitude of 9.44%). Maximal postprandial increase in PVF was significantly higher in the morning than at noon or in the evening. Conclusions. PVF is subject to a circadian rhythm and postprandial portal hyperemia shows a diurnal variability. Both are highly reproducible.

• Circadian rhythm
• Cosinor analysis
• Doppler ultrasound
• liver cirrhosis
• portal blood flow
• portal hypertension
• postprandial portal hyperemia
• reproducibility