Factors affecting splanchnic haemodynamics in Crohn's disease: a prospective controlled study using Doppler ultrasound

Background—Current knowledge on splanchnichaemodynamics in Crohn's disease is limited.
Aims—To investigate which features of Crohn'sdisease affect splanchnic haemodynamics, and to establish whetherportal vein (PV) and superior mesenteric artery (SMA) blood supplyreflects clinical or biochemical activity of Crohn's disease.
Methods—Seventy nine patients with Crohn'sdisease and 40 controls were evaluated by Doppler ultrasound (US). Themean velocity of PV and SMA flow, the volume of blood flow of the PVand SMA, and the resistance index of SMA were studied. A series ofclinical, biochemical, and US variables including Crohn's diseaseactivity index, serum C reactive protein concentrations, diseaseduration and its anatomical location, smoking habits, abdominalcomplications, and current medical therapy, as well as the maximumbowel wall thickness as measured by US, were determined. The relationbetween PV and SMA blood flow and these variables was assessed byunivariate and multivariate analysis.
Results—Patients with Crohn's disease hadsignificantly higher PV and SMA flow and a lower SMA resistance indexthan controls. Stepwise multiple regression analysis identified bowelwall thickness and location of the disease as the main predictivevariables of both PV and SMA blood flow variation, accounting for 36%and 45% of their variability, respectively. No relation was foundbetween splanchnic haemodynamics and disease activity.
Conclusion—A hyperdynamic mesenteric circulationdoes exist in Crohn's disease; however splanchnic blood flow does notreflect the clinical or biochemical activity of the disease, but seems to be linked more to other Crohn's disease characteristics, such asmaximum bowel thickness and anatomical location.

Keywords:Crohn's disease; Doppler ultrasound; splanchnicblood flow