Hepatic Artery Doppler Indices in Children with Extra Hepatic Portal Vein Obstruction

Abstract

Doppler measurement provides information on the hemodynamics in the hepatic artery and the portal venous system. Aim: To study the hepatic artery hemodynamics in children with extra hepatic portal vein obstruction. Materials and methods: Hepatic artery indices were studied using Doppler indices in 15 children (<12 years) with extra hepatic portal hypertension (EHPVO) and obliterated esophageal varices. The hepatic artery resistive index, the arterial acceleration time and the acceleration index were used to determine the flow pattern within the hepatic artery. Controls were 15 healthy age-sex matched children, belonging to the same socioeconomic strata in absence of liver disease. Results: The mean age of the children was 8.43 ± 3.2 years and male female ratio was 4:1. All the children had obliterated esophageal varices. The hepatic artery resistive index in the children with EHPVO was normal and similar to controls. The hepatic arterial early systolic acceleration index was significantly higher in cases compared to controls (436 ± 290 vs 214 ± 100; P value <0.004). The hepatic arterial acceleration time though low in the cases (86 ± 35 cm/s) was not statistically different from the controls (128 ± 14 cm/s). Conclusion: There was a significant increase in hepatic arterial early systolic acceleration in children with chronic EHPVO. The latter may be responsible for an increase in hepatic arterial in flow velocity in a slow flow system despite a normal resistive index. Congestive index and venous pulsatility index in the portal vein, both in adult and pediatric patients are determinants of the hemodynamic status of the portal system. 8,9These indices are not reliable in portal vein thrombosis and portal cavernoma as there is a poor correlation between the size of the portal vein and portal pressure. 7,10 Also, the transformation of the portal vein to a cavernoma makes measurement of these indices difficult.Hepatic artery indices are likely to be more informative 11 under such circumstances. One can get a clue to the hemodynamics of the blood flow in the hepatic artery. Till date, there are no published studies that have reported on hemodynamics in hepatic artery in patients with cavernomatous transformation of the portal vein.McNaughton et al 12 describes the normal hepatic arterial waveform in the hepatic artery to be pulsatile with low resistance. The peak height of the wave corresponds to the peak systolic velocity (V 1 ), and the trough to enddiastolic velocity (V 2 ) The normal resistive index (RI) within the hepatic artery ranges from 0.55 to 0.8. Any measured RI above or below the normal range represents a disease state. 13-15The aim of the present study was to determine the hepatic artery resistive index, the acceleration time and the acceleration index in children with EHPVO. MATERIALS AND METHODSThe Liver Unit at Stanley Hospital predominantly caters to the adult population. The present study included 15 children with EHPVO who were referred to the Liver Clinic for management of variceal bleed. All these...

Correlation of hepatic artery resistive index with portal pressure and serum nitric oxide levels in patients with extrahepatic portal vein obstruction

“…did not find any significant difference in HARI values in EHPVO patients being treated medically as compared to controls. [11]…”