Value of renal resistive index in hepatitis C virus related liver cirrhosis and its response to midodrine

BackgroundHyperdynamic circulatory state in liver cirrhosis is characterized by increased splanchnic blood flow and renal vasoconstriction.AimTo evaluate the relationship between renal resistive indices (RI) and HCV liver cirrhosis severity and RI value in predicting 6month survival of those patients. Also we aimed to assess the effect of midodrine on RI.Patients and methods120 patients with HCV liver cirrhosis and 40 healthy controls were enrolled in the study. INR, total bilirubin, albumin, creatinine and sodium were measured in all patients. Both patients and controls underwent abdominal ultrasound with duplex Doppler examination of the kidneys with RI calculated. Patients were followed for 6months. Surviving patients with highest risk underwent renal duplex with RI calculation (RI2). They then received oral midodrine at a dose of 7.5mg three times daily for 3months with revaluation of RI (RI3).Results57 (47.5%) patients had high RI (RI>0.7) while 63 (52.5%) patients had normal RI. Patients had significantly higher RI than healthy controls (P<0.001). There was a significant positive correlation between RI and MELD, MELD-Na, and Child class (r=0.859, r=0.769, rho=0.56 respectively and P<0.001). Patients with RI>0.73 are at higher risk of death within 6months (P<0.001). Administration of midodrine resulted in no significant difference in RI in the 37 surviving patients with baseline RI>0.73 (P=0.1605).ConclusionRI is strongly correlated with liver cirrhosis severity and had comparable prognostic value with MELD score. Midodrine had no significant effect on RI in high risk patients