Nonselective beta blockers tied to portal vein thrombosis in cirrhotic patients
Exposure to nonselective beta blockers contributes to an increased risk of developing portal vein thrombosis in patients with cirrhosis, a study suggests.
The study included 97 outpatients with cirrhosis and no portal vein thrombosis at baseline, of whom 50 percent were on nonselective beta blockers. Researchers performed Doppler ultrasound every 3 or 6 months for a median follow up of 19 months.
Portal vein thrombosis occurred in 11 patients (10.2 percent) during follow-up. Occlusion of the portal vein was complete in two patients and partial in nine. Most of the patients were male (54.6 percent male) and had Child-Pugh A cirrhosis (81.8 percent).
Significant risk factors for incident portal vein thrombosis included nonselective beta blockade (hazard ratio [HR], 10.56; 95 percent CI, 1.35–82.73; p=0.025) and a history of medium- or large‐sized oesophageal varices at baseline (HR, 5.67; 1.49–21.63; p=0.011).
Conversely, heart rate and portal blood flow velocity at baseline showed no association with the risk of portal vein thrombosis, although the two variables were significantly improved by nonselective beta blockers.
Researchers pointed out the need for further investigation to characterize the mechanisms that explain portal vein thrombosis development in cirrhotic patients on nonselective beta blockers in order to optimize targeting of nonselective beta blockers in this population.
Nonselective beta blockers is the gold standard in the prevention of first and recurrent variceal bleeding. The goal is to lower portal hypertension through β1 receptor blockade, which reduces cardiac output, and β2 receptor blockade, which causes splanchnic vasoconstriction. It has been postulated that β1 and β2 blockade may lead to portal vein thrombosis development by reducing portal vein inflow and portal flow velocity. [World J Gastroenterol 2014;20:11463‐11466; Expert Opin Pharmacother 2003;4:625‐637]