Endoscopic assessment of variceal volume and wall tension in cirrhotic patients: effects of pharmacological therapy

Abstract

Background & aims: Variceal rupture is believed to occur when variceal wall tension is excessive. The combined use of endosonography, allowing the objective measurement of variceal radius, and endoscopic measurement of transmural variceal pressure may enable assessment of this important parameter. The aim of this study was to assess the effects on variceal hemodynamics of drugs acting through different mechanisms: decreasing portocollateral blood flow (propranolol) or resistance (isosorbide-5-mononitrate [ISMN]).

Methods: Repeated measurements of variceal radius, volume (by endosonography), and transmural pressure (using endoscopic gauge) were performed in 27 cirrhotic patients at baseline and 40 minutes after double-blind administration of placebo (n = 9), propranolol (n = 9), or ISMN (n = 9).

Results: Placebo had no effect. Propranolol significantly reduced variceal volume (-32% +/- 26%; P = 0.01), radius (-12% +/- 9%; P < 0.005), and pressure (-26% +/- 10%; P < 0.0001). The resulting decrease in wall tension (-34% +/- 13%; P < 0.0005) exceeded that in transmural pressure (P < 0.01). ISMN reduced transmural variceal pressure (-26% +/- 21%; P < 0.005), but not radius (-3% +/-14%; NS) and volume (-9% +/- 31%; NS).

Conclusions: The combination of endosonography and endoscopic measurement of transmural variceal pressure allows quantitative estimation of variceal wall tension. Propranolol and ISMN reduce similarly transmural variceal pressure. Propranolol, but not ISMN, reduces variceal volume and radius. Therefore, despite similar decreases in variceal wall tension, propranolol may offer a greater therapeutic effect than ISMN in portal hypertension.