EVALUATION OF AUTONOMIC FUNCTION AND BAROREFLEX SENSITIVITY IN CIRRHOTIC-PATIENTS WITH PORTAL-HYPERTENSION

Hyperdynamic circulatory disturbances associated with reduced peripher al resistance, splachnic vasodilatation and increased cardiac output a re described in portal hypertensive patients. The baroreflex system, p henylephrine reactivity, Valsalva manoeuvre, heart rate response to de ep breathing and the upright position test were evaluated in seven por tal hypertensive cirrhotic subject and in seven healthy volunteers. Po rtal hypertensive patients showed normal values of systemic blood pres sure and heart rate, and a diminished presser response to phenylephrin e. The baroreceptor reflex sensitivity was significantly decreased. Th e Valsalva ratio as well as deep breathing were impaired in this patho logy. We found no changes during a tilting test in these patients. The present study shows that in cirrhotic patients with portal hypertensi on, vascular responsiveness is altered, indicating a resetting in baro receptor reflex function. The dysfunction observed in the autonomic pa rasympathetic system may be involved in the haemodynamic disturbances described.