Noninvasive assessment of spontaneous baroreflex sensitivity in patients with liver cirrhosis

Aims/Background: An impairment of baroreceptor sensitivity has been found i n liver cirrhosis. Noninvasive and spontaneous estimates of baroreflex sens itivity are obtained from beat-to-beat blood pressure and heart rate record ings by means of cross-spectrum analysis and calculation of alpha-index las a measure of baroreflex gain). The aim of the present study was to investi gate the function of the spontaneous baroreflex sensitivity related to clin ical Child score in liver cirrhosis. Methods: The alpha-index was evaluated in 40 cirrhotic patients (18 with and 22 without ascites) and 17 healthy s ubjects by analysing finger arterial pressure recorded noninvasively with t he Portapres device. Results. Baroreflex sensitivity was significantly lowe r in cirrhotic patients with and without ascites compared with healthy subj ects (p<0.01). Furthermore, in patients with ascites the baroreflex gain wa s significantly related to plasma sodium (p<0.01). A significant inverse re lationship was present between baroreflex gain and grade of Child score and the severity of ascites (p<0.01). There were no significant relationships between hormonal parameters (catecholamines, renin, aldosterone, arginine-v asopressin, atrial natriuretic peptide and nitric oxide) and baroreflex gai n. No significant differences were found between healthy subjects and cirrh otic patients with respect to systolic and diastolic blood pressure total v ariability in a supine position, whilst it was lower in cirrhotic patients with ascites in a tilted position (p<0.05). Conclusion: Our findings showed that baroreflex sensitivity was significantly impaired in cirrhotic patien ts when compared with healthy subjects. In addition, there was a significan t trend toward lower baroreflex sensitivity values with the grade score of Child class (p<0.01). Spectral analysis of the alpha-index provides viable alternatives to the pharmacological approach for estimation of baroreflex s ensitivity and may represent a prognostic tool to identify cirrhotic patien ts at increased risk of adverse events.