Impaired Cardiovascular Autonomic Response to Passive Tilting in Cirrhosis With Ascites

Abstract

The autonomic regulation of cardiovascular function was evaluated in 15 cirrhotic patients with ascites and in 13 healthy subjects by the autoregressive power spectral analysis (PSA) of the intervals between adjacent R waves of the electrocardiogram (RR) interval and arterial pressure variability. Total power, low frequency (LF; index of the sympathetic activity of the heart and circulation), and high frequency (HF; index of vagal tone to the heart) components of the RR interval, systolic, and diastolic arterial pressure were evaluated in the supine position and during passive tilting, together with plasma norepinephrine levels. In the supine position, no significant differences in the PSA data were observed between the control subjects and cirrhotic patients, who had higher plasma norepinephrine levels. In healthy subjects, tilting was associated with an increase in the LF of the RR interval and arterial pressure and a decrease in the HF of the RR interval. In contrast, patients with cirrhosis showed a decrease of both LF and HF. Consequently, the LF/HF ratio significantly increased in healthy subjects, whereas it was unchanged in cirrhotic patients. The LF component of the diastolic pressure also decreased during tilting in cirrhotic patients. Plasma norepinephrine increased after tilting in both groups. These results indicate that the autonomic response to passive tilting is impaired in cirrhotic patients with ascites at both the cardiac and vascular levels, as a result of an altered sympatho-vagal balance, with reduced sympathetic predominance. These alterations occurred despite an appropriate response to the tilting of plasma norepinephrine, pointing to a receptorial or postreceptorial site of the autonomic impairment.

Impaired sympathetic regulation of cerebral blood flow in patients with cirrhosis of the liver

“…In RR-interval analysis, cirrhotic patients had significantly lower increments in LF power and the LF\HF ratio than control subjects [39,40]. The same pattern of impaired sympathetic activation has been observed previously in patients with ascites, in response to head-up tilt [11]. Data on RR interval therefore confirm the impaired autonomic regulation reported in previous investigations [5][6][7][8][9][10][11] with more confidence, since neck chamber suction made sure of reduced interference.…”

“…These results indicate that patients with cirrhosis have an altered sympathetic regulation of the cerebral circulation that is characterized by an inadequate response of resistance microvessels, despite adequate baroreceptor function. methodology, we have shown that the autonomic response to passive tilting is impaired in patients suffering from cirrhosis with ascites [11].…”

The Relationship of Heart Rate Variability with Severity and Prognosis of Cirrhosis

“…Disparate events may contribute to the development of autonomic neuropathy and reduced HRV, including factors affecting nerve integrity, such as alterations in lipid metabolism, vitamin E deficiency, alcohol intake, immunologic mechanisms, and retention of toxic metabolites [11,13]. Moreover, vagal function may be inhibited by elevated angiotensin II production [21] and the sympathetic function may be impaired by blunted end-organ responsiveness [7,11] owing to either production of weak neurotransmitters [22] or a receptorial and postreceptorial defect [10,23]. In addition to these factors, vasodilating substances must be taken into account.…”

“…Cirrhosis, both alcoholic and nonalcoholic, has been reported to be associated with autonomic neuropathy, as well as other hemodynamic and circulatory disturbances [1][2][3][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. It has also been reported that the prevalence of autonomic neuropathy is proportional to the severity of cirrhosis [3,8,9], and its presence is an indicator of poor prognosis in patients with both early and advanced liver cirrhosis [3,12,13].…”

Spontaneous baroreflex cardiac sensitivity in end-stage liver disease

“…Whatever the mechanism, this arterial vasodilatation brings into play the autonomic nervous system, which may contribute to the maintenance or the amplification of the circulatory alteration. During the course of the chronic liver disease, several studies have documented a decrease in the vagal activity along with an increased sympathetic activity [5][6][7][8], this autonomic nervous system imbalance being an independent predictor of mortality [6]. This may be a further concern for anaesthesiologists knowing the circulatory instability during the anaesthesia of patients with autonomic nervous system imbalance [9].…”