[Abnormalities of cardiovascular baroreflex control in renal failure and cardiac insufficiency. Experimental study and brief critical review of the literature].

We attempted to determine the relevance and relative prevalence of autonomic dysfunction in 7 patients with end-stage renal disease (ESRD) but no heart disease, 8 patients with left ventricular dysfunction (LVD) with no renal disease and 8 patients with ESRD + LVD. In each group, the assessment of autonomic function and location of the lesion was performed by using the baroreflex sensitivity tests, based upon heart rate (ie Valsalva, deep breathing, lying to standing) to study the parasympathetic system as well as based upon blood arterial pressure (ie standing and sustained handgrip) to evaluate the sympathetic system. The same tests were performed in 7 healthy volunteers enrolled as control group. Separate studies were performed on the efferent parasympathetic arc (atropine test) and the efferent sympathetic arc (cold pressor test). There was evidence of parasympathetic damage in 100% of ESRD patients, in 87.5% of ESRD + LVD patients, and in 62.5% of LVD. Only 1 of ESRD patients showed defective response to atropine whereas the remaining had a normal response, suggesting an afferent lesion alone. No abnormalities were found in the response to cold pressor test, thereby suggesting a lack of involvement of the efferent sympathetic arc. The response to handgrip was higher in LVD patients.(ABSTRACT TRUNCATED AT 250 WORDS)