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NASA NTRS · 20040172858

Malignant vagotonia due to selective baroreflex failure

Jordan, J.·Shannon, J. R.·Black, B. K.·Costa, F.·Ertl, A. C.·Furlan, R.·Biaggioni, I.·Robertson, D.
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Abstract

Baroreflex failure is characterized by dramatic fluctuations of sympathetic activity and paroxysms of hypertension and tachycardia. In contrast, unopposed parasympathetic activity has not been described in patients with baroreflex failure because of concurrent parasympathetic denervation of the heart. We describe the unusual case of a patient with baroreflex failure in a setting of preserved parasympathetic control of HR manifesting episodes of severe bradycardia and asystole. Thus, parasympathetic control of the HR may be intact in occasional patients with baroreflex failure. Patients with this selective baroreflex failure require a unique therapeutic strategy for the control of disease manifestations.

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Case ReportsNon-NASA CenterNASA Discipline Regulatory PhysiologyBaroreflex/physiologyVagus Nerve/physiopathologyFemaleHypotension/etiology/physiopathologyStimulation, ChemicalValsalva Maneuver/physiologySupport, U.S. Gov't, Non-P.H.SBradycardia/etiology/physiopathologyHead-Down Tilt/physiologyParasympathetic Nervous System/physiopathologyNorepinephrine/bloodHeart Rate/physiologyBlood Pressure/physiologySupine Position/physiologySupport, U.S. Gov't, P.H.SSupport, Non-U.S. Gov'tNervous System Diseases/etiology/physiopathologyHumanMiddle Aged

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Jordan, J., Shannon, J. R., Black, B. K., Costa, F., Ertl, A. C., Furlan, R., Biaggioni, I., Robertson, D.. 1997-11-01. Malignant vagotonia due to selective baroreflex failure. https://ntrs.nasa.gov/citations/20040172858

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