Posture- and emotion-induced severe hypertensive paroxysms with baroreceptor dysfunction.

In a patient followed up for 30 years, severe but brief posture- or emotion-induced hypertensive paroxysms with flushing were associated with an increased cardiac output [inconsistently accompanied by increased plasma catecholamines (CA)] and a decreased blood pressure reactivity to norepinephrine with decreased reflex bradycardia. Sodium depletion further accentuated the latter abnormality and reproducibly reversed orthostatic hypertension to orthostatic hypotension. Abnormal responses in the Valsalva manoeuvre in an upright position suggested a defect in baroreceptor sensitivity, but may also have been due to an impaired venous return. The indices of the efferent portion of the reflex and central nervous system responses to stimuli were normal or exaggerated. The abnormality was probably due to a hypothalamic dysfunction and/or an abnormal central baroreceptor integration in the nucleus tractus solitarii. The absence of left ventricular hypertrophy and other target lesions, despite spectacular rises in blood pressure, suggests an excellent cardiovascular tolerance of hypertensive episodes if they are short-lived.