Contribution of cardiovascular hypersensitivity to orthostatic hypertension and the extreme dipper phenomenon.
We report the case of a 68-yr-old woman who, upon standing, experienced dizziness in association with increased blood pressure (BP) and heart rate (HR). We made a diagnosis of orthostatic hypertension and examined the BP response to postural change using the head-up tilt test. Positional change resulted in a 20-mmHg increase in systolic BP and a 15-bpm increase in HR. A 24-h ambulatory BP recording showed daytime hypertension that decreased at night, along with a nocturnal decrease in HR. Based on these post-diagnostic results, the patient was rediagnosed as an extreme dipper with silent lacunar infarction as the only complication of orthostatic hypertension. We suggest that, in our patient, the mechanism of orthostatic hypertension was hypersensitivity of cardiovascular responsiveness to endogenous vasoconstrictors. This was evidenced by increased pressure sensitivity to isoproterenol as well as phenylephrine. We thus selected carvedilol, a beta-blocker with slight alpha-blocking action, and were more effective in abolishing the hypertension.
Moriguchi
A
A
Department of Geriatric Medicine, Osaka University Medical School, Suita, Japan.
Nakagami
H
H
Kotani
N
N
Higaki
J
J
Ogihara
T
T
D000316:Adrenergic alpha-Agonists; D000318:Adrenergic beta-Agonists / Q000627:therapeutic use; D000368:Aged; D000959:Antihypertensive Agents / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D018660:Blood Pressure Monitoring, Ambulatory; D002227:Carbazoles / Q000627:therapeutic use; D002319:Cardiovascular System / Q000503:physiopathology*; D000077261:Carvedilol; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000503:physiopathology*; D007545:Isoproterenol; D009638:Norepinephrine; D010656:Phenylephrine; D011187:Posture / Q000502:physiology*; D011412:Propanolamines / Q000627:therapeutic use; D013599:Systole; D018667:Tilt-Table Test
D000316:Adrenergic alpha-Agonists; D000318:Adrenergic beta-Agonists; D000959:Antihypertensive Agents; D002227:Carbazoles; D011412:Propanolamines; D000077261:Carvedilol; D010656:Phenylephrine; D007545:Isoproterenol; D009638:Norepinephrine