TY - JOUR
T1 - Cardiovascular and Catecholamine Responses to Head‐Up Tilt in the Diagnosis of Recurrent Unexplained Syncope in Elderly Patients
AU - Hackel, Andrea
AU - Linzer, Mark
AU - Anderson, Norman
AU - Williams, Redford
PY - 1991/7
Y1 - 1991/7
N2 - To increase understanding of the mechanisms causing syncope in patients over the age of 60, hemodynamic and hormonal responses to 60 minutes of 60 degree head‐up tilt were examined in 10 patients with recurrent syncope of unknown origin and five controls with no history of syncope. Nine of 10 patients and all five controls experienced orthostatic intolerance on the tilt table. Syncope or pre‐syncope occurred later in controls than in those syncope patients who had exact reproduction of their clinical symptoms (median time 52 versus 22 minutes, P = 0.05). Three different mechanisms of orthostatic intolerance were identified in the 14 subjects: (1) vasovagal syncope, n = 9 (sudden hypotension ± bradycardia); (2) dysautonomic syncope, n = 3 (immediate and gradual parallel declines in both systolic and diastolic pressures with blunted increase in heart rate); (3) psychogenic or vestibular reaction, n = 2 (orthostatic intolerance without hemodynamic changes). Vasovagal syncope patients showed a significant increase in plasma norepinephrine from baseline to maximum level during tilt (100 ± 39% increase, P = 0.03) and a subsequent decrease at the time of syncope (30 ± 5% decrease, P = 0.01), while plasma epinephrine increased markedly from baseline to the time of syncope (827 ± 154% increase, P = 0.0003). Dysautonomy syncope patients had lower supine levels of norepinephrine compared to vasovagal syncope patients (182 ± 30 versus 614 ± 146 pg/mL, P = 0.008) and no significant change in norepinephrine over time; epinephrine levels increased significantly less than in vasovagal patients (net change 38 ± 8 versus 189 ± 56 pg/mL, P = 0.008). Psychogenic and vestibular reactions were distinguished by rising levels of norepinephrine at the time of symptoms. The 50% (5 of 10) prevalence of vasovagal reactions found in the syncope patients suggests that vasovagal syncope may be more common among the elderly than previously recognized. 1991 The American Geriatrics Society
AB - To increase understanding of the mechanisms causing syncope in patients over the age of 60, hemodynamic and hormonal responses to 60 minutes of 60 degree head‐up tilt were examined in 10 patients with recurrent syncope of unknown origin and five controls with no history of syncope. Nine of 10 patients and all five controls experienced orthostatic intolerance on the tilt table. Syncope or pre‐syncope occurred later in controls than in those syncope patients who had exact reproduction of their clinical symptoms (median time 52 versus 22 minutes, P = 0.05). Three different mechanisms of orthostatic intolerance were identified in the 14 subjects: (1) vasovagal syncope, n = 9 (sudden hypotension ± bradycardia); (2) dysautonomic syncope, n = 3 (immediate and gradual parallel declines in both systolic and diastolic pressures with blunted increase in heart rate); (3) psychogenic or vestibular reaction, n = 2 (orthostatic intolerance without hemodynamic changes). Vasovagal syncope patients showed a significant increase in plasma norepinephrine from baseline to maximum level during tilt (100 ± 39% increase, P = 0.03) and a subsequent decrease at the time of syncope (30 ± 5% decrease, P = 0.01), while plasma epinephrine increased markedly from baseline to the time of syncope (827 ± 154% increase, P = 0.0003). Dysautonomy syncope patients had lower supine levels of norepinephrine compared to vasovagal syncope patients (182 ± 30 versus 614 ± 146 pg/mL, P = 0.008) and no significant change in norepinephrine over time; epinephrine levels increased significantly less than in vasovagal patients (net change 38 ± 8 versus 189 ± 56 pg/mL, P = 0.008). Psychogenic and vestibular reactions were distinguished by rising levels of norepinephrine at the time of symptoms. The 50% (5 of 10) prevalence of vasovagal reactions found in the syncope patients suggests that vasovagal syncope may be more common among the elderly than previously recognized. 1991 The American Geriatrics Society
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U2 - 10.1111/j.1532-5415.1991.tb03619.x
DO - 10.1111/j.1532-5415.1991.tb03619.x
M3 - Article
C2 - 2061531
AN - SCOPUS:0025861603
SN - 0002-8614
VL - 39
SP - 663
EP - 669
JO - Journal of the American Geriatrics Society
JF - Journal of the American Geriatrics Society
IS - 7
ER -