Np. Kumar et al., Responses to the prolonged head-up tilt followed by sublingual nitrate provocation in asymptomatic older adults, AGE AGEING, 29(5), 2000, pp. 419-424
Background: prolonged head-up tilt testing and sublingual nitrate provocati
on are increasingly used in the diagnosis of neurocardiogenic syncope. Howe
ver there are few data regarding the results of these tests in asymptomatic
older subjects.
Objective: to assess the responses to the prolonged head-up tilt test follo
wed by sublingual glyceryl trinitrate provocation in asymptomatic subjects
over the age of 60 years.
Design: observational study.
Methods: we recruited 64 asymptomatic subjects over the age of 60 (39 men,
25 women) from two general practice lists in Nottingham and Leicester. Excl
usion criteria were: history of syncope, ischaemic heart disease, cerebrova
scular disease, marked aortic stenosis, carotid artery disease and being un
able to stand for the duration of the test. hll subjects underwent a full c
linical examination, a 12-lead electrocardiogram and a 30-40-min head-up ti
lt test, during which we monitored the heart rate and blood pressure contin
uously. We ended the test prematurely if the subjects developed syncope or
symptoms of presyncope associated with hypotension with or without bradycar
dia. If they remained asymptomatic at the end of this period, they received
400 mug of sublingual glyceryl trinitrate and monitoring continued for ano
ther 15 min.
Settings: two teaching hospitals in Nottingham and Leicester.
Results: six (9%) of the subjects had a positive response (syncope or presy
ncope) to the prolonged head-up tilt test prior to glyceryl trinitrate prov
ocation. After provocation, 30 (52%) of the remaining 58 subjects had a pos
itive response.
Conclusion: the role of sublingual glyceryl trinitrate provocation followin
g prolonged head-up tilt testing in the diagnosis of neurocardiogenic (vaso
vagal) syncope in older people is questionable, as many asymptomatic older
subjects demonstrate syncopal or presyncopal symptoms.