Responses to the prolonged head-up tilt followed by sublingual nitrate provocation in asymptomatic older adults

64 asymptomatic adults over the age of 60 (39 men, 25 women). Exclusion criteria: history of syncope, ischaemic heart disease, cerebrovascular disease, marked aortic stenosis, carotid artery disease, and being unable to stand for the duration of the test.

30-40-minute head-up tilt test followed by 400 microg of sublingual glyceryl trinitrate provocation (if asymptomatic after initial tilt) with an additional 15 minutes of monitoring.

Positive response (syncope or symptoms of presyncope associated with hypotension with or without bradycardia) during the test.surrogate