A frail 80-year-old nursing home resident has had several episodes of syncope, all of which have occurred while she was returning to her room after breakfast. She complains of light-headedness and states she feels cold and weak. She takes nitroglycerin in the morning for a history of chest pain, but denies recent chest pain or shortness of breath.
Which of the following is the best initial test?
A. Carotid Doppler ultrasoundPostprandial hypotension has been increasingly recognized in the frail elderly. In one study, a quarter of all patients had a reduction in systolic blood pressure of greater than 20 mm Hg. Much of the decrease is attributed to splanchnic blood pooling. Those on nitrates and other drugs that cause postural hypotension are at greatest risk. Older patients with this condition should avoid large meals. Diagnosis is confirmed by monitoring blood pressure after eating. Carotid studies are indicated in those with focal weakness/numbness or amaurosis fugax suggestive of focal carotid disease; this woman’s symptoms instead suggest global brain underperfusion. Cardiac arrhythmia is unlikely to cause the symptoms described. Arrhythmic symptoms are usually of sudden onset and are typically not preceded by warning symptoms such as coldness and light-headedness. If initial evaluation is negative a Holter monitor may be of value. CT scan is rarely helpful in the evaluation of syncope in a patient without focal neurologic findings. In the absence of clinical features to suggest seizure, EEG is not recommended in the diagnostic workup of syncope.