Evaluation and Management of Syncope

Initial Evaluation

The European Society of Cardiology recommends an initial evaluation consisting of detailed history, physical examination with orthostatic blood pressure measurements, and a 12-lead ECG, which establishes the diagnosis in 23-50% of cases and guides all subsequent testing 1, 2
Documenting the exact circumstances and characteristics of the event, including position when syncope occurred and activity at onset, is crucial for diagnosis 1
Prodromal symptoms, such as nausea, vomiting, and visual changes, should be assessed, as they can indicate the underlying cause of syncope 1, 2, 3
The American College of Cardiology suggests that precipitating factors, such as crowded or warm places, and previous episodes, should be evaluated to determine the risk of recurrence 1, 3
A family history of syncope, sudden cardiac death, or structural heart disease should be obtained, as it may indicate a genetic predisposition to syncope 3, 6
A medication review is essential to identify potential causes of syncope, such as alpha-blockers, antihypertensives, and sedatives 4, 5

Orthostatic vital signs should be measured correctly, with blood pressure and heart rate assessed after 5 minutes supine and at 1 and 3 minutes after standing 4, 5
Orthostatic hypotension is defined as a sustained drop of ≥20 mmHg systolic or ≥10 mmHg diastolic, and its presence should be evaluated 2, 4, 5
A heart rate response of <15 bpm suggests neurogenic orthostatic hypotension, while a response of ≥15 bpm suggests non-neurogenic causes 4, 5
A complete cardiovascular examination, including heart sounds, rhythm, murmurs, and peripheral pulses, should be performed to identify potential cardiac causes of syncope 3
Carotid sinus massage should be performed in patients >40 years old to evaluate for carotid sinus syndrome, which can cause up to 20% of syncope in older adults 1, 6

A 12-lead ECG should be obtained in all patients to detect conduction abnormalities, channelopathies, and signs of structural heart disease 1, 3, 4
Echocardiogram and immediate cardiac monitoring should be considered in patients with high-risk features, such as abnormal ECG or known structural heart disease 1
The European Society of Cardiology recommends that patients with syncope during exertion or while supine, or those with a family history of sudden cardiac death, should undergo further testing, including echocardiogram and cardiac monitoring 1, 6

The American College of Cardiology suggests that patients with high-risk features, such as abnormal ECG, known structural heart disease, or syncope during exertion, should be hospitalized for urgent evaluation 1, 2
Patients with low-risk features, such as clear vasovagal trigger or typical prodromal symptoms, can be safely discharged for outpatient management 3

In older adults (>65 years), orthostatic hypotension and carotid sinus syndrome are common causes of syncope, and carotid sinus massage should be performed in all patients in this age group 6
In adolescents, vasovagal syncope is the most common cause, but cardiac causes must be excluded, and a focus on identifying high-risk features is essential 3

The European Society of Cardiology recommends that patients with orthostatic hypotension should undergo medication review and lifestyle modifications, including increased fluid and salt intake, and physical counterpressure maneuvers 4, 5
Midodrine is recommended as first-line pharmacologic therapy for symptomatic orthostatic hypotension persisting despite nonpharmacologic measures 5
Patients with reflex (neurally-mediated) syncope should undergo head-up tilt testing to confirm diagnosis, particularly in patients without structural heart disease 1