Syncope

Confirm that the event was transient loss of consciousness with rapid onset, short duration, and spontaneous complete recovery before applying a syncope pathway. Generalized epileptic seizure, functional transient loss of consciousness, acute blood loss, intoxication, concussion, subarachnoid hemorrhage, pulmonary embolism, aortic dissection, ruptured ectopic pregnancy, and other disorders can mimic syncope or coexist with it. Nature+2NatureA guide to disorders causing transient loss of consciousness: focus on syncope | Nature Reviews NeurologyScienceDirectVascular Causes of Syncope: An Emergency Medicine Review - ScienceDirectPubMedVasovagal Episode - StatPearls - NCBI Bookshelf

Immediately assess airway, breathing, circulation, injury, persistent altered mental status, active bleeding, chest pain, dyspnea, focal neurologic findings, and hemodynamic instability. These findings redirect care toward the suspected emergency rather than outpatient syncope testing; vascular and obstructive causes requiring consideration include pulmonary embolism, aortic dissection, intracranial hemorrhage, carotid or vertebral dissection, and abdominal aortic aneurysm. ScienceDirect+1ScienceDirectVascular Causes of Syncope: An Emergency Medicine Review - ScienceDirectPubMedVasovagal Episode - StatPearls - NCBI Bookshelf

Treat a presentation as potentially cardiac when syncope occurs during exertion or while supine, is accompanied by palpitations, or occurs in a patient with heart failure, prior myocardial infarction, left-ventricular dysfunction, severe structural heart disease, or abnormal ECG findings. Obtain monitored evaluation and targeted testing for arrhythmia, ischemia, or structural disease in this branch. jaccjaccSyncope: Therapeutic Approaches

Admit patients with a serious suspected underlying condition; patients with clearly low-risk features may be managed as outpatients, whereas intermediate-risk patients are candidates for emergency-department observation or a dedicated syncope unit when available. PubMedPubMedEvaluation and Management of Syncope: Comparing the Guidelines of the American College of Cardiology/American Heart Association/Heart Rhythm Society and the European Society of Cardiology

Obtain a detailed event history from the patient and witnesses, including posture, exertion, situational trigger, prodrome, palpitations, duration of unresponsiveness, recovery, injury, medication exposure, prior events, cardiovascular history, and family history. A detailed history, physical examination, family history, and 12-lead ECG are recommended for syncope evaluation; in older adults, polypharmacy, autonomic dysfunction, orthostatic intolerance, and carotid sinus hypersensitivity frequently contribute simultaneously. jacc+1jacc2017 ACC/AHA/HRS Guideline for the Evaluation and Management of Patients With Syncope: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm SocietyjaccAHA/ACCF Scientific Statement on the Evaluation of Syncope: From the American Heart Association Councils on Clinical Cardiology, Cardiovascular Nursing, Cardiovascular Disease in the Young, and Stroke, and the Quality of Care and Outcomes Research Interdisciplinary Working Group; and the American College of Cardiology Foundation In Collaboration With the Heart Rhythm Society

Measure supine and standing blood pressure and heart rate. A reproducible orthostatic pattern shifts management toward volume status, medication effects, autonomic dysfunction, and orthostatic hypotension; when bedside assessment is nondiagnostic but delayed orthostatic hypotension remains suspected, tilt-table testing can be useful. jacc+1jaccAHA/ACCF Scientific Statement on the Evaluation of Syncope: From the American Heart Association Councils on Clinical Cardiology, Cardiovascular Nursing, Cardiovascular Disease in the Young, and Stroke, and the Quality of Care and Outcomes Research Interdisciplinary Working Group; and the American College of Cardiology Foundation In Collaboration With the Heart Rhythm Societyjacc2017 ACC/AHA/HRS Guideline for the Evaluation and Management of Patients With Syncope: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society

Perform a 12-lead ECG in every patient and use it to direct further testing rather than as a stand-alone exclusion test. ECG and echocardiography can identify clues such as left-ventricular dysfunction, dynamic ventricular outflow obstruction, atrial myxoma or thrombus, and ECG abnormalities that indicate a cardiac pathway. jaccjaccSyncope: Therapeutic Approaches

Order CBC, electrolytes, cardiac biomarkers, imaging, or other studies only when the history, examination, or ECG suggests a specific competing diagnosis. In a healthy patient with classic vasovagal syncope, normal examination, and normal ECG, laboratory testing is low yield and no further testing is indicated. PubMedPubMedVasovagal Episode - StatPearls - NCBI Bookshelf

For recurrent or unexplained syncope with possible arrhythmia, pursue ambulatory ECG monitoring to document symptom-rhythm correlation. Long-term monitoring is often warranted when initial findings do not establish a diagnosis; in persistent unexplained syncope, extended rhythm monitoring may be used as appropriate, although an optimal device and monitoring duration are not firmly established. jacc+1jaccSyncope: Therapeutic Approachesjacc2017 ACC/AHA/HRS Guideline for the Evaluation and Management of Patients With Syncope: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society

Use echocardiography when history, examination, or ECG raises concern for structural heart disease. In athletes with unexplained exertional syncope after an initial cardiovascular evaluation, extended monitoring can be beneficial; exercise stress testing, echocardiography, and cardiac MRI are selected according to the suspected cardiovascular substrate. jaccjacc2017 ACC/AHA/HRS Guideline for the Evaluation and Management of Patients With Syncope: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society

Tilt-table testing is not a screening test for all unexplained events. It is useful after nondiagnostic initial evaluation when vasovagal syncope or delayed orthostatic hypotension is suspected, and it is reasonable in selected patients to distinguish convulsive syncope from epilepsy or diagnose pseudosyncope. It should not be used to predict response to vasovagal drug therapy. jaccjacc2017 ACC/AHA/HRS Guideline for the Evaluation and Management of Patients With Syncope: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society

Consider electrophysiologic study only in selected patients with suspected arrhythmic syncope. EPS is not recommended when ECG and structure are normal unless a specific arrhythmic concern remains; a nondiagnostic initial evaluation does not itself justify invasive testing. jaccjacc2017 ACC/AHA/HRS Guideline for the Evaluation and Management of Patients With Syncope: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society

For vasovagal syncope, provide education regarding symptom awareness and trigger avoidance. Patients with a recognizable prodrome should sit or lie supine when symptoms begin; increase fluid and salt intake when clinically appropriate, avoid dehydration, and use physical countermeasures when a sufficiently long prodrome permits. PubMed+2PubMedEvaluation and Management of Syncope: Comparing the Guidelines of the American College of Cardiology/American Heart Association/Heart Rhythm Society and the European Society of CardiologyPubMedSyncope - StatPearls - NCBI Bookshelf - NIHPubMedVasovagal Episode - StatPearls - NCBI Bookshelf

For recurrent vasovagal episodes despite avoidance of triggers and conservative measures, midodrine may be useful. Orthostatic training or fludrocortisone may be considered, and beta-blockers may be considered in patients older than 42 years; tilt-table response should not be used to predict medication benefit. PubMed+1PubMedEvaluation and Management of Syncope: Comparing the Guidelines of the American College of Cardiology/American Heart Association/Heart Rhythm Society and the European Society of Cardiologyjacc2017 ACC/AHA/HRS Guideline for the Evaluation and Management of Patients With Syncope: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society

For orthostatic syncope, identify and reverse exacerbating factors, including dehydration and medication burden. In older adults, address polypharmacy, autonomic dysfunction, orthostatic intolerance, and carotid sinus hypersensitivity concurrently rather than attributing events to one finding without reassessment. jacc+1jaccAHA/ACCF Scientific Statement on the Evaluation of Syncope: From the American Heart Association Councils on Clinical Cardiology, Cardiovascular Nursing, Cardiovascular Disease in the Young, and Stroke, and the Quality of Care and Outcomes Research Interdisciplinary Working Group; and the American College of Cardiology Foundation In Collaboration With the Heart Rhythm SocietyPubMedSyncope - StatPearls - NCBI Bookshelf - NIH

For cardiac syncope, definitive therapy depends on the documented rhythm disorder or structural substrate. When an arrhythmic cause is suspected but unproven, prioritize rhythm correlation with monitoring; when structural disease, ischemia, cardiomyopathy, or pulmonary hypertension is suspected, direct treatment to that disease process after targeted imaging and cardiovascular evaluation. jacc+1jaccSyncope: Therapeutic ApproachesScienceDirectSyncope - ScienceDirect

Arrange follow-up according to the unresolved diagnostic question: cardiovascular follow-up for abnormal ECG, structural disease, exertional or supine events, palpitations, or recurrent unexplained episodes; neurologic evaluation when seizure or other neurologic pathology remains plausible; and medication/autonomic review for orthostatic presentations. jacc+3jaccSyncope: Therapeutic Approachesjacc2017 ACC/AHA/HRS Guideline for the Evaluation and Management of Patients With Syncope: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm SocietyjaccAHA/ACCF Scientific Statement on the Evaluation of Syncope: From the American Heart Association Councils on Clinical Cardiology, Cardiovascular Nursing, Cardiovascular Disease in the Young, and Stroke, and the Quality of Care and Outcomes Research Interdisciplinary Working Group; and the American College of Cardiology Foundation In Collaboration With the Heart Rhythm SocietyNatureA guide to disorders causing transient loss of consciousness: focus on syncope | Nature Reviews Neurology

At follow-up, document recurrence frequency, posture and triggers, prodrome, injury, medication changes, orthostatic measurements, ECG findings, and any monitor-recorded symptoms. Escalate from short-term to extended ECG monitoring when intermittent arrhythmia remains plausible and initial monitoring has not captured an event. jacc+1jaccSyncope: Therapeutic Approachesjacc2017 ACC/AHA/HRS Guideline for the Evaluation and Management of Patients With Syncope: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society

Avoid routine monitoring in low-risk patients whose emergency assessment establishes a benign reflex diagnosis. In contrast, low-risk patients with a negative initial emergency workup generally do not need ambulatory monitoring, although it may be considered for reassurance in selected patients; this tradeoff should not delay targeted evaluation in patients with cardiac-risk features. PubMedPubMedSyncope: a review of emergency department management ...