What is the near‑syncope evaluation template (dot phrase) for assessing patients with feeling of impending loss of consciousness?

Near-Syncope Evaluation Template (Dot Phrase)

A structured near-syncope evaluation should systematically document triggers, prodromal symptoms, witness observations, recovery characteristics, orthostatic vital signs, cardiovascular examination findings, and ECG results to differentiate benign vasovagal episodes from life-threatening cardiac causes. 1, 2

Essential Historical Elements

Circumstances and Triggers

• Position at onset: Document if supine (high-risk for cardiac/arrhythmia), sitting (all causes possible), or standing (orthostatic hypotension, vasovagal) 1, 3
• Activity: During exertion (cardiac structural disease, arrhythmia, LQTS1), immediately post-exercise (post-exercise hypotension in middle-aged/elderly, vasovagal in young athletes), or at rest 1
• Specific triggers: Fear/pain/instrumentation (vasovagal), micturition/defecation (situational), eating (postprandial hypotension in elderly), head turning/neck pressure (carotid sinus), coughing (situational in smokers with lung disease) 1, 3
• Palpitations: Suggests tachyarrhythmia if present 1

Prodromal Symptoms (Onset Phase)

• Visual changes: Dark spots, loss of color vision, tunnel vision (cerebral hypoperfusion—supports syncope over seizure) 1, 4
• Auditory changes: Sounds from distance, buzzing, ringing (cerebral hypoperfusion) 1
• Autonomic symptoms: Nausea, sweating, pallor (reflex syncope/autonomic activation) 1, 3
• Pain pattern: Shoulder/neck "coat hanger" pain (orthostatic hypotension from muscle ischemia) 1
• Absence of prodrome: High-risk feature suggesting cardiac cause 2, 3

Witness Account of Event

• Duration of symptoms: <30 seconds strongly favors syncope over seizure (seizures average 74-90 seconds); >5 minutes suggests psychogenic 1
• Fall pattern: Flaccid collapse (syncope), keeling over stiff (tonic seizure or less commonly syncope) 1
• Movements: Asymmetrical/asynchronous beginning after fall onset (syncope), symmetrical/synchronous beginning before fall (seizure), few movements ~10 (syncope), many movements "cannot count" (seizure) 1
• Movement timing: Beginning 20 seconds after loss of consciousness (syncope), at onset (seizure) 1

Recovery Phase

• Speed of recovery: Rapid and spontaneous (syncope), prolonged confusion (seizure) 2
• Post-event symptoms: Fatigue common in both; tongue biting, incontinence, prolonged confusion favor seizure 1

Physical Examination Requirements

Orthostatic Vital Signs (Mandatory)

• Measurement protocol: After 5 minutes supine, then each minute standing for 3 minutes minimum 3
• Orthostatic hypotension criteria: Systolic BP drop ≥20 mmHg or drop to <90 mmHg, or diastolic drop ≥10 mmHg 3, 2, 3
• Initial orthostatic hypotension: BP drop within 15 seconds of standing 2
• Delayed orthostatic hypotension: Takes >3 minutes to develop threshold drop 2
• Orthostatic tachycardia: Heart rate increase ≥30 bpm (≥40 bpm if age 12-19) within 10 minutes of standing, often >120 bpm, without orthostatic hypotension (suggests POTS) 2

Cardiovascular Examination

• Murmurs: Assess for aortic stenosis, hypertrophic cardiomyopathy (high-risk structural disease) 3
• Irregular rhythm: Atrial fibrillation or other arrhythmias 3
• Signs of heart failure: Elevated JVP, pulmonary crackles, peripheral edema 3

Mandatory Testing

12-Lead ECG (Required in All Cases)

• Conduction abnormalities: Sinus bradycardia <40 bpm, sinus pauses >3 seconds, Mobitz II or 3rd-degree AV block, alternating bundle branch block 3
• Arrhythmias: Paroxysmal SVT, ventricular tachycardia 3
• Ischemic changes: Acute ischemia or infarction 3
• Inherited syndromes: Long QT, Brugada pattern 3, 2
• Pacemaker malfunction: Pauses in paced patients 3

Risk Stratification for Disposition

High-Risk Features Requiring Admission

• Age >60 years with first episode 2
• Known structural heart disease: Aortic stenosis, hypertrophic cardiomyopathy, heart failure, prior MI 3, 2, 3
• Abnormal ECG findings as above 3, 2, 3
• Syncope during exertion or while supine 1, 3
• Absence of prodromal symptoms 2, 3
• Family history of sudden cardiac death or inherited cardiac disease 2
• Systolic BP <90 mmHg 2
• Palpitations preceding event 1, 3

Low-Risk Features Suggesting Outpatient Management

• Age <60 years 2
• Clear vasovagal trigger: Fear, pain, prolonged standing, hot crowded places 1, 3
• Typical prodrome: Nausea, sweating, visual changes 1, 3
• Normal cardiovascular examination 3
• Normal ECG 3, 2, 3
• No known cardiac disease 3

Tests to Avoid Without Specific Indications

• Brain imaging (CT/MRI): Diagnostic yield only 0.24-1% without focal neurological findings or head trauma 4, 5, 6, 7
• EEG: Only if seizure suspected based on witness account of movements 4, 5
• Carotid ultrasound: Only if steal syndrome suspected (arm exercise trigger, BP/pulse differential between arms) 1, 4
• Comprehensive laboratory panels: Target testing based on clinical suspicion only (glucose if suspected hypoglycemia, hemoglobin if suspected anemia) 4, 5, 6

Additional Directed Testing (When Indicated)

For Suspected Cardiac Syncope

• Echocardiography: If structural heart disease suspected on exam or ECG 3, 2, 3
• Prolonged cardiac monitoring: If arrhythmia suspected but not captured on ECG 3, 2, 3
• Exercise stress testing: If syncope during or post-exertion 3, 2, 3
• Electrophysiology study: If high suspicion for arrhythmia with negative monitoring 3, 2, 3

For Suspected Neurally-Mediated Syncope

• Tilt-table testing: If recurrent vasovagal syncope despite non-pharmacological measures, or diagnosis uncertain 3, 2, 3, 5
• Carotid sinus massage: If head turning/neck pressure triggers symptoms 1, 3

Critical Documentation Pitfalls to Avoid

• Never assume benign etiology without proper cardiac evaluation, especially with structural heart disease risk factors 5, 6, 7
• Never omit orthostatic vital signs—present in 15% of cases and changes management 3, 7
• Never discharge high-risk patients without cardiac evaluation 2
• Always document medication review for drugs causing orthostatic hypotension or arrhythmias 2, 7