From:  Diagnostic performance of artificial intelligence in the syncope unit

 Risk-stratification in the syncope unit.

CategoryRisk LevelFeatureTotal per itemTotal per group
Syncopal eventLow-riskAssociated with prodrome typical of reflex syncope (e.g. light-headedness, feeling of warmth, sweating, nausea, vomiting)2776
Low-riskAfter sudden unexpected unpleasant sight, sound, smell, or pain7
Low-riskAfter prolonged standing or crowded, hot places11
Low-riskDuring a meal or postprandial3
Low-riskTriggered by cough, defaecation, or micturition8
Low-riskWith head rotation or pressure on carotid sinus (e.g. tumour, shaving, tight collars)1
Low-riskStanding from supine/sitting position19
High-risk (Minor)No warning symptoms or short (< 10 seconds) prodrome3148
High-risk (Minor)Family history of Sudden Cardiac Death at young age6
High-risk (Minor)Syncope in the sitting position11
High-risk (Major)New onset of chest discomfort, breathlessness, abdominal pain, or headache114
High-risk (Major)Syncope during exertion or when supine11
High-risk (Major)Sudden onset palpitation immediately followed by syncope2
Past medical historyLow-riskLong history (years) of recurrent syncope with low-risk features with the same characteristics of the current episode1460
Low-riskAbsence of structural heart disease46
High-risk (Major)Severe structural or coronary artery disease (heart failure, low Left Ventricular Ejection Fraction or previous myocardial infarction)66
Physical examinationLow-riskNormal examination4545
High-risk (Major)Unexplained systolic blood pressure in the emergency department < 90 mmHg010
High-risk (Major)Suggestion of gastrointestinal bleed on rectal examination0
High-risk (Major)Persistent bradycardia (< 40 b.p.m.) in awake state and in absence of physical training0
High-risk (Major)Undiagnosed systolic murmur10
ElectrocardiogramLow-riskNormal electrocardiogram4343
High-risk (Minor)Mobitz I second-degree Atrioventricular block block and 1°degree Atrioventricular block with markedly prolonged PR interval03
High-risk (Minor)Asymptomatic inappropriate mild sinus bradycardia (40–50 b.p.m.), or slow atrial fibrillation (40–50 b.p.m.)1
High-risk (Minor)Paroxysmal Supraventricular Tachycardia or Atrial Fibrillation1
High-risk (Minor)Pre-excited QRS complex0
High-risk (Minor)Short QTc interval (≤ 340 ms)0
High-risk (Minor)Atypical Brugada patterns1
High-risk (Minor)Negative T waves in right precordial leads, epsilon waves suggestive of arrhythmogenic right ventricular cardiomyopathy0
High-risk (Major)Electrocardiogram changes consistent with acute ischaemia010
High-risk (Major)Mobitz II second- and third-degree Atrioventricular block0
High-risk (Major)Slow Atrial Fibrillation (< 40 b.p.m.)0
High-risk (Major)Persistent sinus bradycardia (< 40 b.p.m.), or repetitive sinoatrial block or sinus pauses >3 seconds in awake state and in absence of physical training0
High-risk (Major)Bundle branch block, intraventricular conduction disturbance, ventricular hypertrophy, or Q waves consistent with ischaemic heart disease or cardiomyopathy10
High-risk (Major)Sustained and non-sustained ventricular tachycardia0
High-risk (Major)Dysfunction of an implantable cardiac device (pacemaker or Implantable Cardioverter-Defibrillator)0
High-risk (Major)Type I Brugada pattern0
High-risk (Major)ST-segment elevation with type I morphology in leads V1–V3 (Brugada pattern)0
High-risk (Major)QTc > 460 ms in repeated 12-lead electrocardiogram indicating LQTS0

Guideline-based risk-stratification features per category (syncopal event, medical history, physical examination, and electrocardiogram). Totals are shown per feature and summed per risk-group. High-risk (minor) features were interpreted according to the conditional ESC criteria. Minor high-risk features related to the syncopal event were considered high-risk only when associated with structural heart disease and/or an abnormal electrocardiogram. Minor high-risk electrocardiographic features were considered high-risk only when the clinical history was consistent with arrhythmic syncope. Adapted with permission from [1]. © The European Society of Cardiology 2018.