Syncope and Collapse: Symptoms, Complaints, Signs

The following symptoms and complaints may indicate syncope:

Leading symptom

  • Short-term loss of consciousness with/without falling down.

Note: typical triggers, prodromes (uncharacteristic precursors or even early symptoms of a disease), brief reorientation

Canadian syncope risk score

Factors Points
Predisposition to vasovagal symptoms* . -1
Known heart disease* * 1
Any systolic value < 90 or > 180 mmHg. 2
Elevated troponin levels (> 99th percentile of the general population) 2
Abnormal QRS axis (< -30° or > 100°). 1
QRS time > 130 ms 1
Corrected QT interval > 480 ms 2
Diagnosis of vasovagal syncope -2
Diagnosis of cardiac syncope 2
Total score (-3 to 11)

* Triggers include warm, confined spaces, prolonged standing, anxiety, strong emotions, or pain.

* * These include heart failure, CHD, valvular heart disease, non-sinus rhythm.

Risk Assessment

Total score 30-day risk of serious events (%). Risk category
-3 0,4 very low
-2 0,7 very low
-1 1,2 low
0 1,9 low
1 3,1 moderate
2 5,1 moderate
3 8,1 moderate
4 12,9 high
5 19,7 high
6 28,9 very high
7 40,3 very high
8 52,8 very high
9 65,0 very high
10 75,5 very high
11 86,3 very high

Clinical signs and symptoms indicative of the diagnosis of cardiac syncope:

  • Age ≥ 35 years [specificity 91%] [sensitivity 91%].
  • Atrial fibrillation/flutter
  • Structural heart disease or coronary artery disease (CAD; coronary artery disease).
  • History of heart failure (cardiac insufficiency).
  • Cyanosis (bluish discoloration of the skin or mucous membranes) during fainting (observed by witnesses)

Other indications

  • Medical history: sudden cardiac death at a young age or in close relatives.
  • Syncope during physical exertion or while lying down
  • Palpitations* immediately preceding syncope.

* Cardiac actions perceived by the affected person himself as unusually rapid, vigorous, or irregular.

Warning signs (red flags)

  • Immediate hospitalization with ECG monitoring and prompt cardiologic evaluation is required for the following high-risk constellations [Guidelines: Brignole M et al : 2018 ESC Guidelines]:

    • New-onset chest, abdominal, or head pain or dyspnea (shortness of breath).
    • Sudden palpitations immediately preceding fainting
    • Known heart failure, low ejection fraction, or previous myocardial infarction (heart attack)
    • Syncope during exercise or supine when no vasovagal triggers are apparent.
    • Unexplained systolic blood pressure < 90 mmHg.
    • Persistent bradycardia < 40 bpm while awake (non-athlete).
    • Previously unknown systolic murmur
    • ECG findings suggesting a rhythmogenic cause.
    • Pronounced anemia (anemia) or electrolyte disturbance (disturbance of blood salts).
  • A harmless circulatory reaction cannot be assumed if the following indications or diseases are present in the anamnesis (medical history):
  • Young patients are more likely to have a vasovagal reaction (circulatory collapse).
  • In middle-aged patients, it is more likely to be a cardiac arrhythmia or transient ischemic attack (TIA; sudden circulatory disturbance of the brain leading to neurologic dysfunction that resolves within 24 hours).
  • In case of syncope + chest pain (chest pain) → think of: Myocardial infarction
  • In case of syncope, always also think of severe internal bleeding (e.g. gastrointestinal bleeding/gastrointestinal bleeding).
  • If the patient looks dead and has a striking facial flushing on recovery, this is an indication of an Adams-Stokes seizure (information on the course should be obtained via an observer/those present).
  • The finding of an aortic murmur should be cause for immediate hospitalization. Aortic stenosis (valvular defect in which the outflow tract of the left ventricle is narrowed) can lead to sudden cardiac death.
  • Twitching to bilateral symmetric myoclonia (rapid involuntary muscle twitching; signs of grand mal seizure) → think of:
    • Hyperventilation syndrome (increased breathing beyond what is needed); symptoms: e.g., muscle spasms, paresthesias (false sensations), pawing of the hands
    • Syncope (see above ): pale patient, reoriented after a few seconds; reports trigger more frequently; states blackness before eyes; may have bilateral tinnitus (bilateral ringing in ears); tonic phase is low; myoclonias are brief, arrhythmic, and multifocal
    • Epilepsy (seizure); cyanotic patient who often requires 5-45 minutes to reorient after a grand mal seizure; postictal: tongue biting (about 30%), wetting (about 20%), headache (about 40%); triggers rare; tonic phase is marked; myoclonias are violent, rhythmic, and symmetrical