Syncope

CLINICAL DIAGNOSTIC MANUAL

Syncope is a transient and sudden loss of consciousness, usually caused by a temporary reduction in cerebral blood flow. This condition typically resolves spontaneously with rapid and complete recovery.

Syncope can result from various conditions, ranging from benign to potentially life-threatening, and may be due to cardiovascular, neurological, or metabolic disorders. It is crucial to differentiate syncope from other causes of loss of consciousness, such as seizures or strokes, to ensure appropriate management.

Pathology	Clinical Symptoms and Signs	Suspected Diagnosis	Confirmatory Diagnosis
Vasovagal syncope	Dizziness, nausea, sweating, pallor before the episode, triggered by emotions or pain.	Clinical history of recurrent episodes, triggering factors.	Confirmation with tilt-table test.
Cardiac arrhythmias	Sudden loss of consciousness, prior palpitations or bradycardia, rapid recovery.	History of palpitations or abnormal heart rhythms. Abnormal ECG.	Confirmation with ECG or Holter monitoring.
Orthostatic hypotension	Syncope upon standing, dizziness, blurred vision, triggered by postural changes.	Clinical history of episodes with positional changes. Blood pressure measurement.	Confirmation with blood pressure measurement in standing and supine positions.
Aortic stenosis	Syncope associated with physical exertion, dyspnoea, chest pain, systolic murmur.	History of syncope during exercise, physical examination with cardiac murmur.	Confirmation with echocardiogram.
Acute myocardial infarction	Severe chest pain, dyspnoea, syncope, profuse sweating, pallor.	Clinical history of acute chest pain, cardiovascular risk factors.	Confirmation with ECG, troponins, and echocardiogram.
Hypoglycaemia	Sweating, confusion, blurred vision, syncope, recovery after sugar intake.	History of diabetes or previous hypoglycaemic episodes.	Confirmation with low blood glucose levels during the episode.
Pulmonary embolism	Sudden syncope, dyspnoea, pleuritic chest pain, tachypnoea, haemoptysis.	History of thromboembolic risk factors (immobility, surgery).	Confirmation with CT pulmonary angiography or lung scan.
Hypertrophic cardiomyopathy	Syncope during exercise, dyspnoea, palpitations, family history of sudden death.	Physical examination with cardiac murmur.	Confirmation with echocardiogram or cardiac MRI.
Seizures	Tonic-clonic movements, prolonged loss of consciousness, postictal confusion.	History of abnormal movements during the episode.	Confirmation with electroencephalogram (EEG).