Diapositiva PPT
Pérdida transitoria de consciencia
Ataques no sincopales (16%)
Con pérdida de conciencia real (crisis comicial, TIA, etc)
Sin real pérdida de conciencia (psicológico “síncope”, etc)
Enfermedad estructural cardiopulmonar
Notes:
DIFERENCIAR QUE es y que no es!!!
Syncope must be differentiated from other “non-syncopal” conditions which also lead to transient loss of consciousness.
The subdivision of syncope is based on pathophysiology as follows:
- “Neurally-mediated reflex syncopal syndrome” refers to a reflex that, when triggered, gives rise to vasodilatation and bradycardia, although the contribution of both to systemic hypotension and cerebral hypoperfusion may differ considerably.
- ‘Orthostatic’ syncope occurs when the autonomic nervous system is incapacitated resulting in a failure of vasoconstrictor mechanisms and thereby in orthostatic hypotension; ‘Volume depletion’ is another important cause of orthostatic hypotension and syncope
- ‘Cardiac arrhythmias’ can cause a decrease in cardiac output, which usually occurs irrespective of circulatory demands.
- ‘Structural heart disease’ can cause syncope when circulatory demands outweigh the impaired ability of the heart to increase its output.
- ‘Steal’ syndromes can cause syncope when a blood vessel has to supply both part of the brain and an arm.
Causes of Non-syncopal Attacks (Commonly Misdiagnosed as Syncope)
A) Disorders with impairment or loss of consciousness: 1) Metabolic disorders*, including hypoglycaemia, hypoxia, hyperventilation with hypocapnia; 2) Epilepsy; 3) Intoxication; 4) Vertebro-basilar transient ischaemic attack (TIA).
B) Disorders resembling syncope without loss of consciousness: 1) Cataplexy; 2) Drop attacks; 3) Psychogenic ‘syncope’ (somatization disorders)**; 4) TIA of carotid origin
*Disturbance of consciousness probably secondary to metabolic effects on cerebrovascular tone.
**May also include hysteria, conversion reaction.
Pathophysiological classification of the principle known causes of transient loss of consciousness.
Adapted from EHJ. 2001;22(15):1260, Table 1.1