A familial disorder characterized by
spontaneous idiopathic ventricular fibrillation that probably is one of the
most frequent causes of sudden death in patients with a structurally normal heart.
Idiopathic Ventricular Fibrillation; Right Bundle Branch
Block, ST-Segment Elevation, and Sudden Death Syndrome.
Prevalence is estimated to be 1:10,000 to 5:10,000 in
the general population in western countries. Higher frequency (1:2500) may
be found in eastern countries.
Autosomal dominant. Approximately 3/4 of clinically
affected individuals are males.
Caused by mutations in the gene encoding the
α-subunit of the voltage-gated sodium channel type V (SCN5A). A reentrant mechanism has
been evocated. Loss of the dome of the action potential occurs because of an
ion imbalance during phase 1 of the action
potential. Increasing the potassium current increases ST-segment elevation,
whereas interventions increasing calcium current diminish ST-segment
elevation and vice versa.
Based on the typical electrocardiographic pattern of
ST-segment elevation in leads V1 to V3 and incomplete or complete
right bundle branch block. Genetic studies can confirm the diagnosis, but a
negative result does not exclude the diagnosis.
Syncope and cardiac arrest, typically occurring
in the third and fourth decade of life, usually at rest or during sleep.
However, all ages can be symptomatic. Classification of patients is not clearly
established, but history of syncope and spontaneous electrocardiographic
modifications seems to bear a bad prognosis. Intracardiac defibrillators have
been used successfully.
Obtain full familial and personal
history. Evaluate cardiac status (clinical, electrocardiogram). Evaluate perioperative
electrolyte levels (Na, Ca, K).
Successful anesthetic management of
patients with Brugada syndrome has been described for general and regional anesthesia.
Resuscitation devices must be present at all times
(internal or external defibrillator). Perioperative cardiac monitoring is
imperative. In high-risk patients (syncope and spontaneous electrocardiographic
modifications), benefit of preoperative intracardiac defibrillator
implantation must be considered.
Perioperative fluid regimen must
carefully consider the absolute necessity of electrolyte equilibrium.
Calcium blockers should be avoided. Amiodarone has been used successfully in
Arrhythmogenic Right Ventricular Dysplasia: Most often inherited
disease of the myocardium resulting in cardiomyopathy and risk of sudden
death in otherwise healthy young adults.
Edge CJ, Blackman DJ, Gupta K, et al: General anaesthesia in a patient with
Brugada syndrome. Br J Anaesth
Grant AO: Electrophysiological basis and genetics of Brugada syndrome. J
Cardiovasc Electrophysiol 16(Suppl 1):521, 2005.
Priori SG, Napolitano C, Gasparini M, et al: Natural history of Brugada
syndrome: Insights for risk stratification and management. Circulation