Asystole - Symptom, Causes, Treatment

Asystole is defined as the complete absence of electrical activity in the myocardium. Asystole is usually caused by ventricular fibrillation. It is one of the conditions required for a medical practitioner to certify death. Asystole can be primary or secondary. Primary asystole occurs when the heart's electrical system intrinsically fails to generate a ventricular depolarization. This may result from ischemia or from degeneration of the sinoatrial node or atrioventricular conducting system. Secondary asystole occurs when factors outside of the heart's electrical conduction system result in a failure to generate any electrical depolarization. Asystole is cardiac standstill with no cardiac output and no ventricular depolarization; it eventually occurs in all dying patients. Asystole or bradyasystole follows untreated VF and commonly occurs after unsuccessful attempts at defibrillation.

Asystole is associated with a poor outcome regardless of its initial cause. In asystole, the heart will not respond to defibrillation because it is already depolarized, however some emergency physicians advocate a trial of defibrillation in case the rhythm is actually fine ventricular fibrillation, although little evidence exists to support the practice. Frequency of asystole, as a percentage of all cardiopulmonary arrests, is higher in women than in men; however, the frequency of cardiac arrest in general is proportional to the underlying incidence of heart disease, which is more common in males until around 75 years of age. There are no specific treatment for asystole. Primary asystole may be prevented by the appropriate use of a permanent pacemaker in those patients who have high-grade heart block or sinus arrest.

Causes of Asystole

Some common causes of asystole are as follows:

• Ventricular fibrillation.
• Stroke, massive pulmonary embolus.
• Defibrillation, and sedative-hypnotic or narcotic overdoses leading to respiratory failure.
• Suffocation, near drowning.
• Congenital heart block, local tumor, or cardiac trauma.

Treatment of Asystole

Some most common treatmet of asystole:

• Asystole may be prevented by the appropriate use of a permanent pacemaker in those patients who have high-grade heart block or sinus arrest.

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