Adams-Stokes syndrome

Synonyms and key words: Morgagni-Adams-Stokes syndrome or Stokes-Adams Attack

Overview
This refers to a sudden, transient episode of syncope, occasionally featuring seizures. It is named after two Irish physicians, Robert Adams (1791–1875) and William Stokes (1804–1877).

Pathophysiology
The attacks are caused by loss of cardiac output due to cardiac asystole, heart block, or ventricular fibrillation. The resulting lack of blood flow to the brain is responsible for the syncope.

Signs and symptoms
Prior to an attack, a patient may become pale, their heart rhythm experiences a temporary pause, and collapse may follow. Normal periods of unconsciousness last approximately thirty seconds; if seizures are present, they will consist of twitching after 15–20 seconds. Breathing continues normally throughout the attack, and so on recovery the patient becomes flushed as the heart rapidly pumps the oxygenated blood from the pulmonary beds into a systemic circulation which has become dilated due to hypoxia.

As with any syncopal episode that results from a cardiac dysrhythmia, the faints do not depend on the patient's position. If they occur during sleep, the presenting symptom may simply be feeling hot and flushed on waking.

Diagnosis
Stokes-Adams attacks may be diagnosed from the history, with paleness prior to the attack and flushing after it particularly characteristic. The ECG will show asystole or ventricular fibrillation during the attacks.

Treatment
Initial treatment can be medical, involving the use of drugs like isoproterenol (Isuprel)and epinephrine (Adrenalin). Definitive treatment is surgical, involving the insertion of a pacemaker – most likely one with sequential pacing such as a DDI mode as opposed to the older VVI mechanisms.

Prognosis
If undiagnosed (or untreated), Stokes-Adams attacks have a 50% mortality within a year of the first episode. The prognosis following treatment is very good.