Electrophysiologic mechanisms of the long QT interval syndromes and torsade de pointes
Article Abstract:
Long QT interval syndromes are caused by delayed repolarization in the cardiac cells which may trigger a rapid, irregular heart rhythm called torsade de pointes. The QT interval is recorded on an electrocardiogram which captures the electrical activity of the heart. Long QT interval syndromes may be acquired or hereditary. The acquired form is caused by drugs or conditions that disrupt the normal flow of ions into or out of cardiac cells. An ion imbalance prohibits the heart from repolarizing normally which prolongs the QT interval and triggers torsade de pointes. The hereditary form of the long QT interval syndrome may have a genetic basis and may be caused by an abnormal response to adrenergic or sympathetic nervous system stimulation. Physicians must identify and eliminate agents or condition that precipitate the long QT interval syndromes and torsade de pointes. Therapy may include drugs that modulate the movement of ions through cell membranes or implantable devices that restore normal heart rhythm.
Publication Name: Annals of Internal Medicine
Subject: Health
ISSN: 0003-4819
Year: 1995
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The role of intravenous amiodarone in the management of cardiac arrhythmias
Article Abstract:
Amiodarone therapy appears to be effective in correcting abnormal heart rhythms, particularly when given directly into the bloodstream. Research studies on amiodarone therapy published or presented between 1985 and 1996 are summarized and analyzed. Patients with abnormal rhythms associated with a heart attack or those originating at or around the lower heart chambers appear to benefit from short-term amiodarone therapy. Fewer side effects have been reported with amiodarone therapy given directly into the bloodstream compared to therapy given by mouth.
Publication Name: Annals of Internal Medicine
Subject: Health
ISSN: 0003-4819
Year: 1997
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