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Atrial induction of ventricular tachycardia: reentry versus triggered automaticity
The American Journal of Cardiology
|July 1, 1979
Summary
Atrial stimulation triggered sustained ventricular tachycardia in patients with mitral valve prolapse and hypertension. Mechanisms included reentrant excitation and triggered automaticity, likely originating from a small area in the left ventricle.
Area of Science:
- Cardiology
- Electrophysiology
Background:
- Mitral valve prolapse and hypertension are common conditions.
- Ventricular tachycardia (VT) is a potentially life-threatening arrhythmia.
Purpose of the Study:
- To investigate the induction and mechanisms of sustained ventricular tachycardia.
- To identify potential triggers and origins of VT in specific patient groups.
Main Methods:
- Atrial stimulation was used to induce ventricular tachycardia.
- Clinical presentation and electrophysiological findings were analyzed.
- Mechanisms of VT, including reentrant excitation and triggered automaticity, were explored.
Main Results:
- Sustained ventricular tachycardia was induced in patients with mitral valve prolapse and mild hypertension.
- Exercise-induced sinus tachycardia also triggered VT in one patient.
- Evidence suggests localized reentrant excitation and triggered automaticity as mechanisms, originating from the posteroinferior left ventricle.
Conclusions:
- Atrial stimulation can induce sustained VT in susceptible individuals.
- VT mechanisms in these cases appear to be localized and not macroreentrant.
- Understanding these mechanisms is crucial for managing VT in patients with underlying cardiac conditions.
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