Download - Mechanisms of Tachycardias
Mechanisms of Tachycardias
• Abnormalities in impulse generation (automatic tachycardias)
• Abnormalites in impulse conduction
(reentrant tachycardias)
Clinical examples
• Atrial fibrillation
• Reentrant PSVT
• Ventricular tachycardia/fibrillation
Atrial Fibrillation - causes
• Atrial stretch
• High sympathetic tone
• Idiopathic or “lone”
Atrial fibrillation - complications
• Worsened heart failure
• Recurrences
• Thromboembolism (CVA 3-5%/yr)
Reentrant PSVT
• AV Nodal Reentry
• AV Reentry (WPW)
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