• ABSTRACT
    • Supraventricular tachycardia refers to rapid rhythms that originate and are sustained in atrial or atrioventricular node tissue above the bundle of His. The condition is caused by reentry phenomena or automaticity at or above the atrioventricular node, and includes atrioventricular nodal reentrant tachycardia, atrioventricular reciprocating tachycardia, and atrial tachycardia. Most persons with these tachyarrhythmias have structurally normal hearts. Sudden onset of an accelerated heart rate can cause palpitations, light-headedness, chest discomfort, anxiety, dyspnea, or fatigue. The history is important to elicit episodic symptoms because physical examination and electrocardiography findings may be normal. A Holter monitor or event recorder may be needed to confirm the diagnosis. Vagal maneuvers may terminate the arrhythmia; if this fails, adenosine is effective in the acute setting. Calcium channel blockers (diltiazem or verapamil) or beta blockers (metoprolol) can be used acutely or as long-term therapy. Class Ic antiarrhythmics (flecainide or propafenone) can be used long-term. Class Ia antiarrhythmics (quinidine, procainamide, or disopyramide) are used less often because of their modest effectiveness and adverse effects. Class III antiarrhythmics (amiodarone, sotalol, or dofetilide) are effective, but have potential adverse effects and should be administered in consultation with a cardiologist. Catheter ablation has a success rate of 95% and recurrence rate of less than 5%, and causes inadvertent heart block in less than 1% of patients. It is the preferred treatment for symptomatic patients with Wolff-Parkinson-White syndrome.