Snapshot A 68-year-old female on digoxin complains of lethargy. Her EKG is shown. Introduction Any tachycardic arrhythmia originating at or above the atrioventricular node SVTs from SA node Inappropriate sinus tachycardia Sinoatrial node reentrant tachycardia (SANRT) SVTs from atrial source Ectopic (unifocal) atrial tachycardia Multifocal atrial tachycardia Atrial fibrillation with a rapid ventricular response Atrial flutter with a rapid ventricular response SVTs from AV node AV nodal reentrant tachycardia (AVNRT) Junctional reciprocating tachycardia (JRT) AV reentrant tachycardia (AVRT) Wolff-Parkinson-White syndrome Junctional ectopic tachycardia Paroxysymal SVT specifically, an AV nodal re-entrant tachycardia NOT using accessory pathways Presentation Symptoms duration symptoms may present suddenly and resolve without intervention can last for minutes up to 1-2 days without resolution include heavy chest difficulty breathing pounding heart dizziness LOC numbness in certain body parts Physical exam rapid pulse (150-250+) Evaluation EKG narrow QRS complex wide-complex tachycardia that must be differentiated from VT Differential Multiple types of ventricular tachycardia, multifocal atrial tachycardia Treatment Valsalva maneuver, facial immersion, or carotid massage (best initial step) slow conduction through the AV node Medications to slow conduction through the AV node includes digoxin beta blockers adenosine CCBs note that these are contraindicated in Wolf-Parkinson-White syndrome Electrical cardioversion performed if it is a non-emergency situation and symptoms cannot be controlled medically Prognosis, Prevention, and Complications Prognosis not as dangerous as ventricular tachycardias Prevention once acute episode is terminated, may require continued treatment for prevention may require radiofrequency ablation