title: Adenosine-induced tachycardia acceleration: an unusual proarrhythmia.
abstract: Adenosine is an effective agent for termination of most re-entrant supraventricular arrhythmias involving the atrioventricular node and often also used as a diagnostic agent for wide QRS tachycardias. Adenosine terminates 90-99% of re-entrant supraventricular tachycardias but it may rarely accelerate tachycardias. Adenosine-induced tachycardia acceleration is a rare phenomenon, as only a handful of cases have been described in the literature. We present a case of a 36-year-old man with a narrow complex, short RP tachycardia at a rate of 165 bpm and an initial blood pressure of 110/78 mm Hg. A bolus of 12 mg of adenosine resulted in slowing of the tachycardia to 150 bpm for 2-3 s, followed by acceleration of the tachycardia to 185 bpm that lasted for approximately 20 s and returned to baseline at 165 bpm. The main mechanism of adenosine-induced acceleration may be the secondary sympathetic stimulation, which may be preceded by transient bradycardia and/or hypotension.
authors: Michigan State University, Lansing, Michigan, USA.
authors: Vini
authors: V
authors: Singh
authors: Department of Cardiology, Michigan State University, Lansing, Michigan, USA.
authors: Negar
authors: N
authors: Salehi
authors: Department of Cardiology, Sparrow Thoracic and Cardiovascular Institute, Lansing, Michigan, USA.
authors: Ranjan Kumar
authors: RK
authors: Thakur
mesh_terms: D000241:Adenosine / Q000009:adverse effects*; D000328:Adult; D000889:Anti-Arrhythmia Agents / Q000009:adverse effects*; D004562:Electrocardiography; D006339:Heart Rate; D006801:Humans; D008297:Male; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000139:chemically induced*; D013617:Tachycardia, Supraventricular / Q000188:drug therapy
chemical_list: D000889:Anti-Arrhythmia Agents; D000241:Adenosine
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