isoproterenol challenge
Pronunciation: eye-so-pro-TER-eh-nol
Pharmacologic provocation test using beta-adrenergic stimulation to unmask latent arrhythmias during EP studies.
Full Definition
A pharmacologic provocation technique used during electrophysiology studies to unmask latent arrhythmias or conduction abnormalities that may not be apparent at baseline. Isoproterenol, a beta-adrenergic agonist, increases heart rate and contractility while shortening refractory periods, potentially triggering arrhythmias in susceptible patients. This test is particularly valuable for evaluating patients with syncope of unknown etiology, suspected catecholaminergic polymorphic ventricular tachycardia, or Brugada syndrome. Proper documentation requires detailed dosing protocols, hemodynamic responses, and any induced arrhythmic events.
Usage
Usage note: Always document specific dosing and titration protocol used.
In Context
- "Isoproterenol challenge at 2 mcg/min induced reproducible polymorphic ventricular tachycardia." — EP study report
- "No arrhythmias were provoked despite maximum isoproterenol infusion up to 4 mcg/min." — Negative EP study note