Management of Persistent Bradycardia

First-Line Treatment Approach

The American College of Cardiology recommends atropine as the first-line pharmacological treatment for symptomatic bradycardia at doses of 0.5-1 mg IV, which may be repeated every 3-5 minutes to a maximum dose of 3 mg 1, 3
If bradycardia is unresponsive to atropine, second-line therapy with chronotropic agents should be initiated, as recommended by the American Heart Association 3, 2

Dopamine provides dose-dependent effects that can be tailored to the clinical situation, with enhanced chronotropy and inotropy at 5-20 mcg/kg/min, as stated by the American College of Cardiology 1, 4, 5
The American College of Cardiology recommends starting dopamine at 5 mcg/kg/min and increasing by 5 mcg/kg/min every 2 minutes based on response, with a maximum dose of 20 mcg/kg/min 6, 2
Noradrenaline (epinephrine) is recommended at a dose of 2-10 mcg/min IV or 0.1-0.5 mcg/kg/min IV, titrated to desired effect, according to the American Heart Association 1, 4
Noradrenaline has strong alpha-adrenergic and beta-adrenergic stimulatory effects, but may cause excessive vasoconstriction and increased myocardial oxygen consumption, as noted by the American College of Cardiology 4

The American Heart Association recommends assessing for reversible causes of bradycardia and treating if identified, with a treatment approach that includes administering atropine 0.5-1 mg IV if patient has symptomatic bradycardia or hemodynamic compromise 1, 5, 3
If bradycardia persists despite atropine, the American College of Cardiology recommends initiating dopamine at 5 mcg/kg/min IV, increasing by 5 mcg/kg/min every 2 minutes to a maximum of 20 mcg/kg/min, with monitoring for excessive tachycardia or arrhythmias at higher doses 1, 6
If dopamine is ineffective or contraindicated, the American Heart Association suggests considering epinephrine (noradrenaline) at 2-10 mcg/min IV or 0.1-0.5 mcg/kg/min, with alternative agents including isoproterenol (1-20 mcg/min) or dobutamine 1, 4, 2

The American College of Cardiology advises caution with dopamine dosing, as doses >20 mcg/kg/min may result in excessive vasoconstriction and arrhythmias, and recommends continuous cardiac monitoring and ideally arterial blood pressure monitoring for all patients requiring vasopressors 1, 6, 9
The American Heart Association recommends considering transcutaneous pacing if pharmacologic therapy fails, and notes that specific clinical scenarios may warrant alternative approaches, such as aminophylline or theophylline for bradycardia after heart transplant or spinal cord injury, or calcium, glucagon, or high-dose insulin therapy for bradycardia due to beta-blocker or calcium channel blocker overdose 8, 7, 6, 4