What is the treatment for bradycardia (abnormally slow heart rate)?

From the Guidelines

The treatment for bradycardia should prioritize atropine as the first-line medication, administered at 0.5 mg IV every 3-5 minutes up to a maximum of 3 mg, as recommended by the most recent guidelines 1. The approach to treating bradycardia depends on the severity of symptoms and the underlying cause. For symptomatic bradycardia, characterized by a heart rate below 60 beats per minute with symptoms such as dizziness, fatigue, or syncope, immediate intervention is necessary.

• Atropine is the first-line medication for acute symptomatic bradycardia, with a recommended dose of 0.5 mg IV every 3 to 5 minutes to a maximum total dose of 3 mg, as supported by clinical trials and guidelines 1.
• If atropine is ineffective, temporary transcutaneous pacing may be required, followed by transvenous pacing if needed, to acutely treat bradycardia causing hemodynamically significant instability 1.
• For long-term management, permanent pacemaker implantation is often recommended for symptomatic bradycardia that doesn't respond to medication or has an irreversible cause.
• Asymptomatic bradycardia usually requires no treatment, but underlying causes such as medication side effects, hypothyroidism, or electrolyte imbalances should be addressed.
• In athletes, bradycardia is often a normal physiological adaptation to training and typically requires no intervention. Key considerations in the treatment approach include:
• Maintaining adequate cardiac output by ensuring an appropriate heart rate
• Addressing the root cause of the slow heart rhythm
• Monitoring for worsening symptoms that may indicate progression requiring medical attention, as advised in the guidelines 1.

From the FDA Drug Label

Atropine Sulfate Injection, USP in clinical doses counteracts the peripheral dilatation and abrupt decrease in blood pressure produced by choline esters ... Adequate doses of atropine abolish various types of reflex vagal cardiac slowing or asystole The drug also prevents or abolishes bradycardia or asystole produced by injection of choline esters, anticholinesterase agents or other parasympathomimetic drugs, and cardiac arrest produced by stimulation of the vagus.

The treatment for bradycardia (abnormally slow heart rate) is atropine.

• Atropine counteracts reflex vagal cardiac slowing or asystole and prevents or abolishes bradycardia or asystole. 2

From the Research

Treatment Options for Bradycardia

• The treatment for bradycardia (abnormally slow heart rate) depends on the underlying cause and severity of symptoms.
• For symptomatic bradycardia, treatment options include:
  • Atropine administration as a first-line therapy 3, 4, 5
  • Pacemaker implantation, which may be necessary for patients with disorders of impulse formation and conduction 6
  • Percutaneous pacing as a bridge to definitive treatment 4
• In some cases, glucagon may be used to treat drug-induced symptomatic bradycardia, particularly in the presence of beta-adrenergic blockade and calcium channel blockade 7
• For asymptomatic patients, treatment may not be necessary, but monitoring and follow-up are recommended to assess for any changes in symptoms or condition 6, 4

Considerations for Treatment

• Prior to definitive pacemaker implantation, reversible or preventable causes of bradycardia must be investigated and treated 6
• The location of the heart block may affect the response to atropine administration, with patients with atrioventricular blocks at the level of the His-Purkinje fibers being at increased risk of adverse events 3
• Paramedics and healthcare providers should be prepared to manage unexpected adverse events secondary to atropine administration in patients with heart block 3