Highlights & Basics
- Sinus bradycardia is any heart rhythm slower than 50 bpm, even if transient, owing to sinus node dysfunction and/or atrioventricular (AV) conduction abnormalities.
- Causes include intrinsic sinus node, AV nodal, and His-Purkinje disease, or extrinsic influences, which may be reversible.
- Common symptoms include syncope, fatigue, and dizziness; however, the patient may be asymptomatic.
- Evaluation involves determining the association of symptoms with heart rate and an assessment of underlying cardiovascular conditions. A 12-lead ECG and/or a heart monitor are the diagnostic tests of choice.
- Patients with a reversible cause may not require long-term therapy; however, patients with nonreversible causes may require an implantable pacemaker with or without a defibrillator. Urgent treatment may include temporary pacing and drug interventions.
Quick Reference
History & Exam
Key Factors
Other Factors
Diagnostics Tests
Treatment Options
Definition
Epidemiology
Etiology
Pathophysiology
Images
ECG showing sinus pause
ECG showing tachy-brady syndrome
ECG showing tachy-brady syndrome
ECG showing tachy-brady syndrome
ECG showing tachy-brady syndrome
ECG showing first-degree atrioventricular (AV) block
ECG showing Mobitz I (Wenckebach) second-degree atrioventricular (AV) block
ECG showing Mobitz I (Wenckebach) second-degree atrioventricular (AV) block
ECG showing Mobitz I (Wenckebach) second-degree atrioventricular (AV) block during acute inferior wall myocardial infarction
ECG showing Mobitz II second-degree atrioventricular (AV) block
ECG showing Mobitz II second-degree atrioventricular (AV) block
ECG showing 2:1 atrioventricular (AV) block
ECG showing 2:1 atrioventricular (AV) block
ECG showing complete atrioventricular (AV) block
ECG showing complete atrioventricular (AV) block
ECG showing complete atrioventricular (AV) block with ventricular escape
ECG showing complete atrioventricular (AV) block with ventricular escape
ECG showing complete atrioventricular (AV) block with junctional escape
ECG showing junctional rhythm
ECG showing interference atrioventricular (AV) dissociation
ECG showing interference atrioventricular (AV) dissociation
Citations
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