Management of Right Bundle Branch Block

Diagnosis and Evaluation

The American College of Cardiology defines complete RBBB as QRS duration ≥120 ms with specific morphology criteria, and incomplete RBBB as QRS duration between 110-119 ms with similar morphology 1
A 12-lead ECG should be performed to confirm RBBB and identify any associated abnormalities, such as first-degree AV block, left anterior or posterior fascicular block, or ST-segment or T-wave changes 1
Additional testing, including echocardiography, exercise stress testing, or ambulatory ECG monitoring, may be considered based on clinical presentation 1

For patients with STEMI who develop RBBB with first-degree AV block, the American College of Cardiology recommends applying transcutaneous pacing pads (Class I recommendation) 2
Temporary transvenous pacing may be considered for patients with STEMI who develop RBBB with first-degree AV block (Class IIb recommendation) 2
Observation alone or atropine administration is not indicated for patients with STEMI who develop RBBB with first-degree AV block (Class III) 2

In patients with chest pain and RBBB, the European Heart Journal notes that RBBB alone does not significantly increase the likelihood of myocardial infarction compared to patients without RBBB 3
The European Heart Journal recommends considering further cardiac evaluation if RBBB is accompanied by symptoms or other abnormal findings, such as ST-segment depression in leads I, aVL, and V5-6, which may indicate NSTE-ACS 3
The European Heart Journal suggests awaiting high-sensitivity troponin results before deciding on immediate coronary angiography in patients with chest pain and RBBB 3