Heart Rhythm (Arrhythmias) & Devices
Left Bundle Branch Block (LBBB)
The left bundle carries each beat to the left side of the heart. When it is blocked, the signal takes a longer route and the QRS looks wider.
This is a free, plain-language patient education guide written by Rias Ali, MD, FACC, a board-certified interventional cardiologist. Every guide is grounded in current peer-reviewed evidence and major society guidelines, organized in a way patients can actually use during a visit.
Download the Left Bundle Branch Block (LBBB) guide
What's inside this guide
- Plain-language explanation of left bundle branch block (lbbb)
- Why it matters and what the major risks are
- Treatment options with risks, benefits, and alternatives
- Common misconceptions clarified
- Lifestyle and self-care advice
- Specific warning signs — when to call us, when to call 911
- Sources used to build the guide (peer-reviewed and society guidelines)