Conditions
Complete (third-degree) heart block
Quick answer
Complete heart block means no electrical signals pass from the upper to the lower chambers. The ventricles beat on a slow backup rhythm. It causes fainting, breathlessness and fatigue. Almost all patients need a permanent pacemaker.
Medically reviewed by The Curaventa Team · Last updated 2026-10-24
What this stage or type means
- No conduction between atria and ventricles.
- Ventricular rate is often very slow.
- Can be congenital or acquired with age, heart attack or surgery.
- May present as sudden collapse.
- Needs urgent assessment.
Treatment options
Permanent pacemaker
Dual-chamber pacing is commonly used; leadless or conduction-system pacing are options in some.
Temporary pacing
Used in hospital until a permanent device is fitted.
Treat reversible causes
Such as drug toxicity or high potassium.
Tests that confirm it
- ECG
- Telemetry monitoring
- Echocardiogram
- Blood tests for electrolytes and Lyme disease where relevant
Outlook
With a pacemaker, outlook is generally good. The Cleveland Clinic states people with third-degree block almost always need one.
Planning treatment in India
- This can be an emergency; get stabilised locally before any travel.
- If travelling for a planned pacemaker, the stay is usually short.
- Send ECGs and any hospital notes.
- Make sure pacemaker follow-up is available near your home.
Questions to ask your specialist
- Is this block reversible?
- What kind of pacemaker suits me?
- Is conduction system pacing an option?
- How often will the device need checks?
Related treatments
Other stages and types
Frequently asked questions
Is complete heart block life-threatening?
It can be, because the heart rate may be too slow. A pacemaker treats it.
How long does a pacemaker battery last?
Usually many years; replacement is a smaller procedure.
Can children have complete heart block?
Yes, some are born with it. Paediatric cardiologists manage it.
Sources
Medically reviewed by The Curaventa Team. Last updated 2026-10-24. General information, not medical advice. Medical editorial board · Editorial policy · How we get prices
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