When viewing this topic in a different language, you may notice some differences in the way the content is structured, but it still reflects the latest evidence-based guidance.

Atrioventricular block

Last reviewed: 16 Jan 2026
Last updated: 10 Dec 2025

Summary

Definition

History and exam

Key diagnostic factors

  • age >50-60 years
  • underlying cardiovascular factors
  • syncope
  • heart rate <40 bpm
  • presyncope
Full details

Other diagnostic factors

  • male gender
  • fatigue
  • dyspnea
  • chest pain, palpitations, and nausea or vomiting
  • high (less commonly, low) blood pressure
  • cannon A waves
  • hypoxemia
  • family history of AV block
  • features of Lyme disease
Full details

Risk factors

  • age-related degenerative changes in the conduction system
  • increased vagal tone
  • AV-nodal blocking agents
  • chronic stable coronary artery disease
  • acute coronary syndrome
  • recent cardiac surgery, intervention, or ablation
  • congestive heart failure (CHF)
  • hypertension
  • cardiomyopathy
  • left ventricular hypertrophy
  • acid-base or electrolyte disturbance
  • neuromuscular disorders
  • sarcoidosis
  • giant cell myocarditis
  • cardiac tuberculosis
  • lyme disease
  • infective endocarditis
  • hypoxemia
  • blunt cardiac injury
  • some indigenous medicines
Full details

Diagnostic investigations

1st investigations to order

  • 12-lead ECG
  • serum troponin
  • serum potassium
  • serum calcium
  • serum pH
  • serum digitalis level
Full details

Investigations to consider

  • 24-hour ambulatory monitoring or event monitoring
  • chest x-ray
  • transthoracic echocardiogram
  • serologic testing for Lyme disease
  • tilt-table testing
  • electrophysiology study
  • cardiac stress testing
  • coronary angiography
  • serum CK-MB
Full details

Treatment algorithm

ACUTE

first-degree AV block or type I second-degree AV block

type II second-degree AV block or third-degree AV block

Contributors

Authors

Sanjiv Petkar, MD, FRCP

Consultant Cardiologist/Electrophysiologist

Royal Wolverhampton NHS Trust

Heart and Lung Centre

New Cross Hospital

Wolverhampton

UK

Disclosures

SP has received speaker's honoraria from Bayer, Bristol-Myers Squibb, MSD, and Pfizer. SP has received hospitality and/or accommodation from Bayer, Medtronic, St Jude, and Boston Scientific for attending conferences or meetings.

Dibbendhu Khanra, MD, DM Cardiology

International Clinical Fellow in Electrophysiology and Devices

Royal Wolverhampton NHS Trust

Heart and Lung Centre

New Cross Hospital

Wolverhampton

UK

Disclosures

DK declares that he has no competing interests.

Gaurav Panchal, MBBS, MRCP

Specialist Registrar in Cardiology/Electrophysiology

Royal Wolverhampton NHS Trust

Heart and Lung Centre

New Cross Hospital

Wolverhampton

UK

Disclosures

GP declares that he has no competing interests.

Acknowledgements

Dr Petkar, Dr Khanra, and Dr Panchal would like to gratefully acknowledge Dr Pathiraja, Dr Aziz, Dr Susan S. Kim, Dr John F. Beshai, and Dr Stephen L. Archer, previous contributors to this topic. JP, AA, SSK, JFB, and SLA declare that they have no competing interests.

Peer reviewers

Bradley P. Knight, MD

Professor of Medicine

Section of Cardiology

Director

Cardiac Electrophysiology

University of Chicago Medical Center

Chicago

IL

Divulgaciones

BPK declares that he has no competing interests.

Martin C. Burke, DO

Associate Professor of Medicine

Section of Cardiology

Cardiac Electrophysiology

University of Chicago Medical Center

Chicago

IL

Divulgaciones

MCB declares that he has no competing interests.

Nick Gall, MSc, MD, FRCP

Consultant Cardiologist

King’s College Hospital

London

UK

Divulgaciones

NG declares that he has no competing interests.

Thomas A. Dewland, MD

Associate Professor of Medicine

University of California

San Francisco

CA

Divulgaciones

TAD declares that he has no competing interests.

Agradecimiento de los revisores por pares

Los temas de BMJ Best Practice se actualizan de forma continua de acuerdo con los desarrollos en la evidencia y en las guías. Los revisores por pares listados aquí han revisado el contenido al menos una vez durante la historia del tema.

Divulgaciones

Las afiliaciones y divulgaciones de los revisores por pares se refieren al momento de la revisión.

Referencias

Nuestros equipos internos de evidencia y editoriales colaboran con colaboradores expertos internacionales y revisores pares para garantizar que brindemos acceso a la información más clínicamente relevante posible.

Artículos principales

Kusumoto FM, Schoenfeld MH, Barrett C, et al. 2018 ACC/AHA/HRS guideline on the evaluation and management of patients with bradycardia and cardiac conduction delay: a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. Circulation. 2019 Aug 20;140(8):e382-482.Texto completo  Resumen

Tracy CM, Epstein AE, Darbar D, et al. 2012 ACCF/AHA/HRS focused update of the 2008 guidelines for device-based therapy of cardiac rhythm abnormalities: a report of the American College of Cardiology Foundation/American Heart Association task force on practice guidelines. Heart Rhythm. 2012 Oct;9(10):1737-53.Texto completo  Resumen

Glikson M, Nielsen JC, Kronborg MB, et al; ESC National Cardiac Societies; ESC Scientific Document Group. 2021 ESC Guidelines on cardiac pacing and cardiac resynchronization therapy. Eur Heart J. 2021 Sep 14;42(35):3427-520.Texto completo  Resumen

Artículos de referencia

Una lista completa de las fuentes a las que se hace referencia en este tema está disponible para los usuarios con acceso a todo BMJ Best Practice.
  • Atrioventricular block images
  • Diferenciales

    • Junctional rhythm
    • Supraventricular tachycardia (SVT)
    • Atrial fibrillation or multifocal atrial tachycardia (MAT)
    Más Diferenciales
  • Guías de práctica clínica

    • 2025 appropriate use criteria for implantable cardioverter-defibrillators, and cardiac resynchronization therapy, and pacing
    • 2022 AHA/ACC/HFSA guideline for the management of heart failure
    Más Guías de práctica clínica
  • Folletos para el paciente

    Atrial fibrillation

    Heart attack

    Más Folletos para el paciente
  • padlock-lockedInicie sesión o suscríbase para acceder a todo el BMJ Best Practice

El uso de este contenido está sujeto a nuestra cláusula de exención de responsabilidad