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Cardiology6 papers

First degree atrioventricular block

Last edited: 4/22/2026

Overview

First-degree atrioventricular (AV) block is characterized by a prolonged PR interval on the surface electrocardiogram (ECG) without complete AV block. It is relatively common in asymptomatic young individuals with reported prevalences ranging from 0.65% to 1.1% 2.

Diagnosis

  • Key Diagnostic Criteria: Prolonged PR interval on ECG 2.
  • Recommended Tests: Exclusion of organic heart disease through clinical evaluation and possibly additional ECG monitoring 2.
  • Grading: Not typically graded; diagnosis based on ECG findings 2.
  • Management

  • First-Line Management: No specific treatment required; management focuses on monitoring and exclusion of underlying causes 2.
  • Adjunctive Treatments: Not typically indicated unless associated with other conditions requiring intervention 2.
  • Special Populations

  • Pregnancy: No specific guidance provided in the abstracts 1.
  • Pediatrics: No specific guidance provided in the abstracts 1.
  • Elderly: No specific guidance provided in the abstracts 1.
  • Comorbidities: Focus on excluding organic heart disease in all populations 2.
  • Key Recommendations

  • First-degree AV block is generally benign and does not warrant restriction on fitness to fly 2 (Evidence: Strong).
  • Detailed invasive investigations are not typically necessary unless organic heart disease is suspected 2 (Evidence: Strong).
  • Increased electrocardiographic scrutiny may be considered for individuals diagnosed with first-degree AV block 2 (Evidence: Moderate).
  • References

    1 Michau A, Gitz L, Proulx F, Besse M, Tezenas du Montcel S, Leclère B et al.. Pulsed Doppler fetal atrioventricular interval measurement: Assessment of a new image scoring method. Journal of gynecology obstetrics and human reproduction 2019. link 2 Bexton RS, Camm AJ. First degree atrioventricular block. European heart journal 1984. link

    Original source

    1. [1]
      Pulsed Doppler fetal atrioventricular interval measurement: Assessment of a new image scoring method.Michau A, Gitz L, Proulx F, Besse M, Tezenas du Montcel S, Leclère B et al. Journal of gynecology obstetrics and human reproduction (2019)
    2. [2]
      First degree atrioventricular block.Bexton RS, Camm AJ European heart journal (1984)

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