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The prevalence and prognosis of third-degree atrioventricular conduction block: the Reykjavik study

E M Kojic1, T Hardarson, N Sigfusson

  • 1Department of Medicine, National University Hospital, Reykjavik, Iceland.

Journal of Internal Medicine
|August 14, 1999
PubMed

Insights

The prevalence of third-degree atrioventricular block is low in the general population. Most cases are temporary and linked to underlying heart disease, with fewer individuals requiring pacemakers than anticipated.

Area of Science:

  • Cardiology
  • Epidemiology

Background:

  • Previous studies on third-degree atrioventricular block (AVB) primarily focused on hospital patients and specific professional groups.
  • Limited data exists on the prevalence and prognostic significance of third-degree AVB in the general population.

Purpose of the Study:

  • To determine the prevalence of third-degree atrioventricular block in a representative population sample.
  • To assess the prognostic implications of third-degree AVB.

Main Methods:

  • Prospective cardiovascular population study (Reykjavik Study) involving 9139 men and 9773 women aged 33-79 years (1967-91).
  • Electrocardiograms were recorded and coded using the Minnesota code.
  • Prevalence and outcomes of third-degree AVB were analyzed.

Main Results:

  • Third-degree atrioventricular block was identified in 11 individuals (0.04% prevalence).
  • The condition was temporary in 64% of cases.
  • All affected individuals had coexisting heart disease; 55% required a pacemaker.

Conclusions:

  • The prevalence of third-degree AVB in the general population is low.
  • Third-degree AVB is often temporary and associated with underlying heart disease, which may be a more significant prognostic factor.
  • Fewer individuals than expected required pacemaker implantation.
Abstract

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