Heart failure & cardiomyopathies

Interatrial block in hypertrophic cardiomyopathy: Associations with left atrial remodeling and adverse atrial outcomes

Heart RhythmPublished multicenter study

Main finding · Composite of new-onset AF, transient ischemic attack, or ischemic strokeResult — go to the resultHazard ratio 2.11 95% CI 1.13–3.95

Authors' conclusion

In patients with HCM, IAB is associated with significant LA structural and functional impairments, indicative of advanced atrial cardiomyopathy. Its presence was independently associated with an increased risk of incident AF and stroke, suggesting its value as a simple, accessible electrocardiographic marker for enhanced risk stratification.

Study context

Population
Patients with hypertrophic cardiomyopathy (HCM) without a history of AF/stroke
Participants
259 patients
Comparison
Interatrial block (IAB) vs no IAB
Outcome
Composite of:
  • New-onset AF
  • Transient ischemic attack
  • Ischemic stroke
Follow-up
median 5.8-year follow-up

Main finding

As reported in the abstract

Hazard ratio

2.11

95% CI 1.13–3.95

P = 0.019

IABvs No IAB
hazard ratio 2.11 (95% CI 1.13–3.95); P = 0.019

Further findings

LA diameter

Indexed maximum LA volume

OutcomeHazard ratio (95% CI)P value
New-onset AF · median 5.8-year follow-up2.10 (1.07–4.16)P = 0.031

Median

OutcomeIABNo IAB
LA ejection fraction48%51%
LA reservoir strain22.0%29.3%
LA conduit strain8.3%12.1%
  • Left atrial (LA) diameter: P = .022
  • Indexed maximum LA volume: P = .043
  • LA ejection fraction: P = .043
  • LA reservoir strain: P = .018
  • LA conduit strain: P = .012

Prevalence of IAB

IAB present in cohort
10%

Original publication

Interatrial block in hypertrophic cardiomyopathy: Associations with left atrial remodeling and adverse atrial outcomes. Heart Rhythm. Published 3 February 2026. doi:10.1016/j.hrthm.2026.01.040

Composed by AI from the published abstract and checked against it. How Briefs are made →

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