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Interatrial Block Association With Adverse Cardiovascular Outcomes in Patients Without a History of

Joshua Lampert1, David Power2, Shreyas Havaldar3

  • 1Helmsley Electrophysiology Center, Mount Sinai Hospital, New York, New York, USA. Electronic address: https://twitter.com/joshuamlampertmd.

JACC. Clinical Electrophysiology
|June 24, 2023
PubMed

Insights

Interatrial block (IAB) independently increases stroke risk in patients without a history of atrial fibrillation or atrial flutter (AF/AFL). This association persists even when accounting for incident AF/AFL, highlighting a significant risk even without identified arrhythmias.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Public Health

Background:

  • Interatrial block (IAB) is linked to thromboembolism and atrial arrhythmias.
  • Previous studies on IAB's predictive value for adverse outcomes, especially in atrial fibrillation/atrial flutter (AF/AFL) patients, were limited by small cohorts.

Purpose of the Study:

  • To investigate the association between Interatrial block (IAB) and stroke risk in a large patient cohort.
  • To determine if IAB predicts adverse outcomes in the presence or absence of atrial fibrillation/atrial flutter (AF/AFL).

Main Methods:

  • Retrospective analysis of 4,837,989 electrocardiograms (ECGs) from 1,228,291 patients across 5 centers.
  • IAB defined as P-wave duration ≥120 ms. Analysis excluded patients with prior AF/AFL.
  • Outcomes analyzed using restricted mean survival time and restricted mean time lost.

Main Results:

  • IAB was present in 19.6% of the analyzed cohort (86,317 patients).
  • IAB was independently associated with increased stroke probability (RMTLRC: 1.43), mortality (RMTLRC: 1.14), heart failure (RMTLRC: 1.94), and systemic thromboembolism (RMTLRC: 1.62).
  • IAB was not associated with stroke in patients with pre-existing AF/AFL.

Conclusions:

  • Interatrial block is an independent predictor of stroke in patients without a history of AF/AFL.
  • The association between IAB and stroke risk remains significant even after adjusting for incident AF/AFL and CHA2DS2-VASc score.
  • Patients with IAB face elevated stroke risk even when AF/AFL is not detected.
Abstract

Keywords:
atrial fibrillationelectrocardiogramfibrosisheart failureinteratrial blockstroke

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