Heart failure & cardiomyopathiesResearch article
Interatrial block in hypertrophic cardiomyopathy: Associations with left atrial remodeling and adverse atrial outcomes
- multicenter study
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
IAB vs No IAB
hazard ratio 2.11 (95% CI 1.13–3.95); P = 0.019
Further findings
LA diameter
Indexed maximum LA volume
| Outcome | hazard ratio (95% CI) | P value | |
|---|---|---|---|
| New-onset AF · median 5.8-year follow-up | 2.10 (1.07–4.16) | P = 0.031 | |
| 0.20.5125Hazard ratio (log scale) |
Median
| Outcome | IAB | No IAB | Estimate | P value |
|---|---|---|---|---|
| LA ejection fraction | 48% | 51% | ||
| LA reservoir strain | 22.0% | 29.3% | ||
| LA conduit strain | 8.3% | 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
Summarised from the published abstract; every number is checked against it