Heart failure & cardiomyopathiesCohort study
Electrophysiological Characterization of Subclinical and Overt Hypertrophic Cardiomyopathy by Magnetic Resonance Imaging-Guided Electrocardiography
- Prospective cohort study
- multicentre
Authors' conclusion
In the absence of LVH or 12-lead ECG abnormalities, HCM sarcomere gene mutation carriers express an aberrant EP phenotype detected by ECGI. In overt HCM, abnormalities occur more severely with adverse structural change and positive genetic status.
Study context
- Population
- Sarcomere gene mutation carriers without LVH, patients with overt hypertrophic cardiomyopathy (HCM), and healthy volunteers
- Participants
- 211 carriers
- Exposure
- Subclinical HCM and overt HCM vs healthy volunteers, by cardiovascular magnetic resonance (CMR)-guided electrocardiographic imaging (ECGI)
Main finding
As reported in the abstract
EP abnormalities by ECGI
- Mean activation time (AT) prolonged in subclinical HCM vs HV
- P = 0.008
- Mean AT prolonged in subclinical HCM vs HV with normal 12-lead electrocardiograms (ECGs)
- P = 0.009
- Repolarization more spatially heterogeneous in subclinical HCM vs HV (GRTc)
- P = 0.005
- Corrected activation-recovery interval prolonged in overt vs subclinical HCM
- P < 0.001
- More fractionation in G+LVH+ vs G-LVH+
- P = 0.002
Observational data: associations, not effects.
Further findings
Association of electrophysiological (EP) markers with structure
- Mean AT associated with maximal wall thickness; GAT and fractionation associated with scar
- all P < 0.05
Support vector machine discrimination
- Subclinical HCM vs HV, 10-fold cross-validation accuracy
- 80% [95% CI: 73%-85%]
- Identification of patients at higher risk of SCD, accuracy
- 82% [95% CI: 78%-86%]
Parts of this Brief are withheld: the automatic checks could not confirm them against the abstract.
Original publication
Electrophysiological Characterization of Subclinical and Overt Hypertrophic Cardiomyopathy by Magnetic Resonance Imaging-Guided Electrocardiography. J Am Coll Cardiol. Published 20 February 2024. doi:10.1016/j.jacc.2024.01.006
Summarised from the published abstract; every number is checked against it