Differences in Repolarization Heterogeneity Among Heart Failure With Preserved Ejection Fraction Phenotypic...

Area of Science:

• Cardiology
• Biomedical Engineering
• Computational Biology

Background:

• Heart failure with preserved ejection fraction (HFpEF) is a complex syndrome with diverse patient phenotypes.
• Previous research identified three distinct HFpEF phenogroups using machine learning, each with unique clinical characteristics and outcomes.
• The underlying pathophysiological differences between these phenogroups require further elucidation.

Purpose of the Study:

• To investigate whether repolarization heterogeneity differs among the three previously defined HFpEF phenogroups.
• To assess the association between repolarization heterogeneity, specifically the T-peak to T-end (TpTe) interval, and HFpEF phenogroups.

Main Methods:

• A systematic observational study involving 201 HFpEF patients.
• Electrocardiograms (ECGs) were analyzed to measure the T-peak to T-end (TpTe) interval, an index of repolarization heterogeneity.
• Statistical analyses, including multivariable regression, were performed to identify associations between TpTe and phenogroups.

Main Results:

• The TpTe interval was significantly associated with B-type natriuretic peptide levels, QRS-T angle, and septal e' velocity.
• Patients in phenogroup #3, characterized by older age, chronic kidney disease factors, and adverse outcomes, exhibited the greatest TpTe duration.
• Increased TpTe duration was independently associated with classification into the high-risk phenogroup #3.

Conclusions:

• Repolarization heterogeneity, as indicated by the TpTe interval, is significantly elevated in a specific high-risk subset of HFpEF patients.
• This finding suggests that repolarization heterogeneity may serve as a key pathophysiological marker for phenogroup #3 in HFpEF.
• Machine learning-derived phenotyping combined with ECG parameters offers valuable insights into HFpEF heterogeneity.