Spatial repolarization heterogeneity and survival in Chagas disease

Area of Science:

• Cardiology
• Electrophysiology
• Chagas Disease Research

Background:

• Chronic Chagas disease poses significant cardiovascular risks.
• Assessing mortality risk in Chagas disease patients is crucial for clinical management.
• Cardiac repolarization heterogeneity is an emerging area of interest for cardiovascular risk stratification.

Purpose of the Study:

• To investigate the association between cardiac spatial repolarization heterogeneity and mortality risk in patients with chronic Chagas disease.
• To evaluate the prognostic value of the V-index, a novel metric for repolarization heterogeneity, in this patient population.

Main Methods:

• Utilized the V-index, derived from a biophysical electrocardiogram (ECG) model, to quantify repolarization heterogeneity.
• Analyzed data from 113 patients with chronic Chagas disease (positive for Trypanosoma cruzi) followed for 10 years.
• Employed univariate and multivariate Cox proportional-hazards analyses, including shrinkage for over-fitting protection.

Main Results:

• The V-index was significantly lower in survivors compared to non-survivors (p=0.009).
• A V-index greater than 36.3 ms was associated with a 5.34-fold increased risk of death (p=0.0046).
• The V-index retained its prognostic significance even after adjusting for established risk factors like ejection fraction and ventricular tachycardia.

Conclusions:

• Increased cardiac repolarization dispersion, as indicated by a higher V-index, is a significant predictor of mortality in chronic Chagas disease.
• The V-index provides prognostic information not captured by conventional risk factors.
• This metric holds potential for improving risk stratification and guiding clinical decisions in Chagas disease management.