T-wave alternans and left ventricular wall thickness in predicting arrhythmic risk in patients with hypertrophic

Valentina Otja Puntmann1, Yee Guan Yap, William McKenna

  • 1St George's, University of London, London, UK. vpuntmann@hotmail.co.uk

Insights

Regional variations in left ventricular wall thickness (LVWT) are linked to arrhythmias in hypertrophic cardiomyopathy (HCM). Microvolt T-wave alternans (TWA) testing reveals that increased LVWT, particularly in the inferior wall, predicts arrhythmic events in HCM patients.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Medical Imaging

Background:

  • Regional heterogeneity in left ventricular (LV) hypertrophy is implicated in arrhythmic vulnerability in hypertrophic cardiomyopathy (HCM).
  • Microvolt T-wave alternans (TWA) serves as a risk marker for ventricular tachyarrhythmias (VTAs).

Purpose of the Study:

  • To investigate the relationship between LV wall thickness (LVWT) and TWA in HCM patients.
  • To assess TWA as a predictor of arrhythmic events in relation to LVWT.

Main Methods:

  • 157 consecutive HCM patients underwent 2-D echocardiography and TWA-exercise testing.
  • Arrhythmic burden was assessed over a median follow-up of 3.7 years.
  • Multivariate analysis identified predictors of TWA+ outcome.

Main Results:

  • Ventricular tachyarrhythmias (VTAs) were more frequent in positive (TWA+) and indeterminate (NN-TWA) TWA groups compared to negative TWA.
  • TWA+ patients exhibited greater maximal LVWT and LV mass; NN-TWA was linked to increased LV mass.
  • Regional analysis showed greater inferior LVWT in the TWA+ group, correlating with arrhythmic events.

Conclusions:

  • Positive and NN-TWA outcomes correlate with increased LV mass in HCM.
  • TWA+ is associated with maximal and regional LVWT, indicating risk for arrhythmic events.
  • Regional LVWT measurements can complement risk stratification models in HCM.
Abstract

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