Detection of T wave beta-to-beat variations prior to ventricular arrythmias onset in ICD-stored intracardiac electrograms: the endocardial T-wave alternans study (ETWAS)

Philippe Maury (1) , Chao Lin (2, 3) , Jean Luc Pasquié (4) , Franck Raczka (4) , Jérôme Taieb (5) , Corinne Mailhes (2) , Jean-Yves Tourneret (6, 7) , Anne Rollin (1) , Alexandre Duparc (1) , Pierre Mondoly (1) , Pierre Winum (8) , Philippe Rolland (9) , Francis Castanié (3)

1 CHU Toulouse - Centre Hospitalier Universitaire de Toulouse
2 IRIT-SC - Signal et Communications
3 TéSA - Télécommunications Spatiales et Aéronautiques - Telecommunications for Space ant Aeronautics
4 Hôpital Arnaud de Villeneuve [CHRU Montpellier]
5 Centre Hospitalier du Pays d'Aix
6 IRIT-MINDS - CoMputational imagINg anD viSion
7 Toulouse INP - Institut National Polytechnique (Toulouse)
8 CHU Nîmes - Centre Hospitalier Universitaire de Nîmes
9 St Jude Medical

Background: The aim of the Endocardial T-Wave Alternans Study was to prospectively assess thepresence of T-wave alternans (TWA) or beat-to-beat repolarization changes on implantable cardioverter-defibrillator (ICD)-stored electrograms (EGMs) immediately preceding the onset of spontaneous ventriculartachycardia (VT) or fibrillation (VF). Methods: Thirty-seven VT/VF episodes were compared to 116 baseline reference EGMs from the same57 patients. A Bayesian model was used to estimate the T-wave waveform in each cardiac beat and a setof 10 parameters was selected to segment each detected T wave. Beat-by-beat differences in each T-waveparameter were computed using the absolute value of the difference between each beat and the followingone. Fisher criterion was used for determining the most discriminant T-wave parameters, then top-Mranked parameters yielding a normalized cumulative Fisher score>95% were selected, and analysis wasapplied on these selected parameters. Simulated TWA EGMs were used to validate the algorithm. Results: In the simulation study, TWA was detectable even in the case of the smallest simulatedalternans of 25μV. In 13 of the 37 episodes (35%) occurring in nine of 16 patients, significant largerbeat-to-beat variations before arrhythmia onset were detected compared to their respective references(median one positive episode per patient). Parameters including the T-wave apex amplitude seem themore discriminant parameters.Conclusions:Detection of beat-by-beat repolarization variations in ICD-stored EGMs is feasible ina significant subset of cases and may be used for predicting the onset of ventricular arrhythmias.

Mots clés: wave alternans; sudden death; implantable cardioverter defibrillator; intracardiac electrogram; ventricular tachycardia

Domaines: Informatique [cs]

Philippe Maury, Chao Lin, Jean Luc Pasquié, Franck Raczka, Jérôme Taieb, et al.. Detection of T wave beta-to-beat variations prior to ventricular arrythmias onset in ICD-stored intracardiac electrograms: the endocardial T-wave alternans study (ETWAS). PACE - Pacing and Clinical Electrophysiology, 2014, 37 (11), pp.1510--1519. ⟨10.1111/pace.12453⟩. ⟨hal-03263723⟩