Importance of over-reading ambulatory ECG-based microvolt T-wave alternans to eliminate three main sources of measurement error.
Ann Noninvasive Electrocardiol
; 24(5): e12670, 2019 09.
Article
en En
| MEDLINE
| ID: mdl-31241245
BACKGROUND: Ambulatory electrocardiogram (ECG)-based microvolt T-wave alternans values measured by the modified moving average method (MMA-TWA) can be disrupted by T-wave changes that mimic true repolarization alternans. METHODS: We investigated potential sources of measurement error by studying 19 healthy subjects (12 men; median age, 25) free of known heart disease with 36-month follow-up to establish freedom from significant arrhythmia or syncope. All participants underwent 24-hr continuous 12-lead ECG monitoring. Causes of automated MMA-TWA ≥42 µV episodes were classified based on visual inspection. RESULTS: A total of 2,189 episodes of automated MMA-TWA episodes ≥42 µV were observed in all subjects (peak MMA-TWA: median, 94 µV; interquartile range, 81-112 µV). All episodes included one or more beats with T-wave deformation which lacked "repeating ABAB pattern" and therefore were identified as TWA measurement error. Causes of such error were categorized as: (a) artifact [72.6% (1,589/2,189), observed in 19 (100%) subjects], more frequently in limb than precordial leads; (b) T-wave changes due to changes in heart/body position [25.5% (559/2,189), observed in 14 (73.7%) subjects], frequently observed in leads V1-2; and (c) postextrasystolic T-wave changes [1.9% (41/2,189), observed in 2 (10.5%) subjects]. CONCLUSIONS: Relying only on automated MMA-TWA values obtained during ambulatory ECG monitoring can lead to incorrect measurement of TWA. Our findings offer the potential to reduce false-positive TWA results and to achieve more accurate detection of true repolarization alternans.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Electrocardiografía Ambulatoria
/
Sistema de Conducción Cardíaco
Tipo de estudio:
Diagnostic_studies
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Etiology_studies
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Prognostic_studies
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Risk_factors_studies
Límite:
Adolescent
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Adult
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Child
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Humans
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Middle aged
Idioma:
En
Revista:
Ann Noninvasive Electrocardiol
Asunto de la revista:
CARDIOLOGIA
Año:
2019
Tipo del documento:
Article
País de afiliación:
Japón
Pais de publicación:
Estados Unidos