Marked exercise-induced T-wave heterogeneity in symptomatic diabetic patients with nonflow-limiting coronary artery stenosis.
Ann Noninvasive Electrocardiol
; 23(2): e12503, 2018 Mar.
Article
em En
| MEDLINE
| ID: mdl-28949056
BACKGROUND: T-wave heterogeneity (TWH) independently predicted cardiovascular mortality in Health Survey 2000 based on 12-lead ECGs recorded at rest. We investigated whether TWH is elevated during exercise tolerance testing (ETT) in symptomatic diabetic patients with nonflow-limiting coronary artery stenosis compared to control subjects without diabetes. METHODS: Cases were all patients (n = 20) with analyzable ECG recordings during both rest and ETT who were enrolled in the Effects of Ranolazine on Coronary Flow Reserve (CFR) in Symptomatic Patients with Diabetes and Suspected or Known Coronary Artery Disease (RAND-CFR) study (NCT01754259); median CFR was 1.44; 80% of cases had CFR <2. Control subjects (n = 9) were nondiabetic patients who had functional flow reserve (FFR) >0.8, a range not associated with inducible ischemia. TWH was analyzed from precordial leads V4 , V5 , and V6 by second central moment analysis, which assesses the interlead splay of T-waves about a mean waveform. RESULTS: During exercise to similar rate-pressure products (p = .31), RAND-CFR patients exhibited a 49% increase in TWH during exercise (rest: 49 ± 5 µV; exercise: 73 ± 8 µV, p = .003). By comparison, in control subjects, TWH was not significantly altered (rest: 52 ± 11 µV; ETT: 38 ± 5 µV, p = .19). ETT-induced ST-segment depression >1 mm (p = .11) and Tpeak -Tend (p = .18) and QTc intervals (p = .80) failed to differentiate cases from controls. CONCLUSIONS: TWH is capable of detecting latent repolarization abnormalities, which are present during ETT in diabetic patients with nonflow-limiting stenosis but not in control subjects. The technique developed in this study permits TWH analysis from archived ECGs and thereby enables mining of extensive databases for retrospective studies and hypothesis testing.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Circulação Coronária
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Estenose Coronária
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Diabetes Mellitus
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Eletrocardiografia
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Teste de Esforço
Tipo de estudo:
Clinical_trials
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Diagnostic_studies
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Etiology_studies
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Observational_studies
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Prognostic_studies
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Risk_factors_studies
Limite:
Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Ann Noninvasive Electrocardiol
Assunto da revista:
CARDIOLOGIA
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Estados Unidos