Use of the 6-min walk distance to identify variations in treatment benefits from implantable cardioverter-defibrillator and amiodarone: results from the SCD-HeFT (Sudden Cardiac Death in Heart Failure Trial).
J Am Coll Cardiol
; 63(23): 2560-2568, 2014 Jun 17.
Article
em En
| MEDLINE
| ID: mdl-24727258
ABSTRACT
OBJECTIVES:
The purpose of this study was to determine if 6-min walk test data assists in treatment decisions for patients with heart failure.BACKGROUND:
In the SCD-HeFT (Sudden Cardiac Death in Heart Failure Trial), a pre-specified subgroup analysis showed that patients with New York Heart Association functional class III symptoms did not benefit from implantable cardioverter-defibrillator (ICD) therapy and appeared to be harmed by amiodarone, whereas New York Heart Association functional class II patients obtained significant survival benefit from ICD. We postulated that a more objective measure of functional capacity, such as 6-min walk (6MW) distance, might provide a better tool for selecting these preventive therapies.METHODS:
A 6MW test was performed before randomization in 2,397 patients. Median follow-up was 45.5 months. All-cause mortality was the primary endpoint, with cause-specific mortality (heart failure, arrhythmic) examined in secondary analyses.RESULTS:
The hazard ratios (HRs) for ICD therapy compared to placebo were estimated within tertiles of baseline 6MW distance HR 0.42 (95% confidence interval [CI] 0.26 to 0.66) for 6MW distance >386 m (top tertile); HR 0.57 (95% CI 0.39 to 0.83) for 6MW distance 288 to 386 m (middle tertile); and HR 1.02 (95% CI 0.75 to 1.39) for 6MW distance <288 m (bottom tertile). The corresponding HRs for amiodarone compared to placebo were 0.68 (95% CI 0.46 to 1.02) for the top, 0.86 (95% CI 0.61 to 1.21) for the middle, and 1.56 (95% CI 1.17 to 2.09) for the bottom tertile. The 6MW distance was inversely related to heart failure-related mortality but not to arrhythmic mortality. ICD therapy reduced arrhythmic mortality in the top 2 tertiles of 6MW, but had no effect on heart failure mortality.CONCLUSIONS:
A baseline 6MW distance <288 m identified a subgroup of SCD-HeFT patients who were harmed by amiodarone therapy and did not benefit from ICD. (Sudden Cardiac Death in Heart Failure Trial [SCD-HeFT]; NCT00000609).Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Caminhada
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Morte Súbita Cardíaca
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Tolerância ao Exercício
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Desfibriladores Implantáveis
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Teste de Esforço
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Insuficiência Cardíaca
/
Amiodarona
Tipo de estudo:
Clinical_trials
/
Observational_studies
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Prognostic_studies
/
Risk_factors_studies
Limite:
Aged
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Female
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Humans
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Male
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Middle aged
País/Região como assunto:
America do norte
Idioma:
En
Revista:
J Am Coll Cardiol
Ano de publicação:
2014
Tipo de documento:
Article