Assessment of left ventricular preload by cardiac magnetic resonance imaging predicts exercise capacity in adult operated tetralogy of Fallot: a retrospective study.
BMC Cardiovasc Disord
; 14: 122, 2014 Sep 23.
Article
em En
| MEDLINE
| ID: mdl-25245139
ABSTRACT
BACKGROUND:
The optimal timing of pulmonary homograft valve replacement (PVR) is uncertain. Cardiopulmonary exercise testing (CPET) and cardiac magnetic resonance (CMR) are often used to guide the clinical decision for PVR in operated tetralogy of Fallot (TOF) patients with significant pulmonary regurgitation (PR). We aim to study the relationship between exercise capacity and CMR in these patients.METHODS:
The study is a single-centre retrospective analysis of 36 operated TOF patients [median 21.4 (interquartile range 16.4, 26.4) years post-repair; 30 NYHA I, 6 NYHA II; median age 25.2 (interquartile range 19.5-31.7) years, 29 males] with significant PR on CMR who underwent CPET within 15 [median 2.0 (interquartile range 0.8-7.2)] months from CMR. CPET parameters were compared with 30 age- and sex-matched healthy controls [median age 27.8 (interquartile range 21.0-32.8) years; 24 males].RESULTS:
Peak systolic blood pressure (177 versus 192 mmHg, p = 0.007), Mets (7.3 versus 9.9, p < 0.001), peak oxygen consumption (VO2max) (29.2 versus 34.5 ml/kg/min, p < 0.001) and peak oxygen pulse (11.0 versus 13.7 ml/beat, p = 0.003) were significantly lower in TOF group versus control. Univariate analyses showed negative correlation between PR fraction and anaerobic threshold. There was a positive correlation between indexed left (LV) and right (RV) ventricular end-diastolic volumes, as well as indexed LV and effective RV stroke volumes, on CMR and VO2max and Mets achieved on CPET. These remained significant after adjustment for age and sex.CONCLUSIONS:
TOF subjects have near normal exercise capacity but significantly lower Mets, VO2max and peak oygen pulse achieved compared to controls. Increased PR fraction in TOF subjects was associated with lower anaerobic threshold. Higher indexed effective RV stroke volume, a measure of LV preload, was associated with higher VO2max and Mets achieved, and may potentially be used as a predictor of exercise capacity.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Insuficiência da Valva Pulmonar
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Tetralogia de Fallot
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Função Ventricular Esquerda
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Tolerância ao Exercício
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Imagem Cinética por Ressonância Magnética
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Procedimentos Cirúrgicos Cardíacos
Tipo de estudo:
Diagnostic_studies
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Etiology_studies
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Observational_studies
/
Prognostic_studies
/
Risk_factors_studies
Limite:
Adolescent
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Adult
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Female
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Humans
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Male
País como assunto:
Asia
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article