Clinical Research
Rationale and Design of the Canadian Outcomes Registry Late After Tetralogy of Fallot Repair: The CORRELATE Study

https://doi.org/10.1016/j.cjca.2014.06.011Get rights and content

Abstract

Background

Chronic hemodynamically relevant pulmonary regurgitation (PR) resulting in important right ventricular dilation and ventricular dysfunction is commonly seen after tetralogy of Fallot (TOF) repair. Late adverse clinical outcomes, including exercise intolerance, arrhythmias, heart failure and/or death accelerate in the third decade of life and are cause for considerable concern. Timing of pulmonary valve replacement (PVR) to address chronic PR is controversial, particularly in asymptomatic individuals, and effect of PVR on clinical measures has not been determined.

Methods

Canadian Outcomes Registry Late After Tetralogy of Fallot Repair (CORRELATE) is a prospective, multicentre, Canada-wide cohort study. Candidates will be included if they are ≥ 12 years of age, have had surgically repaired TOF resulting in moderate or severe PR, and are able to undergo cardiovascular magnetic resonance imaging. Enrollment of > 1000 individuals from 15 participating centres (Toronto, Montreal, Quebec City, Sherbrooke, Halifax, Calgary, Edmonton, and Vancouver) is anticipated. Clinical data, health-related quality of life metrics, and adverse outcomes will be entered into a web-based database. A central core lab will analyze all cardiovascular magnetic resonance studies (PR severity, right ventricular volumes, and ventricular function). Major adverse outcomes (sustained ventricular tachycardia and cardiovascular cause of death) will be centrally adjudicated.

Results

To the best of our knowledge, CORRELATE will be the first prospective pan-Canadian cohort study of congenital heart disease in children and adults.

Conclusions

CORRELATE will uniquely link clinical, imaging, and functional data in those with repaired TOF and important PR, thereby enabling critical evaluation of clinically relevant outcomes in those managed conservatively compared with those referred for PVR.

RÉSUMÉ

Introduction

Une régurgitation pulmonaire (RP) chronique pertinente sur le plan hémodynamique qui entraîne une importante dilatation ventriculaire droite et une dysfonction ventriculaire est fréquemment observée après la réparation de la tétralogie de Fallot (TF). Les résultats cliniques défavorables tardifs, à savoir l’intolérance à l’effort, les arythmies, l’insuffisance cardiaque ou la mort s’accélèrent au cours de la troisième décennie de la vie et sont la cause de problèmes considérables. Le moment du remplacement valvulaire pulmonaire (RVP) pour lutter contre la RP chronique est controversé, particulièrement chez les individus asymptomatiques. De plus, l’effet du RVP sur les mesures cliniques n’a pas été déterminé.

Méthodes

L’étude CORRELATE (Canadian Outcomes Registry Late After Tetralogy of Fallot Repair) est une étude de cohorte prospective et multicentrique pancanadienne. Les candidats seront sélectionnés s’ils ont ≥ 12 ans, ont subi une réparation chirurgicale de la TF entraînant une RP modérée ou grave, et sont aptes à subir une imagerie cardiovasculaire par résonance magnétique. L’inscription de > 1000 individus de 15 centres participants (Toronto, Montréal, Québec, Sherbrooke, Halifax, Calgary, Edmonton et Vancouver) est anticipée. Les données cliniques, les mesures de la qualité de vie liée à la santé et les résultats défavorables seront entrés dans la base de données en ligne. Un laboratoire central analysera toutes les études cardiovasculaires par résonance magnétique (gravité de la RP, les volumes du ventricule droit et a fonction ventriculaire). Les résultats défavorables majeurs (tachycardie ventriculaire soutenue et cause cardiovasculaire de décès) seront centralement confirmés.

Résultats

À notre connaissance, l’étude CORRELATE sera la première étude de cohorte prospective pancanadienne sur la cardiopathie congénitale chez les enfants et les adultes.

Conclusions

L’étude CORRELATE reliera uniquement les données cliniques, fonctionnelles et d’imagerie des individus ayant subi une réparation de la TF et une importante RP, permettant ainsi l’évaluation critique des résultats cliniquement pertinents des individus qui sont pris en charge de manière conservatrice comparativement à ceux qui sont orientés pour subir le RVP.

Section snippets

Rationale

Optimal timing of PVR to address chronic important PR in the asymptomatic individual is considered one of the most important, but as yet unresolved, questions in contemporary CHD practice worldwide.16, 17 In the left heart, prospective cohort data were used to define an inflection point in the natural history of chronic asymptomatic clinically relevant aortic regurgitation, where risk of death exceeds the risk of surgery and the case for intervention is clearly made.18 In contrast to the wealth

Study design

The CORRELATE study is a multicentre, prospective cohort study involving 15 clinical centres in 8 Canadian cities. These sites encompass the largest pediatric cardiology and adult congenital cardiac programs in the country (Supplemental Fig. S1 and Supplementary Table S1 in the Supplementary Material). Candidates ≥ 12 years of age will be eligible for inclusion if ≥ moderate residual PR exists (regurgitation fraction ≥ 25% using CMR or flow reversal in the PAs on echocardiography) after TOF

Results

To the best of our knowledge, CORRELATE is the first large, prospective, multi-centre registry of children and adults after TOF repair to be established in North America.

Discussion

CORRELATE will assemble clinical, imaging, and functional data in a large, unselected, pan-Canadian cohort living with the sequelae of chronic PR after early TOF repair. Prospective enrollment will allow for ongoing, detailed analysis of clinical status, with specific focus on evaluation of symptoms and measurement of HR-QOL at various time points before and after PVR. We anticipate that candidates will be evaluated at regular intervals and we will ensure that relevant clinical outcomes are

Conclusions

CORRELATE is a pan-Canadian, multicentre, cohort study of children and adults with chronic PR after early TOF repair. CORRELATE will uniquely link clinical, imaging, and functional data to evaluate clinically relevant outcomes in those managed conservatively compared with those referred for PVR. Specific emphasis will be placed on the effect of PVR on clinical measures of well-being and adverse outcomes.

Funding Sources

The CORRELATE study is funded by the Canadian Institutes of Health Research (MOP 119353).

Disclosures

The authors have no conflicts of interest to disclose.

References (34)

Cited by (0)

See page 1442 for disclosure information.

These authors contributed equally to this work.

View full text