Effect of Contouring Techniques on CMR Assessment of the Right Ventricle in Repaired Tetraology of Fallot

Study Overview
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Brief Summary
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Patients with repaired tetralogy of Fallot (RTOF) develop chronic pulmonary regurgitation and require monitoring for right ventricular dilatation. Pulmonary valve replacement can prevent irreversible right ventricular (RV) dilatation and dysfunction and cardiac magnetic resonance (CMR) is used to facilitate its optimal timing. The investigators sought to determine whether the choice of myocardial contouring technique affects preoperative RV volumetric thresholds for intervention.

Detailed Description
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Participants with repaired tetralogy of Fallot (RTOF) will be identified using existing patient electronic records who have developed chronic pulmonary regurgitation and are undergoing monitoring for right ventricular dilatation. Cardiac magnetic resonance (CMR) is used to facilitate its optimal timing. Pulmonary valve replacement can prevent irreversible right ventricular (RV) dilatation and dysfunction and cardiac magnetic resonance (CMR) is used to facilitate its optimal timing. There are different post-processing techniques published for measuring RV volumes on cardiac magnetic resonance imaging (detailed vs. smoothed and manual vs. automated). The primary aim of this study is to identify whether the choice of myocardial contouring technique affects the preoperative RV volumetric thresholds for intervention. As a secondary aim, the investigators will determine the reproducibility of different contouring methods.

Official Title
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The Effect of Different Contouring Techniques on Cardiac Magnetic Resonance Assessment of Right Ventricular Volumes in Repaired Tetraology of Fallot: Implications on Preoperative Thresholds for Intervention

Conditions
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Tetralogy of Fallot

Intervention / Treatment
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* Diagnostic Test: Cardiac MRI


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Consecutive patients with repaired Tetralogy of Fallot undergoing routine clinical surveillance at a Level 1 ACHD surgical referral centre. Exclusion Criteria: None

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Repaired Tetralogy of Fallot<br>Patients undergoing routine clinical aand CMR surveillance | Diagnostic Test: Cardiac MRI<br>* For clinical surveillance<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference in the baseline measurement of indexed right ventricular end-diastolic volume according to the contouring technique | Measurements of indexed right ventricular end-diastolic volume will be repeated using different contouring techniques on the same cardiac MRI study performed at baseline pre-surgery. | Cross-sectional study. Repeated measurements performed on the baseline CMR study. |