Right Bundle Branch Block After Surgical Closure of Ventricular Septal Defect

Study Overview
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Brief Summary
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The most common congenital heart disease is the ventricular septal defect, and after surgical closure of a such defect, an arrythmia called the right bundle branch block, is very frequent. Therefore the aim of this study is to investigate if this group of patients has inferior outcomes compared to the group without this arrythmia after surgical closure and compared to a group of healthy control subjects. All patients will be undergoing 1. exercise testing, 2. echocardiography, 3. echocardiography during exercise, and 4. MRI. The perspective is the ability to point out a group of patients with a possible need of further intervention, and additionally to increase the awareness of protecting the electrical system of the heart during the operation.

Detailed Description
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Right bundle branch block is an exceedingly frequent complication in heart surgery, and especially in patients who have undergone surgical closure of a ventricular septal defect which is the most common congenital heart disease. How this bundle branch block effects the right ventricle of the heart on a long-term basis for this group of patients, is still unknown. As a part of a PhD-study we therefore will try to illustrate this by echocardiography, MRI, exercise testing and other investigations 15 to 20 years after the surgical procedure. The study population thus consists of three different groups: 1. Patients whom undergone surgical closure of ventricular septal defect without postoperative right bundle branch block, 2. VSD-operated patients with right bundle branch block and 3. Healthy controls with no significant medical issues matched on age and sex. By carrying out the tests mentioned the right ventricles systolic function, diastolic function, the patients maximal exercise capacity and a lot of other parameters will be evaluated in the three groups of patients and compared amongst each other. The perspective therefore is the ability to point out a specific group of patients with an inferior outcome and with a possible need for further intervention. An additional perspective is to increase the awareness of protecting the bundle branch during the operation.

Official Title
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Postoperative Right Bundle Branch Block - Long-term Effect on the Right Ventricle in Children Operated for Ventricular Septal Defect

Conditions
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Bundle-Branch Block, Heart Septal Defects, Ventricular

Intervention / Treatment
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* Procedure: Echocardiography at rest
* Procedure: Echocardiography during exercise
* Procedure: MRI at rest
* Procedure: Exercise testing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Operated for VSD in the period from 1990 to 1995 on Aarhus University Hospital Skejby Exclusion Criteria: No chart to be found No EKG to be found Known bundle branch block prior to the surgery Other arrythmias Use of ventriculotomy Other disease than VSD Pacemaker or other metallic implants Pregnancy
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: VSD, +Right bundle branch block<br>Patients undergone surgical closure of ventricular septal defect and have a postoperative right bundle branch block, about 20 patients | Procedure: Echocardiography at rest<br>* Dimensions of all 4 chambers, inspiratory collapse, and gradient over the tricuspid valve is measured. Tricuspid Annulus Plane Systolic Excursion(TAPSE) and Tricuspid Annular peak Systolic Motion(TASM) is measured as well.<br>Procedure: Echocardiography during exercise<br>* TASM is measured during exercise along with pulse measurements to evaluate the force-frequency-relation.<br>Procedure: MRI at rest<br>* Dimensions of all 4 chambers are measured at end-systole and end-diastole. Blood flow measurements through the aortic and the pulmonary valve are made as well. No use of contrast.<br>Procedure: Exercise testing<br>* Maximal oxygen consumption is measured during on a bicycle. Prior to the test a spirometry is performed to rull out potential differences in pulmonary function between the cohorts. During the test pulse, blood pressure, saturation, and EKG are monitored. Ventilatory volume, oxygen consumption and carbon dioxide excretion are measured. Anaerobic threshold is calculated at the end of the test.<br>|
| Experimental: VSD, -Right bundle branch block<br>Patients undergone surgical closure of ventricular septal defect and does not have a postoperative right bundle branch block, about 20 patients | Procedure: Echocardiography at rest<br>* Dimensions of all 4 chambers, inspiratory collapse, and gradient over the tricuspid valve is measured. Tricuspid Annulus Plane Systolic Excursion(TAPSE) and Tricuspid Annular peak Systolic Motion(TASM) is measured as well.<br>Procedure: Echocardiography during exercise<br>* TASM is measured during exercise along with pulse measurements to evaluate the force-frequency-relation.<br>Procedure: MRI at rest<br>* Dimensions of all 4 chambers are measured at end-systole and end-diastole. Blood flow measurements through the aortic and the pulmonary valve are made as well. No use of contrast.<br>Procedure: Exercise testing<br>* Maximal oxygen consumption is measured during on a bicycle. Prior to the test a spirometry is performed to rull out potential differences in pulmonary function between the cohorts. During the test pulse, blood pressure, saturation, and EKG are monitored. Ventilatory volume, oxygen consumption and carbon dioxide excretion are measured. Anaerobic threshold is calculated at the end of the test.<br>|
| Experimental: Control<br>Healthy control subjects, about 20 patients | Procedure: Echocardiography at rest<br>* Dimensions of all 4 chambers, inspiratory collapse, and gradient over the tricuspid valve is measured. Tricuspid Annulus Plane Systolic Excursion(TAPSE) and Tricuspid Annular peak Systolic Motion(TASM) is measured as well.<br>Procedure: Echocardiography during exercise<br>* TASM is measured during exercise along with pulse measurements to evaluate the force-frequency-relation.<br>Procedure: MRI at rest<br>* Dimensions of all 4 chambers are measured at end-systole and end-diastole. Blood flow measurements through the aortic and the pulmonary valve are made as well. No use of contrast.<br>Procedure: Exercise testing<br>* Maximal oxygen consumption is measured during on a bicycle. Prior to the test a spirometry is performed to rull out potential differences in pulmonary function between the cohorts. During the test pulse, blood pressure, saturation, and EKG are monitored. Ventilatory volume, oxygen consumption and carbon dioxide excretion are measured. Anaerobic threshold is calculated at the end of the test.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Systolic function at rest measured by echocardiography | Dimensions of all 4 chambers, inspiratory collapse, and gradient over the tricuspidale valve is measured. Tricuspid Annulus Plane Systolic Excursion(TAPSE) and Tricuspid Annular peak Systolic Motion(TASM) is measured as well. | All patients are tested only once about 20 years post to surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maximal oxygen consumption during exercise | Maximal oxygen consumption is measured during on a bicycle. Prior to the test a spirometry is performed to rull out potentiel diffenrences in pulmonary function between the cohorts. During the test pulse, blood pressure, saturation, and EKG are monitored. Ventilatory volume, oxygen consumption and carbondioxide excretion are measured. Anaerobic threshold is calculated at the end of the test. | All patients are tested only once about 20 years post to surgery | 
| Force-frequency-relation during exercise | TASM is measured during exercise along with pulse measurements to evaluate the force-frequency-relation. | All patients are tested only once about 20 years post to surgery | 
| Diastolic function at rest measured by MRI | Dimensions of all 4 chambers are measured at end-systole and end-diastole. Blood flow measurements through the aortic and the pulmonary valve are made as well. No use of contrast. | All patients are tested only once about 20 years post to surgery | 
| Diastolic function at rest measured by echocardiography | Dimensions of all 4 chambers, inspiratory collapse, and gradient over the tricuspidale valve is measured. Tricuspid Annulus Plane Systolic Excursion(TAPSE) and Tricuspid Annular peak Systolic Motion(TASM) is measured as well. | All patients are tested only once about 20 years post to surgery | 
| Systolic function at rest measured by MRI | Dimensions of all 4 chambers are measured at end-systole and end-diastole. Blood flow measurements through the aortic and the pulmonary valve are made as well. No use of contrast. | All patients are tested only once about 20 years post to surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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MRI, Right bundle branch block, Ventricular septal defect, Echocardiography, Exercise testing