Measurement of Myocardial Stiffness Using Elastometry in Patients With Aortic Stenosis

Study Overview
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Brief Summary
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Elastography is a new non-invasive medical technique for measuring the stiffness at a distance from a tissue. Recent advances in the development of elastography sequences for cardiac exploration suggest a more clinical approach to cardiac elastography. This study propose to compare myocardial stiffness of a group of coronary bypass patients without hypertrophic left ventricular remodeling or sequelae of myocardial infarction versus a group of patients who should benefit from a surgical aortic valve replacement for aortic stenosis. The hypothesis is that the physiological adaptation to pressure overload constituted by aortic stenosis is responsible for a significant increase in myocardial stiffness compared to a reference group.

Official Title
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Epicardial Measurement of Myocardial Stiffness on Beating Heart and Non-beating Heart During a Programmed Surgical Aortic Valve Replacement for Aortic Stenosis

Conditions
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Aortic Valve Stenosis

Intervention / Treatment
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* Device: Aixplorer Mach30


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Group I (aortic stenosis): 1. Patient undergoing planned surgical aortic valve replacement (SAVR) for aortic stenosis (aortic valve area <1cm² or an aortic valve area index <0.6 cm² / m²); Group II: coronary bypass 2. Patient undergoing planned myocardial revascularization surgery (coronary bypass); Groups I and II 3. Patient over 18 years of age; 4. Patient having read and understood the information letter and having signed the consent form; 5. Patient affiliated or benefiting from a health insurance scheme Exclusion Criteria: Group II: coronary bypass Ratio in TM mode of the wall thickness over the radius of the left ventricle (h / r [0.45]) confirmed by the TTE; Scar of myocardial infarction defined by an ECG anomaly and / or hypo-akinesia on TTE, and / or a late enhancement in MRI; Acute coronary syndrome less than 3 months old; Significant aortic stenosis (Vmax> 1.5 m / s); Anomaly of segmental kinetics; Presence of left ventricular hypertrophy Groups I and II 7. Mitral valve disease (> 1/4 confirmed by TTE); 8. Aortic insufficiency (> 1/4 confirmed by TTE); 9. Left ventricle ejection fraction (LVEF) <50% confirmed by TTE; 10. Hospitalization for heart failure less than 3 months old; 11. Urgent surgery; 12. Infiltrative heart disease; 13. Hostile pericardium defined by a history of mediastinal radiotherapy, tamponade or complicated pericarditis; 14. Decompensated or severe arterial hypertension. 15. Functional inability to walk preventing the performance of the walk test; 16. Proven pregnant woman (positive urine pregnancy test) or breastfeeding or absence of effective contraception (as defined by the WHO) or postmenopausal woman without confirmation diagnosis obtained (amenorrhea not medically induced for at least 12 months before the initiation visit) ; 17. Person deprived of their liberty by an administrative or judicial decision or person placed under the protection of justice / guardianship or curatorship 18. History of illness or psychological or sensory abnormality likely to prevent the subject from fully understanding the conditions required for participating in the protocol or preventing him from giving his informed consent

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Surgical Aortic Valve Replacement<br>Patients with aortic stenosis | Device: Aixplorer Mach30<br>* To measure myocardial stiffness by ShearWave elastography on not beating heart<br>|
| Other: Reference<br>Coronary bypass patients without hypertrophic left ventricular remodeling or sequelae of myocardial infarction | Device: Aixplorer Mach30<br>* To measure myocardial stiffness by ShearWave elastography on not beating heart<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| to compare myocardial stiffness by ShearWave elastography on not beating heart in two groups of patients referred for surgery | The main outcome measure is evaluated by ShearWave elastography with the measurement of Young modulus on non-beating heart | Day 1 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To compare the diastolic myocardial stiffness of the beating heart with the myocardial stiffness of the non-beating heart | This outcome measure is evaluated by ShearWave elastography with the measurement of Young modulus on non-beating heart | Day 1 | 
| To compare epicardial and trans-thoracic diastolic myocardial stiffness | This outcome measure is evaluated by elastography using the measurement of Young modulus in epicardial (using the linear probe) and transthoracic (using the scanning probe). | Day 1 | 
| Correlation between the diastolic myocardial stiffness of the beating heart and the non-beating heart with conventional diastolic indices | This outcome measure is evaluated: by ShearWave elastography with the measurement of Young modulus on non-beating heart by conventional ultrasound criteria (peak e', peak E, volume of the left atrium calculated by simpson biplanes, maximum velocity of tricuspid insufficiency). | Day 1 | 
| Correlation between the diastolic myocardial stiffness of the beating heart and the non-beating heart with heart failure parameters | This outcome measure is evaluated: by ShearWave elastography with the measurement of Young modulus on non-beating heart by heart failure parameters defined by NYHA class, the walking test and the BNP assay | Day 1 | 
| Correlation between the diastolic myocardial stiffness of the beating heart and the non-beating heart with left ventricular mass indexed to the body surface | This outcome measure is evaluated: by ShearWave elastography with the measurement of Young modulus on non-beating heart by LV mass indexed to the body surface calculated by the cardiac mass measuring by ultrasound indexed to the body surface | Day 1 | 
| Correlation between the diastolic myocardial stiffness of the beating heart and the non-beating heart and the prognosis | This outcome measure is evaluated: by ShearWave elastography with the measurement of Young modulus on non-beating heart by a combined index combining all rehospitalization for heart failure, increase in heart failure treatment and cardiac death | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Elastography, Myocardial stiffness, Surgical Aortic Valve Replacement