Correlation of Auscultatory Severity of Aortic Stenosis With Trans Thoracic Echocardiography

Study Overview
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Brief Summary
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According to the 2006 ACC/AHA practice guidelines for valvular heart disease, patients with asymptomatic aortic stenosis(AS) should have screening transthoracic echocardiograms (TTE) performed annually for severe disease, every 1-2 years for moderate disease and every 3-5 years for mild disease. This results in a multitude of screening studies in the investigators patient population. 3M has developed a new stethoscope and phonocardiography software capable of identifying the peak intensity of the AS murmur and tracking it as it moves towards the second heart sound potentially indicating increasing severity of disease. Currently there exists no data to demonstrate that the aortic stenosis acceleration index (ASAI) correlates to disease severity or progression of disease. The ASAI measures the timing of the peak intensity of the systolic murmur and compares it to the total time in systole (S2-x/s2-s1) where s1 is the first heart sound; S2 is the second heart sound and x with the time between S1 and the peak intensity of the murmur. In this study the investigators propose to correlate the ASAI to standard TTE measurements of aortic stenosis severity.

Official Title
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Correlation of Auscultatory Severity of Aortic Stenosis With Trans Thoracic Echocardiography

Conditions
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Aortic Stenosis

Intervention / Treatment
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* Other: Tranthoracic Echocardiogram
* Device: Cardiac Ascultation Recordings with Electronic stethoscope


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male and female subjects 18 years of age and older. Subjects must have asymptomatic Aortic Stenosis documented by prior echocardiographic examination. Subjects must be able to sit for auscultation examination. Subject must be able to complete a TTE . Subjects must voluntarily agree to participate in the study and sign the informed consent and healthcare information authorization forms. Exclusion Criteria: Subjects with significant additional valvular heart disease. Subjects with unrecordable heart sounds. Subjects with known or who may have been previously diagnosed with congenital heart disease. Subjects with atrial fibrillation. Subjects with history of cardiac surgery. Subjects who have conditions which the researcher feels may limit the recordability of the heart sounds or the accuracy of the echocardiogram.

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Aortic stenosis patients<br>Patients with varying degrees of aortic stenosis without significant additional valvular disease will be considered eligible for this study. All participants will recieve a transthoracic echocardiogram and recorded cardiac auscultation. | Other: Tranthoracic Echocardiogram<br>* standard measurement<br>Device: Cardiac Ascultation Recordings with Electronic stethoscope<br>* 3M device<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Aortic Stenosis Acceleration Index Compared to Aortic Stenosis Severity | The ASAI measures the timing of the peak intensity of the systolic murmur and compares it to the total time in systole (S2-x/s2-s1) where s1 is the first heart sound; S2 is the second heart sound and x with the time between S1 and the peak intensity of the murmur. Aortic Stenosis severity will be measured by peak and mean aortic valve gradients as well as aortic valve area derived from the continuity equation. ASAI was averaged and compared to the mean aortic gradient. ROC curve was calculated for ASAI predicting a mean gradient of >30mmHg. ASAI of 34 was determined to provide the optimal combination of specificity and sensitivity and therefore set as the cut off point for significant Aortic Stenosis. | There is a single measurement taken on the day of enrollment. The ascultatory recording and echocardiogram will occur at the same visit. There will be no additional visits or study followup. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Auscultation, Aortic stenosis, computer assisted auscultation, Aortic Stenosis Acceleration Index