Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content +++ KEY FEATURES +++ ESSENTIALS OF DIAGNOSIS ++ Phenotypic and molecular evidence of Williams-Beuren syndrome in 50% Dyspnea on exertion and angina—common Elevated blood pressure in the right arm versus left arm Harsh systolic ejection murmur typical of valvular aortic stenosis Commonly associated are: – Aortic regurgitation – Peripheral pulmonary artery stenosis – Coarctation of the aorta – Mitral regurgitation Anatomy of the lesion and its severity defined by Doppler echocardiography +++ GENERAL CONSIDERATIONS ++ Either localized or diffused narrowing of the ascending aorta beyond the sinuses of Valsalva and the origin of the coronary arteries Equal prevalence in both sexes Accounts for < 5% of fixed forms of congenital left ventricular outflow obstruction Three distinct presentations: – As a feature of Williams-Beuren syndrome (haploinsufficiency of elastin gene (chromosome 7qll.23) with other abnormalities such as peripheral pulmonary artery stenosis, coarctation of the aorta, and stenoses of the origin of other arteries arising from the ascending aorta and arch – As an autosomal dominant familial form with associated peripheral pulmonary artery stenosis – As a sporadic form also with peripheral pulmonary artery stenosis, which is the most common form Three anatomic forms are recognized: – Discrete narrowing just above the ostia of the coronary arteries—the most common – A fibrous diaphragm just distal to the coronary ostia—the next most common – Diffused narrowing—least common Left main coronary artery obstruction may be present Premature coronary atherosclerosis develops in part due to high systolic pressures below the obstruction Angina can result from coronary obstructions or the low diastolic pressure in the coronary arteries due to the supravalvular obstruction +++ CLINICAL PRESENTATION +++ SYMPTOMS AND SIGNS ++ Dyspnea on exertion Angina Symptoms usually develop in childhood +++ PHYSICAL EXAM FINDINGS ++ Phenotypic features of Williams-Beuren syndrome may be present (elfin facies, developmental challenges, and personality disorders) Systolic blood pressure difference between the 2 arms, caused by preferential flow to the brachiocephalic vessels (higher-pressure right arm) Systolic ejection murmur without an ejection sound Murmur of aortic regurgitation often present Murmur of mitral regurgitation may be present Systolic murmurs in the axillae representing peripheral pulmonary artery stenosis may be present Upper and lower extremity pulse differences due to coarctation of the aorta may be present +++ DIFFERENTIAL DIAGNOSIS ++ Valvular aortic stenosis Subvalvular aortic stenosis Hypertrophic obstructive cardiomyopathy Left subclavian artery stenosis +++ DIAGNOSTIC EVALUATION +++ LABORATORY TESTS ++ Molecular diagnosis of Williams-Beuren syndrome +++ ELECTROCARDIOGRAPHY ++ Left ventricular hypertrophy +++ IMAGING STUDIES ++ Two-dimensional echocardiography demonstrates the supravalvular obstruction Continuous-wave Doppler identifies the pressure gradient Color-flow Doppler demonstrates the site of obstruction, ostial obstruction of the coronary arteries, mitral or aortic regurgitation, and coarctation of ... Your Access profile is currently affiliated with [InstitutionA] and is in the process of switching affiliations to [InstitutionB]. Please select how you would like to proceed. Keep the current affiliation with [InstitutionA] and continue with the Access profile sign in process Switch affiliation to [InstitutionB] and continue with the Access profile sign in process Get Free Access Through Your Institution Learn how to see if your library subscribes to McGraw Hill Medical products. Subscribe: Institutional or Individual Sign In Error: Incorrect UserName or Password Username Error: Please enter User Name Password Error: Please enter Password Sign in Forgot Password? Forgot Username? Download the Access App: iOS | Android Sign in via OpenAthens Sign in via Shibboleth You already have access! Please proceed to your institution's subscription. Create a free profile for additional features.