1. Congenital Aortic Stenosis
Echo Conference
January 7, 2008
Anne B. Riley

2. Outline Subvalvular Valvular Supravalvular Morphology Epidemiology/
Genetics
Clinical Presentation
Associated syndromes
Treatment options

3. Subvalvular:Morphology
Caused by an accumulation of fibroelastic tissue
Thin, crescent shaped membrane just below the aortic valve
Thick fibromuscular ridge
Tunnel or tubular: long narrow fibromuscular channel along the LVOT

4. Imaging
SUBvalvular
Courtesy: Yale School of Medicine Atlas of Echocardiography

5. Echocardiogram- PLA
SUBvalvular

6. Echocardiogram- 5 Ch
SUBvalvular

7. Epidemiology SUBvalvular Second most common form of Congenital AS
More common in males (67-75% of cases)
Accounts for 8-30% of LVOT obstruction
Isolated SubAS is felt to be an acquired lesion- not seen in newborns
Reports published of familial occurrence (? Morphologic abnormalities of LVOT lead to predisposition for cell proliferation)

8. Clinical Presentation
SUBvalvular
Clinical Presentation
Lesion often found in children/young adults when evaluating for other cardiac defects
Presentation in the adult is usually in evaluation of a heart murmur
Tends to be a progressive lesion
Aortic valve at risk (high velocity jet slams into aortic valve)
Symptoms depend on degree of obstruction: fatigue, dyspnea on exertion, chest pain, syncope
High risk for developing infective endocarditis

9. Clinical Presentation
SUBvalvular
Clinical Presentation
Associated with other defects in 60% of cases
Multilevel LVOT obstruction
VSD
Coarctation of the aorta
PDA
Left superior vena cava
Valvular aortic stenosis

10. Shone Syndrome Left ventricular inflow and outflow obstruction
SUBvalvular
Shone Syndrome
Left ventricular inflow and outflow obstruction
Parachute mitral valve (single pap muscle), supravalvular mitral ring, subaortic stenosis, coarctation
Treated with surgery often in first year of life
15-year survival 89%
Deaths secondary to severe mitral valve disease, need for multiple surgeries
Brown et al. Operative results and outcome in patient with Shone’s anomaly. Ann Thorasic Surgery 2005 April 79(4).

11. SUBvalvular
Evaluation
Echocardiography: assess anatomy, measure gradient with continuous wave doppler
Cardiac cath: further define mechanism and extent of subaortic obstruction (particularly if suspect multiple levels of obstruction)

12. Treatment Definitive therapy: Surgical correction
SUBvalvular
Treatment
Definitive therapy: Surgical correction
Timing is controversial because of high recurrence rate (~20%)
Suggested indications in adults
Peak gradient >50 mmHg, mean gradient >30 mmHg
Progressive mod-severe AR, EF <55%, or
LVESD 50 mm
Symptomatic from obstruction
Membranectomy +/- myomectomy, Konno-Rastan procedure (reconstruct LVOT)
ACC/AHA 2008 Guidelines for Management of Adults with CHD

13. Valvular Aortic Stenosis
Unicuspid,
acommissural
unicommissural
Bicuspid (most common)
Trileaflet valve
Miniature
Dysplastic
Fusion of commissures
Quadricupsid
(usually incompetent, rarely stenotic)

14. Valvular Aortic Stenosis
14 year old boy referred for aortic stenosis and regurgitation
MRI showed …

15. Valvular AS
Unicuspid
Diagnosis and Management of Adult Congenital Heart Disease

16. Case
30 year old Guatemalan man with mild shortness of breath on exertion and harsh holosystolic murmur at left sternal border and systolic murmur heard at base
Echo shows …

19. Echo showed
Quadricuspid aortic valve, mild AI, no AS (peak velocity 1.3 m/s)
Paramembranous VSD
Large secundum atrial septal defect

20. Bicuspid Valve Morphology
Valvular AS
Bicuspid Valve Morphology
Right-Left Commissures
Gives anterior and posterior cusps
RCA and LMCA both from anterior cusp
False raphe also on anterior cusp
Anterior-Posterior Commissures
Gives left and right cusps
RCA from right cusp and LMCA from left cusp
Often have a false raphe, on right cusp
Right-Left Commissures R L N
Courtesy: Yale University School of Medicine Atlas of echocardiography

21. Valvular AS
Bicuspid

22. Valvular AS

23. Valvular AS

24. Valvular AS
Epidemiology
Bicuspid valve accounts for 95% of cases of congenital AS, occurs in 1-2% of general population
More common in males (3:1)
Case reports of familial inheritance of bicuspid valves, tends to be autosomal dominant with variable penetrance

25. Clinical Presentation
Valvular AS
Clinical Presentation
Initially asymptomatic
Restricted motion
Turbulent flow
Abnormal folding
66% develop aortic stenosis
Only 15% of patients have a normally functioning valve in the 5th decade
Scarring, calcification, stenosis, regurgitation

26. Bicuspids and the Aorta
Valvular AS
Bicuspids and the Aorta
Often have abnormalities of the aortic media
Increased risk for dilatation, dissection (5-9x) and rupture of ascending aorta
Previously thought to be secondary to “poststenotic turbulence”
Abnormalities of ascending aorta occur irrespective of degree of stenosis or regurgitation

27. Monitoring and Treatment
Valvular AS
Monitoring and Treatment
Dilated aortic root (>4 cm): yearly imaging of aorta (echo, CT?, MRI?)
Recent data to suggest that ARBs slow the rate of progression of aortic root dilatation in Marfan’s patients
Brooke et al. Angiotensin II Blockade and Aortic root dilation in Marfan’s Syndrome. NEJM 2008

28. Valvular AS
Intervention
Valve replacement surgery indicated for patients with severe stenosis who are symptomatic or are developing LV dysfunction (EF<50%) or LV dilatation
Consider surgery who have moderate stenosis with moderate AR or dilated ascending aorta
Repair/replacement of the ascending aorta when 5 cm or expanding at a rate >5 mm/yr

29. Supravalvular Aortic Stenosis
Least common lesion of the LVOT
Hourglass vs
Diffuse narrowing
Courtesy: Yale University School of Medicine Atlas of Echocardiography

30. Associated Abnormalities
SupraValvular
Associated Abnormalities
Aortic valve leaflets: thickened, redundant, bicuspid
Coronary artery stenosis
Coarctation of the aorta or stenoses of carotid, renal, iliac
Pulmonary artery stenoses

31. Classification Williams syndrome
SupraValvular
Classification
Williams syndrome
Autosomal dominant form without features of Williams syndrome
Sporadic

32. Williams syndrome Affects 1/10,000 individuals Supravalvular AS (70%)
Mental retardation
Elfin facies
Cocktail personality
Renovascular hypertension
Stellate iris
MRI
Mechanisms and treatment of cardiovascular disease in Williams-Beuren syndrome

33. Genetics and Pathology
SupraValvular
Genetics and Pathology
Mutation in or deletion of the elastin gene located on chromosome 7q11.23
Aortic Media is affected:
a reduction of elastic tissue with disorganized elastin fibers
Decreased elasticity, increased shear stress-> smooth muscle hypertrophy and collagen deposition

34. Therapy: Surgery
Surgical enlargement of sinotubular area and ascending aorta
Recommended with symptoms (angina, dyspnea, syncope) or mean pressure gradient of >50mmHg, or peak >70 mmHg
Excision and end-end anastamosis
Patch enlargement of sinotubular junction

35. Thank you

36. Eli (for suggesting this topic) and
Special thanks to
Eli (for suggesting this topic) and
Anne Marie Valente of the BACH program

37. References
Aboulhosn et al. Left Ventricular Outflow Obstruction: Subaortic Stenosis, Bicuspid Aortic Valve, Supravalvuar Aortic Stenosis, and Coarctation of the Aorta. Circulation 2006:114,
Brooke et al. Angiotensin II Blockade and Aortic root dilation in Marfan’s Syndrome. NEJM 2008.
Brown et al. Operative results and outcome in patient with Shone’s anomaly. Ann Thorasic Surgery 2005 April 79(4).
Holt et al. Quadricuspid Aortic Valve with Aortic Insufficiency: case report and review of the literature. J Card Surg 2007: 22,
Pober et al. Mechanisms and Treatment of Cardiovascular Disease in Williams-Beuren syndrome. J of Clin Investigation: 2008:5,
ACC/AHA 2008 Guidelines for Management of Adults with Congenital Heart Disease.
Diagnosis and Management of Adult Congenital Heart Disease. Gazoulis , Elsevier Limited.
The Clinical Recognition of Congenital Heart Disease. Perloff , WB Saunders.
Yale School of Medicine Atlas of Echocardiography