a) Calcified Aortic Stenosis
· Congenitally bicuspid or unicuspid, fused commissures, heavy calcification, age 50-70
b) Rheumatic Aortic Stenosis
· Fibrous thickening, 3-cusp valve, mild calcification, rheumatic fever history in 1/2
c) Degenerative Aortic Stenosis
· Diffuse nodular calcification, 3-cusp valve, no commissural fusion
· Cusp prolapse or cicatricial shortening of cusps with rolled edges
· Annulo-aortic ectasia is a disease of the aorta rather than the valve itself
· Dilation of sinus aorta, cystic medial necrosis, failure of coaptation of cusps
a) Aortic Stenosis
· Dyspnea, angina, syncope in 1/3
· Angina more common with CAD
· Severe AS = LV to Ao gradient greater than 50 mmHg or aortic valve area less than 1.2 cm2/M2
b) Aortic Incompetence
· CHF symptoms, angina 1/4, syncope rare
· Severe AI = LV enlargement, calculated LV end systolic pressure greater than 50mm Hg, EF less than 40%, calculated fiber shortening less than 0.6 cm/sec
a) Hemodynamically severe, symptomatic or asymptomatic
· Sudden death risk high
· Immediate operation is indicated
b) Hemodynamically mild or moderate, asymptomatic
· 50% event free for 4 years
· Operation is not urgent, but patients should be followed carefully as the disease advances rapidly
c) Hemodynamically mild or moderate, symptomatic
· One-third will die within 4 years
· Prompt operation is indicated
a) Latent period to cardiac decompensation is long
· Sudden death is not common
· Once deterioration begins, the LV fails rapidly
b) Symptomatic patient with CHF, angina, syncope
· Prompt operation is indicated
c) Asymptomatic patient
· Follow carefully for LV enlargement or decreased LV function by ECHO or MUGA
· Operate at an appropriate time
· Treat significant coronary artery disease at the time of surgery even if asymptomatic
· CABG reduces risk of AVR and improves long-term survival
· Coronary angiography is indicated in all patients older than 45 years who will be having AVR
· AVR may improve LV performance
· Pre-op LV dysfunction is the strongest predictor of post-op dysfunction (60%)
· Microscopic changes in myocardium may persist despite improvement in symptoms and reduction in heart size
· Advanced age most common predictor of survival and cardiac events
· AVR very effective treatment even in patients over age 70 or 80
· Even the best patients over age 80 have reduced reserve
· Age less than 55 years - Aortic allograft or pulmonary autograft
· Age between 55-75 years - Mechanical prosthesis
· Age greater than 75 years - Porcine heterograft, stented or stentless
· Allografts and autografts enlarge the orifice by about 2 mm, porcine heterografts reduce valve size by about 2 mm, and mechanical valves reduce valve size by about 5-8 mm
a) 19 mm
· Prohibitively high LV/Ao gradient
· Enlarge the aortic root or perform Ross procedure instead
b) 21 mm
· Adequate size if BSA 1.5-1.7 M2 and patient is sedentary
· If BSA greater than 1.7 M2 = enlarge the aortic root (10 year survival 80% vs 60%)
c) 23 mm or larger
· Acceptable LV/Ao gradient in all patients
a) Early (hospital) death - 3-6%
b) Time-related survival
· 5 years - 75%
· 10 years - 60%
· 15 years - 40%
c) Mode of death
· Early due to CHF, hemorrhage, infection, CVA
· Sudden - 20%
· Device related - 20%
· Advanced age
· Functional status (NHYA class)
· Depressed LV function (aortic incompetence)
· Coronary artery disease
· Presence of endocarditis
· Aneurysm of ascending aorta
· Mismatch of prosthesis and body size