B Phillips, C Perry
B Phillips, C Perry. Quick Review: Asymptomatic Aortic Stenosis. The Internet Journal of Surgery. 2001 Volume 3 Number 2.
Aortic Stenosis is a disease in "evolution" with our past experience varying dramatically from our present-day reality. This is based on several factors including: a change in etiology; an older patient population; and the use of aggressive non-invasive testing.
In General: Aortic Stenosis (AS)
Aortic Stenosis is a disease in
Our past experience varies dramatically from our present-day reality, which is based on several factors:
a. Etiology of A.S. is changing.
b. Pt. population is getting older, while through aggressive non-invasive testing, A.S. is being “discovered” earlier (i.e. incidentally in asymptomatic patient
1 )Used to be recognized at time of symptoms
a) “Early” Symptoms: Angina, Syncope
b) “Late” Symptoms: Dyspnea (LV Failure / CHF)
2) Symptomatic AS – there is
a) Frank et al –
15 symptomatic patients with “severe” A.S., did not have AVR, followed by NIH, .52% dead at 5 years / 90 % dead at 10 years.
b)Kelly et al –
39 symptomatic patients with Mean Gradient of 68, 38% dead at 1 year, 5 of which were ‘sudden cardiac deaths'
3) Now, pt's present with symptoms UNRELATED (in varying degrees) to their A.S. (i.e. angina from CAD), and the “screening” Echo documents a gradient across the valve.
a) Relative Importance?
b) How to treat or follow ?
4) Asymptomatic AS – management is CONTROVERSIAL
a) Pellikka et al –
113 patients with “severe” A.S. (mean age 70), treated medically and followed for a mean of 20 months .33% developed symptoms / 3 cardiac-deaths (but, each death was preceded by 3-4 months of real-symptoms)
b) In fact, Braunwald –
Natural History of Asymptomatic AS
Before we operate on any disease process, we must understand the natural course of events in order to rationally compare treatment options.
128 patients identified in 1994, all asymptomatic with a “stenotic valve” and an AjV of at least 4m/sec
59 females / 69 males,
Mean Age, 60
Mean AjV, 5.0 m/sec
Follow-up on 126 patients
22 patients (w/o symptoms) had AVR, because of Cardiology Referral
106 “study patients” non-surgical.
1) Event-free Survival
1 yr. : 67%
2 yrs. : 56%
3 yrs. : 33%
8 pts died (6 directly from their cardiac disease)
59 pts developed symptoms & required AVR !
2) Multivariate Analysis
The only independent predictor of outcome was the extent of aortic valve calcification.
Age, Sex, HTN, DM, Hypercholesterolemia, and presence/or absence of CAD were NOT significant (in predicting outcome).
3) Aortic Valve Calcification
“Mild” A.S. - Degrees 1 or 2 calcification
“Severe” A.S. - Degrees 3 or 4 calcification
Degrees of Calcification:
1 - no calcifications seen
2 - mildly calcified with small, isolated lesions
3 - moderately calcified with multiple, large lesions
4 - heavily calcified with extensive thickening & involvement of all valve cusps
4) The Rate of Stenotic Progression [ AjV]
An important PROGNOSTIC FACTOR.
in patients with hemodynamically-significant AS, it is relatively safe to delay urgery until symptoms develop.
sudden death may occur [chance < 1%].
death may occur very quickly after the onset of symptoms.
risk of surgery is HIGHER in symptomatic patients than in ASYMPTOMATIC patients.
1.) Degree 3 or 4 Valves, with stable AjV
rapid disease progression can be expected
80 % of patients will require AVR od die within 4 years but elective (“prophylactic”) replacement can not be recommended.
2.) Degree 3 or 4 Valves with AjV > 0.3 m/sec within 1-yr period have an 80 % event rate at 2 yrs (
Should ASYMPTOMATIC AS be operated upon ?
1) Risk of Sudden Death without AVR
a) may occur in the absence of preceding symptoms
b) reported to be up to 3 – 5 %,
c) likely risk is actually less than 1 %,
2) Risk of ongoing irreversible myocardial damage
a) purely theoretical has never been shown
b) spectrum of disease progression
1) LV Hyperplasia
2) LV Hypertrophy
3) Dilated Cardiomyopathy
3) Otto ‘97: “A.S. rapidly progresses in asymptomatic patients which >produces poor overall outcomes”
1) The risk of Surgery, itself:
2) The risk of the Prosthetic Valve
a.) Mechanical: Anticoagulation (
b.) Tissue: Valve Failure over time
so, the basic question remains unanswered & thus, controversial
there has never been a randomized, prospective study evaluating treatment options in Asymptomatic Aortic Stenosis without this, can we ever rationally agree ?