Comprehensive Approach to Aortic Valve Disease Flashcards
What is the primary etiology of aortic stenosis (AS) in developed countries?
Atherosclerosis-like disease
Previously thought to be degenerative, AS is now recognized as an active inflammatory process similar to coronary artery disease (CAD)
What is the similarity between the plaques found in aortic stenosis and coronary artery disease?
Initial plaque of AS resembles coronary plaque
Both conditions exhibit inflammatory features and lipid-laden cores
What role do statins play in the treatment of aortic stenosis?
Tested to retard disease progression
Trials failed due to differences in plaque mechanisms between AS and CAD
What are the histopathologic features of the aortic stenosis valve?
Inflamed with hotter areas infiltrated by lymphocytes
These features are consistent with an inflammatory process
What is a potential future pharmacologic target for aortic stenosis?
Proprotein convertase subtilisin/kexin type 9 (PCSK9)
PCSK9 is involved in the removal of LDL receptors, impacting LDL and LP(a) levels
What percentage of the US population is born with a bicuspid aortic valve?
1–2%
Bicuspid valves may lead to stenosis earlier in life due to increased shear stress
Name at least three causes of aortic stenosis.
- Calcific atherosclerotic disease
- Rheumatic heart disease
- Post radiation
Other causes include carcinoid syndrome, serotonergic drugs, and Paget’s disease
How is bicuspid aortic valve related to aortopathy?
Associated with aortic root or ascending aorta dilatation
More common with joined right and left cusps
What are the two major theories explaining aortic root dilatation in patients with bicuspid aortic valves?
- Genetic predisposition to aortic root dilatation
- Abnormal flow exiting the misshapen aortic valve
Both mechanisms may contribute to the phenomenon
What is the significance of symptoms in patients with aortic stenosis?
Presence of symptoms indicates worse prognosis
Symptomatic patients have a significantly poorer outcome compared to asymptomatic patients
What is the mean pressure gradient between the left ventricle and aorta at an aortic valve area of 1.0 cm²?
25 mmHg
This gradient increases with further stenosis
What is left ventricular hypertrophy (LVH) and how is it triggered in aortic stenosis?
Development of concentric hypertrophy due to pressure overload
This involves the addition of sarcomeres in parallel, leading to increased wall thickness
What are the potential consequences of left ventricular hypertrophy in patients with aortic stenosis?
- Angina
- Heart failure
- Syncope
LVH contributes to impaired coronary blood flow reserve and diastolic filling
What factors contribute to the impaired coronary blood flow reserve in LVH?
- Diminished capillary ingrowth
- Increased LV filling pressure
These factors reduce the pressure gradient for coronary flow
What are the stages of aortic stenosis according to the ACC/AHA Guidelines?
- Stage A: At risk for AS
- Stage B: Progressive AS
- Stage C: Asymptomatic severe AS
- Stage D: Symptomatic severe AS
Each stage reflects different clinical presentations and severity
What defines ‘severe’ aortic stenosis according to current guidelines?
- Aortic valve area of ≤1.0 cm²
- Peak transaortic jet velocity of ≥4.0 m/s
- Mean aortic gradient of ≥40 mmHg
Definitions may show internal inconsistencies among patients
What is the impact of earlier detection and treatment of aortic stenosis?
Patients are older and more prone to hypertension
This shift affects the treatment approach, focusing on both the stenotic valve and systemic hypertension
What is aortic stenosis (AS)?
Aortic stenosis is a condition characterized by the narrowing of the aortic valve opening, leading to reduced blood flow from the heart to the aorta.
What does the Gorlin formula predict in patients with aortic stenosis?
The Gorlin formula predicts the expected valve area based on the pressure gradient and flow across the valve.
In what percentage of patients is there a discordance between valve area and gradient predictions?
30% of patients.
What should be done for asymptomatic patients with severe AS and LV dysfunction?
They require aortic valve replacement (AVR) even though they are asymptomatic.
What defines LV dysfunction in aortic stenosis?
LV dysfunction may be defined by an ejection fraction (EF) falling below 60%.
What is the prognosis for symptomatic patients with severe AS without AVR?
The prognosis is dire.
What is the average increase in jet velocity for aortic stenosis patients per year?
0.2–0.4 m/s/year.