Transcatheter Aortic Valve Replacement Flashcards
What is calcific aortic stenosis (AS)?
The most frequently encountered valvular heart disease in the Western world, characterized by a slow, progressive asymptomatic phase followed by poor prognosis once symptoms develop.
The 5-year survival rate is only 15–50% when managed without valve replacement.
How does the prevalence of aortic stenosis change with age?
It increases with age, showing a prevalence of 0.02% in patients aged 18–44 years to 2.8% in those over 75 years.
The Euro Heart Survey indicated aortic stenosis was present in 43.1% of patients with valvular heart disease.
What was the only effective treatment option for aortic stenosis until recently?
Surgical aortic valve replacement (SAVR).
SAVR has been shown to prolong life even in patients over 80 years of age.
What percentage of patients over 75 years with severe AS are not candidates for SAVR?
33%.
This is due to a high burden of comorbidities.
What treatment option has emerged for aortic stenosis patients who are at high or intermediate surgical risk?
Transcatheter aortic valve replacement (TAVR).
Who performed the first-in-man TAVR and when?
Dr. Alan Cribier in 2002.
What are the two major valve platforms approved for TAVR in the USA?
Edwards SAPIEN Balloon-Expandable Valve (BEV) and Medtronic CoreValve Self-Expanding Valve (SEV).
What are the current approved indications for TAVR?
Patients with severe symptomatic aortic stenosis with a life expectancy of more than 1 year who are either inoperable or have high or intermediate surgical risk.
What are absolute contraindications for TAVR?
Absence of a heart team, estimated life expectancy less than 1 year, severe primary associated disease of other valve, inadequate annulus size, thrombus in the left ventricle, active endocarditis, elevated risk of coronary ostium obstruction, and inadequate vascular access.
These contraindications must be assessed by a heart team.
What is a relative contraindication for TAVR?
Bicuspid or noncalcified valves, untreated coronary artery disease, hemodynamic instability, LVEF less than 20%.
Severe pulmonary disease is a relative contraindication for the transapical approach.
What is the role of risk stratification in TAVR evaluation?
It helps determine the appropriateness of TAVR use based on the level of risk.
What scoring systems are used for risk stratification in TAVR?
Society of Thoracic Surgeons (STS) projected risk of mortality (PROM) score and Logistic European Score for Cardiac Operative Risk Evaluation (LES Euroscore).
What is the STS mortality score cutoff for TAVR use?
> 4%.
What newer scoring systems have been developed for TAVR risk assessment?
EuroSCORE II, ACEF score, TVT TAVR In Hospital Mortality Score, Aortenklappenregister score.
What is essential for the success of a TAVR program?
Appropriate patient screening and evaluation by a heart team.
What imaging modalities are typically used in the workup for TAVR?
Transthoracic echocardiography (TTE), multi-slice detector computed tomography (MDCT), angiography, transesophageal echocardiography (TEE), and MRI.
What is assessed during pre-procedural echocardiographic imaging for TAVR?
Aortic valve morphology, calcification, hemodynamics, left ventricular function, right heart function, and pulmonary hypertension.
What is the focus of imaging in TAVR evaluation?
Evaluation of ilio-femoral access for size, tortuosity, and calcification for transfemoral approach.
What is the significance of aortic annulus size in TAVR?
It determines the appropriate size of the prosthesis.
What is the role of angiography in TAVR?
Used for estimating pulmonary artery pressures
Angiography is utilized for assessing hemodynamics during the procedure.
What imaging techniques are used to assess aortic annulus size?
3D TEE and MDCT
These imaging modalities are crucial for determining the appropriate size of the prosthesis.
Name two comorbidities that increase surgical risk in TAVR patients.
- Radiation heart disease
- Heavily calcified ascending aorta (porcelain aorta)
What is a relative contraindication for TAVR?
Severe pulmonary hypertension
Other contraindications include severe LV dysfunction and certain anatomical considerations.
How does chronic kidney disease (CKD) affect TAVR outcomes?
Associated with worse outcomes and higher risk of acute kidney injury post-TAVR
Patients with CKD have been excluded from many TAVR trials, making long-term benefits unclear.
What preprocedural creatinine level is associated with a sixfold increased risk of mortality?
> 1.58 mg/dL
This level of creatinine serves as a critical marker in risk assessment.
What percentage of patients with severe AS have significant coronary artery disease?
40–75%
This prevalence indicates a need for careful evaluation of coronary status in TAVR patients.
What is the impact of concomitant coronary artery disease on TAVR outcomes?
Increased 2-year mortality by twofold
The relationship between CAD and TAVR outcomes requires further investigation.
What is the significance of mitral valve disease in TAVR patients?
Indicates more extensive cardiovascular disease limiting TAVR effectiveness
Up to one-third of patients evaluated for TAVR have severe mitral valve disease.
How does systolic dysfunction affect TAVR outcomes?
Higher adverse events but similar overall mortality
Patients with lower LVEF still show improvement post-TAVR.
What is the association of chronic lung disease with TAVR outcomes?
Increased 1-year mortality in patients with severe chronic lung disease
These patients may experience improved outcomes compared to medical management.
Define frailty in the context of TAVR.
A state of decreased physiological reserve predisposing to poor outcomes
It is assessed through various physical and cognitive tests.
What gait speed indicates an increased risk of long-term mortality in TAVR patients?
<0.5 m/s
This threshold has been shown to correlate with higher mortality rates.
What does the Essential Frailty Toolset assess?
Lower extremity weakness, cognitive impairment, anemia, and hypoalbuminemia
This tool is predictive of mortality and disability in TAVR patients.
What procedural step is routinely performed before TAVR?
Preimplantation balloon aortic valvuloplasty
This step is done under rapid right-ventricular pacing to prepare the native annulus.
What is the main benefit of TAVR for patients with low-gradient severe AS?
Improvement in functional capacity and larger improvement in LVEF compared to matched SAVR patients
Mortality is higher in these patients, but TAVR offers better outcomes than medical therapy.
What are the common domains to assess frailty?
Weakness, slowness, exhaustion, low activity, weight loss, and poor nutrition
These factors help determine a patient’s frailty status.
What is routinely performed under rapid right-ventricular pacing during preimplantation balloon aortic valvuloplasty?
An undersized balloon (1–2 mm smaller than the measured aortic annulus diameter)
This is done for preparing the native annulus in all cases except pure aortic regurgitation or degenerated aortic bioprosthesis.
What does a frailty index score of ≥3 indicate?
Frailty
The Multidimensional Geriatric Assessment (MGA) includes various tests such as the mini-mental state examination and timed get up and go test.
What are common clinical characteristics associated with patients unlikely to benefit from TAVR?
- High STS score (STS > 15)
- Extreme frailty with dependent social status
- Severe pulmonary and liver disease
- Severe dementia
- Chronic kidney disease (dialysis dependent)
- Hemodynamic instability (especially requiring pressors)
Further research is needed to identify these patients better during the screening phase.
What approach was first used for TAVR by Dr. Cribier?
Antegrade trans-septal approach
Most TAVRs currently use the transfemoral (TF) approach.
What is included in access screening for TAVR?
- Assessment of iliofemoral size
- Tortuosity
- Calcification using MDCT or angiography
This establishes the feasibility of the TF approach.
What are alternative access sites for TAVR in patients with unsuitable ilio-femoral anatomy?
- Transapical (TA)
- Transaortic (TAo)
- Trans-axillary
- Transcarotid
- Trans-caval access
The TA route is the most common alternative access route for the Edwards valve.
What is the main advantage of the TA approach in TAVR?
Avoiding tortuous and diseased ilio-femoral vasculature
It also allows for a prosthesis co-axial with the aortic annulus.
What are the disadvantages of the TA approach in TAVR?
- Need for thoracotomy
- Myocardial injury
- Left ventricular pseudo-aneurysm from apical perforation
- Bleeding complications from the surgical site
These risks need to be considered when choosing the access approach.
What is the recommended valve sizing process for TAVR?
Using protocols specific for the valve type employed and optimizing implantation with concurrent TEE and fluoroscopy
A three-dimensional understanding of the aorta, LVOT, and aorto-mitral continuity is essential.
What is the nominal area for a 26 mm balloon-expandable valve?
531 mm2
This is part of the sizing algorithm for second- and third-generation balloon-expandable valves.
What size delivery catheters are required for the Edwards Sapien valve?
- 22 F for 23 mm
- 24 F for 26 mm
The original Edwards Sapien valve was the first balloon-expandable valve implanted by Cribier et al.
What is the main feature of the Sapien 3 THV?
Incorporates an additional outer skirt to reduce the risk of paravalvular leak
It is also mounted in a cobalt chromium stent.
What was the primary outcome of the PARTNER I trial for TAVR?
- All-cause mortality
- Cardiovascular mortality
- Repeat hospitalization
- Composite endpoint of death or repeat hospitalization
Results showed significantly lower rates in patients randomized to TAVR.
