Valve Prosthesis Flashcards
What marked the beginning of modern valve surgery?
The successful operation by Harken to remove foreign bodies from the heart after World War II
This led to further developments in correcting congenital defects and acquired valve disease.
What are the common pathologies that may necessitate intervention on the aortic valve?
Aortic stenosis, aortic insufficiency, and aneurysmal disease of the root and ascending aorta
What is the primary indication for aortic valve surgery in cases of aortic stenosis?
The presence of symptoms such as angina, syncope, or dyspnea on exertion
According to the 2014 AHA/ACC guidelines, what are the indications for aortic valve replacement in symptomatic patients with severe aortic stenosis?
Symptomatic patients with severe AS, symptomatic patients with low flow/low gradient severe AS, and asymptomatic patients with severe AS
List the common diseases leading to aortic regurgitation.
- Calcific degeneration
- Myxomatous degeneration
- Rheumatic disease
- Infective endocarditis
- Bicuspid aortic valves
What are the criteria for determining the severity of aortic stenosis?
Aortic valve area (AVA) and mean pressure gradient
Fill in the blank: Aortic stenosis is the most prevalent valvular heart disease in _______.
adults
What factors should be considered when planning for aortic valve replacement?
- Patient’s age
- Ability to tolerate long-term anticoagulation
- Aortic root size
What are the advantages of mechanical valves?
- Excellent durability
- Greater freedom from valve-related events
- Improved survival compared to biologic prosthesis
- Excellent hemodynamics
What is the primary disadvantage of mechanical valves?
The need for anticoagulation
What are bioprosthetic valves typically made from?
Bovine or porcine tissue
What is a significant advantage of bioprosthetic valves compared to mechanical valves?
Freedom from therapeutic anticoagulation
What are the indications for using homografts in valve replacement?
- Treatment of aortic valve endocarditis affecting the root
- Patients with a small aortic root
- Patients who cannot be anticoagulated
What is the Ross procedure?
Replacement of the diseased aortic valve with a pulmonary autograft and reconstruction of the right ventricular outflow tract with a homograft or xenograft
True or False: The Ross procedure requires long-term anticoagulation.
False
Who are ideal candidates for the Ross procedure?
- Young adults with aortic valve disease
- Women of childbearing age
- High-level athletes
- Patients with a life expectancy greater than 20 years
What is a common risk associated with mechanical valves?
Anticoagulation-related hemorrhage
What are the AHA/ACC guidelines for the severity of aortic regurgitation based on jet width?
- Mild: <25%
- Moderate: 25–64%
- Severe: ≥65%
What are the expected long-term outcomes for patients with mechanical valves?
Less than 2% valve replacement rate over 25 years
What is the risk of thromboembolism with mechanical valves?
0.8% to 2.3% per patient year when anticoagulated
What is structural valve deterioration (SVD) and how does it affect bioprosthetic valves?
SVD leads to higher reoperation rates and falls rapidly after 15 years of follow-up
What is the Ross procedure?
A surgical technique for aortic valve replacement using the patient’s own pulmonary valve
It converts a single valve pathology to a double-valve pathology, increasing reoperation rates.
What are the age considerations for the Ross procedure?
Safe for selected patients up to age 70, but not recommended for those with significantly reduced life expectancy beyond that age
Reports indicate excellent outcomes for both elderly and infants.
List contraindications to the Ross procedure.
- Multivessel coronary artery disease
- Severely depressed left ventricular function
- Multiple valvular pathology
- Disease of the native pulmonary valve
- Connective tissue disease
- Significant aortic root dilation
What is a major criticism of the Ross procedure?
It increases the incidence of reoperations on both the pulmonary autograft and the homograft
Reported incidences of reoperation range from 8 to 15% at 10 years.
What are the long-term outcomes of the Ross procedure compared to mechanical or bioprosthetic valve replacement?
Patients who underwent the Ross procedure showed survival rates approaching that of the general population
This highlights its effectiveness relative to traditional valve replacements.
What is a valve conduit?
A mechanical valve annealed to a Dacron graft or created by suturing a valve to a graft
Considered the gold standard for aortic root replacement.
What is patient prosthesis mismatch (PPM)?
Occurs when a valve prosthesis’s effective orifice area is insufficient for the patient’s body surface area
Can result in elevated gradients across the valve postoperatively.
What is one technique for aortic root enlargement?
Incorporation of a bovine pericardial or Dacron patch to enlarge the diameter
This can help accommodate a larger valve.
What is Transcatheter Aortic Valve Replacement (TAVR)?
An alternative option to open surgical aortic valve replacement
Multiple access approaches include transapical, axillary, and percutaneous femoral.
What did the PARTNER and CoreValve trials examine regarding TAVR?
The utility of TAVR in inoperable and high-risk surgical patients, showing improved one and two-year mortality compared to medical management
TAVR was found to have comparable short-term mortality rates to surgical options.
List the indications for mitral valve repair.
- Severe primary mitral regurgitation (MR) with LVEF >30%
- Severe MR with LVEF <30% (considered)
- Moderate MR undergoing cardiac surgery
- Severe secondary MR during CABG or AVR
- Severe symptomatic secondary MR despite optimal medical management
What is the cornerstone of mitral valve repair?
Annuloplasty, which improves durability of the repair
Various device options exist including rigid and flexible rings.
What are the common techniques for leaflet resection in mitral valve repair?
- Quadrangular resection
- Triangular resection
What is the purpose of artificial chordae in mitral valve repair?
To provide support for the leaflet by connecting it to the papillary muscle
This helps maintain proper leaflet height and coaptation.
What is the Alfieri or edge-to-edge repair technique?
Suturing the anterior and posterior leaflets together to create a double-orifice valve
Useful for bi-leaflet prolapse to maintain leaflet height.
What is the MitraClip?
A percutaneous device used to treat symptomatic chronic mitral regurgitation in high-risk surgical patients
First approved alternative to open surgery in 2013.
What is the MitraClip used for?
To treat patients with symptomatic chronic mitral regurgitation who are at high risk for surgery
When was the MitraClip first implanted?
2003
What significant approval did the MitraClip receive in 2013?
First device approved by the U.S. Food and Drug Administration as an alternative to open mitral valve surgery
What are the indications for MitraClip use?
Severe symptomatic mitral regurgitation (MR > 3+), prohibitive risk for open mitral valve surgery, favorable valve anatomy for repair, reasonable life expectancy
What are the contraindications for MitraClip?
Patients who cannot tolerate anticoagulation or antiplatelet agents, rheumatic mitral valve disease, active endocarditis, thrombus in femoral vein, inferior vena cava or intracardiac thrombus, unfavorable valve anatomy
What technique does the MitraClip procedure utilize?
Edge-to-edge repair as described by Alfieri
What is the outcome of the MitraClip procedure?
Improved coaptation of the mitral leaflets and reduction in the regurgitant jet
What procedural guidance is used during the MitraClip procedure?
Transesophageal echocardiographic (TEE) guidance
What was the rate of major adverse events in the EVEREST II clinical trial for MitraClip compared to surgery?
15% in the MitraClip group and 48% in the surgery group
What is a major disadvantage of the MitraClip procedure?
It may further damage a potentially repairable valve
What is indicated when mitral valve repair is not feasible?
Mitral valve replacement (MVR)
What factors influence the decision for prosthesis type in mitral valve replacement?
Patient age, ability to anticoagulate, patient preference
What is the first-line therapy for patients with mitral stenosis when anatomically feasible?
Percutaneous balloon commissurotomy
What are the criteria for mitral valve surgery in patients with symptomatic severe mitral stenosis?
Patients not candidates for or have failed balloon commissurotomy, recurrent embolic events on anticoagulation, undergoing cardiac surgery for other indications
What is the recommended INR for mechanical valves in the mitral position?
2.5–3.5
What is the general anticoagulation recommendation for patients undergoing mitral valve replacement?
Anticoagulation for the initial 3 months after surgery, including patients with a bioprosthesis
What should be considered for all patients with mitral replacements?
Aspirin
What has increased interest in transcatheter mitral valve replacement (TMVR)?
The increasing adoption and success of TAVR
What structural challenge does TMVR face compared to aortic valve replacement?
The mitral valve and its relationship to left ventricular function and outflow track is more complex
What may provide a solid landing zone for TMVR?
Annuloplasty ring or stent of an implanted bioprosthetic mitral valve
What are primary lesions of the tricuspid valve?
Direct involvement of the tricuspid valve
What are congenital lesions of the tricuspid valve?
Ebstein’s anomaly, tricuspid atresia, and tricuspid stenosis
