CC11: TAVI and Mitra -Clip Flashcards
Causes of MR
-Rheumatic fever
-HCM/DCM
-Mitral valve prolapse
-MI
-Endocarditis
Symptoms of MR
-SOB (pulmonary oedema)
-Arrhythmias/palpitations
-Swollen ankles/feet
Types of MR
Degenerative
-Mitral valve itself is dysfunctional (e.g. prolapse)
Functional MR
-Issues outside of the valve cause leakage
-Most common is heart failure LV dilation causing dilation of the mitral annulus and tethering of leaflets
What does this image show?
-Valve prolapse
-Valve falls behind annular line and flails
How can MI cause MR?
-MI causes papillary muscle necrosis
-Chordae tendon snap
What is pulmonary vein flow reversal?
-Blood flows from LA into pulmonary vein
Intervention options for MR
Gold standard: surgical intervention
-Valve repair
-Valve replacement
However, patient can be at high surgical risk
Mitraclip procedure
-Access: Femoral vein, IVC, RA, puncture IAS, LA
-TOE performed to check LAA for clot, confirm device position and leaflet capture
-Perform gradient checks to confirm not causing stenosis
What does TOE confirm before clip is released?
-Clip position is good for reducing MR
-Clip is not causing mitral stenosis
-Ideally MV mean gradient <5mmHg
Does this echo show significant MR?
-Mean MV gradient <5
-Not significant MR
What does mitraclip leave behind?
-Iatrogenic ASD
What change do you look for in LA pressure after mitraclip?
-Reduction in V wave
-No significant increase in mean pressure
Describe features of Triclip?
-Femoral vein access
-Delivery system differs from mitral system as different angulation
-No need for septal puncture (right side)
-TOE guided
Complications of mitraclip
-Significant residual regurgitation
-Mitral stenosis (mean gradient > 5mmHg)
-Major vascular complication
-Cardiac perforation/tamponade
Causes of mitral stenosis
-Rheumatic fever
-Calcium deposits
-Radiation therapy
-Congenital
Symptoms of mitral stenosis
-SOB
-Fatigue
-Swollen legs/feet
-Palpitations
-Dizziness/fainting
What is the gold standard treatment for mitral stenosis?
Surgical valve replacement
Other methods of treating mitral valve
-Mitral valve balloon valvuloplasty
-Mitral valve replacement (TMVR)
What is the lampoon procedure?
-Cutting the mitral valve prior to TMVR
-This prevents LVOT obstruction
How to perform trancatheter tricuspid valve replacement (TTVR)?
-TOE and angio guided to confirm position
-TOE and RV gram to check for significant leak
-Usually for valve in valve procedures
Who is pulmonary valve replacement done on?
-Congenital patients
How does tricuspid valve replacement affect RV function?
-RV contraction is mainly longitudinal (up and down)
-Tricuspid valve reduces longitudinal function
-Causes poor RV function
What are the causes of aortic stenosis?
-Calcium build up on valve
-Congenital
-Rheumatic fever
Symptoms of aortic stenosis
-Chest pain
-Dizziness
-SOB
-Fatigue
-Palpitations
Risk factors for aortic stenosis
-Older age
-Congenital
-Diabetes
-High cholesterol
-High blood pressure
Diagnosis of aortic stenosis
-Heart murmur
-Cardiac cath
-Imaging: Echo, MRI, CT
Treatment for aortic stenosis
-Surgical aortic valve replacement
-Balloon valvuloplasty
-TAVI
Factors to consider when choosing between surgical AVR and TAVI
-Patient’s age
-Patient’s choice
-Estimated surgical risk/co-morbidities
-Clinical characteristics
-Anatomical and technical aspects
What is the gold standard treatment for aortic stenosis?
-Surgical aortic valve replacement
How is surgical aortic valve replacement carried out?
-Patient on heart/lung bypass machine
-Medical sternotomy
-Stenotic valve removed and replaced with new valve
Why would surgical aortic valve replacement be chosen over TAVI?
-Poor TAVI access
-Aortic dimensions unsuitable
-Valve morphology unfavourable
-Active or suspected endocarditis
-Other surgical intervention required
What are the types of surgical valve?
Mechanical
-Very durable
-Needs lifelong anticoagulation due to increased risk of blood clots
Tissue valve
-Can be human or porcine
-Less durable
-Does not require anticoagulation
Why is balloon aortic vavuloplasty not used anymore?
-Prior to TAVI, BAV was the only alternative to surgical AVR
-However, it poses a significant risk of AR
-Now used as part of TAVI, pre or post valve
Why is pacing used in TAVI?
-Fast pacing required to lower blood pressure
-This prevents valve being displaced by the LV/aortic pressure
-Pacing normally >180bpm
Benefits of TAVI
-Less invasive
-Shorter procedure time
-Less/no intensive care time
-Shortened recovery time/hospital stay
-More rapid improvement in QoL
What is access for TAVI?
-Radial access for pigtail catheter for aortagram
-Valve requires a large access
=> Transfemoral
=> Subclavian
=>Transcaval
What is transcaval approach?
-Femoral vein into femoral artery
Pre TAVI procedures
Echocardiogram
-Assess aortic valve, morphology, gradients, valve area, regurgitation
-Assess for other valvular disease
-Assess chamber size and function
CT scan
-Assess aortic valve diameter and area
-Valve calcium score
-Measure coronary height
-Access entire course of aorta and femorals for access evaluation
How did TAVI valves develop
-New valves have skirts to prevent paravalvular leak
What should you do if you’re trying to pace at 180 but not achieving?
-Check Safari wire position
-Refractory time with blocked paced beats
-Consider starting slow and ramping up
What should you do if you’re pacing at 180bpm but not enough pressure drop?
-Pace faster
-However, more risk of triggering VT/VF
Why do you do aortagram after valve is implanted?
-Check for paravalvular leak
-Check coronaries are not blocked
What are self expanding valves?
Abbott Navitor
-No need for rapid pacing
-Gradual deployment - valve can be retracted
-Large open cell geometry - minimises obstruction to coronary ostium
-Reduces paravalvular leak
What is a complication of TAVI?
-Paravalvular leak
Causes of paravalvular leak?
-Native anatomy - calcification
-Under-expanded valve - could balloon valve
-Undersized valve
-Valve malposition
How to identify paravalvular leak?
-Angiography
-Intra-procedural TTE
-Haemodynamics (AR)
TAVI vs surgical AVR risk
-No significant difference in death, stroke, MI
TAVI higher risk of:
-Major vascular complications
-Paravalvular leaks
-Need for permanent pacemaker
Surgical AVR higher risk of:
-Major bleeding
-Tamponade
-Increased risk of post-operative AF
Why is there a high pacing risk with aortic valve replacement?
-Aortic valve is near AV node/bundle branches
What is most common conduction abnormality in TAVI?
-LBBB
-AV block
-Self expanding valves more likely to cause conduction disturbances due to exerting higher pressures
Why would you not use temporary pacing wire for all patients?
-Creates hole that increases risk of cardiac tamponade and vascular complications
-Use Safari guidewire instead unless patient is high risk (RBBB and AV block)
-Patient’s pacemaker can be used
Downsides of Safari pacing
-Wire is supporting the whole TAVI system, not stable, unreliable threshold
-Pace at max output of temporary pacing box
-If pacing dependent post-procedure, can’t remove TAVI delivery system because pacing clip is on wire
What is the Jena valve for AR?
-Can be used on a non-calcific aortic valve
-Therefore, can be used for AR
-Clips to native leaflet to secure position
Why do echo pre and post TAVI?
-Check for effusion
-Check for AR post TAVI
-Anything unexpected (e.g. LV function, RV size, MR)
