Medtronic Flashcards
o que é Estenose Aórtica?
condição caracterizada pelo estreitamento da válvula aórtica,
provocado pela impossibilidade dos folhetos valvulares abrirem normalmente
A prevalência da doença valvular diminui com a idade?
não, aumenta, sendo mais comum acima dos 75 anos
Qual é a sobrevida após sintomas de estenose aórtica grave?
50% depois de 2 anos
20% depois de 5 anos
o que é Stenosis?
quando a válvula não abre de forma correta e restringe o fluxo de sangue que passa
o que é regurgitação/insuficiencia?
a válvula não fecha de maneira correta e não consegue prevenir que o sangue retroceda para o coração após o seu bombeamento
Como é que os mecânismos de stenosis são semelhantes à arterosclerose?
- mainly solid calcium deposits with the valve cusps
- similar risk factors to coronary artery disease (CAD)
- high coincidence of CAD and AS in the same individual
- 6th, 7th and 8th decades of life
quais os critérios cardiacos para ser considedado severe Aortic valve stenosis
- valve opening area <1.0 cm^2
- valve opening area index < 0.6
- Mean pressure graient (mmHg) >40
- Maximum flow velocity > 4.0 m/s
- Velocity quotient < 0.25
Classic symptoms od aortic stenosis
- Angina
- syncope
- heart failure
Qual é o gold standard treatment for aortic stenosis patients over 50 years?
- requires cardiopulmonary bypass and sternotomy
- the cardiac naive valve is cut out and a new valve is sewn in place
(SAVR - substituição cirúrgica da válvula aórtica) - treatment options limited in patients with abnormal anatomy, severly calcified aortic arch and a high assessment including prohibitive comorbitidies
what are the 2 types of surgical aortic valve replacements
- Bio prostheses
- Mechanical
o que é a sigla SAVR
surgical aortic valve replacements
(Substituição cirurgica da válvula aórtica - gold-standard por décadas, mas com limitações para pacientes de alto risco)
33% de pessoas com severa AS são recusadas a cirurgia, quais são as razões principais para o tratamento não ser cirurgia?
- a idade
- co-morbidities (coexisting medical conditions)
- high risk of mortality from the procedure
- Inoperable and high risk patients are difficult to treat and had no good option
o que significa TAVR (US) e TAVI (EU)
Transcatheter Aortic Valve Replacement/Implant
(implante transcateter da válvula aórtica - menos invasivo e adequado para pacientes inoperáveis
Todos os paciente podem ser tratados com TAVI?
não, depende da anatomia do paciente
de que depende ser ou não possivel o tratamento com TAVI?
- size of the native aortic valve
- size of the arteries (femoral or sublavia)
- calcification in the pereferal arteries
- Angulations and tortuosity
Com a evolução do design TAV, como está agora?
- nitinol self-expanding frame (sensitive to temperature)
- porcine pericardial tissue
- supra annular valve design
- recapturable and repositionable
Vantagens do uso do Nitinol
- compact design and small delivery systems
- self-anchoring
- controlled retraction for precise delivery and placement
- Maintain valve shape
- resistant to corrosion
- highly biocompatible
- conformable to patient anatomy
- fatigue performance
vantagens do pericardio suíno
- fino, prevenindo a danificação do tecido
- forte, mesmo sobre stress (resistente)
- durabilidade mecânica
- reduz os riscos de danos durante a implantação
o que é e o que pretende a Medtronic Evolut PRO system?
É uma plataforma TAVI avançada, com uma moldura de Nitinol, altamente elaástica, para fixação eficaz. Tem tecido pericárdico suíno para melhor desempenho e durabilidade. Tem um design supra-anular para melhor hemodinâmica
- Advanced sealing
- provide contact at multiple levels in various annulus shapes
- external tissue wrap incrasing surface contact
- controlled, accurate deployment with the ability to recapture
- supra-annular valve function provides unsurpassed hemodynamics
- lowest delivery profile with integrated InLine Sheath
in which procedure is applied the supra annular valve design?
transfemoral procedure
Evolut platforms transfemoral procedure steps and best practices
- Cusp Overlap CT Planning (planeamento com CT)
- Vascular Access (acesso vascular e antiguagolação)
- Crossing the Valve
- Fluoro Load Inspections
- Ballon Aortic Valvuloplaty (balão pré-dilatação (BAV) em casos especificos)
- TAVR Deployment (alinhamento e implantação da válvula com orientação fluoroscópica)
- Post Implant Assessment and Vascular Closure (avaliação pós-implantação e dilatação pós-implnte, se necessário)
qual é a importância do planeamento antes do procedimento com CT?
set the Basal annular plane by placing markers at lowest point in the center of eah cusp in short axis view
(for determination of overlap imaging projections)
what is the cause of errors in perception of TAV depth?
views which do not maintain alignment of cusps
what is the step of vascular access
primarily access vessel determination and performance of a percutaneous arteriotomy according to hospital protocol
(determinar o melhor vaso de acesso, femoral ou outro)
anticoagulation is needed? if yes when should it be administered?
yes, anticoagulation may be administered ate any point before vascular acess, but avoid delaying beyond this point
what is crossing the valve?
- position a reference pigtail catheter in the noncoronary cusp via the contralateral access site
- to reduce contrast use aortic root shot to confirm pigtail placement until after the Evolut system is across the native valve
- once in the ventricle, adcance the angiographic catheter and exchange the straight-tip guidewire for an exchange-length J-tip guidewire
- Extachage the angiographic catheter for 6-Fr pigtail catheter and remove the wire to record the aortic pressure gradient
patient anatomy is important to choose the guidewire?
yes, a more supportive guidewire may be preferred in the presence of tortuous anatomy or horizontal aortic root
why is it important to maintain control of the guidewire?
to ensure stable deployment and prevent injury to the ventricle wall
how can the position of the protetic be ajusted?
by a combination of pushing the wire and pulling the catheter
before performing pre-dilatation or inserting the device into the patient, what should be performed, and why?
fluoroscopic load inspection to confirm proper loading
if a misload is detected, discard the entire system and replace the valve, catheter, loading system, loading tray and saline with new sterile components
why is pre-dilatation ballon Aortic Valvulopasty (BAV) importante?
(recomendado em casos com calcificação severa ou anatomia bicúspide)
- help reduce the potential need for post-dilatation
- may mitigate the occurrence of infolding
- prepares the valve for crossing and implantation of the transcatheter valve
what are the steps of TAVR Deployment?
- insert delivery system with flush port oriented at 3 o’clock
- confirm or realign 3 o’clock flush port orientation prior to crossing arch
- verify hat markers position on outer curve when nearing annulus in LAO view
- visualize TAV commissure location in cusp overlap view
TAV markers are visual references for TAV commissure location during the deployment?
yes
how to assess NCC depth during implantation?
- deploy TAV to just prior to the point of no recapture in the cusp overlap projection
- inject contrast and evaluate frame depth relative to bottom of the NCC
if depth adjustment is needed, the valve may be recaptured and repositioned, true or false?
true
How to confirm TAV performance?
- assess prosthetic regurgitation
- confirm coronary perfusion
- assess TAV frame for infolding (dobra)
how to address infolding?
if patient’s condition allows, recapture, remove, and replace the entire system with new sterile components
what view should be used during redeployment?
Cusp overlap view
what is Recapture Limit?
the valve can be partially or fully recaptured up to 3 times at any point before the “point of no recapture”, allowing for a total of 3 deployment attempts before the valve must be deployed or retrieved
what involves preparing for full release?
- prior to release, mitigate unintended valve movement by relieving system tension
- retract guidewire from ventricle wall
- apply slight forward pressure to the delivery system
- remove pigtail from NCC
- very slowly deploy as outflow region leaves capsule and paddles release
How hemodynamics is evaluated?
- assess valve function using angiography echocardiography and hemodynamics
- if valve function or sealing is impaired due to excessive calcification, bicuspid nature, incomplete expansion, or infolding, a post-implant ballon dilatation (PID) of the bioprosthesis may improve valve function and sealing
How to preform post-implant dilatation?
- advance balloon over guidewire and position within TAV
- initiate pacing to increase valve stability, especially in patients with 34mm valve
(pace at a rate sufficient to achive a desired decrease in systolic pressure) - inflate the balloon under careful fluoroscopic guidance
- deflate the balloon and stop pacing
o que permite a plataforma Medtronic Evolut? (vantagens)
- uma alternativa a pacientes de alto risco (Ex: anatomias complexas)
- menos invasivo
- menor tempo de recuperação
- ajustes precisos, recaptura e reposicionamento garantindo eficácia e segurança, várias vezes antes do posicionamento final.
- o design supra-anular optimiza o fluxo sanguíneo e reduz gradientes de pressão (melhores resultados hemodinâmicos)
