Prosthetics Flashcards
What are the two main types of prosthetic valves?
Mechanical valves and bio prosthetic valves
Mechanical valves use a tilting disc to open and allow blood flow.
How do mechanical valves function?
They have a disc that tilts to open, allowing blood flow
Mechanical valves are designed for durability and long-term use.
What is a bio prosthetic valve?
A valve replacement from an animal or human
Bio prosthetic valves can be made from biological tissues.
What is a stented porcine valve also known as?
Xenograft pig
This type of valve is derived from pig tissues and is used in bio prosthetic valve replacements.
What is transcatheter aortic valve replacement?
A minimally invasive procedure to replace the aortic valve
It is often used for patients who are at high risk for traditional surgery.
What is an aortic allograft?
A replacement of the ascending aorta and aortic arch
Aortic allografts are used in various surgical procedures, particularly in vascular surgeries.
How is an aortic allograft preserved?
Preserved with antibiotics and cryopreserved at -196°
Cryopreservation helps maintain the viability of the tissue for transplantation.
What effect do mechanical valves have on ultrasound imaging?
Mechanical valves cause major acoustic shadowing
Acoustic shadowing can obscure underlying structures in ultrasound images.
How do mechanical valves appear on echocardiograms?
On Echo, the valve will be very hyper echoic
Hyper echoic indicates a structure that reflects sound waves strongly, appearing bright on the echocardiogram.
What is a distinguishing feature of a bio prosthetic aortic valve?
Has minimal acoustic shadowing
Bio prosthetic valves allow better visualization of leaflets and have three struts.
What is a key characteristic of a mechanical aortic valve?
Significant acoustic shadowing
Mechanical valves do not have struts and are sewn into the anulus, making it difficult to see the disc on echocardiograms.
How many semi-circular discs does the mechanical valve by Saint Jude have?
Two semi-circular discs
These discs open to 85° and have a pivot mechanism.
What is an advantage of a mechanical aortic valve?
Excellent hemodynamic function
Mechanical valves are also less prone to thrombosis.
Fill in the blank: A bio prosthetic aortic valve has _______ visualized leaflets.
3
True or False: Mechanical valves have three struts.
False
Mechanical valves do not have struts; they are sewn into the anulus.
What mechanism does the mechanical valve by Saint Jude utilize?
Pivot mechanism
What is an annuloplasty ring?
A device used to repair the mitral valve during surgery
How can an annuloplasty ring be installed?
Through open heart surgery
What Doppler technique is recommended when using an annuloplasty ring?
CW Doppler
What should be measured when using CW Doppler with an annuloplasty ring?
Mean pressure gradient (MV VTI)
What is a complication of prosthetic valve replacement related to size?
Patient prosthetic valve mismatch(PPM), too small of a valve
This occurs when the prosthetic valve is not adequately sized for the patient’s anatomy.
What does geometric mismatch refer to in prosthetic valve replacement?
Valve positioned in wrong place
This can affect the function of the valve and lead to complications.
What is a para valvular leak?
Valve tears away from the sewing area
This can lead to significant complications and may require surgical intervention.
What is primary failure in the context of prosthetic valve replacement?
Disc or leaflet failure
This refers to the malfunction of the components of the prosthetic valve.
What is pannus formation in relation to prosthetic valves?
New tissue growth onto valve
This can complicate the functioning of the valve and may require additional treatment.
What is a possible infection complication after prosthetic valve replacement?
Endocarditis
This is an infection of the inner lining of the heart, which can be serious.
What is a sign of mechanical aortic valve replacement dehiscence?
Valve is not positioned well within the heart
This is likely due to tearing/splitting of the stitches from the valve and tissue.
What visual motion indicates a mechanical aortic valve replacement dehiscence?
Rocking motion
This occurs when the valve is not properly secured.
What is the normal peak velocity for evaluating aortic stenosis in a prosthetic valve using CW Doppler?
Less than 3m/s
Peak velocity greater than four suggests significant stenosis.
What peak velocity suggests significant stenosis in a prosthetic aortic valve?
Greater than 4m/s
This evaluation is done using CW Doppler.
What is the normal mean gradient for aortic stenosis in prosthetic valves?
Less than 20 mmhg
A mean gradient greater than 35 suggests significant stenosis.
What mean gradient indicates significant stenosis in a prosthetic aortic valve?
Greater than 35
This is assessed using CW Doppler evaluation.
What is the normal peak velocity for determining stenosis in a prosthetic mitral valve?
Less than 1.9 m/s
A peak velocity greater than 2.5 m/s suggests significant stenosis.
What peak velocity indicates significant stenosis in a prosthetic mitral valve?
Greater than 2.5 m/s
This measurement is obtained through CW Doppler evaluation.
What is the normal mean gradient for prosthetic mitral valve stenosis?
Less than five
A gradient greater than 10 suggests significant stenosis.
What mean gradient suggests significant stenosis in a prosthetic mitral valve?
Greater than 10
This is determined using CW Doppler evaluation.
