Download Biocompatibility of Closure Devices

ECMO
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ECMO first developed in 1972 with initially marginal results.
The first neonatal ECMO case – 1976; clinical trials in 1978 halted due
to high efficacy and need for therapy
Primarily used for neonates and pediatrics but recently being used
more often for adult ARDS patients
Permselect.com
Polypropylene hollow fibers similar to dialysis
(hydrophilic)
Bridge to Recovery
Bridge to Transplant
Bridge to VAD
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Thrombosis and emboli formation
Bleeding and dissection of vessels
Seizures due to hemorrhage
Stroke
Pneumothorax
Metabolic complications due to acid-base
balance (CO2 concentrations)
Sensory-neural complications
Developmental delays
http://www.elsonet.org/index.php/resources
/videos/viewvideo/22/elso-centers-ofexcellence/ecmo-centrum-karolinska.html
Cardiac Septal Defects
Shaun White
Tetralogy of Fallot
The heart pumps blood to the pulmonary and systemic circulations
in order to deliver oxygen and nutrients and to remove carbon dioxide
and metabolic waste products from tissues
Fetal circulation
Adult circulation
Key Points:
Flow of blood:
Tissue types:
Lining of CVS:
fetal Vs adult
conductive tissue, contractile tissue, (myocardial
cells) connective tissue
endothelial cells
Atrial Septal Defect
Secundum atrial septal defect
Virtualmedicalcentral.com
This is the most common atrial septal defect, affecting 80 percent of people with this defect.
•It is caused when a part of the atrial septum fails to close completely while the heart is developing.
•This causes an opening to develop between the atria.
•Asymptomatic or symptomatic including shortness of breath, increased susceptibility to pneumonia
and bronchitis, heart murmur, progressive vascular disease in the lung
Ventricular Septal Defect
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10% of congenital cardiac defects
1952-First intra-cardiac surgical
repair of ASD
1976-First transcatheter (PC)
closure
Right side heart dilation,
arrhythmias, emboli are all
indications for repair
Closure of ASDs can be completed
invasively using intra-cardiac
procedures or by catheterization
 Surgeon
 DaVince robot
VSD are usually closed using intracardiac procedures
BEATING-HEART REPAIR OF ATRIAL SEPTAL DEFECTS
Courtesy Nikolay Vasilyev, MD, Children's Hospital Boston
May suggest an increase in closures due to
PC protocols rather than an increase in
disease prevalence
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ASDs and VSDs can be repaired
using a Dacron patch, pericardial
patch or a biomaterial-based
catheter device (see later slide)
Most repairs are completed in
young children in order to
prevent complications such as
arterial damage, pulmonary
disease and congestive heart
failure later on in life
Older patients can have ASD
repair and most of these are
completed successfully and
actually may be unnecessary
since these patients have lived
normal lives with no diseaserelated complications
Starflex VSD device
NMT Medical
Nickel cobalt chromium alloy struts with
Dacron mesh
Pericardial Patch
http://www.youtube.com/watch?v=0NZLpW
rJGgk
http://www.youtube.com/watch?v=WfFLbW
djMEw
Atrioventricular septal defect with tetralogy of Fallot in patient with Down's syndrome
Maria Fernanda Ferrari Balthazar Jacob; Carlos Henrique De Marchi; Ulisses Alexandre Croti; Domingo Marcolino Braile
Pediatric Cardiovascular Surgery Service of São José do Rio Preto - Hospital de Base - Faculdade de Medicina de São José do Rio Preto
Atrial Septal Defect Repair-Catheter Closure
AMPLATZER® Septal Occluder for heart defect repair utilizes the shape memory of
Nitinol, a wire made from an alloy of nickel and titanium. Each Occluder is made of a
Nitinol wire mesh that is shaped into two flat discs and a middle, or "waist" to fit the
defect size, with polyester fabric inserts designed to help close the hole and provide a
foundation for growth of tissue over the occluder after placement. (ADA Medical)
http://www.youtube.com/watch?v=kPfHD2O9mA&feature=related
Americanheart.org
Nitinol
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Nitinol which is a material used for the
supportive strut is an alloy of nickel and
titanium
Nitinol’s mechanical properties include
hardness, impact toughness, fatigue
strength, and machinability
In addition, Nitinol has shape memory
which is a material’s ability return to a
particular shape depending upon
thermal changes
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Strength
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Yield strength is the lowest stress that gives
permanent deformation in a material.
Compressive strength is a limit state of
compressive stress that leads to compressive
failure in the manner of ductile failure or in
the manner of brittle failure
Tensile strength or ultimate tensile strength is
a limit state of tensile stress that leads to
tensile failure in the manner of ductile failure
(yield as the first stage of failure, some
hardening in the second stage and break after
a possible "neck" formation) or in the manner
of brittle failure (sudden breaking in two or
more pieces with a low stress state).
Fatigue strength is a measure of the strength
of a material or a component under cyclic
loading
Impact strength it is the capability of the
material in withstanding by the suddenly
applied loads in terms of energy.
Dacron:
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poly(ethylene terephthalate)
Thermoplastic polymer that becomes liquid when heated
and solid when cooled
Thermoplastics can be molded or extruded into fibers
Generally biocompatible inducing minimal inflammatory
reactions with subsequent fibrotic reactions
Woven
(vascular grafts)
Knitted (ASD patch)
Ventricular Septal Defect Repair-Intracardiac surgical repair
Cardioaccess.com
Wellsley.edu
Ductus Arteriosis in fetal
circulation
Patent Ductus Arteriosis
Americanheart.org
FDA Approved Devices
Americanheart.org
Fibrin
Neoendothelialization
Fibrin
Thrombosis
Cellular organization
Foreign Body Giant Cells
Lymphocyte Infiltration
Implantation of biomaterial
Thrombosis
Endothelium
Neoendothelialization
FBGC
Lymphocytes
Infectious disease, the innate immune response, and fibrosis
J. Clin. Invest. 117:3 doi:10.1172/JCI30595 [Go to this article.]