Biomaterials in Medical Devices - Homepage | …didattica.uniroma2.it/assets/uploads/corsi/144507/Medtronic.pdf · Biomaterials in Medical Devices Eunsung Park, ... • Disadvantages

Biomaterials in Medical Devices

Eunsung Park, Ph.D.Medtronic Strategy and Innovation

Medtronic, [email protected]

Contents of Lectures Overview of Biomaterials

Biomaterials and Biocompatibility Overview of Medical Devices

Focus on implantable, therapeutic devices Heart Valves

Mechanical valves and Bioprosthesis Stents

Stent delivery system Bare metal stents and Drug eluting stents

Pacemakers and ICDs Components MRI compatibility issues

Surface Properties Surface energy Surface treatments and coatings

1/40

Introduction

2/40

Materials Science and Engineering

Transparent Plane??!@!

3/40

What are biomaterials?

Materials used to make devices to replace a part of a function of the body in a safe, reliable, economic, and physiologically acceptable manner. (Hench and Erthridge, 1982)

A nonviable material used in a medical device intended to interact with biological systems. (Williams 1987)

Biomaterials are used in medical devices in direct contact with biological systems.Biomaterials are defined by their application, NOT chemical make-up.

4/40

Study of Biomaterials S&E

Interdisciplinary, integrated, sophisticated materials science + biology + physiology +

biochemistry + clinical science +

Wide range of materials metals, ceramics, polymers, composites,

biological materials

in a biological environment

5/40

MIT OCW

6/40

Stainless Steel Ti and alloys Co alloys NiTi Pt-Ir, Ta Au

Metallic Biomaterials

7/40

Advantages Properties and fabrication well

known High mechanical strength Stiff and strong Fatigue resistance, wear

resistance Joining technologies known

Disadvantages Corrosion Metal ions may be toxic

Metallic Biomaterials

8/40

Pyrolytic carbon, Diamond-like carbon Alumina, Zirconia Hydroxyapatite / Calcium phosphates Bioglasses A/W glass-ceramic

BioCeramics

9/40

Advantages Similar in physical properties to bone Readily sterilized High compressive strength when dense Low to high bioreactivity

Disadvantages Difficult to fabricate Low strength in tension, torsion, bending,

or impact

BioCeramics

10/40

Silicone Polyurethane; Polyethylene: PE Poly(methyl methacrylate): PMMA Poly(ethylene terephthalate): PET (Dacron) Poly(tetrafluoroethylene): PTFE (Teflon) Hydrogels Bioresorbable (biodegradable) polymers

PGA, PLA, PGLA, Polycaprolactone

Polymer Biomaterials

11/40

Advantages Easy fabrication Wide range of compositions and properties Many ways to immobilize biomolecules/

cells

Disadvantages Contain leachable compounds

Additives (stabilizers, plasticizers, etc.)

Surface contamination Chemical/ biochemical degradation

Mobility

Difficult to sterilize

Polymer Biomaterials

12/40

Applications of Biomaterials

Orthopedic artificial hips, knees, shoulders, wrists; intervertebral discs; fracture

fixation; bone grafts

Cardiovascular heart valves, pacemakers, catheters, grafts, stents, PTCA balloons

Dental enamels, fillings, prosthetics, orthodontics

Soft tissue wound healing, reconstructive and augmentation, intra-ocular lens

Surgical staples, sutures, scalpels, surgical tools

13/40

Criteria for Biomaterials as Implants

Have required physical/chemical properties and maintain these properties over desired time period.

Do not induce undesirable biologic responses.

Should be manufactured and sterilized easily and reproducibly.

14/40

Physical Properties Mechanical properties, tensile, compressive, fatigue Transport properties Degradation rate, degradation products Surface properties, chemistry, morphology, roughness

Biological interactions Materials-Body interactions Toxicity, Decomposition

Formability Design Issues Liability

Issues of Biomaterials in Medical Devices

15/40

Understanding and controlling performance Physical, Chemical, Biological

Relevant material performance under biological conditions 37 C, aqueous, saline, extracellular matrix (ECM)

Material properties as a function of time Initial negative biological response - toxicity

Long term biological response rejection

Biology is a science of surfaces and interfaces and it is never at equilibrium.

Contd

16/40

Value LocationpH 6.8 Intracellular 7.0 Interstitial 7.15-7.35 BloodpO2 2-40 Interstitial (mm Hg) 40 Venous 100 ArterialTemperature 37 Normal Core 28 Normal SkinMechanical Stress 4x107 N m-2 Muscle (peak stress) 4x108 N m-2 Tendon (peak stress)Stress Cycles (per year) 3x105 Peristalsis 5x106 - 4x107 Heart muscle contraction

Length of implant: Day, Month, Years

Test Conditions:

17/40

Biocompatibility

Old Definition Non-irritant, Non-toxic, Non-carcinogenic, Non-

allergenic, etc.

New Definition The ability of a material to perform with an

appropriate host response in a specific application. D. Williams

18/40

Biocompatibility

Is a collection of processes involving interactions between the materials and the tissue.

Refers to the ability of the material to perform a function.

Refers to the appropriate host responses. Does not stipulate that there should be no responses.

Is NOT an intrinsic material property.

19/40

Assessing Biocompatibility

Question: Will this material stimulate the appropriate biological response for the intended use?

In vitro tests In vivo/Usage tests

Clinical Trials

20/40

In Vitro Analysis of Cell/Biomaterial Interactions

Nature of cell/biomaterial interactions

Fundamental phenotypic/functional differences

Soft/hard tissue cells

Cell number, growth rate, metabolic rate, cell function, protein expression

Simple, repeatable, inexpensive, rapid

21/40

In Vivo Tests

Relevant mammalian model

Comprehensive biological response

Ethical concerns

Expensive & time-consuming

22/40

Clinical Trials

Most relevant test

Safety and efficacy test

All other tests measured against this

Expensive, logistically complicated

Difficult to interpret results

23/40

Biological Responses to Biomaterials

In Tissue Inflammation, Fibrous Tissue Formation, Immune

Response, Infection, Necrosis

In Blood Thrombosis, Lipid or Mineral Deposition, Infection

24/40

Types of Implant-Tissue Response

If the material is Response

toxic the surrounding tissue dies

nontoxic and nearly inert a fibrous tissue forms

nontoxic and bioactive an interfacial bond forms

nontoxic and dissolves the surrounding tissue replaces it

25/40

Why do Medical Devices Fail?

The types of materials failure in the failure of biomedical devices Mechanical Physico-chemical Chemical (biochemical, electrochemical) Device Design

Device failure can be catastrophic to the patient and, at the least, costly and risky We often dont have good long term descriptive tests for

medical devices in-vivo High risk nature precludes new device adoption

26/40

Mechanisms of Biomaterial Breakdown

Mechanism Breakdown

Mechanical Creep, Wear, Stress cracking, Fracture

Physico-chemical Adsorption of biomolecules (fouling),

Absorption of water (softening), Desorption of low MWs (weakening), Dissolution

Biochemical Hydrolysis, Oxidation, Reduction, Mineral deposition

Electrochemical Corrosion

27/40

Mechanical Failure

Mechanisms: Creep: Long term deformation under load Wear/Abrasion: Surface failure during working Stress cracking: Stress relief in local environment Fatigue: Breaking under cycling load Tensile/Torsion/Compression failure

Issues: Material choice Testing Failure analysis: fractography

28/40

Fractography: ductile fracture

29/40

Fractography: brittle fracture

Mirror

Mist

Hackle

http://www.doitpoms.ac.uk/tlplib/fracture/images/glass2.gif

30/40

Physico-chemical / Chemical Failure

Protein/cell adsorption on the surface - fouling Property decay through water interactions

softening, crazing Leaching of plasticizer, filler, etc. in bio environment Dissolution of component/device Materials degradation of device - hydrolysis of

esters or amides Corrosion - oxidation or reduction Calcification - growing unwanted bone or Ca

deposits Catastrophic fibrous encapsulation

31/40

Material Selection Factors Mechanical

tensile, compression, dynamic, fracture, stress, strain, stiffness, creep, fatigue

Electricalresistance, contact, power supply, earthing, insulation, electromechanical

compatibility Thermal

shrinkage, expansion, stability, insulation Chemical

(bio)stability, degradation, corroision, interaction/reaction Environmental

product life span, shelf life, humidity, manufacturing waste, recyclability Surface

finish, wear, friction, tactility (feel) Aesthetic

Cosmetic appearance, colors, visual clarity Economic

Material cost, process introduction

32/40

Medical Device Sterilization

To kill the microorganisms

Sterilization processes E-beam

Gamma radiation

Ethylene oxide (EtO)

33/40


E-beam Accelerated high energy electrons (10MeV)

Damages DNAs

E-beam causes crosslinking and chain scissoring of polymers (Teflon, PP, etc.)

34/40


Gamma radiation Radioisotope (Co60) generated

gamma rays

Damages DNAs and cellular structures

Quick turnaround; easy penetration

Not for some polymers: acetyls, Teflon, PP

35/40


Ethylene oxide (EtO) Ethylene oxide gas, temperature, humidity

Disrupts DNAs

For nearly all materials

Takes long time: pre-condition (T, humidity), sterilization, aeration

Aeration is particularly a problem for polymers (absorbed must be desorbed)

36/40

Effects of Sterilization Radiation process: e-beam and

gamma Radiation affects materials with

low binding energy. Energy of radiation breaks the

molecular bonds.

For some polymers (acetyls, Teflon, PP), crosslinking or scissoring occurs.

It also affects batteries and electronic components.

Gamma radiation changes the color grade of ceramics.

ZrO2 hip balls turn dark after sterilization.

37/40

Effects of Sterilization

Ethylene oxide (EtO) Aeration is particularly a problem for polymers and porous

materials.

Polymers absorb EtO easily. Sterilization is effective, however, all absorbed EtO must be removed (aeration).

38/40

Bio-Materials Technologypast, present, future

BIOmaterials

time

bioMATERIALS

BIOMATERIALS

39/40

Evolution of Biomaterials

Structural

Functional Tissue Engineering Constructs

Soft Tissue Replacements

40/40

Progression of Biomaterials Technologies: Compatibility

1960s

Biostability

DurabilityTolerance by body

1980s

Biocompatibility

Blood and tissue compatibility

Bio-Interactivity

Living implants Modification of cells

2000

1/26

Medical Devices

2/26

What Is a Medical Device?

What is not?

3/26

Definition of a Medical Device(by US FDA)

An instrument, apparatus, or implant intended for diagnosis, treatment, or prevention of disease affect the structure or function of the body without chemical action or metabolism

Range from simple tongue depressors to complex programmable pacemakers with micro-chip technology and laser surgical devices

4/26

Classification of Medical Devices(by US FDA)

Classification depends on three factors Intended use - What disease, symptom, or

condition is the device intended to treat? How will the device be used?

Indications for use - What kinds of patients should this be used on? Can be based on age, disease state, medical history, allergies, etc.

Level of risk - Is the device life-saving? Is the device life-sustaining? Is there an unreasonable risk of illness or injury associated with use of the device?

5/26


Class I: General Controls Present minimal potential for harm to the user

Devices whose safety & effectiveness are well-established

Registration with the FDA, GMP, proper labeling, notification of FDA before marketing

About 40% of all devices are Class I

Tongue depressor, bandages, exam gloves

6/26


Class II: General controls with specific controls Subject to special controls of special labeling,

mandatory performance standards, postmarket surveillance, preclinical testing

About half of all devices are Class II

Contact lenses, x-ray machines, powered wheelchairs, infusion pumps, surgical needles, suture materials, acupuncture needles

7/26


Class III: General controls and Premarket Approval Premarket approval, scientific reviews to ensure

the devices safety and effectiveness

Life-supporting or life-sustaining devices

Less than 10% of all devices are Class III

Heart valves, pacemakers, breast implants, stents

8/26

Getting a Device to Market

For a Me Too device 510(k) Notification

Manufacturer must show substantial equivalence to already marketed device.

For a new device Pre-market Approval (PMA)

Manufacturer must show safety and effectiveness of new device.

9/26

Substantial Equivalence

A device is found substantially equivalent (SE) if, in comparison to a legally marketed device, it: Has the same intended use, and Has the same technological characteristics as the

pre-existing (predicate) device; or Does not raise new questions of safety and

effectiveness, or demonstrates equal safety and effectiveness

10/26

Premarket Approval

For a New Device (in Class III)

Premarket Approval (PMA) requires Valid Scientific Evidence showing safety and

effectiveness

Laboratory and Animal Study

Clinical Study

11/26

Classes of Medical Devices

Diagnostic Devices Monitoring Devices Therapeutic Devices

---------------------------- External Devices

Implanted Devices----------------------------

Devices for Acute Care (short-term use) Devices for Chronic Care (long-term use)

12/26

Diagnostic Devices

Determine the cause of disease or injury Examples

Imaging (X-ray, CT, MRI) DNA-base diagnostics; POC devices Cardiac marker-base diagnostics

13/26

Monitoring Devices

Determine the progress of therapy and the state of the patient in response to therapy

Examples Blood pressure ECG Blood oxygen monitor

14/26

Therapeutic Devices

Change structure and function of the biological system to alter the course of disease

Examples Pacemakers Stents Spinal fixation devices

15/26

Classes of Medical Devices Diagnostic Devices Monitoring Devices Therapeutic Devices

---------------------------- External Devices

Implanted Devices----------------------------

Devices for Acute Care (short-term use) Devices for Chronic Care (long-term use)

Implantable Therapeutic Medical Devices for Chronic Diseases

Most Advanced Technologies=

16/26

Cardiac Rhythm DisordersSudden cardiac arrest Implantable cardioverter defibrillators (ICDs)

Heart failure Cardiac resynchronization systems (CRT)

Arrhythmias Pacemakers

Unexplained syncope Implantable diagnostic recorders

Disease management Internet-based information technology system

For full safety information, visit medtronic.com

17/26

Spinal Conditions

Spinal deformities Fusion systems

Herniated discs Minimal Access Spinal Technologies (MAST), artificial discs

Acute tibial fractures Bone morphogenetic proteins


Fixation Systems

18/26

Cardiovascular DiseasesVascular disease Catheters, angioplasty balloons, implantable

stents, open-heart surgery perfusion and stabilization systems

Aortic disease Implantable stent grafts

Heart valve disease Artificial valves


19/26

Neurological DisordersMovement disorders Implantable deep brain stimulation systems

Chronic pain Implantable neurostimulation systems, drug-infusion systems

Hydrocephalus Implantable shunts (cerebrospinal fluid)


20/26

Urological and Digestive Disorders

Acid reflux Diagnostic tools

Gastroparesis Implantable gastric stimulation systems

Overactive bladder/urinary retention Implantable sacral stimulation systems

Enlarged prostate Radio frequency ablation systems


21/26

Diabetes

Glucose monitoring Real-time continuous glucose monitoring systems

Insulin delivery External and implantable insulin pumps

Disease management Internet-based information technology system


22/26

Bio-Materials Technologypast, present, future

BIOmaterials

time

bioMATERIALS

BIOMATERIALS

23/26

Drugs

Biologics

Devices

Combin

ation

Combination

Com

bin a

ti on

Drugs

Biologics

Devices

Combination Products

24/26

Antibiotic bone cement and orthopedic implants

Steroid eluting pacemaker

Lumbar fusion device with growth factor

Drug eluting stents

Combination Products

25/26

Recently ApprovedCombination Products

Transdermal patch for treatment of Parkinsons disease

Absorbable collagen sponge with genetically engineered human protein

Transdermal patch for ADHD

Transdermal patch for Depression

Inhaled insulin for diabetes

Dental bone grafting material with growth factor

Surgical mesh with antibiotic coating

Dermal iontophoresis system

..Source: Office of Combination Products, FDA, www.fda.gov/oc/combination/approvals.html, as of May, 2007

http://www.fda.gov/oc/combination/approvals.html

26/26

Miniaturization and longevity

Improved sensors and diagnostics

Enhanced biomaterials

Better disease prevention

Better technologies

Traditional Medical

Technology

Biotechnology

Nanotechnology

Information technology

+

Innovative Medical Technology

1/30

Heart Valves

2/30

Prosthetic Heart Valve

A prosthetic (artificial) heart valve is a replacement for a diseased or dysfunctional heart valve.

3/30

Heartand

HeartValves

Right Atrium

Right Ventricle

Left Ventricle

Left Atrium

Pulmonary Vein Aorta

4/30

4 Heart Valves

Body

Lung

LungBody

Texas Heart Institute

Tricuspid

Mitral

Pulmonary

Aortic

Superior vena cava

Pulmonary artery

Blood Flow: Body->RA->RV->Lung->LA->LV->Body

Heart Pump: Atrial contraction (RA/LA->RV/LV)

Ventricular contraction (RV/LV->Lung/Body)

5/30

Heart Valves

7/30

Mitral Valve

8/30

When is it used?

Two conditions that may require a heart valve replacement are Stenosis (smaller opening)

Leaflets thicken or stiffen

Regurgitation (incompetence) Valve doesnt close properly and blood leaks backward

9/30

Type of Prosthetic Heart Valves

Mechanical heart valves

Biological heart valves

Medtronic Hancock II Medtronic Freestyle Medtronic Mosaic

10/30

Mechanical Heart Valves Caged ball valve

Occluder in restraining cage 1960s Very durable, but suboptimal

hemodynamics

Tilting disc valve Single leaflet on a central strut Good hemodynamics

Bileaflet valve Two leaflets rotate on pivots

St. Jude medical

Medtronic

Edwards

11/30

Mechanical Heart Valves Advantages

The main advantage of mechanical valves is high durability. They usually last a lifetime.

Disadvantages Mechanical heart valves can increase the risk of blood

clots. Because of this, patients must take anticoagulant (blood thinners) for the rest of their lives.

Even though blood thinners are relatively safe, they do increase the risk of bleeding in the body.

13/30

Biological Heart Valves

Stented Mostly made from porcine aortic valves

or bovine pericardium Preserved in glutaraldehyde (reduces

calcification) Sewing ring provides structural stability Some hemodynamic issues

Stentless Primarily made from aortic valves Implanted on native valvular annulus w/o

a sewing cuff Provides native anatomical and

hemodynamic profiles Medtronic Freestyle

Medtronic Mosaic

14/30

Biological Heart Valves Advantages

Excellent hemodynamics

Less prone to thromboembolism. Anticoagulant therapy is generally not necessary.

Disadvantages Biological heart valves may wear out over time. They may

need to be replaced every 10 to 15 years.

Calcification can be a problem. (More with young patients.)

15/30

Materials in Mechanical Heart Valves

Valve housing CP Ti (grade 4), PyC coated cage,

Co-Cr alloys

Sewing rings/cuffs Polyester (Dacron), PTFE (Teflon)

Occluder (Leaflet) Pyrolytic carbon coated graphite

(W doped graphite)

Most commonly used materials

16/30

CP Ti All -Ti (HCP) ~99% Ti with O

Grade 1 ~ 4 according to O content (0.18 ~ 0.4 %).

Oxygen has a great influence on yield/fatigue strength and corrosion resistance, with acceptable ductility.

Properties Grade 1 Grade 2 Grade 3 Grade 4

Oxygen (w/o) 0.18 0.25 0.35 0.40

Tensile strength (MPa) 240 345 450 550

Yield strength (MPa) 170 275 380 485

Elongation (%) 24 20 18 15

Area reduction (%) 30 30 30 25

Oxygen Concentration and Mechanical Properties of CP Ti

17/30

Yield Strength to Density Ratio

18/30

Co-Cr Alloys 2 major areas of use for the Co-Cr alloys are orthopedic

(prosthetic replacements, fixation devices) and cardiovascular (heart valve).

Good corrosion resistance and mechanical properties Co-Cr-Mo (F75, F799)

Vitallium (Howmedica), Haynes-Stellite (Cabot), Zimaloy (Zimmer)

Good corrosion resistance in chloride environment Orthopedic, Dental

Co-Ni-Cr-Mo (F562) MP35N (SPS Technologies) High strength/corrosion resistance Good fatigue strength Cardiovascular (stents)

19/30

Relative Properties: Metals

20/30Buddy Ratner, Introduction to Biomaterials

21/30

Pyrolytic Carbon Similar to graphite, but with some covalent bonding

between its graphene sheets: disordered wrinkles and distortions within layers improved durability

Belongs to turbostratic carbons Produced by heating a hydrocarbon nearly to its

decomposition temperature, and permitting the graphite to crystallize (pyrolysis).

disordered

22/30

Is man-made.

Is a coating. Deposited through the thermal decomposition

of hydrocarbon (fluidized bed process)

Coated on graphite Pyrolysis takes place at high temperature

Thermal expansion match

Pyrolytic Carbon

23/30

Inert and Biocompatible

Thromboresistant (i.e. resistant to blood clotting) not perfect (still needs anticoagulant)

Good durability

Good wear resistance

Good strength

High fracture toughness (~X20 higher than alumina)

Pyrolytic Carbon

24/30

Allotropes of Carbon

Allotropes: structures with different molecular configurations

25/30

PET and PTFE

PET (polyethylene terephthalate) High melting (Tm=260C) crystalline polymer High tensile strength (~70 MPa) Dacron is a common commercial PET

Available as woven fabric, knit graft

PTFE (poly-tetrafluoroethylene) PE with 4 Hs replaced with Fs High melting (Tm=325C) polymer Very hydrophobic and lubricious catheter, graft Teflon

26/30

Medtronic Hancock II

Aortic/Mitral

Valve Porcine valves or Bovine pericardium Entire porcine aortic root and aorta

(stentless) Stiffened with glutaraldehyde (less

calcification, stable collagen cross-links)

Sewing ring/skirt Wire: Co-Ni alloy, Ni-Ti alloy PET (Dacron), PTFE (Teflon)

Materials in Biological Heart Valves

Most commonly used materials

27/30

Percutaneous Valves Still in early stage of development or infant clinical studies Ability to be delivered to the heart using traditional cardiac

catheterization techniques (balloon catheter), through femoral artery (retrograde) or cardiac apex (anterograde).

Heart does not need to be arrested during the operation no need to use a bypass pump.

Edwards Transcatheter Valve

Cleveland Clinic

28/30

Percutaneous Valves

29/30

What Does it Take to Get a Surgical Valve to Market?

Pre-Clinical In Vitro Testing (ISO 5840, FDA HV Guidance): Hydrodynamic Performance Assessment

Structural Testing/Analysis

Material Assessmentbiocompatibility, material property testing

Pre-Clinical In Vivo Testing (ISO 5840, FDA HV Guidance): Chronic animal study

Clinical Study (ISO 5840, FDA HV Guidance): Non-randomized study against objective performance criteria compiled

from currently marketed heart valves.

Study not designed to show superiority, but rather safety/effectiveness against currently marketed valves.

30/30

Pre-Clinical Hydrodynamic Test

Hydrodynamic performance is compared with a clinically-approved reference valve Steady, Pulsatile Flow Pressure Drop

P vs. Q Steady, Pulsatile Flow Regurgitation and Leakage

Flow Visualization to assess flow patterns through valve

31/30

Pre-Clinical Structural Test

Valve Durability Test (Accelerated Wear) 200x106 cycles simulate five years implant

duration (tissue valves) Performed at 10-15x physiologic heart rate Periodic hydrodynamic testing and visual

examination is performed Valve wear characteristics are compared to

clinically approved reference valve

Valve Stent Structural Assessment Finite Element Stress Analysis (FEA) Fatigue analysis Valve stent fatigue and creep testing

Leaflet Tearing--Pericardial valves

32/30

Pre-Clinical In Vivo Testing

Chronic animal study 20-week implants, usually sheep

Control animals implanted with clinically-approved reference heart valves for comparison

Hemodynamic performance Mean/peak pressure gradients,

effective orifice area, regurgitation, etc.

Assess biological response to device

Pathology, blood work, calcification, thrombus assessment

Biomaterials in Medical DevicesContents of Lectures1_Biomaterials Overview.pdfIntroductionWhat are biomaterials?Study of Biomaterials S&EMetallic BiomaterialsBioCeramicsBioCeramicsPolymer BiomaterialsPolymer BiomaterialsApplications of BiomaterialsCriteria for Biomaterials as ImplantsIssues of Biomaterials in Medical DevicesContdBiocompatibilityAssessing BiocompatibilityIn Vitro Analysis of Cell/Biomaterial InteractionsIn Vivo TestsClinical TrialsBiological Responses to BiomaterialsTypes of Implant-Tissue ResponseWhy do Medical Devices Fail?Mechanisms of Biomaterial BreakdownMechanical FailureFractography: ductile fractureFractography: brittle fracturePhysico-chemical / Chemical FailureMaterial Selection FactorsMedical Device SterilizationMedical Device SterilizationMedical Device SterilizationMedical Device SterilizationEffects of SterilizationEffects of SterilizationEvolution of Biomaterials

2_Medical Devices Overview.pdfMedical DevicesWhat Is a Medical Device?Definition of a Medical Device(by US FDA)Classification of Medical Devices(by US FDA)Classification of Medical Devices(by US FDA)Classification of Medical Devices(by US FDA)Classification of Medical Devices(by US FDA)Getting a Device to MarketSubstantial EquivalencePremarket ApprovalCardiac Rhythm DisordersSpinal ConditionsCardiovascular DiseasesNeurological DisordersUrological and Digestive DisordersDiabetesCombination ProductsRecently Approved Combination ProductsExtra SlidesDefinition of a Medical Device(by EU)Classification of Medical Devices(by EU)

3_Valves.pdfHeart ValvesProsthetic Heart ValveHeartandHeartValvesWhen is it used?Type of Prosthetic Heart ValvesMechanical Heart ValvesMechanical Heart ValvesBiological Heart ValvesBiological Heart ValvesMaterials in Mechanical Heart ValvesYield Strength to Density RatioPyrolytic CarbonPyrolytic CarbonPyrolytic CarbonPET and PTFEMaterials in Biological Heart ValvesPercutaneous ValvesWhat Does it Take to Get a Surgical Valve to Market?Pre-Clinical Hydrodynamic TestPre-Clinical Structural TestPre-Clinical In Vivo Testing

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Biomaterials in Medical Devices - Homepage | …didattica.uniroma2.it/assets/uploads/corsi/144507/Medtronic.pdf · Biomaterials in Medical Devices Eunsung Park, ... • Disadvantages