Percutaneous Closure Percutaneous Closure of Patent Foramen of Patent Foramen

OvaleOvale

Sponsors:Sponsors:Kung Ming Jan, M.D., Ph.D.Kung Ming Jan, M.D., Ph.D.Judah Weinberger, M.D., Ph.D.Judah Weinberger, M.D., Ph.D.Columbia University Medical CenterColumbia University Medical Center

Department of CardiologyDepartment of Cardiology

Project TA: Jeffrey Garanich, Ph.D. Project TA: Jeffrey Garanich, Ph.D.

Design Team:Ali SternDmitry OulianovDolores MirandaHenry QaziSafiya Arif

The City College of New York / Department of Biomedical Engineering

Prenatal Prenatal oxygenation of oxygenation of blood bypasses blood bypasses lungs.lungs.

Oxygenated blood Oxygenated blood passes from right passes from right to left atrium to left atrium through the through the foramen ovale foramen ovale (FO).(FO).

Fetal circulation

Fetal CirculationFetal Circulation

•Septum primum and secundum overlap.

•Septa create an opening to allow direct shunting of fetal blood.

Prenatal Septal Prenatal Septal DevelopmentDevelopment

Following birth the P of Following birth the P of each chamber changes.each chamber changes.

P changes force septum P changes force septum primum to close over primum to close over septum secundum.septum secundum.

In a period of 1-2 weeks In a period of 1-2 weeks 70% of population have 70% of population have fusion of septa primum fusion of septa primum and secundum.and secundum.

Neonatal Septal Neonatal Septal DevelopmentDevelopment

The condition in which The condition in which the septa fail to seal the septa fail to seal over and remain over and remain patent is known as patent is known as ASD. ASD.

ASD is an opening ASD is an opening (hole) between right (hole) between right and left atria. and left atria.

Atrial Septal DefectAtrial Septal Defect

Patent Foramen OvalePatent Foramen Ovale

PFO, a type of PFO, a type of ASD, is a flap-ASD, is a flap-like opening like opening between the between the atrial septa atrial septa primum and primum and secundumsecundum

Clinical NeedClinical Need

PFO is present in 20-25% of PFO is present in 20-25% of the populationthe population

PFO has been associated PFO has been associated with:with: MigrainesMigraines Cryptogenic strokes Cryptogenic strokes Systemic embolismSystemic embolism

Migraine is a vascular headacheMigraine is a vascular headache Over 2,500,000 people in the U.S. have at Over 2,500,000 people in the U.S. have at

least one migraine weekly, with a lifetime least one migraine weekly, with a lifetime prevalence of 18%prevalence of 18%

PFO are related to Migraines if paradoxic PFO are related to Migraines if paradoxic embolism causes headacheembolism causes headache

MigraineMigraine

Cryptogenic strokesCryptogenic strokes

There are 700,000 strokes per year in the There are 700,000 strokes per year in the U.S.U.S.

30-40% of these are cryptogenic30-40% of these are cryptogenic

40-70% of cryptogenic strokes are PFO 40-70% of cryptogenic strokes are PFO relatedrelated

84,000-196,000 strokes per year in the 84,000-196,000 strokes per year in the United States are by paradoxical embolism United States are by paradoxical embolism due to PFOdue to PFO

Treatment OptionsTreatment Options

Medical TreatmentMedical Treatment

Open heart Open heart surgery to close surgery to close the PFO the PFO

Percuteneous Percuteneous closure of the PFOclosure of the PFO

CardioSealCardioSeal

2 Double 2 Double Umbrella Umbrella implantimplant

MP35N MP35N FrameworkFramework

Dacron Dacron Sizes: 17-33mmSizes: 17-33mm

AmplazterAmplazter

Self Self expandableexpandable

Short Short connecting connecting waistwaist

Nitinol WiresNitinol Wires Sizes: 4-38mmSizes: 4-38mm

Amplazter DeliveryAmplazter Delivery

DisadvantagesDisadvantages

Designed for ASDDesigned for ASD Large surface AreaLarge surface Area Thrombus formation Thrombus formation Reduced Reduced

Endothelialization Endothelialization Poor AppositionPoor Apposition Device FractureDevice Fracture Device EmbolizationDevice Embolization

Seals PFO only Consists of two components

Delivery unit Means of closure

Size requirements Delivery size: 3 - 4 mm diameter Deployment size: 3.6 x 4.2 cm Seals area of 8 mm radius around PFO

Biocompatibility Immunological response Thrombogenic response

Single use

Required SpecificationsRequired Specifications

Electrical isolation Isolate main voltage source

Prevent current leakage

Current limits Direct current < 1 μA

Alternating current < 0.4 μA

Mechanical forces

Structural flexibility

Mechanical & Electrical Mechanical & Electrical StabilityStability

Easily operable

Cost efficient

Biodegradable

Degradation time

Particle size

Visible by ultrasound

Non-magnetic

Desired SpecificationsDesired Specifications

In Vitro Reaction to environment

Fatigue test

Maneuverability

Catheter-device integrity

In Vivo*

Dog testing

Human testing

*Evaluation may not be performed in the scope of the project

Device EvaluationDevice Evaluation

ConceptsConcepts

Glue or collagen plugsGlue or collagen plugs Magnetic suturingMagnetic suturing Energy welding devicesEnergy welding devices Staple pins/suturesStaple pins/sutures ScaffoldScaffold Clipping deviceClipping device Intra atrium deviceIntra atrium device Coiled suturing deviceCoiled suturing device ““Sutura” modelSutura” model

Hooked Scaffold ImplantHooked Scaffold Implant

Polyester scaffold Polyester scaffold Advantages:Advantages:

Material Degradation into Material Degradation into H2O & CO2H2O & CO2

Disadvantages :Disadvantages : Material: too stiff for Material: too stiff for

deliverydelivery

Intra atrium device (IAD)Intra atrium device (IAD)

Advantages:Advantages: Minimal amount of Minimal amount of

foreign material in the foreign material in the bodybody

Does not require exact Does not require exact positioningpositioning

Disadvantages:Disadvantages: Material selection:Material selection: Complicated knot Complicated knot

delivery methoddelivery method

Coiled needleCoiled needle

Components: coiled Components: coiled needle, 16mm base needle, 16mm base unitunit

Advantages:Advantages: Does not require exact Does not require exact

positioningpositioning Disadvantages:Disadvantages:

Complicated mechanicsComplicated mechanics Requires electrical Requires electrical

energyenergy Complicated knot Complicated knot

delivery methoddelivery method

Sutura ModelSutura Model Suturing deviceSuturing device

Components: 2 retractable arms, Components: 2 retractable arms, thread attached, 2 needles, handlethread attached, 2 needles, handle

Advantages:Advantages: Existing device provides successful Existing device provides successful

mechanismmechanism Disadvantages:Disadvantages:

Complicated manufacturing Complicated manufacturing

Clipping DeviceClipping Device

Advantages:Advantages: Procedure using the Procedure using the

device is reversible device is reversible in case of failurein case of failure

Simple deployment Simple deployment mechanismmechanism

Disadvantages:Disadvantages: Requires precisionRequires precision Material propertiesMaterial properties

AcknowledgementsAcknowledgements

Kung Ming Jan, M.D., Ph.D.Kung Ming Jan, M.D., Ph.D. Judah Weinberger, M.D., Ph.D.Judah Weinberger, M.D., Ph.D. Columbia University Medical CenterColumbia University Medical Center Department of CardiologyDepartment of Cardiology

Project TA: Jeffrey Garanich, Ph.D. Project TA: Jeffrey Garanich, Ph.D. Robert Sommer, M.D., Ph.D.Robert Sommer, M.D., Ph.D.