WO2005037111A2 - Pediatric congenital heart defect repair model - Google Patents

Abstract

The present invention is directed to a model for teaching or illustrating surgical and/or medical technique, and having a base component representing tissue or an organ and serval components structured and arranged to be couplable to and detachable from the base component and/or to each other, to illustrate different positions of the components with respect to one another representing different phases in surgical and/or medical techniques.

Description

PEDIATRIC CONGENITAL HEART DEFECT REPAIR MODEL

BACKGROUND OF THE INVENTION

The present invention is directed to a model for teaching medical and surgical

procedure. More particularly, the present invention provides a model for effectively

teaching complicated surgical procedure such as cardiac surgery.

Versatility of medical and surgical procedure has tremendously increased in

recent years with it now being quite possible to treat certain medical ailments and

defects that, a few years ago, were considered hopelessly untreatable. For example,

it is now possible to surgically repair the congenital heart defect of hypoplastic left

heart syndrome in which an infant is born with an insufficiently developed left

ventricle in addition to other cardiac defects such as a defective aortic valve.

Previously, such infants only lived a short time after birth, there being no known way

to repair this defect. However, it has now been discovered that by performing a

series of surgeries, starting almost immediately after birth and concluding at about

the age of 7, this defect can be repaired with resulting cardiac functioning

approximating that of a normally formed heart. The oldest living patient who had

suffered from this defect and underwent the series of surgeries for repair has just

reached adulthood, confirming the success of this surgical procedure.

Accordingly, such surgical procedure will be increasingly adopted to repair

such congenital cardiac defect in addition to other severe medical and cardiac

defects, congenital or otherwise. With increasing use of such complicated surgical

procedure, it becomes increasingly important to properly instruct surgical and

medical practitioners, in addition to support staff such as nurses, of the proper

surgical technique and procedure. Ideally, it should be possible to permit such personnel to practice with a model, e.g., of a heart, to gain understanding of the

various steps required to repair a defect such as hypoplastic left heart syndrome.

Previously, however, no such effective teaching model had been developed.

While several models exist for teaching various medical and surgical procedures,

e.g., in a classroom, models for teaching rather complicated surgical procedure have

not yet been provided. For example, U.S. Patent no. 5,634,797 to Montgomery

discloses a teaching aid constituted by a doll containing realistic replaceable heart

models simulating a variety of cardiac defects, including mitral valve atresia disorder

and hypoplastic left ventricle (column 5, lines 10-50 and Figs. 10 and 23). These

heart models can be attached to a pump unit to provide realistic flow of sonographic

fluid therethrough, the goal being teaching the practice of sonography in recognizing

heart disorders (column 6, lines 50-64). Thus, Montgomery is directed to teaching a

diagnostic ^'technique and not surgical procedure.

Accordingly, it is an object of the present invention to improve teaching of

medical and/or surgical procedure, especially with respect to complicated surgical procedures that have recently and successfully been developed, e.g., repairing hypoplastic left heart syndrome.

It is also an object of the present invention to provide a teaching model which can easily be used to teach a variety of surgical techniques in various stages.

It is a further object of the present invention to improve surgery, medical

treatment and care- of patients by improving instruction in medical and/or surgical procedure in accordance with a teaching model. SUMMARY OF THE INVENTION These and other objects are attained by the present invention which is directed to a model for teaching or illustrating surgical and/or medical technique, comprising a base component representing tissue or an organ and several

components structured and arranged to be couplable to and detachable from the base component and/or to one another, to illustrate different positions of the components with respect to one another representing different phases in the surgical

and/or medical technique. The components constituting the model can be formed

from ceramic, clay or synthetic material such as plastic, with male/female snap

couplings being formed at respective ends thereof to allow coupling, detaching and

re-coupling of the various components with one another in the different positions. In particular, the base component of such teaching model represents the

heart, with other components being tube-shaped and constituting veins, arteries or

surgical material. These various components are preferably color-coded to facilitate

illustration of various surgical and medical techniques. In particular, the inventive

model can be used to illustrate the sophisticated surgical repair of hypoplastic left

heart syndrome, although other surgical techniques, e.g., on the heart, can be illustrated and taught with the inventive model.

The inventive model greatly facilitates understanding of surgical procedure

and is effectively used to instruct students in complicated surgical technique that is

continuously evolving and being improved. Therefore, medical and surgical personnel can be successfully instructed with the result being improved performance

by such personnel both during such surgery and in the resulting care of the patients.

Improved recovery by such patients is thereby naturally attained.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described in greater detail with reference to

the accompanying drawings in which

Fig. 1 is an exploded left anterior oblique view of a teaching model for a heart

in accordance with the present invention and illustrating a pre-operative defective

condition of the heart; Fig. 2 is a left anterior oblique view of the assembled heart model shown in Fig. 1 ; Fig. 3 is a right anterior oblique view of the heart model shown in Figs. 1 and

2 and with the anterior portion of the myocardium removed;

Fig. 4 is a posterior view of the heart model shown in Fig 3;

Fig. 5 is an exploded, left anterior oblique view of a teaching model and

illustrating a first surgery or stage in a surgical procedure for repair of the defective heart;

Fig. 6 is a right anterior oblique view of the heart model shown in Fig. 5 and

with the anterior portion of the myocardium removed;

Fig. 7 is an exploded left anterior oblique view of a heart model similar to 5

and illustrating an alternative procedure for repair of a defective heart in the first surgical stage; Fig. 8 is an exploded left anterior oblique view of a heart model and

illustrating a second surgery or surgical state for the repair of a defective heart;

Fig. 9 is a posterior view of the heart model shown in Fig. 8;

Fig. 10 is a posterior view of a heart model illustrating a third surgery or

surgical stage in the repair of a defective heart; Fig. 11 is an exploded, left anterior oblique view of the heart model shown in

Fig. 10; Fig. 12 is an exploded, left anterior oblique view similar to Fig. 11 and

illustrating an alternative procedure for the repair of the defective heart in the third

surgical stage; and Fig. 13 is a right anterior oblique view of the heart model shown in Fig. 12;

Fig. 14 schematically illustrates coupling of two components by tongue-in-

groove arrangement in accordance with the inventive model;

Fig. 15 schematically illustrates concentric coupling of two components

forming part of the inventive model;

Fig. 16 illustrates the inner concentric sliding member shown in Fig. 15;

Fig. 17 illustrates part of the outer concentric member of Fig. 15 with the inner

concentric member slidably arranged therein;

Fig. 18 illustrates a posterior plastic member forming the outer concentric

member of Fig. 15;

Fig. 19 illustrates the inner sliding member of Fig. 16;

Fig. 20 illustrates an anterior plastic member forming the outer concentric member of Fig. 15; Fig. 21 illustrates a male pin member for coupling a component in accordance

with the inventive model; Fig. 22 illustrates a hollow female pin member for receiving the male pin

member of Fig. 21 ; Fig. 23 schematically illustrates coupling of tubular components forming, e.g.,

a blood vessel in the inventive model, with the pin members shown in Figs. 21 and

22; Figs. 24 and 25 respectively illustrate a tubular component forming a blood

vessel in accordance with the inventive model before and after filleting;

Fig. 26 schematically illustrates coupling of two adjacent tubular components

through a third substantially cylindrical component in the inventive model;

Fig. 27 illustrates components representing valve leaflets and chordea in the inventive model;

Fig. 28 illustrates components representing valve rings in the inventive model.

Fig. 29 illustrates an anterior view of a teaching model in accordance with the present invention of a normally-developing embryological heart;

Fig. 30 illustrates a right anterior oblique view of a teaching model in accordance with the present invention and showing a further pediatric congenital heart defect;

Fig. 31 illustrates a right anterior oblique view of a teaching model in

accordance with the present invention for yet another pediatric congenital heart defect;

Fig. 32 illustrates a posterior view of the teaching model shown in Fig. 31 ; Fig. 33 illustrates a right anterior oblique view similar to Fig. 31 and showing repair of the pediatric congenital heart defect illustrated in Figs. 31 and 32; Fig. 34 illustrates an anterior view of an exterior of the heart model shown in Fig. 31 and showing one alternative in the repair of the pediatric congenital heart

defect shown in Figs. 31 and 32; Fig. 35 illustrates an anterior view of the exterior of the heart model similar to

Fig. 34 and another alternative in the repair of the pediatric congenital heart defect

shown in Figs. 31 and 32; Fig. 36 illustrates an anterior view of a teaching model in accordance with the

present invention and illustrating still a further pediatric congenital heart defect;

Fig. 37 illustrates a right anterior oblique view of the teaching model shown in

Fig. 36;

Φ Fig. 38 schematically illustrates coupling of components representing arteries in the teaching model in accordance with the present invention; and

Fig. 39 is a view, similar to Fig. 36 and illustrating repair of the pediatric congenital heart defect illustrated in Fig. 36.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Similar components forming the teaching model of the present invention will

be referred to by similar reference numerals or characters in all the illustrated

embodiments or stages.

The teaching model 1 illustrated in Figs. 1 and 2 illustrates a human heart

having a congenital preoperative defect, namely hypoplastic left heart syndrome. In

such condition, the left ventricle 2 of the heart is insufficiently formed or expanded

during fetal development, with the result being presence of a tiny or virtually

nonexistent left ventricle 2 in the heart of a newborn infant. Such defect resulted in

the heart being unable to pump sufficient blood flow through the infant, the tragic

result being failure of the heart within a short time after birth, e.g., not more that a

few weeks. In Figs. 1 and 2, reference numeral 3 denotes the anterior portion of

myocardium while reference numeral 4 denotes the right ventricle, reference

numeral 5 the right atrium, reference numeral 6 the left atrium and reference

numeral 2 the defective left ventricle. Additionally, reference numerals 7-10

respectively denote the right subclavian artery, the right common carotid artery, the

left common carotid artery, and the left subclavian artery. The tricuspid and mitral

valves are respective denoted by reference numerals 11 and 12. Additionally,

reference numerals 13-15 respectively denote the ascending aorta, descending

aorta and left pulmonary artery in Figs. 1 and 2, with reference numerals 16-19

respectively denoting the superior vena cava, brachiochephalic artery, aortic arch and patent ductus arteriosus in Figs. 1 and 2. In Figs. 3 and 4, reference numerals 20, 21 and 15 denote the right

pulmonary artery, the main pulmonary artery, and the left pulmonary artery, with

reference numerals 22-25 illustrating the right upper pulmonary vein, the left upper

pulmonary vein, the right lower pulmonary vein and the left lower pulmonary vein

respectively. The defective congenital cardiac condition illustrated in Figs. 1 and 2

shows a defective, insufficiently formed left ventricle 2 , a defective mitral valve 12

and aortic valve 26 and an atrial septal defect 27, in addition to the patent ductus

arteriosus 19, and a coarctation of the aorta 19a. Additionally, the atrial septal

defect 27 is present between the right and left atria as best seen in the model of Fig.

3. It is this complex combination of anatomic defects that the surgeries shown in the

accompanying heart models are designed to repair and remedy.

Figs. 5-7 show a heart model 1' representing completion of a first or Stage I

surgical palliation for hypoplastic left heart syndrome, also termed Norwood Stage I,

involving patent ductus artereosus ligation. Such surgery takes place roughly 3 to 7

days after birth. In this first surgery, an artificial Gortex graft 28 is applied to the

ascending aorta 13 and aortic arch 18 and which is sutured, in turn, to the root of a

surgically transected main pulmonary artery to create a neoaorta 29. Secondly, an

atrial septectomy is performed to enlarge the atrial septal defect 27 between the the

left 6 and right 5 atria. Thirdly, a modified Blalock-Taussig shunt 30 is connected

between the right subclavian artery 7 and right pulmonary artery 20. Reference

numeral 21 denotes the pulmonary artery root. Fig. 7 illustrates a completed first

surgical stage similar to Figs. 5 and 6, but without the diminuitive ascending aorta

being sutured to a Gortex graft; in this embodiment, a separate artificial Gortex tube 28' is implanted and sutured to interconnect the periductial aortic arch 18 and the

pulmonary artery root 21 , bypassing the diminutive ascending aorta.

Figs. 8 and 9 constitute a heart model illustrating completion of Stage II

surgical palliation for hypoplastic left heart syndrome, which normally takes place

about 6 to 9 months after the initial surgical stage I shown in Figs. 5-7. In this

second surgical stage, a bidirectional cavo-pulmonary shunt or bidirectional Glenn

shunt is created using several large vessels around the heart. More particularly, the

Blalock-Taussig shunt 30 is removed, and the superior vena cava 16 surgically

divided and connected to the right pulmonary artery 20, leaving a superior vena cava

stump 16' which is sutured closed. Reference numeral 32 denotes the inferior vena

cava. Finally, Figs. 10-13 illustrate the third surgical stage usually occurring 5 to 7 years after birth, with Figs. 10 and 11 illustrating cardiac repair by extracardiac Fontan procedure, and Figs. 12 and 13 illustrating repair by intracardiac Fontan procedure. More particularly, the extracardiac Fontan procedure shown in Figs. 10 and 11 has a baffle 33, manufactured, e.g., by synthetic Gortex, interconnecting the inferior vena cava 32 and right pulmonary artery 20. Reference numeral 32' denotes

a sutured inferior vena cava stump with reference numeral 16 denoting the superior

vena cava. Additionally, a fenestration 34 is placed in the Fontan as it passes the

lateral wall of the right atrium to allow for pressure release upon unwanted pressure

buildup in the Fontan. Figs. 12 and 13 illustrate a variant of the third surgery,

namely placement and insertion of the baffle 33' directly into the right atria 5 of the

heart. In this embodiment, the fenestration 34 in the baffle 33' is also provided into the right atria 5, the difference being the native inferior vena cava is not surgically

altered, and the intracardiac Fontan directs blood flow along the interior lateral wall

of the right atrium. The previously sutured-over superior vena cava stump 16' is now

made patent and interconnected into the right pulmonary artery 20. The superior

vena cava stump 16' may have already been sutured to the right pulmonary artery

20, but with its internal orifice covered over in the previous surgical stage.

The illustrated heart models can be manufactured from any suitable

materials, e.g., synthetic plastic such as polyethylene terephthalate, polyvinyl

chloride, etc. An especially preferred material includes the plastic manufactured under the

trade name "Friendly Plastic" by American Art Clay Co., Inc., Indianapolis, Indiana

46222. As shown in the accompanying figures, the various components have been

colored to enhance comprehension of the various surgical steps taking place. In particular, the following components have been color-coded in the following fashion

to enhance teaching comprehension: light blue - the native main pulmonary artery and right and left branch pulmonary arteries; dark blue - the native superior vena cava and inferior vena cava; red - the native aorta (ascending, arch and descending), and native aortic branches (brachiocephalic artery dividing into right subclavian artery and right common carotid artery, left common carotid artery and left subclavian artery); purple - ductus atreriosus; green - any material that is not native to a patient's own anatomy, or is taken from its original anatomical position to be used as part of the surgical reconstruction (e.g., Gortex grafts or patches, donor homograft material, or pericardial tissue used elsewhere as a patch or reconstructive; and white - valve leaflets and chordae tendineae.

Various types of couplings between plastic components can be provided to

illustrate interconnection and detachment of the various veins and arteries to

illustrate the various stages of surgeries as shown, e.g., in Figs. 1-13 for repair of

hypoplastic left heat syndrome. In one type of engagement or coupling as shown,

e.g., in Fig. 14, a recessed groove 35 can be provided in one member with a

corresponding extension 36 provided on a complementary component having a

double thickness in a middle of a slide-in portion 36 and a single thickness rim

protruding from three edges thereof such that the slide-in portion 36 can be slid into

the groove 35 and effectively retained therein. Such coupling or interlocking is

especially advantageous for illustrating coronary artery transplant during arterial

switch or Ross. The double layer of plastic or other acceptable, e.g., synthetic

material, is provided with the slightly indented groove along sides and a bottom of

the cut-out shape. The groove 35 accepts the single-thickness rim such that the

double thickness of the slide-in portion sits exactly into the double layer of plastic that accepts the cut-out.

In an alternative form of coupling as shown, e.g., in Figs. 15-17, a sliding

door/window type coupling of interlocking components can be provided to illustrate

repair of atrial septal defects, ventricular septal defects and fenestration in the

teaching heart model, in such interlocking, a single layer of plastic 37 will slide in between the outer layers to represent a "defect" in a wall of a heart. Such movable

plastic layer 37 will have a protruding handle 38 to permit sliding back and forth. A

double thickness wall 39 representing the wall of heart muscle can be provided with

a space in between to accept the sliding door 37. A hole 40 is provided through one

of the lateral walls to pe'rmit sliding by grasping the handle 38.These concentrically arranged components

have been illustrated with substantially rectangular cross-sections, but may take any

geometric shape in accordance with the claimed invention.

Figs. 18-20 schematically illustrate manufacturing the sliding doors with Fig. 18 denoting posterior plastic 39', Fig. 19 the middle sliding door 37 and Fig. 20 the

anterior plastic 39".- The outer walls 39', 39" can be assembled by simple shape-

fitting or molding together. Plastic pins 41 and acceptor pins 42 which can be used

to couple components illustrating, e.g., the arterial switch, neoaorta attachment to

the pulmonary artery base, bidirectional cavopulmonary shunt and Fontan, are

shown in Figs. 21-23 with Figs. 23 schematically illustrating coupling of respective

tubing through these pins mounted at ends of the respective tubing. The pin 41

shown in Fig. 21 comprises a notch 43 and a magnet 44 embedded in a top portion

thereof. The pin 42 shown in Fig. 22 is hollow, designed to receive the respective pin

41 shown in Fig. 21 , and is also provided with an internal protrusion 45 designed to

catch in the notch 43 of the embedded male member pin 41.

Figs. 24 and 25 respectively illustrate assembly of a tube 46 constituting one

of the vessels, e.g. an artery or vein. Fig. 24 illustrates a perspective view of a tube

fully closed, e.g., prior to filleting to illustrate surgical opening. Fig. 25 illustrates the same tube after opening or filleting to illustrate connection or disconnection during

the various surgical procedures as illustrated above. Pliable material, e.g., a metal

sheet, can be embedded within a piece of clay or plastic to enhance shape retention

of the tube both before and after filleting. Fig. 26 is a schematic posterior view illustrating sliding coupling of parts

illustrating coupling of a Blalock-Taussig shunt 30 in the inventive model. The shunt

component itself, illustrated by a cylindrical piece, contains plastic or metal pegs 47,

47' protruding from opposite ends thereof and arranged to slide into and mate with

corresponding notches 48, 48' provided in adjacent components illustrating the

arteries. Valve leaflets and chordea can be constituted by white-colored paper-like

material glued to valve rings and papillary muscles as illustrated, e.g., in Fig. 27

while the valve rings 50 themselves can be constituted by thin metallic rings as illustrated in Fig. 28.

The invention has been illustrated in Figs. 1-13 with respect to teaching repair

of hypoplastic left heart syndrome. However, models in accordance with the claimed invention can be prepared to teach cardio-surgical technique for repairing any number of cardiac abnormalities, such as transposition of the great arteries, atrio-

ventricular canal, total anomalous pulmonary venous return, partial anomalous

pulmonary venous return, double outlet right ventricle, tetrology of fallot, atrial septal

defect and ventricular septal defect. Other medical and surgical techniques can be

taught by the inventive models such as sites of cannulation for cardiopulmonary

bypass and extracorporeal membrane oxygenation, fetal circulation and Ross procedure. While the inventive model has been illustrated and described with detachable

and interchangeable components to show the various progressions in cardiac

surgery, it is also possible within the scope of the present invention to provide a

series of fixed models showing each of the surgical stages without provision of

attachable and removable components. For example, four separate heart models

could be prepared to show the following conditions: pre-operative defective condition analogous to Figs. 1-4; first surgical stage analogous to Figs. 5-7; second surgical stage analogous to Figs. 8 and 9; and third surgical stage analogous to Figs. 10-13.

These four respective models could be provided with a minimum number of

removable components, e.g., just a detachable cover 3 representing the anterior portion of the myocardium. Such models can also be manufactured from plastic, or

additionally from other material such as ceramic or clay.

For example, the components forming the inventive heart model can be

molded from plastic, e.g., "Friendly Plastic" pellets available from American Art Clay

Co., Inc., Indianapolis, Indiana.

The inventive model can also be utilized for teaching surgical repair of other

types of pediatric congenital heart defects. For example, Fig. 29 is an anterior view

of a model 100 illustrating the normally-developing embryological heart having D-

ventricular cardiac loop formation, in which the four chambers within the heart are

formed as a single straight tube; this model illustrates the aorta 101 , pulmonary

artery 102, truncus arteriosus 103, bulbus cordis (right ventricle) 104, left ventricle 105, atrium 106 and sinus venosus 107, with arrows A and B illustrating the direction

of looping. Fig. 30 illustrates the condition 100' of both atrial and ventricular septal

defects. The atrial septal defect involves a hole 108 occurring in the wall of the

septum separating the left and right atria of the heart; the ventricular septal defect

can involve a large opening 109 between the heart's muscles. This particular model

also illustrates the superior vena cava 110, aorta 111 , pulmonary artery 112 and

inferior vena cava 113. Atrial and ventricular septal defects need not both occur at

the same time in a patient; only one or the other can occur. Additionally, the atrial

and ventricular septal defects can occur at different locations within the atrium or

ventricle.

Figs. 31 and 32 illustrate the condition of tetrology of fallot which includes the

malformations of an overriding aorta 114, a ventricular septal defect 115, right

ventricular hypertrophy 117 and right ventricular outflow tract obstruction 116.

Pulmonary veins 118, 119 and the pulmonary artery 120 are illustrated in Fig. 32. In

this regard, Fig. 33 illustrates two aspects of repair of tetrology of fallot, namely (1 )

ventricular septal defect repair 122, and (2) re-sectioning of the thickened

infundibular muscle 121. These repairs can take place by one of two alternative

procedures illustrated in Figs. 34 and 35.

More specifically, one option for repair is cutting the ring (annulus) of the

pulmonary valve and expanding the size of the ring and width of the pulmonary

artery with a trans-annular patch 123, as viewed from outside the heart as shown in

Fig. 34. Another option for repair involves opening the pulmonary artery and reaching down through the annulus of the pulmonary valve to resect the tnick

muscle of the infυndibulum by making a cut through the pulmonary artery and

suturing 124 after completion, and repair the ventricular septal defect with a patch as

shown in Fig. 35. The thick part of the inside of the anterior myocardial muscle is

also resected, and repaired with an infundibular patch 125. Figs. 36 and 37 illustrate the pediatric congenital condition of D-transposition

of the great arteries where the aorta 126 is connected to the right ventricle 127 and

pulmonary artery 128 to the left ventricle 129. An atrial septal defect 130 also

occurs. A moderator band 131 and papillary muscle 132 are illustrated in Fig. 36

with the root 133 of the pulmonary artery 136 illustrated in Fig. 37. Fig. 39 illustrates

the repair of this condition where the coronary arteries 134, 135 are moved from the

root 137 of the aorta 126 to the root 133 of the pulmonary artery 128 or 136. More

specifically, the pulmonary artery 139 is transplanted onto the native aortic root 137,

with the aorta 126 transplanted onto the native pulmonary root 133. In addition, the

pulmonary artery 128 or 136 is moved anteriorly when transplanted onto the native

aortic root 137.

The coronary arteries 134, 135 are transplanted to the native pulmonary

artery root 133. More specifically, as shown simultaneously in Fig. 38, de-coupling

of these components, namely the right coronary artery 135 with ostium button 135'

and left coronary artery 134 with ostium button 134' from the native aortic root 137,

prepares re-implantation of coronary arteries 134, 135. Patch location of coronary artery ostium 134', 135' with buttons is illustrated in Fig. 39 which also shows the native pulmonary

artery root 133 originating from the left ventricle 138 and the superior vena cava 139.

Repair of other pediatric congenital heart defects such as total anomalous

pulmonary venous connection, atrioventricular canal defect, coarctation of the aorta

and double outlet right ventricle and double outlet left ventricle, can be illustrated by

the inventive teaching models.

The preceding description of the present invention is merely exemplary and

not intended to limit the scope thereof in any way.

Claims

WHAT IS CLAIMED IS:

1. A model for teaching or illustrating surgical and/or medical technique,

comprising a base component representing tissue or an organ, and several components structured and arranged to be couplable to and

detachable from the base component and/or to one another, to illustrate different

positions of the components with respect to one another representing different

phases in the surgical and/or medical technique.

2. The model of claim 1 wherein the components are formed of ceramic, clay,

or synthetic material such as plastic.

3. The model of claim 2 wherein the components are formed of plastic and

comprise male/female snap couplings at respective ends thereof to allow coupling,

detaching and re-coupling of the various components with one another in the

different positions.

4. The model of claim 1 wherein the base component comprises a heart having containing ventricles and the other components are tube-shaped and represent veins or arteries.

5. The model of claim 2 wherein the base component and other components are color-coded to facilitate illustration or teaching of the surgical and/or medical

technique.

6. The model of claim 4 wherein the base components and the components representing the veins or arteries are color-coded to facilitate illustration or teaching

of the surgical and/or medical technique.

7. The model of claim 4, wherein the base components and other

components are structured and arranged to be couplable, detachable, and

recouplable to each other in the various positions to illustrate various stages during

cardiac surgery or a series of different cardiac surgeries for repair of the heart.

8. The model of claim 7, wherein the base component and other components

are structured and arranged to illustrate various surgeries for repair of hypoplastic

left heart syndrome.

9. The model of claim 1 , comprising components structured and arranged to

be removably coupled together by tongue-in-groove arrangement.

10. The model of claim 1 , comprising components structured and arranged to

be removably coupled together by concentrically and slidably arranged components

with respect to one another.

11. The model of claim 10, wherein an outer hollow one of said concentric

components is provided with a lateral opening and an inner one of said concentric

components is provided with a handle extending through said lateral opening of said

outer concentric component to allow said inner component to be slid with said outer

component.

12. The model of claim 1 , comprising components structured and arranged to

be removably coupled together by complementary-shaped male and female pin members.

13. The model of claim 12, wherein said pin members comprising respective

complementary indentations and protrusions to facilitate removable coupling in a snap-fitting manner.

14. The model of claim 1 , comprising at least one tubular member structured

and arranged to retain shape both before and after filleting.

15. The model of claim 1 , comprising at least one substantially cylindrically-

shaped member have pegs protruding from opposite ends thereof and structured

and arranged to removably seat in notches provided in other coupling members to

couple two such members together therethrough.

16. A method for teaching cardiac surgical technique comprising the steps of providing a heart model showing a base heart component containing atria and

ventricles and tubular members interconnected with the base heart component and

representing various arteries and veins, and detaching and interconnecting the various tubular members with one another

to illustrate various cardiac surgeries or stages in a surgery

17. The method of claim 16, wherein the various components are color-

coded.

18. The method of claim 16, wherein the various components are structured

and arranged to be couplable to and detachable from one another by

complementary-shaped locking members affixed thereto.

19. The method of claim 16 comprising several base heart components and

illustrating ^"surgical repair of hypoplastic left heart syndrome.

20. A series of models for teaching or illustrating surgical or medical

technique of the heart, comprising

A first model illustrating pre-operative defective condition of the heart; a second model illustrating a first stage in surgical repair of the heart; a third model illustrating a second stage in the surgical repair of the heart; and a fourth model illustrating a third stage showing completion of the surgical

technique.

21. The series of Claim 20, wherein said four models illustrate the stages in

surgical repair of hypoplastic left heart syndrome.

22 The model of Claim 1, structured and arranged to illustrate surgical repair

of at least one of the pediatric congenital heart conditions of atrial septal defect and

ventricular septal defect, tetrology of fallot and transposition of the great arteries, r total anomales pulmonary venous connection, atrioventicular canal defect,

coarctation of the aorta and double outlet right ventricle and double outlet left

ventricle.