Artificial Heart Valve | Heart Valve Replacement | Material used | Manufacturing

Artifiial heart valve textile sphere

Aayushee Ghorpade

Veermata Jijabai Technological Institute,Mumbai


The basis of human existence, ‘The Human Heart’, plays a very crucial role in deciding the functioning of the entire body. It serves as the significant organ that pumps to circulate blood throughout the body.The heart comprises four valves, each in the one chamber of the heart, which maintain one-way blood flow through your heart. Each valve has flaps which open and close once during each heartbeat.

Types of heart valves :

heart valves textile sphere

Tricuspid Valve :

It has three leaflets or cusps and separates the top right chamber (right atrium) from the bottom right chamber (right ventricle).

Pulmonary Valve (or Pulmonic Valve) :

It has three leaflets and separates the right ventricle from the pulmonary artery.

Mitral Valve :

It has two leaflets and separates the top left chamber (left atrium) from the bottom left chamber (left ventricle).

Aortic Valve:                                                                                        

It has three leaflets, unless it's abnormal from birth, i.e., bicuspid aortic valve and separates the left ventricle from the aorta.

Problems Related to Dysfunctioning of Heart Valves :

As sensed by a stethoscope, heart valve problems are basically identified by the presence of a quirky sound or murmur  like a whooshing noise as blood flows sequentially from one chamber to the next, or like an extra click when a blood flows backwards. Symptoms of valve disease. Other symptoms include  chest pain, fatigue, lightheadedness, shortness of breath etc.

Heart valve problems include :

  • Stenosis : It is the narrowing or stiffening of the valve which prevents enough blood supply from flowing through.
  • Regurgitation : It occurs when the valves allow blood to flow backward into the chamber.
  • Prolapse: It occurs due to improper closing of valve leaflets.
  • Atresia: It occurs when a valve is improperly formed or is missing(by birth).

The heart valve dysfunctioning can take place in any of the four valves. Some of the following are tricuspid atresia, tricuspid regurgitation, tricuspid stenosis,pulmonary valve stenosis, pulmonary valve regurgitation, mitral valve prolapse, mitral valve regurgitation, mitral valve stenosis, aortic regurgitation or aortic insufficiency), aortic stenosis.


To overcome heart valve impairment, surgical  treatments involve either repairing of the valve or its replacement influence on the basis of type of valve disease,age and other medical conditions.Valve replacement is performed either by mechanical or tissue heart valves.

Mechanical valve

Material and fibres used :

  • Rigid materials and fibres such as nylon,UHMWPE (ultra high molecular weight polyethylene), PTFE (polytetrafluoroethylene, polyoxymethylene), silicone rubber, stellite (cobalt-chromium-molybdenum-nickel alloys), titanium, methacrylate and stainless steel. However, silicone rubber results in deterioration and swelling.
  • As a replacement of the original valve, the mechanical valve comprises two leaflets and a metal ring which is enclosed by a ring of knitted fabric and sewn onto the heart in place of the original valve.
  • Even though being durable, they aid in the formation of blood clots leading to lifelong blood thinning medication. These valves should be avoided in women of child-bearing age and those with a high risk of bleeding.

Tissue valve

  • A biological substitution of the original valve with biological or bio prosthetic valves composed of animal tissue (such as porcine (pig), bovine (cow) and equine (horse))  or human tissue (from a donor human heart, known as an allograft or homograft) is accomplished and then fixed with a preserving solution.
  • The Tissue valve is encircled by a ring of knitted fabric that is sewn onto the heart.
  • Tissue valves have the perk of avoidance of lifelong blood thinning medication for preventing the development of blood clots. On the contrary they have relatively poor durability as compared to mechanical valves, requiring a re-operation in 10 to 20 years.

Fabrication of Mechanical and Tissue Valves :

Materials used :

Materials used in the fabrication of mechanical heart valves must inculcate favorable mechanical properties and biocompatibility. Pyrolytic carbon is the foremost and leading biomaterial used for the fabrication of mechanical heart valves.

Properties for fabrication :

Properties that assist the use of Pyrolytic carbon are enhanced strength (300–400 ​MPa) and resistance to surface thrombosis and fatigue.However, pyrolytic carbon is brittle which is similar to that of brittle plastics such as polystyrene.

Polymeric cardiac valves :

In contrast to biological or tissue valves, polymeric valves are custom designed to accomplish the required specifications and be less prone to failures.

Polymers and fibres used : 

Polyethylene(PE) or polymethyl methacrylate (PMMA),polyurethane, polytetrafluoroethylene(PTFE) poly(styrene-b-isobutylene-b-styrene), biodegradable elastomers, and different types of hydrogels.

Properties :

  • Rigid polymers with robust mechanical properties to retain structural integrity over repeated cyclic loading–unloading along with self recovery.
  • High toughness and negligible creep.
  • Life-long anticoagulation, and modulus nearly similar to native valve.


Materials used : Manufactured by the casting of PGA and PLA seeded with mesenchymal stem cells, Decellularized matrix made from fibrin gel and PHO seeded with vascular endothelial cells, fabrication for the replacement of pulmonary valves is achieved.

Similarly, electrospinning is used for the manufacturing of fabrications using 2-Ureido-4[1H]-pyrimidinone-polyester urethane,P4HB and gelatin and Poly(l-lactide-co-D,l-lactide) nanofibers seeded with adult stem cells driven from bone marrow as polymers.

Manufacturing of Fabrication for Artificial Heart Valves :

Processes involved in the manufacturing of Artificial heart valves include :


Molding is the most extensively fabrication technique.In this method, the polymeric solution or melt is set into a mold of desired geometry, allowed to solidify and then released from the mold after a certain time.The fabrication process of molding is generally very mild leading to high viability for embedded cells.

Multi-material structures are also developed by a multistep approach in which different polymers are introduced into the mold at different time intervals. Practical limitations to molding methods for the construction of multiple layer fabrication with polymers of different properties and cell types is that each material phase will exhibit isotropic properties, in contrast to the native heart valves that are anisotropic in each phase. Also, the opening and closing of the mold several times leads to complications and discrepancy in manufacturing.

For example, multicomponent heart valves made of fibrin and elastin-like gels were created wherein different types of cells and materials were employed to reconstruct the heterogeneity of the native heart valves.


As a substitution to drawing, electrospinning is a highly versatile fabrication technique that has been used to obtain artificial heart valves with desirable macroscopic shape and size, mechanical properties, heterogeneity and manufacture fibers from sub-micron to nanometer fibers from a wide range of polymeric materials.

The microfibril structure of electrospun scaffolds support the myocardial tissue as it resembles its hierarchical structure.In contrast to molding,the alignment of electrospun microfibers can be controlled to create mechanical anisotropy as in the native heart valve.

In this method electrodes with either insulating or conductive patterns,having variable and controllable deposition time are employed. However,these electrodes are embodied by electrospun scaffolds due to the presence of organic solvents and high voltages.

An added advantage of electrospinning is that it incorporates suture-free heart valves to integrate the wall scaffolds into valved  geometries.

3D Printing Technology for biofabrication :

  • However, 3D Printing being used for bio fabrication is an emerging technology of the nearing future.
  • There are three methods of 3D bio fabrication : Laser-induced forward transfer, inkjet, and extrusion printing.
  • 3D Printing Technologies require stiff hydrogels for fabrication whereas cell culture is carried out in substances having low viscosity and low stiffness,  resulting in shapeless structures.

References :

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