Heart

Heart

  • Submitted By: gennie23
  • Date Submitted: 12/08/2008 2:32 AM
  • Category: English
  • Words: 3072
  • Page: 13
  • Views: 445

An artificial heart valve is a device which is implanted in the heart of patients who suffer from valvular diseases in their heart. When one or two of the four heart valves of the heart have a malfunction, the choice is normally to replace the natural valve with an artificial valve. This requires open-heart surgery.
Valves are integral to the normal physiological functioning of the human heart. Natural heart valves are structures which have evolved a form which meets their functional requirements, which is to induce largely unidirectional flow through them. Natural heart valves may become dysfunctional due to a variety of pathological causes. Certain heart valve pathologies may necessitate the complete surgical replacement of the natural heart valves with heart valve prostheses.
Contents
• 1 Types of heart valve prostheses
• 2 Mechanical valves
o 2.1 Types of MHV's
o 2.2 Durability
o 2.3 Fluid mechanics
o 2.4 Blood damage
• 3 Biological valves
• 4 Functional requirements of heart valve prostheses
• 5 Design challenges of heart valve prostheses
• 6 Typical configuration of a heart valve prosthesis
• 7 MHV manufacturers
• 8 External links

Types of heart valve prostheses
There are two main types of artificial heart valves: the mechanical and the biological valves.
• Mechanical heart valves
o Percutaneous implantation
 Stent framed
 Not framed
o Sternotomy/Thoracotomy implantation
 Ball and cage
 Tilting disk
 Bi-leaflet
 Tri-leaflet
• Biological heart valves
o Allograft/isograft
o Xenograft

Mechanical valves


A mechanical artificial heart valve with a pivoting disc.
Mechanical heart valves are prosthetics designed to replicate the function of the natural valves of the human heart. The human heart contains four valves: tricuspid valve, pulmonic valve, mitral valve and aortic valve. Their main purpose is to maintain unimpeded forward flow through the heart and from the heart into the major blood...

Similar Essays