Written with A. Marc Gillinov, M.D.
Department of Cardiovascular and Thoracic Surgery
Valve Surgery - the past
As long ago as 1400, Leonardo de Vinci described in great detail the anatomy of the aortic and mitral valves. But it wasn't until the 1950s, that great strides were made in the journey to develop surgical treatments for those with valve disease. These included innovations such as the heart-lung machine, the use of bioprosthetic (pig and calf) valves and the first aortic valve surgery.
Over the past years, many more advances have improved outcomes for those who have valve disease and need valve repair. These include:
- improved diagnostic techniques
- better timing for surgical intervention
- the introduction of valve repair,
- improvements in replacement valves, and
- improvements in surgical techniques, most notably, the introduction of minimally invasive surgery
Valve Surgery - The present: Improvements in surgical technique for valve surgery
Minimally invasive valve surgery
In 1996, Cleveland Clinic surgeon Delos M. Cosgrove, M.D., performed the world's first minimally invasive heart valve surgery. Since that time, improvements in the type of incision and surgical techniques have led to a proven, successful minimally invasive approach to valve surgery.
Chest wall incisions used for heart surgery
Median sternotomy incision
Minimally invasive approach: partial upper sternotomy
Minimally invasive approach: small right thoracotomy incision
There are a variety of minimally invasive approaches. We favor a small skin incision and a partial sternotomy as this provides excellent access to both aortic and mitral valves, enabling the surgeon to achieve as complete and successful an operation as that performed through a standard incision.
Minimally invasive surgery has many benefits compared to traditional surgery:
- Lower hospital risk
- Smaller incision - smaller scar (2 to 4 inches instead of the 6 to 8 inches required for traditional valve surgery)
- Shorter hospital stay - in many cases, only 3 to 5 days are needed (instead of the average 5 to 7 days for traditional surgery)
- Shorter recovery time after discharge
- Less bleeding
- Less potential for infection
- Less pain and trauma
Future innovations will include smaller ports (incisions) and use of video and robotics to move toward a completely endoscopic approach. In addition, advances in percutaneous, non-surgical approaches may lead us toward even less invasive heart valve repair and replacement.
Photo of Cosgrove-Edwards Annuloplasty band with permission from Edwards Lifesciences
In the early 1990s, Dr. Cosgrove, Department Chairman of Cardiovascular and Thoracic Surgery at the Cleveland Clinic Heart Center, developed an annuloplasty system, designed to help support the valve annulus, while maintaining the normal shape and function of the valve.
Valve repair
Valve repair is now the method of choice for surgical treatment of mitral valve disease thanks to improvements in techniques over the past 20 years. Through valve repair, the natural anatomy of the heart valve is maintained.
The surgeon repairs the tissue of the damaged valve and usually implants an annuloplasty ring to provide extra support to the valve.
For mitral and tricuspid valve disease, the surgeon is able to:
- Repair prolapsing (floppy) leaflets
- Open fused leaflets
- Remove calcium deposits
- Support and tighten an enlarged annulus by attaching a ring or band
Bicuspid aortic valve disease (two leaflets instead of three) is a very common type of aortic valve disease. When there is a leak, the surgeon may be able to reshape the aortic valve leaflets, allowing the valve to open and close more easily.
Click here for information, illustrations and videos regarding mitral valve repair
Valve replacement
When valve repair is not possible, replacement of the diseased valve with a new heart valve is performed. Although valve replacement surgery has been performed since the 1950s, refined techniques and materials have improved the outcomes and options. Sapirstein and Smith 1 state there are qualities which would define the "ideal valve:"
- The valve functions like the patient's own normal heart valve
- The valve permits normal forward flow and prevents any backflow when closed
- The opening and closing of the valve is synchronized with the normal heart cycle
- Flow through the valve is smooth and the material the valve is made of does not promote clotting
- The valve is easy to implant so that all surgeons have the same results
- After valve surgery, the patient does not have to make any changes in lifestyle (take medications, not be at risk for infection, not hear the new valve)
- The valve should be durable
Although there may be no valves today that precisely meet each of the criteria, current valves are coming closer to this ideal.
There are two options for replacing a heart valve: mechanical valves and tissue (bioprosthetic) valves.
Mechanical valves:
Mechanical valves are made totally of mechanical parts that are tolerated well by the body. The bileaflet valve (pictured below) is used most often. It consists of two carbon leaflets in a ring covered with polyester knit fabric. Mechanical heart valves are made in many sizes to fit any size heart, from large to very small.
St. Jude Medical® Mechanical Heart Valves
Photographs posted with permission from St. Jude Medical®
St. Jude Medical® Mechanical Heart Valve
SJM Regent® Valve
The St. Jude Medical® Regent valve is available for aortic valve replacements, and the standard St. Jude Medical® is used in the mitral or aortic valve positions.
The St. Jude heart valve was the first bileaflet mechanical heart valve (St. Jude Medical® (SJM)). This valve has a track record spanning 3 decades of excellent results. This bileaflet mechanical heart valve is designed and manufactured of pyrolytic carbon.
The Carbomedics Prosthetic Heart Valve (CPHV™)
Photographs posted with permission from CarboMedics
Top Hat™ Supra-Annular Aortic Valve
Standard Mitral Valve
Carbomedics manufactures a variety of bileaflet mechanical heart valves. The Top Hat Supra-Annular valve is used for aortic valve replacement and the standard valve in the mitral position. A third valve, the Reduce R Aortic Valve may also be used for aortic valve replacement.
The valve housing and leaflets are made of Pyrolite carbon, a unique form of carbon which Carbomedics engineers discovered in the sixties. Attached to the carbon housing is a reinforcing band of titanium and attached to the titanium band is a suture ring of PET fabric. A metallic nitinol wire holds the titanium ring to the housing with an interference groove system. Pyrolite is biocompatible.
There are advantages and drawbacks to mechanical valves.
Advantages: Mechanical valves are very durable. They are designed to last a lifetime.
Disadvantages: Due to the artificial material involved, patients who receive these valves require lifelong treatment with a blood-thinning (anticoagulant) medication. Blood-thinners are medications (such as warfarin or Coumadin) that delay the clotting action of the blood. They help prevent clots from forming on the mechanical valve, which can cause a heart attack or stroke.
Tissue valves (also called biologic or bioprosthetic valves):
Tissue valves (also called biologic or bioprosthetic valves) are made of human or animal tissue. They may have some artificial parts to help give the valve support and to aid placement. There are three types of tissue valves: pig tissue (porcine), cow tissue (bovine), and human (allografts or homografts).
Porcine stented valve - Information and photographs posted with permission from Edwards Lifesciences®
The porcine stented valve was the first generation of porcine tissue valves. They have been available for more than 30 years.
The valves are made from natural porcine aortic valves, but may be used for aortic or mitral valve replacement. They are trimmed and then fixed in buffered glutaraldehyde at high pressure. The valves are mounted on flexible stents (frames). The bottom of the valve is covered with a seamless knitted polytetrafluoroethylene cloth. This material helps to facilitate the healing and ingrowth of tissue around the implanted valve.
Porcine stentless valve - Information and photographs posted with permission from Edwards Lifesciences®
The porcine stentless valve is used for aortic valve replacement. The valve is made from a natural porcine aortic valve and is fixed in buffered glutaraldehyde solution at a low pressure.
No stents or synthetic sewing rings are used. Therefore, these valves are very similar to the homograft valve (see below).
These valves are technically more difficult to implant but are useful in patients with small hypertrophied hearts.
The Carpentier-Edwards PERIMOUNT Pericardial Bioprosthesis - Information and photographs posted with permission from Edwards Lifesciences®
Valves built to last
This valve is made of bovine pericardial tissue (tissue from a cow heart) that has been preserved in a buffered glutaraldehyde solution and mounted on a flexible frame and a sewing ring of molded silicone rubber, which allows the surgeon to sew the valve to the patient. Both the frame and the sewing ring are covered with a knitted polytetrafluoroethylene (PTFE) cloth.
The aortic pericardial bioprosthesis has been implanted internationally since 1981, and in the United States since 1991. In the summer of 2000, Carpentier-Edwards released a PERIMOUNT valve for the mitral position.
The benefit of this valve is enhanced durability, which is related to the use of pericardium and the specific bioengineering involved in the valve design. Click here to learn more about the durability of these valves.
Aortic Valve Allograft - the Homograft Valve
A homograft (also called allograft) is a valve that has been removed from a donated human heart, preserved and frozen under sterile conditions.
Homografts are ideal valves for aortic valve replacement, especially when the aortic root is diseased or there is infection. The heart's natural anatomy is preserved and patients do not need to be on any blood-thinner medications. Although the limited availability is a drawback in some settings, we maintain a large supply.
Information and photographs posted with permission from CryoLife®, Inc.
Ross Procedure
The Ross procedure involves switching your pulmonary valve to the aortic valve position and then placing a pulmonary homograft. This is a very complex procedure; however it has many benefits, especially for young patients with aortic valve disease. Techniques, such as the Ross Procedure are examples of innovative ways surgeons are able to treat valve disease while protecting the heart's natural functioning. Click here to learn more.
There are advantages and drawbacks to biologic valves.
Advantages: Most patients do not need to be on lifelong blood-thinner medication, unless they have other conditions (such as atrial fibrillation) which warrant it.
Drawbacks: Biologic valves, traditionally, were not considered as durable as mechanical valves, especially in younger people. Previously available biologic valves usually needed to be replaced after about 10 years. However , recent studies on the PERIMOUNT aortic valve, show that these valves may last at least 17 years without decline in function. This represents a new milestone in durability of biologic valves.
Atrial fibrillation
Atrial fibrillation is the most common cause of an irregular heart beat. Cleveland Clinic Foundation Heart Center surgeons can now eliminate this abnormal rhythm in patients with atrial fibrillation who require valve surgery. Click here to learn more about surgical treatments for atrial fibrillation.
Valve surgery today at the Cleveland Clinic Foundation offers patients state of the art, minimally invasive treatment options with excellent long-term results. Your surgeon and cardiologist use many variables (your age, lifestyle, medical condition, heart anatomy and diagnostic test results) to decide what is the best treatment for you. Click here to learn more about valve disease, symptoms, diagnosis and treatment .
Click on the links below to find a Cleveland Clinic cardiovascular surgeon who performs valve surgery
Click here to learn more about heart valve surgery from the Cleveland Clinic Heart and Vascular Institute
Learn more about heart surgery topics
To obtain a surgical consultation, or if you have additional questions or need more information, you may contact us by :
- Email, using the Contact Us Form.
- Call the Heart & Vascular Institute Resource Nurse at 216/445-9288 or toll-free 866/289-6911.
Webmail and phone calls are answered between 8:30 am to 4:00 pm on regular business days.
Resources:
- Sapirstein JS, Smith PK. The "ideal" replacement heart valve. American Heart J 2001; 141:856-860.
- Gillinov AM. Chordal transfer for repair of anterior leaflet prolapse. Multimedia Manual of Cardiothoracic Surg, 2005.
- Gillinov AM, Garcia MJ. When is concomitant aortic valve replacement indicated in patients with mild-moderate stenosis undergoing coronary revascularization? Curr Cardiol Reports, 2005;7(2):101-4.
- Gillinov AM, Cosgrove DM. Percutaneous heart valve repair and replacement. Endovascular Today, 2004;3:31-4.
- Gillinov AM, Cosgrove DM. Cosgrove ring annuloplasty for functional tricuspid regurgitation. Op Techni Thorac Cardiovasc Surg, 2003;8:184-7.
- Gillinov AM, Cosgrove DM. Current status of mitral valve repair. Am Heart Hosp J, 2003;1:47-54.
- Gillinov AM, Faber CN, Houghtaling PL, Blackstone EH, Lam BK, Diaz R, Lytle BW, et al. Repair versus replacement for degenerative mitral valve disease with coexisting ischemic heart disease. J Thorac Cardiovasc Surg, 2003;125:1350-62.
- Gillinov AM, Banbury MK, Cosgrove DM. Hemisternotomy approach for aortic and mitral valve surgery. J Card Surg, 2000;15:15-20.
- Gillinov AM, Banbury MK, Cosgrove DM. Is minimally invasive heart valve surgery a paradigm for the future? Curr Cardiol Rep, 1999;1:318-22. Review.
- Banbury MK, Cosgrove DM 3rd, Thomas JD, Blackstone EH, Rajeswaran J, Okies JE, Frater RM. Hemodynamic stability during 17 years of the Carpentier-Edwards aortic pericardial bioprosthesis. Ann Thorac Surg. 2002 May;73(5):1460-5
- Gillinov AM, Cosgrove DM, Blackstone EH, Diaz R, Arnold JH, Lytle BW, Smedira NG, Sabik JF, McCarthy PM, Loop FD. Durability of mitral valve repair for degenerative disease. J Thorac Cardiovasc Surg 1998;116:734-43.
- World View Through 8 Centimeters: An International Tele-Symposium on Minimally Invasive Direct Access Valve Surgery, Edwards CVS Division and the Cleveland Clinic Foundation, 1997
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http://www.edwards.com*
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http://www.carbomedics.com/patients_links.asp
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http://www.cryolife.com*
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http://www.sjm.com*
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