New Frontiers in Heart Valve Procedures: Percutaneous Valve Repair
For several decades now, the percutaneous treatment of coronary artery disease in modern cardiovascular care has become an important therapeutic strategy, especially in acute diseases. These procedures are carried out in catheterization suites equipped with instrumentation for radiological visualization of the instruments used and for the necessary angiographic evaluation. More recently, these techniques have been progressively extended to the treatment of congenital heart disease and valvular disease of the adult.
Treating aortic stenosis
Aortic stenosis affects an increasing proportion of patients with age: it represents, in fact, calcific degeneration of the aortic valve, which becomes more prevalent from the seventh decade of life. To date, more than 150,000 transcatheter aortic valve prostheses have been implanted worldwide. The era of percutaneous treatment of valvular disease has well begun, in effect representing a real therapeutic option. While traditional heart surgery employing cardiopulmonary bypass still represents the standard of care, these innovative percutaneous techniques are applicable in many patients who cannot undergo standard surgical interventions or have an unacceptable surgical risk.
The symptoms of aortic stenosis — breathlessness, chest pain or sudden loss of consciousness — tend to deteriorate rapidly over time. Drug therapy may partially improve the patient’s condition, but cannot stop the progressive obstruction of ejection of blood from the heart into the circulatory system. Until a few years ago, about 30 percent of patients remained entirely excluded from surgical intervention because they were judged completely inoperable or because they were deemed to have an extreme operative risk. These are patients suffering from serious diseases of other organs such as the lungs or liver, or very old patients judged too fragile to deal with traditional surgery. Today, for these patients it is sometimes possible to receive a new valve without open heart surgery. The prosthetic valve is, in fact, properly positioned in the heart through accessing the femoral artery in the groin, or through a small incision on the side wall of the chest and direct access of the heart (trans-apical approach). An additional alternative access is the transaortic approach, performed through a small incision in the chest or via the subclavian or carotid artery.
Treating mitral valve disease
Innovative techniques have also been developed for the treatment of mitral valve disease. Now, it is also possible to repair mitral valve regurgitation and improve the symptoms in patients with high surgical risk. Currently, the only device approved by the FDA for treatment of mitral valve regurgitation is the MitraClip (Abbott, Menlo Park, CA): it consists of a “clip” fixed on the leaflets of the mitral valve. The clip reduces the degree of valvular regurgitation, mimicking what has been performed by a cardiac surgeon’s hand — the so-called “Alfieri stitch.”
Careful assessment is needed in order to properly select patients who are optimal candidates. The implant procedure is performed from the femoral vein approach, with a large caliber catheter that allows the operator to reach the heart with the device. Performed through a small opening in the atrial septum, the operator is able to access the left atrium and the mitral valve structures. MitraClip is a safe procedure, in which there is a low incidence of complications. A further advantage of echocardiographic monitoring is the ability to immediately verify the effectiveness of the intervention before completion, as the MitraClip is completely repositionable and removable, in the event of an unsatisfactory result.
Studies are underway now to test the safety and efficacy of the complete replacement of the diseased mitral valve using a trans-apical transcatheter approach.
The ability to repair or replace valves without the need for traditional open heart surgery is a fascinating prospect which is still evolving. The patients who benefit most are those who are frail and can’t undergo traditional open heart surgery. In this sense, the percutaneous interventions and traditional heart surgery are not considered competitive, but complement each other to offer each patient the best prospect of healing and life.
For more information
The UW Health Heart Valve Clinic provides a multidisciplinary approach to diagnosing and treating heart valve disease. Our team of physicians, including cardiologists, cardiac surgeons, imaging specialists and anesthesiologists, work together to offer treatments that suit each patient’s specific type of valve disease.