Transcatheter Aortic Valve Replacement
Stenosis (narrowing) and calcification of the aortic valve of the heart poses a threat to the lives of many patients. In the last decade, it has been widely used new, safe and effective minimally invasive technique of aortic valve replacement using a catheter.
Calcification and stenosis of the aortic valve is often found in patients older than 75 years. In the event of a significant narrowing of the valve, surgery is required to replace it. In the past, the only technique of such a procedure was open-heart surgery. In recent years, a more efficient and safer method for the patient became available - aortic valve replacement through a minimally invasive catheterization.
The aortic valve is located between the left ventricle and the aorta, carrying an important hemodynamic function. During contraction of the left ventricle blood flows through the valve into the aorta and hence into all organs and tissues of the human body. With age, calcium deposits (calcification) on the flaps of the valve result in a narrowing of the lumen of the valve ring. In the early stages of this process symptomatic drug treatment may be applied, however, these drugs do not prevent disease progression. Narrowing the diameter of the valve up to one centimeter or less limits blood flow to the rest of the body. In addition, stenosis also places a severe overload on the heart, heart failure and a high risk of irreversible complications. The only solution to this problem is the replacement of the aortic valve.
Aortic Valve Replacement and High Risk Patients
Until recently, aortic valve replacement was performed exclusively during open-heart surgery - a complex surgical procedure requiring thoracotomy (opening the chest) and long-term post-operative rehabilitation. At the same time, about a third of patients with critical narrowing of the aortic valve are at high risk of complications due to having previously undergone surgical intervention on the chest or severe comorbidities. Conducting open-heart surgery in these patients is often impossible.
The Minimally Invasive Approach of Catheterization
Modern technologies allow for the safe replacement of the aortic valve in patients belonging to the group of high risk. Advantages of catheterization lies in the fact that there is no need for opening the chest and general anesthesia (light sedation and local anesthesia). During the procedure, access to the aortic valve is via an artery in the groin. Numerous studies have shown high efficiency of this method that restores the heart's activity, and leads to significant improvements in cognitive function in elderly patients. In addition, it is proved that complications during and post-surgery are significantly lower in minimally invasive catheterization than with traditional open-heart surgery.
Advanced Valve Replacement at HMC
Leading Israeli heart surgeon at Herzliya Medical Center - Professor Ran Kornowski adds, "A breakthrough in the practice of minimally invasive aortic valve replacement techniques is the use of modern implants, such as the artificial valve EVOLUT R. This valve is designed so that it is inserted through the thin arterial catheter in a folded state and then opens at the site of implantation." An additional advantage of the implant EVOLUT R is its small diameter, only 4.5 mm, which allows the passage of the catheter through the narrowed vessels.
The artificial valve EVOLUT R is a metal frame, to which are attached flaps made from biological materials. After straightening, at the site of implantation artificial valve expands narrowing of the valve ring. Application EVOLUT R is FDA approved, as well by the ministries of health in Europe and Israel. After a few days and following the procedure, the patient can undergo rehabilitation and return to normal daily activity.
At present, Israel has performed more than 500 surgeries annually to replace the aortic valve using advanced minimally invasive techniques, a large proportion of which is done at Herzliya Medical Center. Prof. Kornowski emphasizes: "The use of a new generation of artificial aortic valve can significantly extend the indications for such procedures, including patients suffering from severe chronic illnesses, for which open-heart surgery is extremely dangerous or impossible."