Transcatheter Aortic Valve Replacement (TAVR)
Severe aortic stenosis is common in people over 65 years old. There are 2 major causes of the condition including bicuspid aortic valve and degenerative aortic valve. The calcium builds up and aortic tissues causes thick and stiff aortic valve so that the valve opening becomes narrow, obstructing the lower left heart chamber to pump blood to other organs. Patients can experience fatigue after activity, chest tightness and pain, fainting, or even heart attack. 50% of the patients have a risk of sudden cardiac death within 2-5 years.
Image 1: Normal aortic valve |
Image 2: Narrowed aortic valve |
Due to the seriousness of the condition, patients should receive a treatment before the progression or sudden cardiac death.
Treatment
The conventional treatment for severe aortic stenosis is an open-heart surgery to replace the aortic valve. This is effective in patients with low risks and the mortality rate is 1-2%.
However, this treatment modality is not suitable to some patients such as patients with old age and multiple preexisting medical conditions or those who had an open-heart surgery in the past because their physical condition is frail. The mortality rate from the surgery can be higher than 20%. Due to the operative risks, some patients are rejected from this conventional treatment and eventually led to death. This group of patients do not have a medical opportunity for longevity and quality of life.
Image 3 and 4: Aortic valve implant and devices used for Transcatheter Aortic Valve Replacement
Transcatheter Aortic Valve Replacement (TAVR) is the medical innovation for severe aortic stenosis in particular. According to long-term clinical studies, TAVR becomes the internationally accepted standard treatment method with statistical data of lowered mortality rate, shorter hospital stay, faster recovery, decreased hospital readmission, and improved patient’s quality of life.
The procedure of TAVR is cardiac catheterization of bioprosthetic heart valve to replace the native aortic valve via artery. The artificial valve will be attached to a collapsed or compressed stent inside a catheter of 8-10 mm diameter. The catheter will be threaded and guided through transfemoral, trans subclavian or trans axillary, direct aortic, or tans apical route, depending on the doctor’s discretion. The replacement valve will be advanced to the old aortic valve, with the use of X-ray imaging to visualize and locate the site.
Image 5: X-ray image of transcatheter artificial aortic valve
After the artificial heart valve is in place, it can immediately function. With this method, patients have only a small incision where a catheter is inserted, minimal bleeding, speedy wound healing, and faster recovery. Patients can return home within 2-3 days if there are no complications.