Transcatheter aortic valve replacement (TAVR) or transcatheter aortic valve implantation (TAVI) is a minimally invasive procedure whereby a new valve is inserted without removing the old, diseased valve to treat severe aortic valve disease called aortic stenosis (AS). The procedure was initially developed for very high-risk patients who could not withstand major surgery, but in recent years has been extended to treat other suitable lower-risk patients as well.
Bioprosthetic aortic valves made from pig or cow heart tissue used in TAVR
Fluoroscopic X-ray image of bioprosthetic aortic valve implantation deployment showing expanded metal mesh scaffolding which keeps the valve in place
Icono Angiography System
Aortic stenosis is a heart valve disease in which the valve is thickened, calcified, and becomes stiff and narrow so it cannot fully open during the ejection phase of heart contraction. Typical symptoms of aortic stenosis, particularly in severe cases, are shortness of breath, chest pain, fainting and fatigue. The essence of this treatment is to replace the diseased aortic valve with a new one through an intravascular approach, obviating the need for conventional major open-heart surgery—surgical aortic valve replacement (SAVR). Several recent studies show that TAVR is safer, less risky, and has either similar or even better functional outcomes than those of SAVR.
From left: Demonstrates normal, fully opened aortic valve; Demonstrates aortic stenosis (AS)
TAVR can be an alternative option for patients who are at high risk of complications or may not be able to tolerate open-heart surgery and cardiopulmonary bypass, a major operation. Hence, TAVR leads to a shorter hospital stay compared to SAVR.
The decision to treat severe aortic stenosis with TAVR will be made after deliberation by a team of interventional cardiologists and cardiothoracic surgeons to determine the best and safest treatment approach for each patient.
Recommendation for TAVR
- Severe aortic stenosis with or without concomitant medical conditions such as lung or kidney disease makes open-heart valve replacement surgery too risky.
- Biologic tissue aortic valve failure in patients who had previous surgical aortic valve replacement.
Bioprosthetic aortic valves made from pig or cow heart tissue used in TAVR
Clinical data needed for TAVR planning
- Electrocardiogram (ECG), chest X-ray, comprehensive 2D-echocardiogram
- Blood tests
- Coronary angiography (CAG) data
- Computed tomography angiography (CTA) of whole aorta
Fluoroscopic X-ray image of bioprosthetic aortic valve implantation deployment showing expanded metal mesh scaffolding which keeps the valve in place
Potential risks of TAVR
- Access site bleeding, bruising, pain, or damage to access blood vessel
- Problems with the replacement valve, such as dislocated or leaky valve
- Embolic stroke
- Heart rhythm abnormalities particularly slow heart rate requiring a permanent pacemaker
- Temporary or long-term kidney injury
- Heart attack during or after the procedure
- Infection
- Death
However, studies show that the risks of disabling stroke and death are similar among those who have TAVR and SAVR.
TAVR procedure
TAVR is conducted in a hybrid operating room equipped with a sophisticated angiography unit. Under sedation or general anaesthesia, a catheter (a thin, long flexible tube) is inserted into an artery, usually in the groin or upper chest area, and threaded to reach the site of the aortic valve at the root of the aorta, guided by real-time fluoroscopic X-ray images and an echocardiogram.
The bioprosthetic valve-loaded catheter, once correctly positioned, is deployed within the existing aortic valve, again under X-ray and echocardiographic guidance. The bioprosthetic valve can either be balloon-inflatable or self-expandable depending on the deployment mechanism of the valve platform. The newly expanded valve flattens the old valve leaflets against the wall of the aorta and takes over the normal function of the aortic valve in maintaining unidirectional blood flow.
During the procedure, the patient will be closely monitored for all essential physiologic parameters by a specialised team of healthcare professionals, including the anesthesiologist.
After the procedure, the patient will be observed and monitored overnight in an intensive care unit (ICU), before moving to a regular ward the next day. Typically, patients will spend 3-5 days in the hospital. TAVR has faster recovery as compared to SAVR; patients ordinarily can resume normal daily activities in just a few days, while with SAVR, full recovery may take a few months.
Heart disease is an extremely life-threatening medical condition if left untreated. In-depth knowledge of one’s condition and finding the right treatment by a trusted and experienced physician can make a big difference to the treatment outcome and the patient’s quality of life. Do not wait until it’s too late before taking action.
Author: Dr Piyanart Preeyanont (M.D) Cardiologist, Cardiology Center, MedPark Hospital.
Series Editor: Katalya Bruton, Healthcare Content Editor and Director, Dataconsult Ltd. Dataconsult’s Thailand Regional Forum provides seminars and extensive documentation to update business on future trends in Thailand and in the Mekong Region.
