Structural Heart Programme: Aortic Stenosis & TAVI
Structure & function of the heart
Our heart consists of four chambers. There are two upper chambers called the left and right atrium, and two lower chambers called the left and right ventricles. Each chamber of the heart has one valve, making it 4 valves in total. The valves allow the blood to move through the heart in a single direction only.
The valves are called the aortic valve, pulmonary valve, tricuspid valve and mitral valve.
The mitral valve and tricuspid valve are located between the atria and the ventricles.
The aortic valve and pulmonary valve are located between the ventricles and the major blood vessels leaving the heart.
Types of heart valve disease
When heart valves become diseased or damaged, they may not completely open or close. Your heart will find it hard to pump properly. As a result, your heart will pump even harder to make sure there is enough blood circulating around your body. As the heart muscles become overworked, other heart problems follow.
Stenosis and regurgitation are the two types of heart valve diseases. Some people may even have a combination of both.
Stenosis occurs when your valve does not open properly. The heart becomes strained as the pressure and blood can back up.
Regurgitation, also known as an insufficiency, occurs when your valve does not close properly. Blood leaks through the valve rather than flows in one direction only. Also, the heart is forced to work harder to maintain enough blood circulating around your body.
What is Aortic Stenosis (AS)?
Valves in the heart act like windows to ensure blood flows from one chamber/structure to the next in a single direction.
Aortic stenosis is a disease described by the narrowing of the valve opening due to congenital abnormality, age-related degeneration and rheumatic valve disease. This will interrupt the ability of the heart to pump blood out to supply the body. Over time, the heart function will progressively weaken.
Patients with moderate to severe AS may not show any symptoms at all. However, in the late stages, patients may complain of chest pain (angina), shortness of breath (dyspnea) and even fainting spells (syncope). These symptoms are made worse with physical activity.
What are the causes of aortic stenosis?
Several conditions can cause your aortic valve to thicken. Among them are:
What are the aortic stenosis symptoms?
When you have mild aortic stenosis, you may never feel any symptoms. For serious cases, there are some symptoms worth noting. They include:
Transcatheter Aortic Valve Implantation (TAVI)
What is TAVI ?
TAVI, an acronym for Transcatheter Aortic Valve Implantation (or Replacement, TAVR), is a minimally invasive procedure to replace the diseased aortic valve as opposed to conventional heart surgery.
With advancements in device technology, non-invasive imaging, increasing operator expertise and proper patient selection, the outcome of TAVI may be comparable but with less morbidity, shorter hospital stays and resumption of normal activities in a much shorter time.
How does TAVI Work?
The prosthetic aortic valve is mounted within a special catheter. This catheter is carefully advanced from the groin or shoulder artery and delivered across the diseased valve. The procedure is performed under the guidance of x-ray imaging and transesophageal echocardiography.
Once the valve is optimally positioned, it will be deployed. This new valve will immediately take over the function of the diseased valve.
This TAVI procedure may be conducted under general anaesthesia or conscious sedation.
Benefits of TAVI
- A shorter length of stay in ICU and hospital
- Faster or almost no need for wound recovery
- Less bleeding
- Earlier ambulation and return to a normal quality of life
Complication of TAVI
- Electrical Conduction abnormalities that may require permanent pacemaker implantation
- Perivalvular Leak
- Obstruction of the coronary arteries
- Possible complications related to the Vascular Access site
Mitral Valve Regurgitation
What's mitral valve regurgitation?
Mitral regurgitation is backward blood leakage through the mitral valve each time the left ventricle contracts.
A leaking mitral valve causes blood to flow in two directions during the contraction. Some blood flows through the aortic valve (as it should normally) and some blood flows back into the atrium.