Growing evidence supports the use of transcatheter aortic valve implantation (TAVI) for patients with severe, symptomatic aortic stenosis in the intermediate risk category in the intermediate risk category, says Edwards Lifesciences.
Findings from the PARTNER II randomised trial published in the New England Journal of Medicine showed that TAVI, using the Edwards SAPIEN 3 valve, has outcomes similar to surgery and even superior with transfemoral access in the intermediate-risk patient population.
Additionally, a clinical practice guideline based on three systematic reviews was published in the British Medical Journal and recommended TAVI for patients at low to intermediate surgical risk.
There are two methods to replace the calcified aortic valve with an artificial valve: TAVI, and surgical aortic valve replacement (SAVR). Without treatment, half of patients die within two years of experiencing symptoms.
Traditionally, conventional SAVR has required making an opening in the chest under anaesthetic. The defective valve is then replaced with an artificial heart valve in open-heart surgery. During the operation, the patient's heart is connected to a heart-lung machine. This procedure can last a few hours. This is a successful method which has been used by surgeons since the 1960s, however, as a result of age and other health factors, it is not suitable for up to 30% of patients.
TAVI is a minimally invasive method primarily used when the patient is at high or intermediate risk for surgery. The artificial heart valve can be squeezed tightly so that it can pass through a catheter usually through a small incision in the groin up to the heart. It can then be placed in the beating heart via various entry points in the body, before it is unfolded in the location of the original heart valve by means of balloon inflation of self-expansion. The heart valve is usually put in place in under an hour. It is not necessary to open the chest and stop the heart and lungs, so the heart can continue to beat during surgery.
TAVI can be implanted, often under conscious sedation, in less than an hour and is associated with a much quicker recovery and shorter lengths of stay in hospital. With TAVI, patients often leave hospital in less than a week and are enjoying a good quality of life rapidly, whereas surgical patients often remain in hospital for 2-3 weeks and take 3-6 months to fully recover.
Heart valve disease
Heart valve disease is a growing health concern. Approximately 1.5 million people over the age of 65 are currently affected by the condition in the UK, and this figure is expected to rise to 3.3 million by
2056, representing a 122% increase. The chances of developing the condition increase with age; estimates suggest that by the age of 75, the prevalence of heart valve disease is over 13%. With nearly 25% of people in the European Union expected to be over 65 by 2030, the prevalence of heart valve disease is also set to increase. Studies also show that outcomes for patients who aren't treated are significantly worse than for those that have undergone heart valve replacements.
Aortic stenosis is the most common form of heart valve disease, affecting 2-7% of the population over 65. It is the narrowing of the aortic valve opening, which limits the amount of blood flow from the left ventricle to the aorta. It is most-often due to age-related degeneration and is characterised by calcification - on the valve leaflets. This decreases the flexibility of the leaflets and impairs their opening and closing motion, obstructing the flow of oxygen-rich blood to the body.