Every year about 200,000 patients in the United States need a new heart valve because they have severe aortic stenosis. This is a condition in which the aortic valve starts to narrow and affect the efficient flow of blood from the heart to the other parts of the body. This can lead to congestive heart failure and sudden death.
Open-heart surgery is a very common procedure for such heart patients. However for some who are too old, too sick or may have had chest surgery before, this is not the option.
A less invasive procedure is now available for these patients. The doctor has to mount a valve on a catheter and then insert it into the patient’s groin or chest and thread it towards the heart.
This technique does not require stopping the heart and placing the patient on a heart-lung bypass machine, so weaker or sicker patients can endure the procedure. Without valve replacement, the life expectancy of patients with severe aortic stenosis is typically less than five years.
This two-hour procedure to replace the damaged aortic valve with a ‘stent-supported valve’ was pioneered in France in 2002. In February 2009, Singapore became the first country in Asia to perform it.
Since then, five elderly patients have undergone this procedure at the Singapore General Hospital’s National Heart Centre. This treatment is recommended only to patients who have no other options or who are suffering from narrowed-valve symptoms like chest pain and breathlessness.
This procedure is still relatively new and how long the valve will last and the long term effects are still unknown. Comparatively the synthetic valves used in conventional open-heart surgery lasts 10 to 20 years. For this reason, the hospital is not promoting the procedure to younger patients and those who are eligible for standard surgery.
There are also risk factors and a patient undergoing such procedure can die from a punctured blood vessel.
The success rates for this transcatheter technique in USA and Europe have been reported to be 90%.
The conventional valve costs about US$3000 while the new valve is almost 10 times more, though this is expected to be reduced in time.
With an aging population, the heart centres in Singapore are expected to treat an increasing number of patients with valve problems.