Surgery is recommended for patients with severe aortic stenosis and who have developed the symptoms described above.
“A normal valve opens to about three to four square centimetres. When the valve cannot open more than one square centimetre, or even less, this is considered severe,” Assoc Prof Ho said.
He added that another factor doctors look at is the speed of red blood cell flow across the heart valve – a tighter heart valve increases the speed that blood cells travel.
This conservative approach to surgery is because of its considerable risks, especially for elderly patients with multiple medical conditions, Assoc Prof Ho said.
“We need to time these procedures carefully in order for patients to benefit from it without being too late in treatment,” he said.
SURGERY AND RECOVERY FROM AORTIC STENOSIS
Traditionally, open heart surgery with surgical valve replacement was the primary treatment option for aortic stenosis. In this procedure, doctors make an incision in the chest to access the heart, identify the narrowed valve, remove it and replace it with either a metallic or biological valve.
However, since 2009, a minimally invasive procedure, the Transcatheter Aortic Valve Implantation (TAVI) has been available in Singapore. NHCS treats about 100 patients with this procedure each year, said Assoc Prof Ho.
TAVI involves a small puncture, typically to the leg or groin area. A catheter is inserted through the artery and guided to the heart, where a replacement biological valve (usually made of animal tissue) within a metal stent is positioned within the narrowed valve.
The new valve expands and pushes the old, narrowed valve to the side, taking over its function to allow for improved blood flow from the heart to the rest of the body.