By Ng Wan Ching

HE was born with a hole in his heart and a narrowing of his aorta.

Surgeons had operated twice on Mr Zhong Yang De, 23, a civil servant, when he was an infant.

Once, to close the hole in the heart, and another time, to widen the narrowed part of the aorta.

But when Mr Zhong grew up, the part of the aorta that was widened surgically had narrowed significantly again.

Scans showed that the re-narrowed part of his aorta was about half the size of a normal aorta.

(The aorta is the body's largest artery that carries blood away from the heart.)

It was a cause of concern for his doctor as this condition would lead to high blood pressure and unduly overwork Mr Zhong's heart.

Said Associate Professor Quek Swee Chye, head and senior consultant at the National University Hospital's (NUH) University Children's Medical Institute: 'Previously, the treatment for re-narrowing was surgery. But this would be difficult because of the previous surgery that Mr Zhong has had.'

The area would have scar tissues and the operation would be a major one, needing many days of recuperation.

Fortunately for Mr Zhong, it is now possible to expand this narrowed segment of the aorta using a stent. (See graphics)

The stent used for this procedure can be expanded to become several times wider than the traditional coronary stents used to open up blocked heart vessels.

A coronary stent is usually about 3mm wide.

'We performed this procedure last October on Mr Zhong,' said Associate Prof Quek.

He believes this is the first time that a re-narrowing of the aorta is treated non-surgically in Singapore.

A check with the National Heart Centre (NHC) showed that it had not carried out such a procedure before.

Stenting the aorta

Mr Zhong had the procedure done while under general anaesthesia.

The procedure is carried out through an insertion of the stent via a catheter entering the patient's groin.

It is threaded all the way to the narrowed part of the aorta.

The stent is then balloon-dilated to open up the narrowed segment.

After that, the catheter and balloon are removed, and there is no residual scar.

The entire procedure took about two hours.

'The results achieved are excellent, with immediate reduction in the blood pressure,' said Associate Prof Quek.

Compared to surgery, where the average length of stay in hospital is about a week, the patient can be discharged the next day.

Mr Zhong stayed in hospital for two days after his procedure because Associate Prof Quek wanted to observe him.

'There is a risk of rupture of the aorta after such an operation,' he said.

Mr Zhong has to be monitored every six months. The cost of the stent and the procedure is $4,800, excluding hospital stay.

The best part for Mr Zhong is that there was very little pain and no surgical scar associated with this technique.

He said: 'I felt pain for only one day after the procedure and there is no scar, only a small hole in my groin area where they inserted the catheter.'

About one out of every 100 children born in Singapore each year would have congenital heart disease, said Associate Prof Quek.

Of these, 5 per cent may have a narrowing of the aorta.

Depending on the severity of the condition, not all of them would need surgery.

This condition not only results in hypertension and pressure loading of the heart, it may also lead to inadequate blood supply to the lower limbs and abdominal organs in serious cases.

It can now be detected shortly after birth, and surgery to open up the narrowed portion of this vessel is done, said Associate Prof Quek.

However, one of the well-recognised problems following surgery is that the area of narrowing tends to get re-narrowed as the child grows, a condition known as re-coarctation or re-narrowing.

This is because the segment that is originally narrowed may be abnormal and the fibrous tissue surrounding it limits further growth as the rest of the vessel enlarges with age.

Said Mr Zhong: 'Even though I have learnt how to take care of my health from a young age, that part of my aorta had narrowed again. The doctor said if I didn't do anything about it, it would narrow even further and affect my health.'

He continues to take care of his health by exercising moderately, and refraining from drinking and smoking.

'I feel better after the procedure and even though I still cannot exercise too vigorously, it's a small price to pay,' said Mr Zhong.

This story was first published in The New Paper on Sept 9, 2008.