Andy Smith became a French film star of sorts last night - at least his heart did.

Cardiologists working on him at Auckland City Hospital demonstrated a new technique, through a live video link, to an audience of 3000 to 4000 at a Paris convention of heart specialists.

"It's quite an honour," said Mr Smith, 48, a Palmerston North plumber, before the procedure, nicknamed "kissing balloons".

He was diagnosed with angina this year after suffering what he first thought was indigestion, followed by worsening chest pain.

Angina is usually caused by heart arteries being narrowed by fatty deposits, restricting the flow of oxygen-rich blood to the heart muscle.

Mr Smith was awake during the angioplasty procedure, done under local anaesthetic through a narrow remote-control tube inserted through an artery in his groin.

He was sent to Auckland since he was considered a good candidate for showing the new technique, because of the nature of his heart problem.

In the procedure, two little mesh metal "stents" are inserted into the narrowed heart arteries to restore full blood-flow.

The stents, left in place, are expanded using tiny balloons which are then withdrawn. They are also coated in a medicine that inhibits the growth of healing tissue, which can cause the arteries to narrow again.

Mr Smith's cardiologist, Dr John Ormiston, demonstrated to the world's largest cardiology convention a special way of using stents to treat a complicated branching of a coronary artery.

The technique is used on patients with narrowed branches of the major heart arteries. It is called kissing balloons because it uses two balloons side by side.

"We are arrogantly recommending kissing to a French audience," Dr Ormiston quipped.

He said his team had proven the effectiveness of the technique, which was developed by an Italian doctor.

His team had also enhanced it by fully expanding the stent at the side branch artery so it transferred the regrowth-inhibiting drug to the part of the side branch where new narrowing was most likely to occur.

He was uncertain how the new technique's outcomes would compare with existing methods, but bench-top modelling suggested they would be a lot better.

"We expect that will translate into clinical outcomes - less problems in future: better blood flow, less chance of blood clots, easier to get access to the side branch in future if you have to treat something downstream."

Angioplasty is less invasivethan a heart artery bypass graftand requires only an overnightstay in hospital.

"This technique removes the need for many patients to undergo major heart surgery and they are able to exercise normally without experiencing angina pain," said Dr Ormiston.

The hospital is the only centre in the Southern Hemisphere ever invited to transmit to the main auditorium of the Euro PCR convention.

The proving and enhancing of the technique build on the work of the former Green Lane Hospital's cardiac team - now in Auckland City Hospital - in heart surgery on babies and valve replacement.