Thursday, December 30, 2010

MALAYSIAN INTERVENTIONAL CARDIOLOGY 1991-2000

To continue the story.
Well, when we had done 100 plain old balloon angioplasty ( POBA ), it was the beginning of 90's. Dont exactly remember the dates. I began to realise that balloon angioplasty was getting too expensive. Cost was becoming an issue. This is also an important development. In the 80s, CABG was costing about RM 12K-15K ( average ). Few private centers were doing it. When the CEO of SJMC asked me how to charge, I reasoned to myself that if POBA had a restenosis rate of 50%, then I must factor in two POBA for one CABG. So I suggested that POBA should have a total cost of about RM7-8K. We worked out a packaging cost, of about RM8K ( if one balloon was used ). At that time, the balloons were over-the-wire balloons and they were high profile. Each balloon cost about RM3K. When we started with single vessel disease, we could get by with 1-2 balloons. But when we started to do double and even simple triple vessels, we were using 2-3 balloons per case. The balloon cost was putting up the price of POBA. I was very concerned that if POBA was too expensive, and with a 50% re-stenosis rate, the PTCA program may not take off. Patients may opt for CABG ( coronary artery bypass surgery ).
So, I was looking high and low as to how to safely re-cycle balloons. From my UH days, I remember that we used to re-cycle diagnostic catheters, by washing them clean right after the procedure, packing them, and sending them for EO gas sterilisation. I did this with the balloon catheters. After a awhile, I found that the balloon failure rate was too high. The balloons failed, because I could not inflate them. There was of course no danger to the patient, but just that the balloons could not be used. I wasted all my effort. The balloon failure rate was almost 70-80%. This was mainly because the balloon had a central guide-wire lumen and also a balloon lumen to inflate and deflate. To help us see our balloon well, we had to fill the balloon lumen with diluted contrast ( 50-50, or 70-30 ). The contrast tended to stick in the lumen and was difficult to flash clean, and complete. So the retained residue crystals were causing a problem of blocked balloon lumen so that we could not inflate.
I began to look for a solution. It was obvious to ask the device company ( at that time there was essentially only one company). USCI Bards, we knew well from our UH days. The USCI Bards products were distributed by a local company called "Somedico". So I asked the local Somedico sales manager to look around and see which country was doing angioplasty and which country was using re-cycled balloons. We found that of all the developed country doing angioplasty, France, French interventionist were using re-cycled balloons safely ( because in France, angioplasty was not insurance re-imbursible ).
They were very kind to me. They contacted their French counterpart and arranged ( also paid for my air-ticket and lodging in Paris for a week. ) for me to visit and learn from the French. I left to go to Paris, in the summer of 1991. My tutor there was Dr Thierry Corcos who was working in his own Interventional Center in Les Cheney, just outside Paris. I remember that I had to take a train out there and walk back from the train station to my hotel, each day, after the cases were done. I use to buy French loaf ( which I like ), and eat on the way back to the Hotel. Anyway, I learn that re-cycling was simple. All they did ( and it was safe, so they say ), was to clean the balloon catheter thoroughly right after each use. Drip the lumens overnight, and then soak it in 50% cidex. Cidex is an antiseptic agent that is use regularly for cleaning medical equipment. It is bactericidal. When you need to use the catheter, just take it from the cidex tray, and soak it in water, flush it thoroughly free of cidex, and then it is ready for use. In the new millennium, we have stopped using cidex, although I still hear of some centers which are still using this method. We stopped using in this millennium because of the fear of AIDS, Hepatitis C, and of course the toxic fumes from concentrated cidex, that can potentially harm the lungs.
But the good news from Les Cheney, was that, one day, while we were doing a case, Dr Corcos mentioned to me that his friend in Toulouse, was using a metal stent with his POBA and getting good results. His short term and intermediate term results were better and that he could treat acute dissection ( the bain of all interventionist then ), without the need to go for emergency bypass. So I asked him to arrange for me to go and observe and meet his friend in Toulouse. So he called his friend in Toulouse who turned out to be Dr Jean Marco and made the arrangements for me. I took an overnight train from Paris to Toulouse and spend a day at the Clinic Pasteur in Toulouse. On that day, I observed Dr Marco put down two coronary stents. Both in the RCA. They were the original PS 153 ( Palmaz Schatz stent by JnJ ). The post stent angiographic results were seductive. Th arterial lumen was so wide and smooth. It was like nothing that you can achieve with the best POBA. I was most impressed.
Upon my return from Paris, I asked the JnJ manager here for permission to use the stent ( PS-153 ). The regional manager was from Cordis Niche. She was very kind, and told me that since the stent was not FDA approved ( this was in 1991 ), I had to be proctored and become an FDA co-investigator, in order to use the stent. So I filled in the paper-work and became a FDA co-investigator for the Palmaz Schatz stent, the legendary PS-153. For proctoring, the nearest center to me was in Japan, the Kokura Memorial Hospital. The senior interventionist there was the world famous, Dr Masakio Noboyushi ( monthly angiography to study POBA re-stenosis fame ). I had to get his permission. JnJ arranged for me to meet him, late one night during the November 1991 AHA Annual Scientific meeting. Noboyushi san gave his blessings. I was on the way to Kokura at Kita-Kyushu in the spring of 1992. I spend 10 days there under-studying him, received his approval and upon my return purchase the stent to use in my patients.
The first coronary stent in Malaysia was implanted on 13th May 1992, in a lady in her mid-60s who had a single vessel disease-the RCA. The PS-153 then was mounted on a SDS ( stent delivery system ), covered with a sheath. The stent was a slotted tube, closed cell design and the crossing profile was 5F. I had to use an 8F guiding catheter. It was quite a chore, and you had to be very careful, as stents could get dislodged. It was like driving a bulky military truck into a small coronary artery. Also, post-stenting anti-coagulation regimes were scary. It included 50% dextran, aspirin and warfarin. Bleeding became a major issue. Blood transfusion were frequent. Groin hematomas were frequent. Anyway, this patient did well. The stent remained patent and she lived to a good old aged, and passed away a few years ago.
During this venture, I became acquainted with Dr Richard Schatz. Nice man. He must have made a lot of money, with the PS-153 patent and also the shares in JnJ.
I was reminded that I forgot to mention another important milestone in Malaysia. That is, on September 1992, the country launch the National Heart Institute, built at taxpayers expense, to provide cardiac care to the Rakyat. It is a corporatised body, funded by taxpayers, for care of public patients and also "fee for service" private patients. For very many reasons ( that may form another story ), in my opinion, it has not been able to fulfill its role well, for the tremendous amount of money that the tax payer has put into it, causing the government to set up its own heart centers in government hospitals.
After another two years, the results of the STRESS ( USA ) and BENESTENT ( European ) studies were released, showing that the PS 153 was safe and reduced re-stenosis, and was also good to treat acute dissections. The stent re-stenosis rate was about 20-30% ( quite an improvement from 50% with POBA ). With the released of these two pivotal studies, the PS 153 received FDA approval. Its result were duplicated by many centers. And as the saying goes, because of the PS-153, coronary stents became an established device to treat CAD.
But the scene was not so clear then. Why? Firstly, there was a competitor to the PS-153 on an SDS system. It was the Gianturco Rubin ( GR ) coronary stent. This was a coil designed stent. Because it was of coil design, it was easy to put down, but also because it was of coil design, it had a very high rate of re-stenosis ( almost 80-90% ). It was too open and lacked hoop strength. Some of my colleagues in this country, did not liked being proctored ( despite my offering to arrange for them ), chosed to use the GR stent. They quickly learned that almost all of them came back.
Besides the stents, the 90's also see the experimental use of many other devices, like the lasers, laser balloons ( hot balloons, cold balloons ), atherectomy devices, rotablators, and some others which I have forgotten. I remember the CEO of SJMC calling me for tea and asking me to see if the hospital should buy the laser machine to laser the coronary artery. This was the period when lasers in medicine was the cure for everything. It was the in-thing. I told him that we should not touch the lasers as it was bad for the coronary arteries. In fact, accept for rotablators, all the other devices slowly fell out of favour, one by one, and we settled with coronary stenting as the mainstay of treatment for CAD. I did go to Madras to spend 2 weeks with Dr Matthew Samuels ( my good friend there at Apollo Hospital ) to learn how to use the rota. He was the king of rotas. He could rotablate anything. Of all the devices, we chosed the two, that have lasted the test of time. Of course, in the early 90's, I didn't know that.
The other significant development that should be mentioned was the strategy for PCI ( percutaneous coronary intervention ). When we first started in 1988, we were taught to do the diagnostic angiogram, and stage the angioplasty for 2 weeks later or a month later. This was medically sound as it allows the patient to seek other opinions and also allowed a better planned PCI procedure. It also allowed us to schedule cardio surgical back-up. However, after the initial few months, some patients complained and requested that for convenience and also cost savings, they would prefer to have it all done in one go. After some initial reluctance, i decided that it made sense to have it all done in one go. It was cost savings and many of my patients were self pay ( out of own pocket ). Also, by this time, we were stenting alot and so cardio-surgical backup became unnecessary. Sometimes I regret this decision, because it realised now, that it can be missused by some, to do unnecessary stenting and unnecessary PCI. The interventionist became the one to diagnose the illness, and also the one to execute treatment, all in one day. If the interventionist is less than credible, there could be miss-use. The patient does have have a chance for a second opinion.
Anyway, the 90's saw the wide spread use of the bare metal stents in PCI. The anti-coagulation regimes became simpler. There was no longer any need for Dextran ( we have seen dextran causing asthma and heart failure ), and warfarin. We simplified the regime to aspirin ( low dose ) and ticlopidine ( this were the days before plavix ). Then the stents became lower profile. The initial stents were made with surgical grade stainless steel ( or 316L grade ). The later stents were made of cobalt chromium, which was a strong alloy, and so the stents could be made thinner, with lower profile. They then became 7F and then 6F compartible. The PS-153 slowly became obsolete. My overseas colleagues reported re-stenosis of 20-30%. s usual, after 100 coronary stents, we publishes our experience in the Malaysian Medical Journal. We had a re-stenosis rate of about 14%, bearing in mind that ours was clinical re-stenosis and many of my overseas colleagues were talking about angiographic re-stenosis, which was obviously more sensitive, but which in my opinion was unnecessary.
After the PS-153, a whole host of coronary stents were produced by a whole host of companies. The GR stent also became obsolete, and the company ( Cooks ) stop this line and went on to other devices. Other companies like Boston Scientific came in with their stents, and also AVE, Guidant ( now Abbott ), Medtronic International ( previous USCI Bards ), with their stents. Now we are spoilt for choice. There is even a made in India stent, and a made in Singapore stent ( the S stent ). The marketplace is so competitive.
However, a re-stenosis rate of 20-30% was still higher. Every third patient would complain of angina again and would need a repeat procedure. Things were not yet good enough.


To be continued. " Malaysian Interventional Cardiology 2000-2010".

1 comment:

tcorcos said...

Hello Dr Ng, Ni Hao ! Selamat Sore!
I hope you are alright. I read my name on your blog and I cannot realize that 20 years have passed.
I hope you to see you in the future. My email address is tcorcos@free.fr and my mobile phone number + 336 14 69 90 68.

Best Regards

Thierry