What is a successful angioplasty?

Against my instincts I got stuck into Lord Winston’s Superdoctors programme on BBC 1 tonight (28/08/08).

Lord Winston comes across as a nice man and watching him with grieving parents, it is obvious that he took the time to go to the ‘bedside manner’ lectures at medical school.

Lord Robert is, of course an infertility expert and not a heart specialist, and it shows. He made the statement that angioplasty is 90% successful. I suspect that he, like most people,assumes that if an operation is 90% successful it means that 90% of people are better off. But that is not what 90% success means in angioplasty terms.

What Professor Winston was talking about was the immediate post operative result and it is certainly true that at the end of 90% of angioplasty procedures the patient is still alive and has a nice looking section of artery where there was previously a narrowing. In other words patients can be confident that their cardiologist will be satisfied with his handiwork 90% of the time. Unfortunately, it tells us nothing about whether the patient is better or worse off. But we do have evidence from large trials.

The recent COURAGE trial that compared angioplasty with good medical treatment in stable angina showed that angioplasty didn’t prevent heart attacks and the minimal improvement in symptoms and quality of life didn’t last. The RITA-2 trial published a decade earlier showed the same result so no-one should be surprised that angioplasty isn’t very successful at treating stable angina compared to good medical treatment. To be clear, the situation is different in heart attacks where research shows that angioplasty does seem to help patients if it is done quickly enough.

Lord Winston made a point of mentioning the importance of the placebo effect. This is where patients feel better even if they receive a dummy treatment. He emphasised the need for studies to make sure the benefits of operations were not simply the placebo effect. It is therefore surprising that he failed to mention that the minimal and temporary benefits of angioplasty could easily be a placebo effect. I guess that the cardiologists he spoke to were too embarrassed to tell him that we have never conducted a placebo controlled study of angioplasty.

Few people know about this but I think they should. When I used to do angioplasty I told patients so they could make an informed decision whether to take the risk or not. I was always struck by how few patients were willing to have angioplasty once they knew these facts.