(Brief) Reaction to Article: "Percutaneous Coronary Intervention versus Coronary-Artery Bypass Grafting for Severe Coronary Artery Disease"

"Percutaneous Coronary Intervention versus Coronary-Artery Bypass Grafting for Severe Coronary Artery Disease" by Patrick W. Serruys, M.D., et. al. (New England Journal of Medicine (NEJM), March 5, 2009)

I was drawn tonight to the above NEJM article by an article posted on the New York Times (NYT) website, "Heart Stents Found as Effective as Bypass for Many Patients" by Roni Caryn Rabin. This NEJM article has yet to be published in print but was published in advance online.

My first two reactions to the study (and there were many others but these I feel are the most important) :

(i) The follow up of patients was only for one year. I suspect the majority of us are hoping to live much longer than one year after our procedure... Follow up at, let's say, 5 years would be much more valuable, and I think much more revealing. There are usually two periods of divergence between patient groups that we see when evaluating vascular surgeries - such as evaluating the benefits of placing stents versus performing surgery with carotid stenosis (blockages of the arteries that supply blood to the brain and increase people's risk of strokes): early on and long term. Surgeries typically have higher risks early on but lower long term, and with stents the reverse is typically true. Thus, a further divergence between patient groups after one year would not be a surprise to the medical community.

(ii) There are significant differences between the medicines the two groups received after their procedure (even simple medicines like aspirin and cholesterol lowering medicines like statins - drugs that we know reduce strokes, heart attacks, etc.) I encourage you to look at Table 2 of the article and compare the two columns, PCI (patients receiving stents) and CABG (patients receiving surgical bypasses). The patients who had bypass surgery consistently, in regard to each of the medicines listed, were less like to receive the medical standard of care. Those differences make the comparison between the groups of patients much more difficult. Rather than comparing apples and apples, the study is forced to compare more apples and oranges. One wonders at how the two groups would have differed if they had both received the general standard of medical care after their procedures. Perhaps the surgical bypass patients would have done even better. One would expect so.

By the way for the women out there, 78% of the study participants were men - a flaw that continues to plague studies, even today.

If you are interested, I encourage you to attempt to read the article - you will understand more than you think and be able to make your own opinions. If not, I encourage you to read the editorial accompanying the article, Coronary Revascularization in Context by Richard A. Lange, M.D., and L. David Hillis, M.D. (NEJM, March 5, 2009).

Consumers should be aware of the limitations of what they read and are told. For those interested, previous entries on related subjects: The almighty cardiac stent and Reaction to Article: "Communicating Medical News -- Pitfalls of Health Care Journalism".