… or, An Angioplasty Also Won’t Make You Taller

Over a million coronary angioplasties are performed in the US each year.  In this procedure a thin tube is threaded into a narrowed coronary artery.  Through this tube a balloon is inflated to open the narrowed artery, and then a stent (a metal mesh tube) is placed to keep the newly expanded artery open.

Some large well-designed studies in the last few years have taught us that angioplasty is a life-saving procedure in the setting of an acute heart attack but that in patients with chronic stable angina (chest pain due to coronary artery narrowing) angioplasty decreases the pain but doesn’t prevent heart attacks or save lives.  (I summarized these findings two years ago, so see the link below for more background on angioplasty.)

So have doctors and patients absorbed this new sober understanding of the limited benefits of angioplasty?  A fascinating study in the current issue of Annals of Internal Medicine answers this question.

The study interviewed over a hundred patients who were scheduled for possible angioplasty and 27 cardiologists who were involved in their care.  None of these angioplasties were for an acute heart attack.  Interestingly, only two thirds of the patients suffered from chest pain.  The patients and cardiologists were surveyed about what benefits they should expect from the angioplasty.  The difference between the cardiologists’ and the patients’ answers were startling.

The cardiologists reflected an understanding of the recent studies.  They mostly said that they expected the patients to have less chest pain after the procedure but that they didn’t expect it to lower their risk of future heart attack or death.

The patients’ opinions were very different, despite the fact that they each had spent a significant amount of time with a cardiologist who explained the procedure to them.  88% of them believed that angioplasty would reduce their risk of heart attack, and a similar number believed that angioplasty would reduce their risk of a fatal heart attack.

What’s going on here?  Are the patients being misinformed?  Are they signing up for an invasive procedure under false hopes?  It’s hard to be sure.  The investigators don’t know the content of the conversation between the cardiologists and the patients.  It’s possible that the cardiologist just detailed the risks, not the benefits.  Or it’s possible that the patients were told the benefits but mistakenly assumed that if the cardiologist is recommending the procedure, it must also prevent heart attacks and prolong life.

It’s also possible that the findings are biased by the fact that all the patients selected for the study had already been scheduled for a possible angioplasty.  That means that the most well-informed patients who had elected not to proceed with angioplasty would not have been included.  That’s like surveying customers in an organic food store and finding that most of them have falsely elevated beliefs about the benefits of organic food.  All the skeptics of organic food aren’t in that store and would be missed by the survey.

Regardless of the specific cause of the patients’ misunderstanding, the study is a good reminder that doctors perform risky invasive interventions on our patients every day.  We owe our patients education about why we’re recommending the procedure.  Patients owe it to themselves to ask specific questions about benefits, risks and alternatives.

Learn more:

Annals of Internal Medicine article:  Patients’ and Cardiologists’ Perceptions of the Benefits of Percutaneous Coronary Intervention for Stable Coronary Disease

Bloomberg Businessweek article:  Many Heart Patients Place False Hope in Angioplasty

My post in 2008 summarizing the benefits of angioplasty:  For Most Heart Patients Medicines are as Good as Angioplasty