Several recent articles, published earlier on this website, discussed the excessive use of cardiac catherization and stenting in the evaluation and treatment of coronary artery disease.
Despite guidelines, issued repeatedly by the American Heart Association for evaluation of patients suspected to have heart disease, it is not uncommon for these to be ignored.
A recent article published by Patel et al. in the NEJM showed that in 60% of non-urgent or emergent cases, cardiac catherization, performed as a “shot in the dark”, resulted in the finding of normal (i.e. no blockages) coronaries. In another study 30% of cardiologist indicated they would order a cardiac catherization for other than clinical indications.
As part of a routine pre-procedure authorization, patients are frequently asked to allow for placement of a stent if a blockage is found. Most patients will agree to such a request, resulting in the placement of unnecessary stents in 30% of procedures.
What does this mean?
- Every procedure has its own built-in risks & benefits. If done for the wrong reasons, a patient is only exposed to the risks involved.
- A stent destroys the coronary artery locally, occasionally blocks important side branches and often sends debris downstream, damaging the very heart muscle it intends to protect. Once a stent is in place, expensive medications are needed to keep it open, despite of which there is a more than 10% risk of closure within the first year.
- If you undergo catherization for the wrong reasons and allow for placement of a stent “as long as we are there anyway”, you are on a slippery slope, where you from now on need to be treated for a new disease (your stent), probably requiring more stent placements to fix the one that is going to fail.
- Coronary artery disease is part of an industry where stenting alone generates 15 Billion $$/year in the US alone. Unlike coronary artery bypass grafting (CABG), stenting has not been shown to improve life expectancy, except in some patients with an acute heart attack.
- During the last 10 years, CABG has been reduced to a rarely used solution for treatment of coronary artery disease, used only when a stent placement has failed or proven impossible. There are numerous reasons for this, some of which include a (very natural) fear of pain and possible complications on the part of patients. A major reason however may well be that there is an enormous financial incentive for a cardiologist to keep treatment in-house, referring to a partner rather than another specialist and heavily supported by a for-profit medical industry.
- When used appropriately, stenting is an appropriate tool in the arsenal of treatments available for CAD. If not, it is just another way by which health care costs have reached stratospheric levels.
What can you do?
- If you have new symptoms, especially if they are typical of angina, you need to see a doctor now!
- If it is not an emergency, you have time enough to go through a proper evaluation.
- There are a number of logical steps that lead to elective cardiac catherization, such as proper evaluation that should at a minimum include an EKG and a stress test.
- Older men are at a higher risk for heart disease than women of the same age. So are diabetics.
- Take the “calculate your risk for heart disease” test. If your risk score is high, you are more likely to have coronary artery disease.
- Women get heart disease even before menopause, but often have atypical symptoms such as unusual fatigue (“tired all the time”), particularly if smoking and/or “metabolic syndrome” is present. Women often have smaller caliber coronary arteries as compared to men, making stent placement riskier.
- There is place for medical treatment, diet and exercise as the primary therapy. In fact, irrespective of whatever intervention is chosen, none should be given in isolation of these three.
Tell me what you think,
Thank you Dr. T for this interesting blog, and drawing attention to this article, which I hadn’t read until I saw your blog entry.
It’s incredible to think about how many caths are done in low and moderate risk patients without any kind of non-invasive testing (even an EKG!), and I had no idea that of patients without known coronary disease who are cath’d, so few actually have the disease. They make a great argument for the need for a risk model to assess risk for CAD, prior to diagnostic cath.
That said, I think, as the authors point out that a major flaw is the grouping together of any type of non-invasive test together (e.g. EKG together with a stress), which I hope explain why non-invasive testing positivity is associated with increased risk of significiant coronary disease it is not as predictive as the Framingham risk model.
I look forward to your next entry.
Thanks Dr. T for this interesting blog.
I am a medicine resident in the northeast US and I also found some of the findings of this article pretty amazing:
“Noninvasive testing (resting electrocardiography, echocardiography, computed tomography [CT], or a stress test) was performed in 83.9% of the patients before invasive angiography…A noninvasive test was performed before angiography in 17.1% of low risk patients, 15.9% of intermediate-risk patients, and 15.0% of high-risk patients (P<0.001)." (p.890)
How is that possible??? Ridiculous.
While it is known that caths are done for reasons other than cardiac risk assessment (e.g. pre-op evals etc) the indications for this are (as far as I know) are few. Why are so many caths being done?
I have to say I don't think ANYONE at my institution would have a cath without an EKG and either a positive stress, unless there was concern for active ACS.
As the authors of the paper say, "Given that the primary benefit of invasive treatment for obstructive coronary artery disease is relief of symptoms, we think that the threshold for invasive angiography may need to be higher in asymptomatic patients, for whom the potential benefits remain uncertain."
Another interesting finding was how poorly "non-invasive testing" correlated with presence of significant CAD. I think this (I HOPE this) is secondary to the broad definition of what an acceptable non-invasive test was for risk assessment (e.g. both a stress, an echo and an EKG). I would hope a properly administered stress would correlate more closely.
That said, I have to say that risk factors for cardiac disease being more predictive than a positive stress was also interesting.
You are welcome. I try to expose controversial issues, of which unnecessary procedures is one. In this situation, it is the lack of an independent gatekeeper, who will not financially benefit from a referral. Another issue is the general opinion held by non-surgeons that an operation should only be used as a treatment of last resort. More about that later,