The almighty cardiac stent

Mr. Jones had the scare of his life. At only fifty-six years of age he never expected to have significant build-up of cholesterol in his arteries, let alone chest pain. He first noticed the chest pain while mowing his lawn and then again whenever he over-exerted himself. Eventually, although not noticing a change in the chest pain, Mr. Jones could no longer ignore it. He met with his primary care doctor who, concerned that it was related to his heart, referred him to a cardiologist.

The cardiologist shared the concern and, given the high suspicion, promptly ordered a cardiac catheterization – a procedure in which a wire is traversed, usually from the right groin, up to the heart to inject the arteries with dye and evaluate for blockages. Mr. Jones’ catheterization showed various small build-ups of cholesterol but also one blocking over 70% of an artery.

Judging this blockage as the likely cause of Mr. Jones’ symptoms, the interventional cardiologist by inflating a balloon opened the artery and then expanded a stent (a wire mesh) in place to help keep it open.

(http://www.youtube.com/v/9FPapBbbS4o&hl=en&fs=1)

Afterwards the cardiologist shared with Mr. Jones the pictures of what he had done. The significantly blocked artery, now with a stent, looked quite good.

On leaving the hospital that day, Mr. Jones exhaled a sigh of relief feeling better, reassured and grateful that a significant blockage in his artery had been fixed, opened up, and that he had bought himself more time to enjoy with his family. The cardiologist left work feeling good for having helped a patient and for a job well done.

Of course, the real story is missing. The cardiologist had helped the patient, but Mr. Jones and the cardiologist may have lost the big picture that day and perhaps perpetuated a myth.

Dispelling the myth

Data from studies investigating stents for heart disease do no prove that patients with stable blockages in the arteries of their heart do better in the long term with early placement of stents than merely management by medications. That is, studies do not show that stents allow people to live longer or have fewer heart attacks than those treated with medications.

The real benefit of stents is their ability to improve symptoms, chest pain or shortness of breath, shortly after they are placed. This benefit over medications too dissipates with time. One study that looked at patients five years after either initial placement of stents or management by medications showed similar amounts of chest pain between the two groups.

Why then does the information get lost and the myth perpetuated?

Part of the reason that the myth is perpetuated is psychological - we as patients want stents to solve the problem. On being diagnosed with blockages in our arteries, faced with heart disease and our own mortality, we, like Mr. Jones, want to think actions can be taken to quickly reduce our risk of heart attacks and prolong our life. We want to sleep better. The stent that quickly and visually opens an artery and makes us feel better reinforces the idea.

The before and after pictures of the clogged artery are also visually quite compelling to doctors. Doctors want to believe. They are familiar with studies, but doctors only see real people in their office, individuals like Mr. Jones. They don’t want their patients only on average to do better, but they want Mr. Jones to do well, not have heart attacks and live longer. Placing stents and seeing a quick relief of chest pain and shortness of breath reinforces that idea to doctors as well, even if it’s inaccurate.

The interventional cardiologist on inserting the dye and diagnosing the blockage is there with a wire in Mr. Jones’ groin ready and able to open the blockage. Does he ignore the prominent blockage, not act, and remove the wire? How does Mr. Jones react? Patients appreciate feeling better right away and generally equate that with a better level of care. Imagine explaining to Mr. Jones that he will instead be only started on medications and that, despite the significant blockage in his artery, he should do just as well as his friends with stents.

The idea in medicine of not “doing something just because you can do something” can be one of the most difficult lessons for doctors to learn and for a patient to accept. As a patient who presents to a doctor with a problem and as a doctor in charge of making this person better, there is always a pressure to do something, anything. The pressure to do something, anything, however can cause people to neglect the associated risks.

Cardiologists as specialists

Specialists like cardiologists feel this pressure more than anyone. As a specialist, the expert, the cardiologist is expected to offer solutions others can’t and make everything better. If the cardiologist does nothing and/or merely adjusts medications patients may wonder why they are seeing the specialist. The patients may stop seeing the cardiologist.

Mr. Jones was referred to the cardiologist by another doctor (likely one who also specialized in internal medicine but decided not to specialize further). The cardiologist therefore may interpret the internist’s referral of Mr. Jones as an interest in doing more, seeing an intervention performed. The internist may just want assistance in adjusting medications or a second opinion but that idea may not be transmitted. An internist can adjust medications and not put in a stent just as a cardiologist can. The cardiologist may fear that if he doesn’t place a stent and merely adjusts medications, that the internist will send patients to a different cardiologist who will do more and intervene further.

What is a cardiologist without patients? The salary of an interventional cardiologist may also indirectly be tied to the number of procedures he does and the stents he places. (As an aside, I in no way want to diminish the role that cardiologists play in the care of patients.)

Stents have no role?

Does that mean patients with a blockage over 70% and stable chest pain shouldn’t have a stent placed? Clearly that is a discussion patients can only have with their doctors, but it means that if people are relying on stents to open their arteries and keep them from having fewer heart attacks and living longer, they may need to rethink their assumptions.

For future discussion: the theoretical reasons as to why stents don’t necessarily save lives or prevent heart attacks, why stress tests in asymptomatic patients are generally not recommended, and what do we know that prevents heart attacks and saves lives.