A stent--just in case

Burt came to me last week. He'd received a stent a few months earlier. He'd been feeling fine except for some fatigue. A nuclear stress test proved equivocal, with the question of an abnormal area of blood flow in the bottom (inferior wall) of the heart.

"The doctor said I had a 50% blockage. Even though it wasn't really severe, he said I'd be better off with a stent, just in case."

Just in case what? What justification could there be for implanting a stent "just in case"? (The artery that was stented did not correspond to the area of questionable poor blood flow on the nuclear stress test.)

Just in case of heart attack? If that's the case, what about the several 20 and 30% blockages Burt showed in other arteries? The cardiologist was apparently trying to prevent the plaque "rupture" that results in heart attack by covering it with a stent. Why stent just one when there were at least 7 other plaques with potential for rupture?

That's the problem. And that's why stents do not prevent heart attack (unless the stent is implanted in the midst of heart attack, when the rupturing plaque declares itself.) Of course, when no plaque is in the midst of rupturing, as with Burt, there's no way to predict which plaque will do so in future. Since only one plaque was stented, there is a 7 out of 8 chance (87.5%) that the wrong plaque was chosen. And that's assuming that there aren't plaques not detected by catheterization angiogram; there commonly are. The odds that the right plaque was chosen would be even lower.

In other words, stenting one blockage that is slightly more "severely blocked" in the hopes of preventing heart attack is folly. If it's not resulting in symptoms and blood flow is not clearly reduced, a stent can not be used to prevent plaque rupture. A stent is not a device to be used prophylactically. It is especially silly when an approach like ours is followed, since plague progession is a stoppable process.

Note: This issue is distinct from the one in which symptoms and/or an abnormal stress test show clearly reduced blood flow and flow is restored by implantation of a stent. While some controversies exist here, as well, a stent implanted under these circumstances may indeed provide some benefit.

Comments (3) -

  • Anonymous

    3/26/2007 12:45:00 AM |

    Interesting blog.  I have a question: would you be able to offer some comments on Dr. Ornish reversal programme and low fat vegan diets (in reversing CHD), based on your professional experience?

    We are having a little discussion about various pros and cons of various therapies and dietary approaches on the Web MD forum:


    We would really welcome you and would greatly appreciate some professional comments.  Sincerely,
    Stan Bleszynski (Heretic)

  • Dr. Davis

    3/26/2007 11:36:00 AM |

    Super low-fat diets, while an improvement over a conventional modern American diet of high saturated fat and processed foods, seriously exagerrate the small LDL particle pattern that is among the most powerful causes known of heart disease. It also reduces HDL and raises triglycerides, sometimes substantially. Dr. Ornish would argue that these are inconsequential changes, since his patients regress. Unfortunately, the methods he uses to gauge regression of atherosclerotic plague are flawed: angiography and nuclear imaging. Both can be envisioned as measures of flow, not of atherosclerotic plaque. Only CT heart scans or intracoronary ultrasound actually measure artery plaque. I tell my patients that, if you want heart disease, follow the American Heart Association diet. If you want heart disease and diabetes, follow Dr. Ornish's diet.

  • Cindy

    3/28/2007 12:47:00 AM |

    I know several people who have gone for a "routine" check with a cardiologist, sent for an angio, and ended up with at least 1 stent. (NO symptoms prompted these visits, just "high cholesterol".

    I also know a couple of people that have 9, 10, or more stents!