Bleeding and Mortality
Dr. Gersh: It's very understandable why the hemorrhagic complications are reduced, but you are making the argument that these bleeds are responsible for an increase in mortality. There has always been a back-and-forth discussion about whether this is cause and effect. Is it just that people who bleed are more fragile, older, and have other problems, or is it that bleeding itself increases mortality? The fact that these trials have shown a reduction in mortality would certainly suggest a cause-and-effect relationship with bleeding. Would you agree with that?
Dr. Eleid: It suggests that, although there is still some uncertainty about the exact mechanism. We know that bleeding is tied to mortality in patients with acute coronary syndrome. With the reduction in medications, some of the antiplatelet agents will be discontinued, and part of the clotting cascade is activated when bleeding occurs. That could potentially play a role in the mechanism.
Dr. Gersh: The other factor is that people who bleed receive transfusions, and transfusions are not good for you. That could be another complicating factor.
Dr. Eleid: Definitely.
Dr. Gersh: What was the extent of the reduction in mortality in these trials?
Dr. Eleid: There was about a 1%-2% absolute risk reduction in mortality in the RIVAL study [in the STEMI cohort], and the RIFLE-STEACS study showed about a 4% absolute risk reduction in mortality.
Dr. Gersh: Were you surprised by that?
Dr. Bell: If we just go back to your original question, Bernard, about the bleeding, we have known about the link between bleeding and mortality for many years now, and we have always struggled trying to work out that link. How is it related? There are many confounders; you have already brought up some of the important issues here.
But now we have an intervention. It's a technique, not a drug, that has shown a significant reduction in bleeding, which led to a decline in mortality. If we think about those numbers, perhaps we shouldn't be too surprised. There is still a concern there about the patient who is at high risk of bleeding and, therefore, at higher risk for mortality. We can't answer that question today.
Think about those absolute differences, however. Let's put it in other numbers. The number needed to treat (NNT) to save a life, in those trials and in the meta-analysis, is about 50 patients. That is substantial; we are talking about an NNT to prevent a major bleed and save a life of 40-50 patients.
Dr. Gersh: That is very impressive. If you look at that in light of many other current treatments, that is a big difference.
So what are the disadvantages? Obviously, we will discuss why it has taken us so long to get to this point, but what are the drawbacks or potential drawbacks?
© 2014 Mayo Clinic
Cite this: Transradial Access in Primary PCI: A Call to Arms - Medscape - Feb 10, 2014.