Breaking News: The ISCHEMIA Trial--A Brief Summary
Updated: Dec 2, 2019
You will hear more about the ISCHEMIA trial in the coming months. See an excellent (but detailed) summary and interview with Dr. Block and Dr. Bhatt here.
Basically, it was a 3 year study of approximately 5,000 patients with known heart disease who had at least moderate ischemia (lack of blood supply).
The option was invasive catheterization vs. Optimal medical management.
Outcome: No surprises here...the invasive strategy (heart catheterization followed by stent placement or CABG) did not reduce cardiac death or heart attack.
Implication: You don't have to undergo a heart cath if you have moderate ischemia. You can be medically managed.
Remember: Both the ISCHEMIA trial and the COURAGE trial dealt with stable CAD, not acute conditions.
I find it quite amazing that the cardiology community is acting so surprised by these findings. We have known for decades that Angioplasty/stent placement (PCI) has never been shown to reduce death or MI in patients with stable CAD. This is not new information. It is only a new study. This study confirms what we already know.
Over a decade ago, the VA-based COURAGE trial demonstrated (despite study limitations) that there was no benefit of performing PCI/stent in patients with stable CAD and no or mild ischemia by stress testing. Even these results should not have been surprising, although study was considered a landmark revelation at that time.
What I have always told patients is that for stable CAD, the purpose of PCI/stent is to relieve symptoms. In patients with ischemic cardiomyopathy, left main coronary artery disease or left main equivalent multivessel disease--CABG can improve survival.
I encourage patients who have an abnormal stress test that demonstrates moderate or moderately severe ischemia to undergo imaging of their coronary arteries. This would be catheterization or CCTA. Typically catheterization would be recommended. If there is only stable CAD, then OMT (medical therapy) can be followed if the patient has no symptoms.
Talk to your cardiologist about the ISCHEMIA and COURAGE trials if you have an abnormal stress test.
Most patients never review the 'inclusion criteria' of a clinical trial and wrongly extrapolate the results to their situation.
Also, patients who participated in the ISCHEMIA trial, for the most part, underwent CCTA or had a previous catheterization performed. This allows the exclusion of left main disease which would benefit from CABG.
If you have asymptomatic, stable CAD and an abnormal stress test (evidence of ischemia) and do not have left main CAD, cardiomyopathy, etc. then OMT (optimal medical therapy) is reasonable.
Note: Understanding your heart condition is not difficult. Patients become frustrated and confused when doctors don’t explain things clearly. If you don’t understand what your doctor is talking about, then you won’t be able to ask meaningful questions. I hope that my posts provide you with a framework that you can build upon to become an active participant in your healthcare.
Gregg M. Yamada MD FACC
Disclaimer: I hope you find my medical blogs to be educational, pertinent, interesting, and thought provoking. The information provided is educational and should not be taken as medical advice. I am a doctor, but I am not your doctor. Please schedule an appointment with your doctor to discuss these issues and to determine what is right for you.
© 2019. Gregg M. Yamada, MD FACC. All rights reserved