Executive Summary
Recently concluded mega trial, ISCHEMIA, concluded that for patients with no, controlled, or tolerated chest pain, procedures such as angioplasty (PCI) and bypass surgery (CABG) don’t offer more benefit over routine medicine treatment.
Considering that there is no different treatment required for such stable chest pain, stress tests are not needed routinely.
There is no need to do any emergency angiography in such patients.
If one falls into such category, who should decide whether to undergo angioplasty, bypass surgery, or a routine medical management? Believe it or not, the patient himself.
Don’t take any of this as a medical advice. But read on to learn more about this cardiology practice–altering development.
Recently announced results of a landmark heart disease trial, ISCHEMIA, is expected to change the cardiology practice going forward. In layman’s terms, the trial found that, in patients with stable heart disease, there was no short– nor long–term benefit of an angioplasty or a bypass surgery over the standard medicine treatment.
Medico-legal Disclaimer: I am trying to explain a very complex subject in simple English. Many complicated phrases do not have an exact equivalent in simple explanation. The readers are advised to read the links to each claim or statement to get the perfect medical terminology. Also, don’t take this article as a medical advice; it is not. It is to point out very new research that you and your doctor need to look at.
Some important phrases
I have used phrases that many patients understand. But the links that I have given are of the original medical literature. Unfortunately, it uses technical medical phrases. So you will need to understand a few phrases to make sense out of information:
- Angina: chest pain
- Stable angina: chest pain that does not change in frequency or worsen over time. This pain can occur on exertion or emotional stress and lasts for a few minutes. It goes away on resting or after taking appropriate medicines. Also called Angina Pectoris.
- Unstable angina: chest pain that occurs unexpectedly. It can happen at rest also. Also called Acute coronary syndrome.
- Ischemia: restriction of blood supply to tissue, leading to it not functioning properly.
- PCI (percutaneous coronary intervention): angioplasty
- CABG (coronary artery bypass graft): heart bypass surgery
The background
The results of a trial called COURAGE (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation) were presented in 2007. The trial looked at patients with stable heart disease, such as those who were detected to have a heart block on a stress test, but did not have symptoms of severe chest pain, or angina.
It was found that doing angioplasty on such patients made no difference to their getting a heart attack, or death due to heart attack or stroke, in future. This was observed over 15 years of followup.
Both the groups—angioplasty as well as medical management—had significant reduction in chest pain. The patients who underwent angioplasty had slightly lesser chest pain in the early years. However, there was no additional benefit by the end of 5 years, post–angioplasty.
These findings cannot be extrapolated to patients with unstable angina, which has different pathophysiological characteristics.
The main criticism of this trial was that the angioplasties used simple stents, since this trial was started 25 years ago. These stents are called bare–metal stents. Modern stents secrete certain medications that prevent clotting, and are called Drug–eluting or drug-secreting stents.
So there was a need for a trial that compared the outcomes of angioplasty that uses modern drug–eluting stents with medical treatment. ISCHEMIA trial was conceived for that.
ISCHEMIA trial
International Study of Comparative Health Effectiveness With Medical and Invasive Approaches (ISCHEMIA) trial is the most significant, comprehensive, long, and costly trial in cardiology in the last few years.
The trial involved 5,170 patients, 320 sites, 37 countries, 10 years, and US$100 million (very expensive). It was funded by an arm of the U.S. Government. So there were no conflicts of interest.
The trial selected patients who had stable ischemic heart disease and showed moderate to severe heart ischemia on stress test.
Conclusions
Allow me the use of medical terms, to quote from the American Heart Association Annual Scientific Sessions 2019:
The cardiovascular death, myocardial infarction, resuscitated cardiac arrest, or hospitalization for unstable angina or heart failure at 3.3 years occurred in 13.3% of the routine invasive group compared with 15.5% of the medical therapy group (p = 0.34). The findings were the same in multiple subgroups.
Invasive therapy was associated with harm (~2% absolute increase) within the first 6 months and benefit within 4 years (~2% absolute decrease).
Here is a YouTube video of Dr Gregg Stone, of Mount Sinai Hospital, New York, who was a part of the trial steering committee. It gives the important conclusions from the trial, albeit in technical terms.
Summary
In patients with stable ischemic heart disease and moderate to severe ischemia detected with stress tests, there was no benefit of routine invasive treatments, such as angioplasty or bypass surgery, compared with optimal medical therapy. There was also no benefit of the same regarding all-cause mortality or cardiovascular mortality / heart attacks.
Angioplasty and bypass surgeries were associated with 2% more harm compared to medical treatment within 6 months of the procedures. This was due to heart attacks that happen as a result of the procedures.
The procedures were associated with a 2% increased benefit by 4 years after the procedures due to reduction in spontaneous (not triggered by the procedures) heart attacks.
The results of ISCHEMIA trial do not apply to patients with current or recent acute coronary syndrome, highly symptomatic patients, left main stenosis, or left ventricular ejection fraction <35%. Sorry for the technical terms, again.
A detailed technical explanation, especially for doctors: Invasive strategy no better than meds for stable ischaemic heart disease.
Take-home message
The trial indicates that:
In a patient with absent, controlled, or tolerated chest pain, there is no need for an immediate or urgent angiography.
In such patients, use of standard medicines is safe, which is consistent with many other studies.
The patient should undergo a procedure, if he is willing to take a bit of short–term risk, for a little bit of long–term benefit.
In such patients, who should decide whether a medical treatment is better or an invasive procedure? Lo and behold, the patient himself.
Actionable tips
- If you have a heart condition, read the article above and go through the links.
Ask some trustworthy family doctor to explain you the conclusions of the trial. Your cardiologist may not have time to discuss this in detail with you, given the time constraints of his practice. - If you have minor chest pain, and you are advised a stress test, discuss ISCHEMIA trial with your doctor.
It is better to perform CT Angiography test, and rule out left main disease. A stress test may not change the treatment. - If you are advised an emergency angiography, discuss ISCHEMIA trial with your doctor.
If you have stable heart ischemic disease, you may not need angiography. - Discuss with your cardiologist as to which category your heart disease falls in: chronic or acute syndrome, symptomatic or non–symptomatic, etc.
If you fall in the stable ischemic heart disease category, decide whether you want to undergo a surgical procedure or a medical management in consultation with your doctor. - Don’t consult everything with Dr Google.
Respect your cardiologist and his opinion.
First published on: 20th January 2020
Image by Gerd Altmann from Pixabay