ISCHEMIA: New Analysis Might Change Study Outcome Interpretation

A new ISCHEMIA analysis has shown its outcomes are highly dependent on MI definition. The original conclusion had shown a significant difference between invasive and conservative strategies using the most sensible definition of MI: troponin elevation. 

ISCHEMIA un nuevo análisis

When looking at events using MI definition as troponin elevation, we will see the conservative treatment reduces primary end point (combination of cardiovascular death, MI, hospitalization for unstable angina, cardiac failure, and cardiac arrest). 

This difference between strategies was driven by a greater number of periprocedural MI in the invasive arm. 

On the other hand, type I MI rate (universal definition of spontaneous MI) was significantly lower with the invasive revascularization strategy (be it PCI or CABG). This spontaneous MI cases were associated to worse prognosis as opposed to periprocedural MI cases. 

Other studies largely debated such as the COURAGE, the BARI 2D and the FAME 2 have not shown a reduction in spontaneous MI in the revascularization branch compared against optimal medical treatment. 


Read also: Virtual ACC 2020 | ISCHEMIA-CKD: Invasive Strategy vs. Medical Treatment in Higher Risk Patients.


The reasons behind the protection of revascularization against spontaneous MI remains nuclear, especially seeing as MI can happen in non-revascularized vessels or in non-obstructive lesions. 

Surgery can protect patients from events produced proximal to the anastomosis area, but it is far more difficult to explain in case of PCI. 

Another possible explanation might be the greater use of dual antiaggregation in the revascularization arm. 


Read also: High Risk Anatomy Challenges ISCHEMIA Outcomes.


And as this were not enough, 20% of patients allocated to the invasive strategy were not revascularized because of the absence of obstructive lesions, and this group also presented reduced spontaneous MI rate. 

Many assumed the aim of the ISCHEMIA was to find the benefit of PCI (as did the COURAGE) but, far from it; many of the patients randomized to the invasive strategy with angiography were not revascularized because of the absence of lesions treatable with stents, and many ended up in surgery. We need to demystify the link between angiography and stent. 

Knowing the anatomy helps us better select for or against strategies, and CT scans can be the best tool to do it. 


Read also: Virtual ACC 2020 | ISCHEMIA: Quality of Life, Not a Soft Endpoint.


As we have imagined since 2019 when presented at AHA, the ISCHEMIA will continue to raise questions for a long time. 

Original Title: Myocardial Infarction in the ISCHEMIA Trial: Impact of Different Definitions on Incidence, Prognosis, and Treatment Comparisons.

Reference: Bernard R. Chaitman et al. Circulation 2021, article in press. https://doi.org/10.1161/CIRCULATIONAHA.120.047987.


Subscribe to our weekly newsletter

Get the latest scientific articles on interventional cardiology

More articles by this author

ACC 2025 | FAME 3: FFR Guided PCI vs CABG 5 Year Outcomes.

Earlier studies comparing percutaneous coronary intervention (PCI) vs coronary artery bypass graft (CABG) have shown fewer events at long term for the surgical strategy.  However,...

CRABBIS Trial: Comparison of Different Provisional Stenting Sequences

Provisional stenting (PS) is the gold standard for percutaneous coronary intervention (PCI) in most patients with coronary bifurcation lesions (CBL). Moreover, recent studies such...

Andromeda Trial: Meta-Analysis of Drug Coated Balloon vs. DES in Small Vessel DeNovo Lesions

The use of coronary stents vs plain old balloon angioplasty (POBA), has allowed to reduce recoil and limiting flow dissection which were major limitation...

QFR vs. FFR: Is Coronary Revascularization Deferral Safe? Results from a FAVOR III Sub-Analysis

In cases of intermediate coronary lesions, functional assessment is recommended to aid the decision-making process regarding revascularization. There are several tools currently used to...

LEAVE A REPLY

Please enter your comment!
Please enter your name here

Related Articles

SOLACI Sessionsspot_img

Recent Articles

ACC 2025 | FAME 3: FFR Guided PCI vs CABG 5 Year Outcomes.

Earlier studies comparing percutaneous coronary intervention (PCI) vs coronary artery bypass graft (CABG) have shown fewer events at long term for the surgical strategy.  However,...

ACC 2025 | API-CAT: Reduced vs. Full Dose Extended Anticoagulation in Patients with Cancer Related VTE

The risk of cancer related recurrent venous thromboembolism (VTE) will drop over time, while bleeding risk will persist. At present, it is recommended we...

STRIDE: Semaglutide in Patients with Peripheral Arterial Disease and Type II Diabetes

Peripheral arterial disease (PAD) is a severe complication in patients with type II diabetes, primarily affecting peripheral vessels, especially below-the-knee (BTK) arteries. This condition...