EXCEL, SYNTAXES Analyses Spotlight Periprocedural MI Controversy

0 Comments

Investigators from the EXCEL trial have doubled down on the July publication of their study’s outcomes based on an alternative definition of myocardial infarction (MI) resulting from coronary revascularization, a key part of the controversy that has dogged EXCEL for a year or more.

The latest, more granular EXCEL analysis pits periprocedural MI (PMI), as defined in the trial’s protocol, against PMI according to the more stringent third Universal Definition Of Myocardial Infarction (UDMI). The stakes for EXCEL’s message are high because PMI is part of the composite primary end point.

The new analysis concludes with a preference for interpreting EXCEL — which compared percutaneous coronary revascularization (PCI) and coronary artery bypass (CABG) surgery in patients with left-main coronary artery disease (LMCAD) — using the protocol-specified PMI definition, which was based solely on levels of CK-MB (and sometimes troponin), rather than the UDMI. That alternative definition adds clinical signs, electrocardiography (ECG), or imaging to the biomarker assay criteria.

In a separate publication, SYNTAX Extended Survival (SYNTAXES) study investigators tackled the same issue by reinterpreting their own trial, also with PMI in its primary end point, according to five separate published PMI definitions. Those definitions varied according to whether they considered clinical, ECG, or imaging criteria along with biomarker assays.

In SYNTAXES — which compared PCI and CABG in patients with triple-vessel coronary disease, LMCAD, or both — PMI at PCI predicted 10-year mortality by all five definitions. PMI at CABG predicted mortality only at 1 year, and only when defined by biomarker assay plus the other clinical, ECG, or imaging criteria, the report notes.

The new analyses, both published September 28 in the Journal of the American College of Cardiology, meticulously illustrate what many EXCEL trialists and observers have already acknowledged: that the rate of PMI associated with coronary revascularization