# Periprocedural Myocardial Infarction After Coronary Artery Bypass Grafting: Current Clinical Practices and Future Perspectives

## TL;DR

This paper explores how doctors currently define heart attacks near the time of heart bypass surgery and suggests the need for a unified standard.

## Contribution

The study identifies current practices and proposes the need for a CABG-specific PMI definition with high diagnostic accuracy.

## Key findings

- Most respondents use the UDMI-4 definition for PMI.
- Biomarker thresholds for PMI diagnosis vary significantly.
- Sensitivity is prioritized over specificity for defining PMI.

## Abstract

The definitions of periprocedural myocardial infarction (PMI) after coronary artery bypass grafting (CABG) are heavily debated. A European Association for Cardiothoracic Surgery (EACTS)-endorsed international survey was conducted to evaluate current clinical practices and to reach a consensus-based agreement on the diagnostic characteristics required for a potential future PMI definition.

The questionnaire complied with the CHERRIES guideline. A pilot version underwent iterative testing. The final version was distributed to all members of EACTS and allied specialties. The questionnaire evaluated definitions, biomarkers, and required diagnostic accuracy and was distributed between August-November 2024.

The questionnaire was completed by 175 respondents (surgeons: 71.4%, cardiologists: 20.6%, intensivists: 5.1%, other: 2.9%) from 29 countries. A specific definition of PMI was used by 46.4% of respondents (Universal Definition of Myocardial Infarction [UDMI]-4: 67.4%, Society of Cardiovascular Angiography and Interventions [SCAI]: 16.3%, second Academic Research Consortium [ARC-2]: 6.1%, other: 10.2%). Respondents identified biomarker concentrations defining PMI with supporting (imaging) evidence (high-sensitivity cardiac troponin T [hs-cTnT]: 489 ng/L, high-sensitivity cardiac troponin I [hs-cTnI]: 425 ng/L, CKMB-mass: 90ug/L, CKMB-activity: 100 U/L) and without (hs-cTnT: 931 ng/L, hs-cTnI: 1458 ng/L, CKMB-mass: 100ug/L, CKMB-activity: 300UL). The lowest acceptable sensitivity and specificity thresholds for a future definition were 95% [90%-95%] and 90% [80%-95%], respectively, while sensitivity was deemed more important than specificity (79.8% vs 20.2%, P < .001).

The use of PMI definitions varies widely, though UDMI-4 is most frequently employed. Our findings highlight the need for a standardized, CABG-specific PMI definition with robust diagnostic accuracy to enable consistent diagnoses and a common clinical language.

The diagnostic entity “periprocedural myocardial infarction” (PMI) is a widely debated topic in cardiac surgery.