Prognostic Relevance of Type 4a Myocardial Infarction and Periprocedural Myocardial Injury in Patients With
Matteo Armillotta1,2, Luca Bergamaschi1,2, Pasquale Paolisso3
1Department of Medical and Surgical Sciences, Alma Mater Studiorum, University of Bologna, Italy (M.A., L.B., F.A., A. Sansonetti, D.B., F.B., S.A., L.C., D.F., N.S., A.I., F.P.T., D.C., O.D.I., K.R., F.S., A.F., C.P.).
Circulation
|February 19, 2025
Summary
Periprocedural myocardial injury (PMI) after PCI in non-ST-elevation MI (NSTEMI) is common and linked to worse outcomes. A post-PCI troponin increase over 40% best predicts these risks.
Area of Science:
- Cardiology
- Interventional Cardiology
- Biomarkers
Background:
- Periprocedural myocardial injury (PMI) with or without type 4a myocardial infarction (MI) can occur in patients with non-ST-segment-elevation MI (NSTEMI) undergoing percutaneous coronary intervention (PCI).
- Current definitions and prognostic relevance of these events in NSTEMI patients undergoing PCI require further investigation.
- Identifying optimal thresholds for cardiac troponin I (cTnI) is crucial for prognostic stratification.
Purpose of the Study:
- To investigate the incidence and prognostic relevance of PMI, with or without type 4a MI, in patients with NSTEMI undergoing PCI.
- To determine the optimal cTnI threshold for stratifying prognostic risk in these patients.
- To validate findings in an independent cohort.
Main Methods:
- A cohort of 1412 NSTEMI patients undergoing PCI with stable or falling pre-PCI cTnI levels were analyzed.
- Patients were stratified into three groups: PMI with type 4a MI, PMI without type 4a MI, and no PMI, based on the Fourth Universal Definition of Myocardial Infarction.
- The primary endpoint was 1-year all-cause mortality; secondary endpoints included major adverse cardiovascular events (MACE) at 1 year. A post-PCI cTnI increase >20% with an absolute value ≥5 times the 99th percentile upper reference limit defined PMI.
Main Results:
- Out of 1412 patients, 17% had PMI with type 4a MI, 20.4% had PMI without type 4a MI, and 62.6% had no PMI.
- PMI was associated with increased risks of adverse outcomes, with type 4a MI patients showing the highest mortality and MACE rates.
- A post-PCI ΔcTnI >40% was identified as the optimal threshold for prognostically relevant PMI, confirmed in a validation cohort of 305 patients.
Conclusions:
- Periprocedural ischemic events are frequent in NSTEMI patients undergoing PCI and have significant prognostic implications.
- A post-PCI ΔcTnI >40% combined with an absolute value ≥5 times the 99th percentile upper reference limit is the optimal threshold for diagnosing prognostically relevant PMI.
- Recognition and accurate diagnosis of these events can improve risk stratification and management strategies for NSTEMI patients.
