Impact of troponin type and timing on the detection of periprocedural myocardial infarction and injury in the alpheus randomized trial

Background The ALPHEUS study evaluates the efficacy of ticagrelor compared to clopidogrel in preventing peri-procedural myocardial infarctions and major myocardial injury in patients undergoing complex elective angioplasty. Variability in cardiac troponin assay types and timing of measure may affect the detection and timing of myocardial injury or myocardial infarction. Purpose This sub-study of the ALPHEUS study aims to explore the relationship between the type of troponin assay, the timing of measurement, and the detection of peri-procedural myocardial infarction and injury. Methods The ALPHEUS randomized trial included 1910 patients admitted for elective PCI of complex coronary lesions. Patients with clearly documented troponin assays (conventional or high sensitivity) were included in this post-hoc analysis. Patients with missing troponin data or incomplete procedural information were excluded. Troponin measurements were obtained at predefined time points (day 0 (D0) and day 1 (D1) post-procedure) and analyzed across three groups: standard troponin I/T (non-HS T), high-sensitivity troponin I (HS-Ti), and high-sensitivity troponin T (HS-Tt). The classification of myocardial infarction (type 4a and 4b) and major myocardial injury was based on the 4th Universal Definition of MI. Comparisons between groups were performed using the Chi-square test for categorical variables and the Kruskal-Wallis test for continuous variables. Multiple comparisons were adjusted using Bonferroni correction. A p-value < 0.05 was considered statistically significant. Results We analyzed 1879 patients according to their type of troponin dosage: n=296 for those evaluated with-HS T, 356 with HS-Ti, and 1227 with HS-Tt. Baseline characteristics were similar across groups, with a mean age of 67.12 ± 0.60 years, 79.7% male, and 37.4% with diabetes. Across all types of troponins, the detection of periprocedural myocardial injury or infarction was much higher at D1 versus D0 (22.8% (429/1879) vs 8.9% (168/1879), respectively). While troponin types showed similar detection of periprocedural MI or injury at D0, HS-Tt was associated with a lower proportion of events at D1 (18.2% [223/1227]) compared with non-HS T (31.08% [92/296]) and HS-Ti (32% [114/356]) (p-value < 0.001), driven by a lower detection of major myocardial injury (12.9% (158/1227) vs. 26.0% (77/296) vs. 26.7% (95/356), respectively). The rates of type 4a MI were consistent across troponin types at D0 and D1. Conclusion Time of measure and type of troponin should be taken into account for the detection of periprocedural myocardial infarction and injury. Same-day discharge might lead to an underestimation of periprocedural complications in complex PCI. While there was heterogeneity across assays for the detection of myocardial injury, the detection of type 4a MI remained consistent.