Identification of Periprocedural Myocardial Infarction Using a High-Sensitivity Troponin I Assay in Patients Who Underwent Transcatheter Aortic Valve Implantation

Periprocedural myocardial infarction (MI), a rare complication after transcatheter aortic valve implantation (TAVI), is associated with worse outcome. According to the Valve Academic Research Consortium (VARC-2), MI is defined by an increase in cardiac troponin (cTn) and creatine kinase MB (CK-MB) levels; however, many patients show periprocedurally elevated cTn without clinical evidence of MI. The aims of this study were to establish reference values of cardiac troponin I measured with a high-sensitivity assay (hs-cTnI) and to assess the periprocedural diagnostic value of this biomarker in patients who underwent TAVI. Hs-cTnI and CK-MB levels were assessed before and up to 3 days after transfemoral (TF) or transapical (TA) TAVI in 515 patients. A high proportion (61.2%) of patients had elevated hs-cTnI at baseline. According to VARC-2 criteria, almost all TA-patients (99.5%) showed an MI based on hs-cTnI compared with 4.2% based on CK-MB. In TF-patients, 81.1% had an MI based on hs-cTnI compared with 9.0% based on CK-MB. Only 10 patients (2%), however, had a type 1 MI. The ninety-ninth percentile for hs-cTnI was 285 ng/L in the TAVI cohort. After applying a TAVI-specific cutoff the frequency of MI was lower and more realistic (TF: 5% vs 81.1%; p <0.001; TA: 22.2% vs 99.5%; p <0.001). In conclusion, the VARC-2 definition leads to an overestimation of periprocedural MI. Our new TAVI-specific reference values yield a more realistic estimation of the myocardial ischemic risk. hs-cTnI, however, does not seem to be the biomarker of choice for MI detection in this setting.