Bøtker, Hans Erik

Abstract A substantial number of chronic coronary syndrome (CCS) patients undergoing percutaneous coronary intervention (PCI) experience periprocedural myocardial injury or infarction. Accurate diagnosis of these PCI-related complications is required to guide further management given that their occurrence may be associated with increased risk of major adverse cardiac events (MACE). Due to lack of scientific data, the cut-off thresholds of post-PCI cardiac troponin (cTn) elevation used for defining periprocedural myocardial injury and infarction, have been selected based on expert consensus opinions, and their prognostic relevance remains unclear. In this Consensus Document from the ESC Working Group on Cellular Biology of the Heart and European Association of Percutaneous Cardiovascular Interventions (EAPCI), we recommend, whenever possible, the measurement of baseline (pre-PCI) cTn and post-PCI cTn values in all CCS patients undergoing PCI. We confirm the prognostic relevance of the post-PCI cTn elevation >5× 99th percentile URL threshold used to define type 4a myocardial infarction (MI). In the absence of periprocedural angiographic flow-limiting complications or electrocardiogram (ECG) and imaging evidence of new myocardial ischaemia, we propose the same post-PCI cTn cut-off threshold (>5× 99th percentile URL) be used to define prognostically relevant ‘major’ periprocedural myocardial injury. As both type 4a MI and major periprocedural myocardial injury are strong independent predictors of all-cause mortality at 1 year post-PCI, they may be used as quality metrics and surrogate endpoints for clinical trials. Further research is needed to evaluate treatment strategies for reducing the risk of major periprocedural myocardial injury, type 4a MI, and MACE in CCS patients undergoing PCI.

Objectives: We investigated the correlation between left ventricular global and regional longitudinal systolic strain (GLS and LRS) and coronary flow reserve (CFR) assessed by transthoracic echocardiography (TTE) in patients with a recent acute myocardial infarction (AMI). Furthermore, we investigated if LRS and GLS imaging is superior to conventional measures of left ventricle (LV) function. Methods: In a consecutive population of first time AMI patients, who underwent successful revascularization, we performed comprehensive TTE. GLS and LRS were obtained from the three standard apical views. Assessment of CFR by TTE was performed in a modified apical view using color Doppler guidance. Results: The study population consisted of 183 patients (51 females) with a median age of 63 [54;70] years. Eighty‐nine (49%) patients had a non‐ST elevation myocardial infarction and 94 (51%) patients had a ST elevation myocardial infarction. The GLS was −15.2 [−19.3;−10.1]% in the total population of 183 patients. Total wall motion score index (WMSI) in the population was 1.19 [1;1.5]. Eighty‐five patients suffered from culprit lesion in left anterior descending artery (LAD). The CFR in these patients was 1.86 [1.36;2.35] and the GLS was −14.3 [−18.9; −9.8]%. A significant difference was observed in the LRS in LAD territory in culprit LAD infarction patients with a CFR ≤ 2 (−9.6 [−13.77;−6.44]) compared with the LRS in LAD territory in culprit LAD infarction patients with a CFR > 2 (−19.33 [−21.1;−16.5]), P < 0.0001. We found no significant difference between WMSI in LAD territory in culprit LAD infarction patients with a CFR ≤ 2 (1.56 [1.06;2.23]) compared with WMSI in LAD territory in culprit LAD infarction patients with a CFR > 2 (1.37 [1.03;2.11]); P = 0.18. The same pattern was observed in both circumflex coronary artery (CX) and right coronary artery (RCA) territories. In the total population, we found a strong correlation between CFR and GLS (r = −0.85, P < 0.0001). This was also seen in the multivariate regression model adjusting for possible confounders including WMSI (P < 0.001). Conclusion: In this study, we have shown a close association between myocardial deformation in patients with a recent AMI and the degree of diminished microcirculation. We found that both GLS and LRS correlated with CFR. We conclude that GLS and LRS are significantly better tools to assess impaired CFR and LV function after a recent AMI, than conventional echocardiographic measurements.