Search

Background We aimed to identify patients with subphenotypes of postacute coronary syndrome (ACS) using repeated measurements of high‐sensitivity cardiac troponin T, N‐terminal pro‐B‐type natriuretic peptide, high‐sensitivity C‐reactive protein, and growth differentiation factor 15 in the year after the index admission, and to investigate their association with long‐term mortality risk. Methods and Results BIOMArCS (BIOMarker Study to Identify the Acute Risk of a Coronary Syndrome) was an observational study of patients with ACS, who underwent high‐frequency blood sampling for 1 year. Biomarkers were measured in a median of 16 repeated samples per individual. Cluster analysis was performed to identify biomarker‐based subphenotypes in 723 patients without a repeat ACS in the first year. Patients with a repeat ACS (N=36) were considered a separate cluster. Differences in all‐cause death were evaluated using accelerated failure time models (median follow‐up, 9.1 years; 141 deaths). Three biomarker‐based clusters were identified: cluster 1 showed low and stable biomarker concentrations, cluster 2 had elevated concentrations that subsequently decreased, and cluster 3 showed persistently elevated concentrations. The temporal biomarker patterns of patients in cluster 3 were similar to those with a repeat ACS during the first year. Clusters 1 and 2 had a similar and favorable long‐term mortality risk. Cluster 3 had the highest mortality risk. The adjusted survival time ratio was 0.64 (95% CI, 0.44–0.93; P=0.018) compared with cluster 1, and 0.71 (95% CI, 0.39–1.32; P=0.281) compared with patients with a repeat ACS. Conclusions Patients with subphenotypes of post‐ACS with different all‐cause mortality risks during long‐term follow‐up can be identified on the basis of repeatedly measured cardiovascular biomarkers. Patients with persistently elevated biomarkers have the worst outcomes, regardless of whether they experienced a repeat ACS in the first year.

Background Cardiac troponin T (cTnT) is seen in many other conditions besides myocardial infarction, and recent studies demonstrated distinct forms of cTnT. At present, the in vivo formation of these different cTnT forms is incompletely understood. We therefore performed a study on the composition of cTnT during the course of myocardial infarction, including coronary venous system sampling, close to its site of release. Methods and Results Baseline samples were obtained from multiple coronary venous system locations, and a peripheral artery and vein in 71 non–ST‐segment–elevation myocardial infarction patients. Additionally, peripheral blood was drawn at 6‐ and 12‐hours postcatheterization. cTnT concentrations were measured using the high‐sensitivity‐cTnT immunoassay. The cTnT composition was determined via gel filtration chromatography and Western blotting in an early and late presenting patient. High‐sensitivity ‐cTnT concentrations were 28% higher in the coronary venous system than peripherally (n=71, P

Background Regular exercise training is an important factor in prevention of myocardial infarction (MI). However, little is known whether exercise engagement prior to MI is related to the magnitude of post-MI cardiac biomarker concentrations and clinical outcomes.Objectives We tested the hypothesis that exercise engagement in the week prior MI is related to lower cardiac biomarker concentrations following ST-elevated MI (STEMI).Methods We recruited hospitalised STEMI patients and assessed the amount of exercise engagement in the 7 days preceding MI onset using a validated questionnaire. Patients were classified as ‘exercise’ if they performed any vigorous exercise in the week prior MI, or as ‘control’ if they did not. Post-MI peak concentrations of high-sensitive cardiac troponin T (peak-hs-cTnT) and creatine kinase (peak-CK) were examined. We also explored whether exercise engagement prior MI is related to the clinical course (duration of hospitalisation and incidence of in-hospital, 30-day and 6-month major adverse cardiac events (reinfarction, target vessel revascularisation, cardiogenic shock or death)).Results In total, 98 STEMI patients were included, of which 16% (n=16) was classified as ‘exercise’, and 84% (n=82) as ‘control’. Post-MI peak-hs-cTnT and peak-CK concentrations were lower in the exercise group (941 (645–2925) ng/mL; 477 (346–1402) U/L, respectively) compared with controls (3136 (1553–4969) ng/mL, p=0.010; 1055 (596–2019) U/L, p=0.016, respectively). During follow-up, no significant differences were found between both groups.Conclusion Engagement in exercise is associated with lower cardiac biomarker peak concentrations following STEMI. These data could provide further support for the cardiovascular health benefits of exercise training.