The actively secreted plasma extracellular vesicle troponin (ASPECT) study: circulating troponin in extracellular vesicles across cardiovascular disease cohorts

Figures

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  Fig. 1. A. Extracellular Vesicle (EV) / Non- Extracellular Vesicle (NEV) Troponin ratio B. EV/ Plasma Troponin ratio across different physiological and pathological groups, including Endurance Athletes, Healthy Controls, Pre- and Post-Exercise, Hypertrophic Cardiomyopathy (HCM), Chronic Heart Failure (CHF), Acute Heart Failure (AHF), Type 1 Myocardial Infarction (T1MI), Type 2 Myocardial Infarction (T2MI), and End-Stage Renal Disease (ESKD). EV indicated by Extracellular Vesicle Fraction, and NEV indicated by Non-Extracellular Vesicle Fraction. Box plots show median and interquartile range; individual data points are overlaid. ****p < 0.0001where p is calculated using Kruskal-Wallis test using GraphPad Prism. For the entire pairwise comparisons using Dunn’s test (after adjustment) please refer Supplementary Fig. 4 for EV/NEV (A) and EV/Plasma (B) comparison between the different groups. Note: EV/Plasma ratios (Panel B) could not be calculated for Obs HCM and Non-Obs HCM cohorts due to limited sample volumes precluding measurement of unprocessed plasma troponin in these groups

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  Fig. 2. Correlation analysis of EV, NEV, and Plasma troponin with clinical biomarkers. (A) Spearman correlation matrix showing pairwise associations among Plasma, EV, and NEV troponin concentrations, NT-proBNP, creatinine, and left ventricular ejection fraction (EF). Values represent Spearman’s ρ; color intensity reflects correlation strength. NEV troponin was strongly correlated with Plasma troponin (ρ = 0.96), while EV troponin showed moderate correlations with both Plasma (ρ = 0.63) and NEV (ρ = 0.65) troponin. Notably, neither EV nor NEV troponin correlated with NT-proBNP, creatinine, or EF. (B) EV versus Plasma troponin (Spearman ρ = 0.63, p < 0.0001, n = 229). (C) NEV versus Plasma troponin (Spearman ρ = 0.96, p < 0.0001, n = 230). (D) NEV versus EV troponin (Spearman ρ = 0.65, p < 0.0001, n = 286). All scatter plots display log₁₀-transformed values with linear regression lines. The strong NEV-Plasma correlation indicates that non-vesicular troponin comprises the majority of circulating troponin, while the moderate EV-Plasma and EV-NEV correlations suggest that vesicular troponin release operates partly independently of passive troponin release mechanisms. ****p < 0.0001

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  Fig. 3. Circulating troponin secretion modes based on EV/NEV troponin ratio & plasma troponin levels. (A) EV (Extracellular Vesicle) / NEV (Non-Extracellular Vesicle) Troponin ratio represented as percentage across different physiological and pathological groups, including Endurance Athletes (n = 22), Healthy Controls (n = 25), Pre-Exercise (n = 28), Post-Exercise (n = 28), Obstructive Hypertrophic Cardiomyopathy (Obs HCM, n = 25), Non-Obstructive Hypertrophic Cardiomyopathy (Non-Obs HCM, n = 24), Chronic Heart Failure (CHF, n = 24), Acute Heart Failure (AHF, n = 31), End-Stage Kidney Disease (ESKD, n = 26), Type 2 Myocardial Infarction (T2MI, n = 29), and Type 1 Myocardial Infarction (T1MI, n = 28). High EV/NEV ratios in athletes, controls, and exercise cohorts indicate physiological active EV secretion, whereas chronic stress-associated conditions (Obs HCM, Non-Obs HCM, CHF) show moderate EV-associated troponin release. Myocardial strain (AHF) exhibits intermediate EV involvement, while necrosis/accumulation-driven conditions (ESKD, T2MI, T1MI) show minimal EV-associated troponin. (B) Plasma troponin levels (ng/L) highlight differences in release mechanisms across groups with available…