An Hypothesis: Disproportion Between Cardiac Troponin and B-Type Natriuretic Peptide Levels-A High Risk and Poor Prognostic Biomarker in Patients With Fulminant Myocarditis?

In our clinical practice, we recently found some patients with severe fulminant myocarditis (FM) who showed persistently elevated cardiac troponin (cTn) levels and "seemingly normal" B-type natriuretic peptide (BNP) level, and who subsequently progressed to poor outcomes. Indeed, this sounds contrary to conventional wisdom, but it is not an accidental phenomenon. Fulminant myocarditis is a rapidly progressive disease associated with high mortality. Recent studies have shown that patients with FM are significantly more likely to require heart transplantation than those without FM. Prompt diagnosis of FM and the institution of advanced cardiac life support will save more lives. Cardiac troponin and BNP are widely used diagnostic markers. Cardiac troponin is a specific marker of cardiac injury and its level correlates with the severity of cardiac injury. However, plasma BNP has a dual identity; it is not only a marker of cardiac pressure/volume overload, but it is also a cardioprotective factor that provides effective neurohormonal compensation to maintain homeostasis. Similar to fulminant hepatitis (characterised by diffuse inflammation and massive parenchymal cell necrosis) sometimes showing disproportion between transaminase level and bilirubin level, the disproportion between cTn and BNP levels in FM seems to be consistent with its severe histopathological changes, including diffuse infiltration of the myocardium by inflammatory cells, as well as severe cardiomyocyte injury and necrosis. Moreover, in previous studies, a lower BNP level was found to be an adverse prognostic marker in end-stage heart failure. All these findings indicate that in patients with FM with a persistently high cTn level and ominous clinical presentation, a "seemingly normal" BNP level is not a friendly signal. We hypothesise that the combination of a persistently elevated cTn level and low BNP level in patients with FM indicates worse myocardial injury and poor prognosis.

Efficacy and safety of catheter-based renal denervation for heart failure with reduced ejection fraction: a systematic review and meta-analysis.

PURPOSE: To perform a comprehensive meta-analysis of all available evidence on the efficacy and safety of catheter-based renal denervation for heart failure with reduced ejection fraction. METHODS: We searched English and Chinese databases and calculated the weighted mean difference or standardized mean difference and 95% confidence intervals to estimate the efficacy and safety of renal denervation for heart failure. All relevant studies were screened and a meta-analysis was conducted using Review Manager 5.4. RESULTS: A total of 11 studies were identified for the meta-analysis. For the primary outcomes, the results showed that renal denervation significantly improved ejection fraction (weighted mean difference 6.42), left ventricular end-systolic diameter (weighted mean difference -3.95), left ventricular end-diastolic diameter (weighted mean difference -4.17) and left atrial diameter (weighted mean difference -4.09). For the secondary outcomes, renal denervation reduced the B-type natriuretic peptide level, heart rate, systolic blood pressure and diastolic blood pressure. However, further analysis revealed that renal denervation improved heart function but did not further reduce the heart rate and blood pressure compared with the control group. CONCLUSION: Treatment with renal denervation can significantly improve heart function and structure in patients with heart failure. In addition, the level of B-type natriuretic peptide can be reduced after renal denervation treatment. Renal denervation did not further reduce heart rate and blood pressure compared with the control group. Therefore, the treatment of heart failure with renal denervation is effective and safe.

Rosuvastatin Enhances Lymphangiogenesis after Myocardial Infarction by Regulating the miRNAs/Vascular Endothelial Growth Factor Receptor 3 (miRNAs/VEGFR3) Pathway.

BACKGROUND: Several clinical studies have suggested that the early administration of statins could reduce the risk of in-hospital mortality in acute myocardial infarction (AMI) patients. Recently, some studies have identified that stimulating lymphangiogenesis after AMI could improve cardiac function by reducing myocardial edema and inflammation. This study aimed to identify the effect of rosuvastatin on postinfarct lymphangiogenesis and to identify the underlying mechanism of this effect. METHOD: Myocardial infarction (MI) was induced by ligation of the left anterior descending coronary artery in mice orally administered rosuvastatin for 7 days. The changes in cardiac function, pathology, and lymphangiogenesis following MI were measured by echocardiography and immunostaining. EdU, Matrigel tube formation, and scratch wound assays were used to evaluate the effect of rosuvastatin on the proliferation, tube formation, and migration of the lymphatic endothelial cell line SVEC4-10. The expression of miR-107-3p, miR-491-5p, and VEGFR3 was measured by polymerase chain reaction (PCR) and Western blotting. A gain-of-function study was performed using miR-107-3p and miR-491-5p mimics. RESULTS: The rosuvastatin-treated mice had a significantly improved ejection fraction and increased lymphatic plexus density 7 days after MI. Rosuvastatin also reduced myocardial edema and inflammatory response after MI. We used a VEGFR3 inhibitor to partially reverse these effects. Rosuvastatin promoted the proliferation, migration, and tube formation of SVEC4-10 cells. PCR and Western blot analyses revealed that rosuvastatin intervention downregulated miR-107-3p and miR-491-5p and promoted VEGFR3 expression. The gain-of-function study showed that miR-107-3p and miR-491-5p could inhibit the proliferation, migration, and tube formation of SVEC4-10 cells. CONCLUSION: Rosuvastatin could improve heart function by promoting lymphangiogenesis after MI by regulating the miRNAs/VEGFR3 pathway.

Endothelial Microparticle-Mediated Transfer of microRNA-19b Inhibits the Function and Distribution of Lymphatic Vessels in Atherosclerotic Mice.

In recent years, the function of the lymphatic system in atherosclerosis has attracted attention due to its role in immune cell trafficking, cholesterol removal from the periphery, and regulation of the inflammatory response. However, knowledge of the mechanisms regulating lymphangiogenesis and lymphatic function in the pathogenesis of atherosclerosis is limited. Endothelial microparticles carrying circulating microRNA (miRNA)s are known to mediate cell-cell communication, and our previous research showed that miRNA-19b in EMPs (EMPmiR-19b) was significantly increased in circulation and atherosclerotic vessels, and this increase in EMPmiR-19b promoted atherosclerosis. The present study investigated whether atherogenic EMPmiR-19b influences pathological changes of the lymphatic system in atherosclerosis. We first verified increased miR-19b levels and loss of lymphatic system function in atherosclerotic mice. Atherogenic western diet-fed ApoE-/- mice were injected with phosphate-buffered saline, EMPs carrying control miRNA (EMPcontrol), or EMPmiR-19b intravenously. The function and distribution of the lymphatic system was assessed via confocal microscopy, Evans blue staining, and pathological analysis. The results showed that lymphatic system dysfunction existed in the early stage of atherosclerosis, and the observed pathological changes persisted at the later stage, companied by an increased microRNA-19b level. In ApoE-/- mice systemically treated with EMPmiR-19b, the distribution, transport function, and permeability of the lymphatic system were significantly inhibited. In vitro experiments showed that miRNA-19b may damage the lymphatic system by inhibiting lymphatic endothelial cell migration and tube formation, and a possible mechanism is the inhibition of transforming growth factor beta receptor type II (TGF-ßRII) expression in lymphatic endothelial cells by miRNA-19b. Together, our findings demonstrate that atherogenic EMPmiR-19b may destroy lymphatic system function in atherosclerotic mice by downregulating TGF-ßRII expression.

Therapeutic targets of rosuvastatin on heart failure and associated biological mechanisms: A study of network pharmacology and experimental validation.

To explore the potential targets underlying the effect of rosuvastatin on heart failure (HF) by utilizing a network pharmacology approach and experiments to identify the results. PharmMapper and other databases were mined for information relevant to the prediction of rosuvastatin targets and HF-related targets. Then, the rosuvastatin-HF target gene networks were created in Cytoscape software. Eventually, the targets and enriched pathways were examined by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Furthermore, we constructed an HF animal model and used rosuvastatin to treat them, identifying the changes in heart function and related protein expression. We further used different cells to explore the mechanisms of rosuvastatin. Thirty-five intersection targets indicated the therapeutic targets linked to HF. GO analysis showed that 481 biological processes, 4 cellular components and 23 molecular functions were identified. KEGG analysis showed 13 significant treatment pathways. In animal experiments, rosuvastatin significantly improved the cardiac function of post-myocardial infarction mice and prevented the development of HF after myocardial infarction by inhibiting IL-1Β expression. Cell experiments showed that rosuvastatin could reduce the expression of IL-1B in HUVEC and THP-1 cells. The therapeutic mechanism of rosuvastatin against HF may be closely related to the inhibition of the expression of apoptosis-related proteins, inflammatory factors, and fibrosis-related genes. However, IL-1Β is one of the most important target genes.