Men develop larger infarct sizes than women after a myocardial infarction (MI), but the mechanism underlying this sex difference is unknown. Here, we demonstrated that blood neutrophil counts post-MI were higher in male than female mice. Castration-induced testosterone deficiency reduced blood neutrophil counts to the level in females and increased survival post-MI. These effects were mimicked by Osterix-directed ablation of the androgen receptor in bone marrow (BM). Mechanistically, androgens downregulated the leukocyte retention factor CXCL12 in BM stromal cells. Post-hoc analysis of clinical trial data showed that neutrophilia was greater in men than women after reperfusion of first-time ST-elevation MI, and tocilizumab, an interleukin-6 receptor inhibitor, reduced blood neutrophil counts and infarct size to a greater extent in men than women. Our work reveals a previously unknown mechanism connecting testosterone with neutrophilia and MI injury via BM and identifies the importance of considering sex when developing anti-inflammatory strategies to treat MI.
Dilated cardiomyopathy is characterized by left ventricular dilatation and dysfunction. Inflammation and adverse remodeling of the extracellular matrix may be involved in the pathogenesis. Statins reduce levels of low density lipoprotein cholesterol, but may also attenuate inflammation and affect matrix remodeling. We hypothesized that treatment with rosuvastatin would reduce or even reverse left ventricular remodeling in dilated cardiomyopathy. In this multicenter, randomized, double blind, placebo-controlled study, 71 patients were randomized to 10 mg of rosuvastatin or matching placebo. Physical examination, blood sampling, echocardiography and cardiac magnetic resonance imaging were performed at baseline and at six months’ follow-up. The pre-specified primary end point was the change in left ventricular ejection fraction from baseline to six months. Over all, left ventricular ejection fraction improved 5 percentage points over the duration of the study, but there was no difference in the change in left ventricular ejection fraction between patients allocated to rosuvastatin and those allocated to placebo. Whereas serum low density lipoprotein cholesterol concentration fell significantly in the treatment arm, rosuvastatin did not affect plasma or serum levels of a wide range of inflammatory variables, including C-reactive protein. The effect on markers of extracellular matrix remodeling was modest. Treatment with rosuvastatin does not improve left ventricular ejection fraction in patients with dilated cardiomyopathy. ClinicalTrials.gov NCT00505154
6 September 2023 in European Heart Journal - Cardiovascular Imaging
The non-invasive myocardial work index (MWI) has been validated in patients without aortic stenosis (AS). A thorough assessment of methodological limitations is warranted before this index can be applied to patients with AS. We simultaneously measured left ventricular pressure (LVP) by using a micromanometer-tipped catheter and obtained echocardiograms in 20 patients with severe AS. We estimated LVP curves and calculated pressure–strain loops using three different models: (i) the model validated in patients without AS; (ii) the same model, but with pressure at the aortic valve opening (AVO) adjusted to diastolic cuff pressure; and (iii) a new model based on the invasive measurements from patients with AS. Valvular events were determined by echocardiography. Peak LVP was estimated as the sum of the mean aortic transvalvular gradient and systolic cuff pressure. In same-beat comparisons between invasive and estimated LVP curves, Model 1 significantly overestimated early systolic pressure by 61 ± 5 mmHg at AVO compared with Models 2 and 3. However, the average correlation coefficients between estimated and invasive LVP traces were excellent for all models, and the overestimation had limited influence on MWI, with excellent correlation (r = 0.98, P < 0.001) and good agreement between the MWI calculated with estimated (all models) and invasive LVP. This study confirms the validity of the non-invasive MWI in patients with AS. The accuracy of estimated LVP curves improved when matching AVO to the diastolic pressure in the original model, mirroring that of the AS-specific model. This may sequentially enhance the accuracy of regional MWI assessment. Synopsis of the study design, key findings, and conclusions. Estimations and calculations based on Model 1 (red-dashed line) and Model 2 (blue-dashed line), where the pressure at AVO is adjusted to the diastolic cuff pressure and invasively measured LVP (grey line). AVC, aortic valve closure; AVO, aortic valve opening; MVC, mitral valve closure; MVO, mitral valve opening; LVP, left ventricular pressure; STE, speckle-tracking echocardiography.