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861.
Respiratory parameters and sound were recorded during professional flute playing in order to assess what physiological processes were associated with the control of sound production that results in 'breath support' which in turn is associated with high quality playing. Four standing young professional flautists played flute excerpts with and without breath support. Recordings included optoelectronic plethysmographic measurements of chest wall volume (V(cw)) and its compartments, surface electromyography of the scalene, lateral abdominal, rectus abdominus, parasternal and sternocleidomastoid muscles, mouth pressure, and sound. Flow was estimated from differentiating V(cw) during playing. Results showed that flute support entails antagonistic contraction of non-diaphragmatic inspiratory muscles that tends to hold the rib cage at higher lung volume. This relieves the expiratory muscles from the task of producing the right mouth pressure, especially at the end of the phrases, so they can contribute more to the finer control of mouth pressure modulations required for high quality playing.  相似文献   
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865.

Aims

For patients with heart failure (HF) and iron deficiency (ID), randomized trials suggest that intravenous (IV) iron reduces hospitalizations for heart failure (HHF), but uncertainty exists about the effects in subgroups and the impact on mortality. We conducted a meta-analysis of randomized trials investigating the effect of IV iron on clinical outcomes in patients with HF.

Methods and results

We identified randomized trials published between 1 January 2000 and 5 November 2022 investigating the effect of IV iron versus standard care/placebo in patients with HF and ID in any clinical setting, regardless of HF phenotype. Trials of oral iron or not in English were not included. The main outcomes of interest were a composite of HHF and cardiovascular death (CVD), on HHF alone and on cardiovascular and all-cause mortality. Ten trials were identified with 3373 participants, of whom 1759 were assigned to IV iron. IV iron reduced the composite of recurrent HHF and CVD (rate ratio 0.75, 95% confidence interval [CI] 0.61–0.93; p < 0.01) and first HHF or CVD (odds ratio [OR] 0.72, 95% CI 0.53–0.99; p = 0.04). Effects on cardiovascular (OR 0.86, 95% CI 0.70–1.05; p = 0.14) and all-cause mortality (OR 0.93, 95% CI 0.78–1.12; p = 0.47) were inconclusive. Results were similar in analyses confined to the first year of follow-up, which was less disrupted by the COVID-19 pandemic. Subgroup analyses found little evidence of heterogeneity for the effect on the primary endpoint, although patients with transferrin saturation <20% (OR 0.67, 95% CI 0.49–0.92) may have benefited more than those with values ≥20% (OR 0.99, 95% CI 0.74–1.30) (heterogeneity p = 0.07).

Conclusion

In patients with HF and ID, this meta-analysis suggests that IV iron reduces the risk of HHF but whether this is associated with a reduction in cardiovascular or all-cause mortality remains inconclusive.  相似文献   
866.
Accessory spleen rupture can induce acute abdominal bleeding following minimal trauma or by atraumatic mechanisms. Spleen rupture is more frequent in pediatric patients and those affected by hematological diseases. We described the case of a 59-year-old male patient affected by hereditary spherocytosis referred to the emergency department for abdominal left side pain. An early ultrasound performed in the emergency department allowed to diagnosed hemoperitoneum by spontaneous bleeding of hypertrophic accessory spleen. Although abdomen computed tomography is the diagnostic method of choice, ultrasound can early detect sign of emoperitoneum in the emergency setting in case of hemodinamically unstable patient.  相似文献   
867.

Aim

An echocardiographic algorithm derived by machine learning (e′VM) characterizes pre-clinical individuals with different cardiac structure and function, biomarkers, and long-term risk of heart failure (HF). Our aim was the external validation of the e′VM algorithm and to explore whether it may identify subgroups who benefit from spironolactone.

Methods and results

The HOMAGE (Heart OMics in AGEing) trial enrolled participants at high risk of developing HF randomly assigned to spironolactone or placebo over 9 months. The e′VM algorithm was applied to 416 participants (mean age 74 ± 7 years, 25% women) with available echocardiographic variables (i.e. e′ mean, left ventricular end-diastolic volume and mass indexed by body surface area [LVMi]). The effects of spironolactone on changes in echocardiographic and biomarker variables were assessed across e′VM phenotypes. A majority (>80%) had either a ‘diastolic changes’ (D), or ‘diastolic changes with structural remodelling’ (D/S) phenotype. The D/S phenotype had the highest LVMi, left atrial volume, E/e', natriuretic peptide and troponin levels (all p < 0.05). Spironolactone significantly reduced E/e' and B-type natriuretic peptide (BNP) levels in the D/S phenotype (p < 0.01), but not in other phenotypes (p > 0.10; pinteraction <0.05 for both). These interactions were not observed when considering guideline-recommended echocardiographic structural and functional abnormalities. The magnitude of effects of spironolactone on LVMi, left atrial volume and a type I collagen marker was numerically higher in the D/S phenotype than the D phenotype but the interaction test did not reach significance.

Conclusions

In the HOMAGE trial, the e′VM algorithm identified echocardiographic phenotypes with distinct responses to spironolactone as assessed by changes in E/e' and BNP.  相似文献   
868.
The right bundle branch (RBB), due to its endocardial course, is susceptible to traumatic block caused by “bumping” during right-heart catheterization. In the era of cardiac electrophysiology, catheter-induced RBB block (CI-RBBB) has become a common phenomenon observed during electrophysiological studies and catheter ablation procedures. While typically transient, it may persist for the entire procedure time. Compared to pre-existing RBBB, the transient nature of CI-RBBB allows for comparative analysis relative to the baseline rhythm. Furthermore, unlike functional RBBB, it occurs at similar heart rates, making the comparison of conduction intervals more reliable. While CI-RBBB can provide valuable diagnostic information in various conditions, it is often overlooked by cardiac electrophysiologists. Though it is usually a benign and self-limiting conduction defect, it may occasionally lead to diagnostic difficulties, pitfalls, or undesired consequences. Avoidance of CI-RBBB is advised in the presence of baseline complete left bundle branch block and when approaching arrhythmic substrates linked to the right His-Purkinje-System, such as fasciculo-ventricular pathways, bundle branch reentry, and right-Purkinje focal ventricular arrhythmias. This article aims to provide a comprehensive practical review of the electrophysiological phenomena related to CI-RBBB and its impact on the intrinsic conduction system and various arrhythmic substrates.  相似文献   
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