SARS-CoV-2-Induced Multisystem Inflammatory Syndrome in a Young Adult: Case Report

We describe a case of a previous healthy 20-year-old male athlete who presented with an atypical clinical profile with multiorgan involvement within five weeks after confirmed SARS-CoV-2 infection, suggestive for multisystem inflammatory syndrome (MIS); MIS is a rare, potentially life-threatening complication associated with SARS-CoV-2. MIS shares similar clinical features compatible with several overlapping lifethreatening hyperinflammatory syndromes, such as incomplete Kawasaki Disease (KD) and toxic shock syndrome (TSS) associated to a cytokine storm suggestive of a macrophage activation syndrome (MAS) without fulfilling the criteria for hemophagocytic lymphohistiocytosis (HLH), that may create a great challenge to distinguish between them. MIS should promptly be considered and treated, as uncontrolled MIS has a high mortality.In MIS cardiac involvement, heart failure may present as an additional problem, especially because volume loading is advised in accordance with proposed therapy. Carefully monitoring of the respiratory and cardiac status in response of resuscitation is therefore warranted.

SARS-CoV-2-induced Multisystem Inflammatory Syndrome in a Young Adult

We describe a case of a previous healthy 20-year-old male athlete who presented with an atypical clinical profile with multiorgan involvement five weeks after confirmed SARS-CoV-2 infection, suggestive for multisystem inflammatory syndrome (MIS). MIS is a rare, potentially life-threatening complication associated with SARS-CoV-2 and shares several similar clinical features with overlapping hyperinflammatory syndromes that may create a great challenge to distinguish between them. MIS should promptly be considered and treated, as uncontrolled MIS has a high mortality. In MIS cardiac involvement, heart failure may present as an additional problem, especially because volume loading is advised in accordance with proposed therapy. Carefully monitoring of the respiratory and cardiac status in response of resuscitation is therefore warranted.

The use of pulse pressure variation for predicting impairment of microcirculatory blood flow

Dynamic parameters of preload have been widely recommended to guide fluid therapy based on the principle of fluid responsiveness and with regard to cardiac output. An equally important aspect is however to also avoid volume-overload. This accounts particularly when capillary leakage is present and volume-overload will promote impairment of microcirculatory blood flow. The aim of this study was to evaluate, whether an impairment of intestinal microcirculation caused by volume-load potentially can be predicted using pulse pressure variation in an experimental model of ischemia/reperfusion injury. The study was designed as a prospective explorative large animal pilot study. The study was performed in 8 anesthetized domestic pigs (German landrace). Ischemia/reperfusion was induced during aortic surgery. 6 h after ischemia/reperfusion-injury measurements were performed during 4 consecutive volume-loading-steps, each consisting of 6 ml kg−1 bodyweight−1. Mean microcirculatory blood flow (mean Flux) of the ileum was measured using direct laser-speckle-contrast-imaging. Receiver operating characteristic analysis was performed to determine the ability of pulse pressure variation to predict a decrease in microcirculation. A reduction of ≥ 10% mean Flux was considered a relevant decrease. After ischemia–reperfusion, volume-loading-steps led to a significant increase of cardiac output as well as mean arterial pressure, while pulse pressure variation and mean Flux were significantly reduced (Pairwise comparison ischemia/reperfusion-injury vs. volume loading step no. 4): cardiac output (l min−1) 1.68 (1.02–2.35) versus 2.84 (2.15–3.53), p = 0.002, mean arterial pressure (mmHg) 29.89 (21.65–38.12) versus 52.34 (43.55–61.14), p < 0.001, pulse pressure variation (%) 24.84 (17.45–32.22) versus 9.59 (1.68–17.49), p = 0.004, mean Flux (p.u.) 414.95 (295.18–534.72) versus 327.21 (206.95–447.48), p = 0.006. Receiver operating characteristic analysis revealed an area under the curve of 0.88 (CI 95% 0.73–1.00; p value < 0.001) for pulse pressure variation for predicting a decrease of microcirculatory blood flow. The results of our study show that pulse pressure variation does have the potential to predict decreases of intestinal microcirculatory blood flow due to volume-load after ischemia/reperfusion-injury. This should encourage further translational research and might help to prevent microcirculatory impairment due to excessive fluid resuscitation and to guide fluid therapy in the future.

Sustained Improvement in Diastolic Reserve Following Percutaneous Pericardiotomy in a Porcine Model of Heart Failure With Preserved Ejection Fraction

Background: Heart failure with preserved ejection fraction is increasing in prevalence, but few effective treatments are available. Elevated left ventricular (LV) diastolic filling pressures represent a key therapeutic target. Pericardial restraint contributes to elevated LV end-diastolic pressure, and acute studies have shown that pericardiotomy attenuates the rise in LV end-diastolic pressure with volume loading. However, whether these acute effects are sustained chronically remains unknown. Methods: Minimally invasive pericardiotomy was performed percutaneously using a novel device in a porcine model of heart failure with preserved ejection fraction. Hemodynamics were assessed at baseline and following volume loading with pericardium intact, acutely following pericardiotomy, and then again chronically after 4 weeks. Cardiac structure was assessed by magnetic resonance imaging. Results: The increase in LV end-diastolic pressure with volume loading was mitigated by 41% (95% CI, 27%–45%, P <0.0001; ΔLV end-diastolic pressure reduced from +9±3 mm Hg to +5±3 mm Hg, P =0.0003, 95% CI, −2.2 to −5.5). The effect was sustained at 4 weeks (+5±2 mm Hg, P =0.28 versus acute). There was no statistically significant effect of pericardiotomy on ventricular remodeling compared with age-matched controls. None of the animals developed hemodynamic or pathological indicators of pericardial constriction or frank systolic dysfunction. Conclusions: The acute hemodynamic benefits of pericardiotomy are sustained for at least 4 weeks in a swine model of heart failure with preserved ejection fraction, without excessive chamber remodeling, pericarditis, or clinically significant systolic dysfunction. These data support trials evaluating minimally invasive pericardiotomy as a novel treatment for heart failure with preserved ejection fraction in humans.

Safety and effects of volume loading during transesophageal echocardiography in the pre-procedural work-up for left atrial appendage closure

Background In patients undergoing left atrial appendage (LAA) closure, an accurate sizing of the LAA is key to optimize device sizing, procedural success and reduce complications. Previous studies have shown that intraprocedural volume loading increases LAA dimensions and improves device sizing. However, the safety and effects on LAA and device sizing of administering a fluid bolus during pre-procedural transesophageal echocardiography (TEE) are unknown. The aim of this study was to determine the safety and impact on LAA dimensions and device sizing of an intravenous (IV) fluid bolus administered during TEE in the setting of the pre-procedural work-up for LAA closure. Methods The study included a total of 72 patients who underwent TEE to assess suitability for LAAC and received a 500 ml IV bolus of normal saline. The LAA landing zone (LZ) and depth were measured by TEE before and after volume loading, and these measurements were used to predict the device size implanted during a subsequent percutaneous LAAC procedure. Results There were no complications associated with volume loading. The baseline mean LZ was 19.6 ± 3.6 mm at 90o, and 20.2 ± 4.1 mm at 135o. Following fluid bolus, the maximum diameter increased 1.5 ± 1.0 mm at 90o (p<0.001), and 1.3 ± 1.0 mm at 135o (p<0.001). The baseline mean depth of the LAA was 26.5 ± 5.5 mm at 90o, and 23.9 ± 5.8 mm at 135o. After fluid bolus, the mean depth increased by 1.5 ± 1.8 mm (p<0.001) and 1.6 ± 2.0 (p<0.001), at 90o and 135o, respectively. Sizing based on post-bolus measurements of the LZ significantly improved the agreement with the final device size selection during the procedure in 71.0% of cases (vs. 42.0% with pre-bolus measurements). Conclusions Volume loading during ambulatory TEE as part of the pre-procedural work-up of LAAC is safe and significantly increases LAA dimensions. This strategy may become the new standard, particularly in centers performing LAAC with no TEE guidance, as it improves LAA sizing and more accurately predicts the final device size.

Stimulus-specific functional remodeling of the left ventricle in endurance and resistance-trained men

Training-specific functional remodeling of the LV in response to different loading conditions has been recently suggested, but not experimentally tested in the same group of individuals. Our data provide novel evidence of a dichotomous, training-specific LV adaptive response to hemodynamic pressure or volume loading.

Three-dimensional right ventricular shape and strain in congenital heart disease patients with right ventricular chronic volume loading

Aims Right ventricular (RV) function assessment is crucial in congenital heart disease patients, especially in atrial septal defect (ASD) and repaired Tetralogy of Fallot (TOF) patients with pulmonary regurgitation (PR). In this study, we aimed to analyse both 3D RV shape and deformation to better characterize RV function in ASD and TOF-PR. Methods and results We prospectively included 110 patients (≥16 years old) into this case–control study: 27 ASD patients, 28 with TOF, and 55 sex- and age-matched healthy controls. Endocardial tracking was performed on 3D transthoracic RV echocardiographic sequences and output RV meshes were post-processed to extract local curvature and deformation. Differences in shape and deformation patterns between subgroups were quantified both globally and locally. Curvature highlights differences in RV shape between controls and patients while ASD and TOF-PR patients are similar. Conversely, strain highlights differences between controls and TOF-PR patients while ASD and controls are similar [global area strain: −31.5 ± 5.8% (controls), −34.1 ± 7.9% (ASD), −24.8 ± 5.7% (TOF-PR), P &lt; 0.001, similar significance for longitudinal and circumferential strains]. The regional and local analysis highlighted differences in particular in the RV free wall and the apical septum. Conclusion Chronic RV volume loading results in similar RV shape remodelling in both ASD and TOF patients while strain analysis demonstrated that RV strain is only reduced in the TOF group. This suggests a fundamentally different RV remodelling process between both conditions.

Effects of Different Pre-processing Methods on Dry Anaerobic Fermentation of Sugarcane Leaves and Pig Manure

Using agricultural wastes for anaerobic fermentation to produce biogas can not only realize the resource utilization of the wastes, but also prevent the environmental issues caused by straw burning. Sugarcane leaves contain waxy layer, which will cause problems such as difficulty in degradation, long-time fermentation and low biogas production. This paper studies the effects on three pre-processing methods of adding rush rot agent, natural retting for 7 days and water moisture for 24 hours of dry anaerobic fermentation of sugarcane leaves and pig manure. The results show that natural retting for 7 days has the advantage of daily biogas production when the fermentation period is less than 20 days, but this method is not obviously different from that of water moisture for 24 hours. When taking total biogas production volume and volume loading rate as the indicators, water moisture for 24 hours is the best pre-processing method for dry anaerobic fermentation of sugarcane leaves and pig manure when the fermentation period is more than 20 days.

Effect of Volume Loading Rate and C/N on Ship Domestic Sewage Treatment by Two Membrane Bioreactors

Design of ship sewage treatment systems that not only satisfy the use of small space on board but also meets International Maritime Organisation (IMO) latest emission standards is still a challenging problem for ship industry. This study provides a comparative disquisition between two different MBR reactors i.e, air-lift multilevel circulation membrane reactor (AMCMBR) and anaerobic/anoxic/aerobic membrane reactor (AOA-MBR) for domestic sewage treatment. The influence of pollutants volume loading rate (VLR) and C/N on effluent chemical oxygen demand (COD), ammonium nitrogen (NH4+-N) and TN for marine domestic sewage was analyzed. The results revealed that AMCMBR showed better removal efficiencies for COD and TN than AOA-MBR. The volume of AMCMBR was only half of the AOA-MBR. In addition, high average value of mixed liquor volatile suspended solids (MLVSS)/mixed liquid suspended solids (MLSS) (i.e. 0.75) of AMCMBR indicated high biomass and good pollutants removal achieved by this reactor. An interesting phenomenon was found in the study regarding Urease activity for the two reactors. Urease activity for AMCMBR in different working conditions all exceeded AOA-MBR and there exist no clear difference of NR activities between AMCMBR and AOA-MBR except for low C/N ratio (i.e. 6 and 4). This phenomenon proved that AMCMBR has a greater performance for treating ship domestic wastewater.