RV longitudinal deformation correlates with myocardial fibrosis in patients with end-stage heart failure

Objectives This study was performed to determine the accuracy of right ventricular (RV) longitudinal strain (LS) in predicting myocardial fibrosis in patients with severe heart failure (HF) undergoing heart transplantation. Background RVLS plays a key role in the evaluation of its systolic performance and clinical outcome in patients with refractory HF. Methods We studied 27 patients with severe systolic HF (ejection fraction 25% and New York Heart Association functional class III to IV, despite full medical therapy and cardiac resynchronization therapy) using echocardiography before heart transplantation. RV free wall LS, right atrial LS, sphericity index (SI), and tricuspid annular plane systolic excursion (TAPSE) were all measured. Upon removal of the heart, from the myocardial histologic analysis, the ratio of the fibrotic to the total sample area determined the extent of fibrosis (%). Results RV myocardial fibrosis correlated with RV free wall LS (r = 0.80; p < 0.0001), SI (r = 0.42; p = 0.01) and VO max (r = -0.41; p = 0.03), with a poor correlation with TAPSE (r = -0.34; p = 0.05) and right atrial LS (r = -0.37; p = 0.03). Stepwise multivariate analysis showed that RV free wall LS (β = 0.701, p < 0.0001) was independently associated with RV fibrosis (overall model R= 0.64, p < 0.0001). RV free wall LS was the main determinant of myocardial fibrosis. In the subgroup of patients with severe RV fibrosis, RV free wall LS had the highest diagnostic accuracy for detecting severe myocardial fibrosis (area under the curve = 0.87; 95% confidence interval: 0.80 to 0.94). Conclusions In late-stage HF patients, the right ventricle is enlarged, with reduced systolic function due to significant myocardial fibrosis. RV free wall myocardial deformation is the most accurate functional measure that correlates with the extent of RV myocardial fibrosis and functional capacity

A multidisciplinary approach for the emergency care of patients with left ventricular assist devices: A practical guide

The use of a left ventricular assist device (LVAD) as a bridge-to-transplantation or destination therapy to support cardiac function in patients with end-stage heart failure (HF) is increasing in all developed countries. However, the expertise needed to implant and manage patients referred for LVAD treatment is limited to a few reference centers, which are often located far from the patient's home. Although patients undergoing LVAD implantation should be permanently referred to the LVAD center for the management and follow-up of the device also after implantation, they would refer to the local healthcare service for routine assistance and urgent health issues related to the device or generic devices. Therefore, every clinician, from a bigger to a smaller center, should be prepared to manage LVAD carriers and the possible risks associated with LVAD management. Particularly, emergency treatment of patients with LVAD differs slightly from conventional emergency protocols and requires specific knowledge and a multidisciplinary approach to avoid ineffective treatment or dangerous consequences. This review aims to provide a standard protocol for managing emergency and urgency in patients with LVAD, elucidating the role of each healthcare professional and emphasizing the importance of collaboration between the emergency department, in-hospital ward, and LVAD reference center, as well as algorithms designed to ensure timely, adequate, and effective treatment to patients with LVAD. Copyright © 2022 Cameli, Pastore, Mandoli, Landra, Lisi, Cavigli, D'Ascenzi, Focardi, Carrucola, Dokollari, Bisleri, Tsioulpas, Bernazzali, Maccherini and Valente

Severe feed restriction increases permeability of mammary gland cell tight junctions and reduces ethanol stability of milk.

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Role of minerals on casein micelle stability of bovine milk

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Changes in physical properties of bovine milk from the colostrum period to early lactation

The aim of this study was to analyze individual cows' samples from the colostrum, postcolostrum, and early lactation periods to investigate how milk composition, physical properties, stability, and suitability for processing change throughout this period. Attention was paid to the first week postpartum in which the composition of bovine mammary secretion can change markedly. Properties including pH, titratable acidity, ethanol stability (ES), rennet clotting time, and casein micelle size were analyzed, together with some compositional factors such as fat, total protein, lactose, total and ionic calcium, magnesium, citrate, phosphorus, sodium, and potassium. Total Ca (36.2 mM) and free ionic Ca (2.58 mM), Mg (5.9 mM), P (32.2 mM), and Na (24.1 mM) appeared to be high on d 5 postpartum, having decreased substantially over the first 5 d; they gradually decreased thereafter. The average pH on d 5 was only 6.49, compared with 6.64 at 1 mo postpartum. Stability measurements showed that the average ES on d 5 was 70% and the rennet clotting time was 12.2 min, which were significantly lower than values at later stages. A number of milk properties including ES, pH, protein content, and Ca2+ concentration could be useful for identifying the point of transition from colostrum to the early lactation period. Knowing the composition and physical properties of colostrum and postcolostrum secretions will help establish when such milk is suitable for processing and determine the best use for that milk

Effect of minerals on casein micelle stability of cows' milk

The effects of minerals on casein micelle stability of individual cows' milk, throughout a complete lactation, were investigated. Calcium and calcium ions, magnesium, phosphorus, sodium, potassium and citrate contents were analysed, together with the following physical properties of milk; pH, ethanol stability, rennet clotting time and coagulum firmness. There was an inverse non-linear relationship between free calcium ion concentration and ethanol stability (ES; r=0.84). Rennet coagulation time showed a weaker relationship with free calcium ion concentration (r=0.44) but a stronger relationship with pH (r=0.66). In addition, samples containing higher amounts of free calcium ions produced a firmer gel. Citrate in natural samples acts as a stabilizing factor, as it slightly improves milk stability. Potassium, on the other hand, exhibited a negative correlation, but only with rennet clotting time (r=-0.52). Throughout lactation the average values were; free Ca 21 concentration 1.88 mm,, pH 6.63, ES 83.2% and clotting time 13.6 min. The equilibrium relationship between pH and free Ca2+ concentration was investigated by adjusting milk pH from 5.9 to 7.1, using acid and alkali. There was a good inverse linear relationship between pH and log (free Ca 21) for individual milk samples, with a gradient of -0.62 and a standard deviation of 0.042