ACVIM consensus statement guidelines for the diagnosis, classification, treatment, and monitoring of pulmonary hypertension in dogs.

Pulmonary hypertension (PH), defined by increased pressure within the pulmonary vasculature, is a hemodynamic and pathophysiologic state present in a wide variety of cardiovascular, respiratory, and systemic diseases. The purpose of this consensus statement is to provide a multidisciplinary approach to guidelines for the diagnosis, classification, treatment, and monitoring of PH in dogs. Comprehensive evaluation including consideration of signalment, clinical signs, echocardiographic parameters, and results of other diagnostic tests supports the diagnosis of PH and allows identification of associated underlying conditions. Dogs with PH can be classified into the following 6 groups: group 1, pulmonary arterial hypertension; group 2, left heart disease; group 3, respiratory disease/hypoxia; group 4, pulmonary emboli/pulmonary thrombi/pulmonary thromboemboli; group 5, parasitic disease (Dirofilaria and Angiostrongylus); and group 6, disorders that are multifactorial or with unclear mechanisms. The approach to treatment of PH focuses on strategies to decrease the risk of progression, complications, or both, recommendations to target underlying diseases or factors contributing to PH, and PH-specific treatments. Dogs with PH should be monitored for improvement, static condition, or progression, and any identified underlying disorder should be addressed and monitored simultaneously

Effect of type of diet on blood and plasma taurine concentrations, cardiac biomarkers, and echocardiograms in 4 dog breeds

BACKGROUND: Associations of diet with dilated cardiomyopathy are under investigation. OBJECTIVES: That cardiac assessment would show abnormalities in healthy dogs eating grain-free (GF) diets or diets with Food and Drug Administration (FDA)-listed ingredients of concern (peas, lentils, or potatoes) as top 10 ingredients (FDA-PLP), but not in dogs eating grain-inclusive (GI) diets or diets without FDA-listed ingredients of concern (PLP) in the top 10 ingredients (NoFDA-PLP). ANIMALS: One hundred eighty-eight healthy Doberman Pinschers, Golden Retrievers, Miniature Schnauzers, and Whippets. METHODS: This study was an observational cross-sectional study. Echocardiograms, cardiac biomarkers, and blood and plasma taurine concentrations were compared between dogs eating GF (n = 26) and GI (n = 162) diets, and between FDA-PLP (n = 39) and NoFDA-PLP (n = 149) diets, controlling for age and breed. Demographic characteristics, murmurs, genetic status, and ventricular premature complexes (VPCs) during examination were compared between dogs eating different diet types. RESULTS: No differences in echocardiographic variables, N-terminal pro-B-type natriuretic peptide or whole blood taurine were noted between dogs eating different diet types. Dogs eating GF diets had higher median high-sensitivity cardiac troponin I (hs-cTnI) (GF 0.076 ng/mL [Interquartile range (IQR), 0.028-0.156] vs. GI 0.048 [IQR, 0.0026-0.080]; P \u3c .001) and higher median plasma taurine (GF 125 nmol/mL [IQR, 101-148] vs GI 104 [IQR, 86-123]; P = .02) than dogs eating GI diets. Dogs eating FDA-PLP diets had higher median hs-cTnI (0.059 ng/mL [IQR, 0.028-0.122]) than dogs eating NoFDA-PLP diets (0.048 [IQR, 0.025-0.085]; P = .006). A greater proportion of dogs eating FDA-PLP diets (10%) had VPCs than dogs eating NoFDA-PLP diets (2%; P = .04). CONCLUSIONS AND CLINICAL IMPORTANCE: Higher hs-cTnI in healthy dogs eating GF and FDA-PLP diets might indicate low-level cardiomyocyte injury

Breed differences in natriuretic peptides in healthy dogs

Background: Measurement of plasma concentration of natriuretic peptides (NPs) is suggested to be of value in diagnosis of cardiac disease in dogs, but many factors other than cardiac status may influence their concentrations. Dog breed potentially is 1 such factor. Objective: To investigate breed variation in plasma concentrations of pro-atrial natriuretic peptide 31-67 (proANP 31-67) and N-terminal B-type natriuretic peptide (NT-proBNP) in healthy dogs. Animals: 535 healthy, privately owned dogs of 9 breeds were examined at 5 centers as part of the European Union (EU) LUPA project. Methods: Absence of cardiovascular disease or other clinically relevant organ-related or systemic disease was ensured by thorough clinical investigation. Plasma concentrations of proANP 31-67 and NT-proBNP were measured by commercially available ELISA assays. Results: Overall significant breed differences were found in proANP 31-67 (P?<?0001) and NT-proBNP (P?<?0001) concentrations. Pair-wise comparisons between breeds differed in approximately 50% of comparisons for proANP 31-67 as well as NT-proBNP concentrations, both when including all centers and within each center. Interquartile range was large for many breeds, especially for NT-proBNP. Among included breeds, Labrador Retrievers and Newfoundlands had highest median NT-proBNP concentrations with concentrations 3 times as high as those of Dachshunds. German Shepherds and Cavalier King Charles Spaniels had the highest median proANP 31-67 concentrations, twice the median concentration in Doberman Pinschers. Conclusions and Clinical Importance: Considerable interbreed variation in plasma NP concentrations was found in healthy dogs. Intrabreed variation was large in several breeds, especially for NT-proBNP. Additional studies are needed to establish breed-specific reference ranges. 2014 by the American College of Veterinary Internal Medicine.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

A Large Animal Model of Right Ventricular Failure due to Chronic Thromboembolic Pulmonary Hypertension: A Focus on Function

Chronic thromboembolic pulmonary hypertension (CTEPH) is a debilitating disease that progresses to right ventricular (RV) failure and death if left untreated. Little is known regarding the progression of RV failure in this disease, greatly limiting effective prognoses, and therapeutic interventions. Large animal models enable the use of clinical techniques and technologies to assess progression and diagnose failure, but the existing large animal models of CTEPH have not been shown to replicate the functional consequences of the RV, i.e., RV failure. Here, we created a canine embolization model of CTEPH utilizing only microsphere injections, and we used a combination of right heart catheterization (RHC), echocardiography (echo), and magnetic resonance imaging (MRI) to quantify RV function. Over the course of several months, CTEPH led to a 6-fold increase in pulmonary vascular resistance (PVR) in four adult, male beagles. As evidenced by decreased cardiac index (0.12 ± 0.01 v. 0.07 ± 0.01 [L/(min*kg)]; p &lt; 0.05), ejection fraction (0.48 ± 0.02 v. 0.31 ± 0.02; p &lt; 0.05), and ventricular-vascular coupling ratio (0.95 ± 0.09 v. 0.45 ± 0.05; p &lt; 0.05), as well as decreased tricuspid annular plane systolic excursion (TAPSE) (1.37 ± 0.06 v. 0.86 ± 0.05 [cm]; p &lt; 0.05) and increased end-diastolic volume index (2.73 ± 0.06 v. 2.98 ± 0.02 [mL/kg]; p &lt; 0.05), the model caused RV failure. The ability of this large animal CTEPH model to replicate the hemodynamic consequences of the human disease suggests that it could be utilized for future studies to gain insight into the pathophysiology of CTEPH development, following further optimization

A Novel In Vivo Approach to Assess Radial and Axial Distensibility of Large and Intermediate Pulmonary Artery Branches

Pulmonary arteries (PAs) distend to accommodate increases in cardiac output. PA distensibility protects the right ventricle (RV) from excessive increases in pressure. Loss of PA distensibility plays a critical role in the fatal progression of pulmonary arterial hypertension (PAH) toward RV failure. However, it is unclear how PA distensibility is distributed across the generations of PA branches, mainly because of the lack of appropriate in vivo methods to measure distensibility of vessels other than the large, conduit PAs. In this study, we propose a novel approach to assess the distensibility of individual PA branches. The metric of PA distensibility we used is the slope of the stretch ratio-pressure relationship. To measure distensibility, we combined invasive measurements of mean PA pressure with angiographic imaging of the PA network of six healthy female dogs. Stacks of 2D images of the PAs, obtained from either contrast enhanced magnetic resonance angiography (CE-MRA) or computed tomography digital subtraction angiography (CT-DSA), were used to reconstruct 3D surface models of the PA network, from the first bifurcation down to the sixth generation of branches. For each branch of the PA, we calculated radial and longitudinal stretch between baseline and a pressurized state obtained via acute embolization of the pulmonary vasculature. Our results indicated that large and intermediate PA branches have a radial distensibility consistently close to 2%/mmHg. Our axial distensibility data, albeit affected by larger variability, suggested that the PAs distal to the first generation may not significantly elongate in vivo, presumably due to spatial constraints. Results from both angiographic techniques were comparable to data from established phase-contrast (PC) magnetic resonance imaging (MRI) and ex vivo mechanical tests, which can only be used in the first branch generation. Our novel method can be used to characterize PA distensibility in PAH patients undergoing clinical right heart catheterization (RHC) in combination with MRI

Use of immunotherapy to enhance the efficacy of ceftazidime for the treatment of acute pulmonary Burholderia pseudomallei infection

2010 Spring.Includes bibliographic references (pages 88-94).Covers not scanned.Print version deaccessioned 2022.B. pseudomallei is a soil bacterium endemic to Southeast Asia and northern Australia and is the causative agent of melioidosis. This organism is capable of causing acutely lethal pneumonia in humans when inhaled and is inherently resistant to many commonly used antimicrobials, thus making pulmonary B. pseudomallei infection difficult to treat. Effective treatment requires prolonged antibiotic therapy and, even with appropriate treatment, relapse is common. With increasing incidence of this disease in endemic regions and renewed interest in this bacterium as a potential biowarfare agent, more effective treatment approaches are needed. We investigated the ability of immunotherapy to enhance the effectiveness of antimicrobial therapy for the treatment of pulmonary B. pseudomallei infection. Immunotherapy with cationic liposome-DNA complexes (CLDC), potent stimulators of innate immunity and pro-inflammatory cytokine production, combined with ceftazidime antimicrobial therapy elicited synergistic inhibition of intracellular B. pseudomallei replication in infected alveolar macrophages and protected mice from acutely lethal i.n. challenge with B. pseudomallei. Mice treated with CLDC and ceftazidime also had significantly reduced organ bacterial burdens. We determined in vitro that IFN-y elicited by CLDC administration was the predominant cytokine responsible for the synergistic interaction with ceftazidime. Treatment of alveolar macrophages and mice with recombinant IFN-y as a substitute for CLDC also significantly increased the efficacy of ceftazidime in the treatment of B. pseudomallei infection. As a result, we concluded that immuno-antimicrobial therapy consisting of an IFN-y-inducing immunotherapeutic and a conventional antimicrobial may improve the treatment of B. pseudomallei infection via augmentation of antimicrobial efficacy