Radiographic Measurements of the Cardiac Silhouette and Comparison with Other Radiographic Landmarks in Wild Galahs (Eolophus roseicapilla).

BACKGROUND: Part of the diagnostic workup for cardiac diseases is radiographic imaging. To determine an enlarged heart, species-specific reference values are necessary. Wild birds are rarely diagnosed with cardiac disease, and only a few studies have been done to investigate the cardiac silhouette in wild birds. METHODS: In this retrospective study, the cardiac silhouette of 36 wild galahs, presented at the hospital, was investigated in relation to other anatomic landmarks like the thoracic width, clavicula width, synsacrum width, distance between the third and fourth rib, distance of the clavicula, and length and height of the sternum using a digital DICOM viewer. RESULTS: The cardiac width was significant compared to the thoracic width with a minimum to maximum of 50 to 65%. The cardiac width compared with the coracoid width also showed significant results with a minimum to maximum range of 570 to 743%. A significant correlation was found between the weight and the cardiac width and length. CONCLUSION: The cardiac silhouette in wild galahs is easily measured in both radiographic views, and the heart size can be compared to other anatomical landmarks.

Evaluation of radiographic predictors of left heart enlargement in dogs with known or suspected cardiovascular disease.

Radiographic assessment of heart size is important for clinical management of dogs with cardiovascular disease (CVDz). We sought to compare the ability of vertebral heart size (VHS), vertebral left atrial size (VLAS), and radiologists' assessment of left atrial size (RadLAE) to predict echocardiographic left atrial size (EchoLAE), an important marker of left heart disease severity. We also compared the ability of VHS and VLAS to predict echocardiographic criteria for ACVIM stage B2 (EchoB2) in dogs with myxomatous mitral valve disease (MMVD). This prospective observational study enrolled 183 dogs with known or suspected CVDz that had an echocardiographic examination and thoracic radiographs obtained within 24 h. Compared to increased VHS, VLAS >2.3 was a more accurate predictor of EchoLAE (P = .002). VLAS >2.3 and RadLAE (both P <.0001) were independently associated with EchoLAE but VHS was not (P = .45). Optimal cutoffs for VLAS and VHS to predict EchoLAE were >2.3 vertebrae (sensitivity [Sn] = 90.3%, specificity [Sp] = 73.6%) and >11.1 vertebrae (Sn = 75.8%, Sp = 76.0%), respectively. Diagnostic accuracy of VLAS (AUC 0.84, 95% CI 0.73-0.92) and VHS (AUC 0.78, 95% CI 0.66-0.88) to predict EchoB2 in dogs with subclinical MMVD (n = 64) were not significantly different (P = .17). Results demonstrate that VLAS and RadLAE were superior indicators of EchoLAE compared to VHS in dogs with known or suspected CVDz. Both VLAS and VHS are useful predictors of EchoB2 in dogs with subclinical MMVD. When echocardiography is unavailable, VLAS represents a useful radiographic measurement to aid clinical management of dogs with known or suspected CVDz.

Radiographic Reference Intervals of the Cardiac Silhouette Width in the Bald Eagle (Haliaeetus leucocephalus).

Radiograph imaging is an important diagnostic tool for assessing cardiac size in avian patients. The bald eagle (Haliaeetus leucocephalis), once on the United States Federal List of Endangered and Threatened Wildlife and Plants, is now a thriving species in the United States. However, there is surprisingly little information regarding bald eagle cardiac reference values obtained through radiographic imaging for use in assessment of cardiac disease in this species. This study was performed to establish reference values of cardiac size in the bald eagle. Ventrodorsal radiographic images were taken from 9 healthy birds obtained from a raptor rehabilitation facility. Cardiac silhouette width to thorax width, cardiac silhouette width to sternum width, cardiac silhouette width to hepatic silhouette width, and cardiac silhouette width to coracoid width were obtained. Ratios were calculated between the respective areas measured. The results showed that the cardiac silhouette averages 44%-52% of the thoracic width, 71%-86% of the sternal width, 94%-117% of the width of the hepatic silhouette, and 500%-920% of the coracoid width. In the individuals studied there was a strong correlation between cardiac silhouette width to thoracic and sternal width whereas cardiac width with hepatic and coracoid widths had a moderate to weak correlation respectively. The values obtained in this study can be used to radiographically assess the cardiac size of bald eagles, thus aiding in the diagnosis of cardiomegaly in this species.

Radiographic Reference Values for the Cardiac Silhouette in Bonelli's Eagle (Aquila fasciata).

Radiographs are an important diagnostic tool available in wildlife hospitals to evaluate the size of the avian heart. Despite the large variety wild birds in the Iberian peninsula, clinical studies addressing these species are lacking. To establish reference values for cardiac size in the Bonelli's eagle (Aquila fasciata), ventrodorsal radiographs of 20 healthy birds were obtained, and the width of the cardiac silhouette, sternum, thorax, coracoid, and hepatic silhouette were measured. The ratios between cardiac width and other mentioned indices were calculated. Results showed that cardiac silhouette width should occupy 81%-93% of sternal width, 48%-57% of thoracic width, and 506%-673% of coracoid width. The cardiac silhouette width was strongly correlated with sternal and thoracic widths. A moderate correlation was found between the width of the heart and the width of the coracoid. No significant correlation was found between width of the cardiac silhouette and the hepatic silhouette. These results support that sternal and thoracic widths should be used preferentially when evaluating the width of the cardiac silhouette in this species. The values obtained in this study can be used as a reference for normal cardiac size when evaluating radiographs of Bonelli's eagles.

RADIOGRAPHIC EVALUATION OF CARDIAC SILHOUETTE IN CLINICALLY HEALTHY HUMBOLDT PENGUINS ( SPHENISCUS HUMBOLDTI).

Wild populations of Humboldt penguins ( Spheniscus humboldti) on the coasts of Chile and Peru have been declining because of food scarcity caused by the El Niño Southern Oscillation and human interference. Part of conserving this vulnerable and threatened species is maintaining the health of penguins within zoo collections. A variety of cardiovascular diseases has been reported in individuals from the Spheniscidae family including ventricular septal defects, Dirofilaria immitis infection, pulmonary hypertension, and valvular dysplasia, ultimately resulting in congestive heart failure. An accurate clinical picture of cardiovascular disease in Humboldt penguins requires diagnostics tailored to this specific species. The aim of this study was to establish a routine methodology for evaluating the cardiac silhouette of clinically healthy Humboldt penguins using vertebral heart scale (VHS), cardiocoelomic width ratio (CCWR), and a novel cardiac silhouette-to-keel ratio (CKR). Ventrodorsal and right lateral radiographs were taken of 10 mature Humboldt penguins during routine health evaluations. An echocardiographic exam of each penguin was performed to confirm that there was no evidence of cardiac structural remodeling from disease. Two penguins were excluded on the basis of echocardiographic findings; therefore, data from eight penguins were used to calculate objective cardiac measurements for the clinically healthy population. Right lateral radiographs were used to determine VHS (7.4-10.4) and CKR (3.4-4.4). Ventrodorsal radiographs were used for calculating CCWR (0.45-0.59). The excluded penguins had CCWRs that were outside the 95% confidence interval for the range generated by this study. This initial work supports that standardizing radiographic views provides objective measures for cardiac silhouette evaluation in this species. Further research in larger populations and comparison with birds having confirmed cardiac disease is needed to determine the value of these three measurement techniques in Humboldt penguins.

Echocardiographic parameters and vertebral heart size (VHS) in lambs during the neonatal period / Parâmetros ecocardiográficos e tamanho cardíaco vertebral (VHS) em cordeiros durante o período neonatal

Due to cardiac immaturity, newborns have a different morphology and cardiac output when compared with adults. The purpose of this study was to describe the cardiac changes in echocardiographic characteristics and vertebral heart size (VHS) in newborn lambs during the neonatal period. Twenty-eight healthy Ile de France lambs were evaluated from birth to 35 days old. With the assistance of echocardiography, this study evaluated, both in systole and diastole, indexes related to the right and left ventricles, the aorta (Ao), the left atrium (LA), the E point to septal separation (EPSS) and the thickness of the interventricular septum (VSd, VSs). The left atrium-to-aorta ratio (LA:Ao) was analyzed and both the shortening (SF%) and ejection fractions were calculated (EF%). The VHS was obtained by measuring the heart's long and short axes and comparing it to the thoracic vertebrae. Throughout the first 35 days, the results obtained demonstrated an increased LV:RV ratio when compared to adult lambs. The calculated indexes and the LA:Ao ratio did not present statistically significant differences. The VHS values were normally distributed, presenting a mean of 9.67 vertebrae (v) during the entire period. Both radiographic and echocardiographic parameters showed significant differences between the analyzed moments. The VHS values ranged from 8.4v at the minimum end to 11.2v at the maximum. In order to prevent these changes from being misdiagnosed as heart diseases, this study contributed to take note of neonatal physiological anatomy peculiarities and in addition, it describes the parameters for this age in Ilê de France lambs.(AU)

Devido à imaturidade cardíaca, os recém-nascidos apresentam uma morfologia e débito cardíacos diferenciados quando comparado aos adultos. O objetivo deste estudo foi descrever as alterações cardíacas ecocardiográficas e silhueta cardíaca ao exame radiográfico a partir do método VHS (vertebral heart size) em cordeiros recém-nascidos durante o período neonatal. Vinte e oito cordeiros saudáveis da raça Ile de France foram avaliados desde o nascimento até os 35 dias de idade. Ao exame ecocardiográfico avaliou-se em sístole e diástole, os índices relacionados aos ventrículos direito (VD) e esquerdo (VE), a parede livre do ventrículo esquerdo, aorta (Ao), átrio esquerdo (Ae), septo e ponto E, e diâmetros finais. Foi feita a relação entre o átrio esquerdo e aorta, além da fração de ejeção e de encurtamento. O VHS foi mensurado a partir do tamanho dos eixos longo e curto do coração em relação às vértebras torácicas. Os resultados obtidos demonstraram aumento do VE em relação ao VD no decorrer dos 35 dias (p<0,05). Os índices calculados e a relação AE:Ao não tiveram diferença. Os valores de VHS tiveram distribuição normal com média de 9,67 vértebras em todo o período. Os parâmetros radiográficos e ecocardiográficos mostraram diferenças significativas entre os momentos analisados. Os valores VHS variaram de 8.4 a 11.2 vertebras. Para evitar que essas alterações sejam erroneamente interpretadas como cardiopatias na espécie, este estudo demonstra às peculiaridades do desenvolvimento cardíaco neonatal em cordeiros, além de descrever parâmetros para esta faixa etária em cordeiros da raça Ilê de France.(AU)

Assessment of the vertebral heart scale and cardiothoracic ratio to standardize the heart size of collared peccaries (Tayassu tajacu Linnaeus, 1758) restrained with ketamine and midazolam / Avaliação do vertebral heart scale e índice cardiotorácico na padronização do tamanho cardíaco de cateto (Tayassu tajacu Linnaeus, 1758) contidos com cetamina e midazolam

Wild species, especially those threatened with extinction, are increasingly being investigated to obtain information that can be useful for their preservation. The objective of the present study was to standardize the vertebral heart scale (VHS) and cardiothoracic ratio (CTR) of the collared peccary (Tayassu tajacu Linnaeus, 1758) sedated with ketamine and midazolam. Fourteen clinically healthy collared peccaries were examined in the two-year age group weighing 15-22kg. The animals were submitted to digital radiography of the thorax in lateral and dorsal ventral projections to calculate the VHS and CTR. The VHS mean values for males and females was 8.88±0.51v for right recumbency and 8.84±0.39v for left decubitus, and there were no significant between-gender differences regarding recumbency (p>0.05). The CTR showed mean values of 0.50±0.05 (males) and 0.45±0.04 (females), but the gender-differences were not significant (p>0.05). A positive correlation was shown between VHS and CTR (r=0.98, right decubitus; r=0.96, left decubitus). Establishing reference values for heart measurements in collared peccaries using digital radiography of the thorax permitted standardization of the VHS and CTR values for this wild species. In the studied wild animal model, the VHS and CTR heart assessment indexes were shown to be essential diagnostic tools for investigations of alterations in the size of the cardiac silhouette.(AU)

Espécies silvestres têm sido cada vez mais exploradas como forma de obter informações que favoreçam sua conservação, especialmente aquelas ameaçadas de extinção. Este trabalho teve por objetivo a padronização dos valores de VHS (vertebral heart scale) e índice cardiotorácico (ICT) de catetos (Tayassu tajacu Linnaeus, 1758) contidos com Cetamina e Midazolam. Foram avaliados 14 catetos clinicamente saudáveis, com faixa etária de 2 anos e variação média de peso entre 15 a 22Kg. Os animais foram submetidos a radiografia digital de tórax em projeções laterolaterais e dorsoventrais para o cálculo do vertebral heart scale (VHS) e Índice Cardiotorácico (ICT). O VHS evidenciou valores médios entre machos e fêmeas de 8,88±0,51v para decúbito direito e 8,84±0,39v para decúbito esquerdo, não ocorrendo diferença estatística entre os decúbitos (p>0,05). O ICT revelou valores médios de 0,50±0,05 (machos) e de 0,45±0,04 (fêmeas), não sendo verificada diferença estatística significativa entre os sexos (p>0,05). Verificou-se correlação positiva entre VHS e o ICT (r=0,98, decúbito direito, r= 0,96, decúbito esquerdo). O estabelecimento dos valores de referência para mensurações cardíacas em catetos, a partir de radiografias digitais do tórax, permitiu a padronização do VHS e ICT para esta espécie silvestre. No modelo animal silvestre estudado, os índices de avaliação cardíaca VHS e ICT mostraram-se como uma ferramenta diagnóstica imprescindível para investigações sobre as alterações do tamanho da silhueta cardíaca.(AU)

CARDIOTHORACIC RATIO AND VERTEBRAL HEART SCALE IN CLINICALLY NORMAL BLACK-RUMPED AGOUTIS (DASYPROCTA PRYMNOLOPHA, WAGLER 1831).

Wild rodents, such as the lowland paca (Cuniculus paca), capybara (Hydrochoerus hydrochaeris), rock cavy (Kerodon rupestris), guinea pig (Cavia aperea), and black-rumped agouti (Dasyprocta prymnolopha) are intensely hunted throughout Amazonia and at the semiarid regions of northeastern Brazil. To contribute to the preservation of these species, more information about their anatomy, physiology and pathophysiology is needed. The aim of this study was to standardize the vertebral heart scale (VHS) and cardiothoracic ratio (CTR) in clinically normal black-rumped agouti, as well as to compare the results of these two methods, which are commonly used to evaluate the cardiac silhouette in domestic animals. Twelve healthy black-rumped agoutis, divided into two groups (six males and six females), obtained from the Nucleus for Wild Animal Studies and Conservation at the Federal University of Piauí, were radiographed in right and left lateral and dorsoventral projections. The values of the VHS were 8.00±0.31v (the number of thoracic vertebral length spanned by each dimension, starting at T4) for males and 8.11±0.41v for females, and there was no statistical difference between the decubitus (right and left) or between males and females (P>0.05). The CTR mean values obtained were 0.51±0.03 for males, and 0.52±0.02 for females, and there was no statistical difference between the genders (P>0.05). However, there was positive correlation between VHS and CTR (r=0.77 right decubitus and r=0.82 left decubitus). The thoracic and heart diameter had mean values of 6.72±0.61 and 3.48±0.30 cm (males), and for the females, it was 6.61±0.51 and 3.5±0.30 cm, respectively, and there was statistical difference between the genders. The results demonstrated high correlation between the VHS and CTR producing similar results, indicating similar clinical precision for assessing the size of the cardiac silhouette in the black-rumped agoutis.

Avaliação radiográfica da silhueta cardíaca pelo método vertebral heart size em cães da raça Yorkshire Terrier clinicamente normais / Radiographic evaluation of the cardiac silhouette in clinically normal Yorkshire Terrier dogs through the vertebral heart size method

Determinou-se valor médio do vertebral heart size (VHS) em cães da raça Yorkshire Terrier. Foram selecionados 30 cães clinicamente normais, com média de peso de 2,42±0,64kg e idades entre um e seis anos. Os animais foram submetidos ao exame radiográfico do tórax nas projeções lateral direita, ventrodorsal e dorsoventral. Foram feitas mensurações para avaliação cardíaca e da profundidade e largura torácicas. O valor médio de VHS foi de 9,9±0,6 vértebras na projeção lateral, 10,1±0,6 vértebras na projeção ventrodorsal e 10,0±0,6 vértebras na projeção dorsoventral. Não houve diferença entre esses valores. Cinco animais (16,7 por cento) apresentaram VHS acima de 10,5 vértebras, valor sugerido como limite superior para a maioria das raças, em projeção lateral. Os valores de VHS correlacionaram-se com peso corporal nas projeções lateral e ventrodorsal. A razão profundidade:largura torácica apresentou valor médio de 0,75±0,06. Não foi observada correlação entre a qualidade do tórax e o VHS.

The mean vertebral heart size (VHS) was established for Yorkshire Terrier dogs. Thirty clinically normal dogs with mean weight of 2.42±0.64kg and ages varying from one to six years of age, were studied. The animals were submitted to right lateral, ventrodorsal and dorsoventral thoracic radiographs. The Buchanan e Bücheler method was applied to the cardiac silhouette and thoracic depth and width. The VHS was 9.9±0.6 vertebrae on lateral, 10.1±0.6 on ventrodorsal and 10.0±0.6 on dorsoventral radiographs. There was no difference among these values. Five animals (16.7 percent) presented VHS values exceeding 10.5, the value suggested as upper limit for most breeds in lateral view. However, 95 percent of the animals in this study provide VHS values below the upper limit, and this should be equal to 11 vertebrae. The VHS values had significant correlation with body weight on lateral and VD radiographs. The mean depth:width ratio was 0.75±0.06. There was no correlation among VHS and depth:width ratios.