Radiographic evaluation of cardiac silhouette in healthy Maine Coon cats

Abstract

Determining the size of the heart is important for evaluating cardiac patients, because the increase of the cardiac silhouette in the chest radiography can be indicative of heart disease. The vertebral heart size (VHS) method is useful because it allows objective assessment of the limits of cardiac silhouette, and can help assess cardiomegaly and document changes in heart size in response to treatment or disease progression. The aim of this study was to compare VHS values of Maine Coon cats (MCC) with values cited in the literature (7.5 ± 0.3 vertebrae) obtained in non Maine Coon cats (NMCC). Sixty three MCC underwent the physical examination, electrocardiography, echocardiography, laboratory tests (blood count, biochemistry, including liver and kidney function, and total T 4 ), as well as measurement of blood pressure. Faced with normal results, the cats were positioned in right lateral decubitus (right laterallateral projection), to perform chest radiography. The radiographic examinations were performed using the Fuji computed radiography system. The values of VHS found in the animals of this study were 7.61 ± 0.34 vertebrae with a minimum of 6.9 and of maximum 8.5 vertebrae. Statistical analysis performed by Student's t test identified a significant difference between the values obtained in this study with those in the literature (p = 0.03) for non Maine Coon cats. The highest values of VHS obtained in MCC may be associated with the size of this giant breed. Key words: Feline, VHS, image, heart Resumo A determinação do tamanho do coração é importante na avaliação de pacientes cardiopatas, pois o aumento da silhueta cardíaca, na radiografia torácica, pode ser indicativa de enfermidade cardíaca. O sistema VHS (vertebral heart size) é util porque permite avaliar, objetivamente, os limites da silhueta cardíaca, auxiliando na avaliação de cardiomegalia e documentando alterações do tamanho cardíaco em resposta ao tratamento ou à progressão da doença. O objetivo deste trabalho foi comparar valores de VHS de gatos Maine Coon (GMC) sadios com aqueles citados na literatura (7,5±0,3 vértebras) obtidos de gatos não Maine Coon (GNMC). Sessenta e três GMC foram avaliados por meio de exames físico, eletrocardiográfico, ecocardiográfico, laboratoriais (hemograma, funções hepática e renal, T 4 total), bem como pela determinação da pressão arterial. Frente a resultados normais, os animais foram posicionados em decúbito lateral direito (projeção látero-lateral direita), para realização da radiografia torácica, realizada utilizando o sistema Fuji de radiografia computadorizada. Os valores de VHS obtidos neste trabalho foram 7,61±0,34 vértebras, com mínimo de 6,9 e máximo de 8,5 vértebras. A análise estatística realizada pelo teste t de Student mostrou diferença significativa entre os valores ora obtidos em relação àqueles citados na literatura (p=0.03) para gatos não Maine Coon. Os valores de VHS maiores observados em GMC podem estar associados com o porte gigante desta raça de gatos.

Estimation of vertebral heart size and cardiothoracic ratio in Persian cats

“…It was determined that the VHS values we obtained from the thorax radiograph in this study conducted with the Persian cats were at 8.18 and 8.15 (8.16 ± 0.44 on average for 30 cats) vertebral level, respectively, in lateral radiograph and they were 8.67 and 8.81 in DV and VD radiographs for the male and female cat (8.74 ± 0.58 on average for 28 cats) vertebral level, respectively, and it was observed that they were higher than the VHS values of the other cat breeds specified in the literature (Litster & Buchanan, 2000a, 2000b; Ghadiri et al., 2008; Guglielmini et al., 2014; Oliveira et al., 2014; Bîrsan et al., 2016). Similarly, it has been emphasized in the study conducted on the vertebral heart size of pug, Boston terrier and bulldog breed dogs (Jepsen‐Grant et al., 2013) that the reason behind why VHS values of these breeds were higher than the VHS values reported by Buchanan and Bücheler (1995) for dogs (9.7 ± 0.5) may be due to the fact that these breeds were brachycephalic breeds.…”