Systolic blood pressure in anesthetized bitches measured with photoplethysmography

Background: Photoplethysmography is widely used in human medicine, with few studies on its use in veterinary medicine. Its sensor detects fluctuations in blood volume at the site, providing direct readings of cardiac pulse and peripheral oxygen saturation, as well as estimating cardiac output, respiratory rate and blood pressure. This study aimed to evaluate the use of photoplethysmography and compare it to vascular Doppler ultrasound as an indirect method of measuring systolic blood pressure in bitches undergoing elective ovariohysterectomy, using the invasive assessment of systolic blood pressure as a reference. Materials, Methods and Results: After clinical and laboratory evaluation, 34 healthy bitches were selected to undergo elective ovariohysterectomy. After food and water fasting, patients received pethidine hydrochloride intramuscularly as pre-anesthetic medication, followed by anesthetic induction with fentanyl citrate and propofol intravenously. General anesthesia was maintained by inhalation with isoflurane diluted in 100% oxygen. Intraoperative analgesia consisted of continuous infusion of fentanyl citrate intravenously. The animals were randomly divided into 2 groups, the thoracic limb group (TLG) and the pelvic limb group (PLG). In each patient, non-invasive blood pressure measurement was obtained simultaneously with Doppler (DOP) and photoplethysmography (PPG). The sensors of both devices were placed on the end of the same limb. The PPG sensor was positioned in the interdigital region. In patients belonging to the TLG, the Doppler sensor was placed in the ventral region of the thoracic limb, under the ulnar artery. In PLG patients, the Doppler sensor was placed in the dorsal region of the pelvic limb, over the dorsal artery of the foot. The sphygmomanometer was positioned close to the sensors. For systolic blood pressure (SBP) measurement, the cuff was inflated until the Doppler sound signal and the plethysmographic wave were lost. The cuff was then deflated until the Doppler pulse sound resumed and the photoplethysmography showed at least 2 continuous waves on a regular basis. The corresponding pressure value observed on the manometer consisted of the SBP. The same 2 evaluators performed all SBP measurements: 1 responsible for the DOP method and the other for the PPG method; both were blind to the other's findings, thus minimizing potential bias in the results. All animals underwent cannulation of the auricular artery for invasive measurement of systolic blood pressure, using a multiparameter monitor. All blood pressure measurements were performed at 5-min intervals, as well as obtaining additional parameters (heart and respiratory rate, esophageal temperature, partial tissue oxygen saturation, carbon dioxide concentration) and electrocardiographic monitoring. All parameters were documented for further statistical analysis. A strong correlation (r² = 0.95) was obtained between the DOP and PPG methods regardless of the limb on which the sensors were placed. There was a low correlation between the invasive method of measuring systolic blood pressure and the other methods. There was better agreement between the DOP and PPG methods (r2 = -0.0061; P = 0.85) when systolic blood pressure was measured in the TLG. Discussion: In the PLG, the values obtained with the DOP and PPG methods were significantly higher than those obtained with the invasive method, while the values obtained in the TLG differed slightly. It was found that the best measurement site by non-invasive methods was the thoracic limb. It was concluded that the non-invasive methods showed a low correlation with the invasive method; however, both methods had similar characteristics and photoplethysmography can be used to replace the vascular Doppler method.

B-mode and Doppler ultrasonography of abdominal structures of the peccary (Tayassu tajacu, Linnaeus 1758) / [Ultrassonografias Doppler e modo-B das estruturas abdominais de catetos (Tayassu tajacu Linnaeus, 1758)]

This study used B-mode and Doppler ultrasonography to characterize the abdominal structures of healthy peccaries raised in captivity. Fifteen peccaries were used for this study. The urinary vesicle appeared as an ovoid structure, located in the abdominal and pelvic transition, with a hyperechogenic, thin, smooth, and regular wall. The kidneys presented retroperitoneal topography and had similar sizes. The kidney/aorta ratio had an average value of 10.53±15cm (right) and 10.23±0.12 (left). The right adrenal gland had a length of 1.93±0.34cm and diameter of 0.56±0.16cm. The left adrenal gland had a length of 1.85±0.42cm and diameter of 0.52±0.11cm. The spleen had a diameter of 1.13±0.18cm. The hepatic vein demonstrated polyphasic flow in pulsed Doppler, with two retrograde peaks and an anterograde peak with a flow velocity of 25.7±0.83cm/s. The abdominal aorta had a diameter of 0.58±0.05cm and a flow velocity of 115.17±5.32cm/s. The morphological and hemodynamic study of the abdominal structures of the peccary, observed through B-mode and Doppler ultrasonography, aided in identifying the size, shape, position, echogenicity, and echotexture of the abdominal organs and in making inferences about the normal parameters for these structures in this species.(AU)

Este estudo teve como objetivo utilizar as ultrassonografias de modo-B e Doppler para caracterizar as estruturas abdominais de um cateto sadio criado em cativeiro. Quinze catetos foram utilizados para este estudo. A vesícula urinária apareceu como uma estrutura ovoide, localizada na transição entre as partes abdominal e pélvica, com uma parede hiperecogênica, fina, lisa e regular. Os rins apresentaram topografia retroperitoneal e tamanhos semelhantes. A relação rim/aorta teve um valor médio de 10,53 ± 15cm (direita) e 10,23 ± 0,12cm (esquerda). A glândula adrenal direita tinha um comprimento de 1,93 ± 0,34cm e um diâmetro de 0,56 ± 0,16cm. A glândula suprarrenal esquerda tinha um comprimento de 1,85 ± 0,42cm e um diâmetro de 0,52 ± 0,11cm. O baço tinha um diâmetro de 1,13 ± 0,18cm. A veia hepática demonstrou fluxo polifásico no Doppler pulsátil, com dois picos retrógrados e um pico anterógrado com velocidade de fluxo de 25,7±0,83cm/s. A aorta abdominal tinha um diâmetro de 0,58 ± 0,05cm e uma velocidade de fluxo de 115,17±5,32cm/s. Os estudos morfológico e hemodinâmico das estruturas abdominais do queixada, observadas por meio das ultrassonografias modo-B e Doppler, auxiliaram na identificação do tamanho, da forma, da posição, da ecogenicidade e da ecotextura dos órgãos abdominais e na realização de inferências sobre os parâmetros de normalidade para as estruturas nas espécies.(AU)

Impact of hypotensive action of angiotensin converting enzyme inhibitor on ovarian-intraovarian blood flow and follicles development in goats hormonally stimulated with repeated FSH-ECG treatment

Background: Recent evidence shows that the renin-angiotensin system (RAS) participates in important reproductiveprocesses, such as steroidogenesis, folliculogenesis, oocyte maturation and ovulation. Several studies have proposed touse an angiotensin-converting enzyme (ACE) as a RAS modulator, aiming to improve reproductive efficiency, however,the presence of the main components of this system in reproductive tissues still need to be further investigated, since thephysiological functions seem to be species-specific. The aim of this study was to assess the impact of enalapril-maleate,an ACE inhibitor, during repeated gonadotropins treatment on ovarian blood flow and follicular development in goats.Materials, Methods & Results: Twenty Anglo-Nubian cross-bred goats were equally grouped according to parity (n= 10/group): nulliparous and multiparous parity. In each group, five animals were randomly selected to receive 0.4 mg.kg-1 ofenalapril-maleate during 11 days of estrus synchronization and gonadotropins treatments. The other animals received thesame volume of saline solution. Estrus synchronization of all goats was made by intramuscular ad-ministration of PGF2αanalog, followed 48 h later by intravaginal insertion of a controlled internal drug release device. Forty-eight h after devicewithdrawal, a single dose of 60 mg of FSH plus 300 UI of eCG was administered and repeated every 4 days to complete 3treatments. Transrectal ultrasonography was performed using pulsed and color Doppler to evaluate Doppler velocimetricsparameters of the ovarian artery and intraovarian blood flow, respec-tively, and B-mode real-time ultrasound scanner toevaluate the follicular development. In the females treated with enalapril-maleate was observed a significant reduction ofsystolic and diastolic peak, without difference according to parity. In addition, in the third session of hor-monal stimulation,only the groups (nulliparous and multiparous) not treated with...(AU)

Impact of hypotensive action of angiotensin converting enzyme inhibitor on ovarian-intraovarian blood flow and follicles development in goats hormonally stimulated with repeated FSH-ECG treatment

Background: Recent evidence shows that the renin-angiotensin system (RAS) participates in important reproductiveprocesses, such as steroidogenesis, folliculogenesis, oocyte maturation and ovulation. Several studies have proposed touse an angiotensin-converting enzyme (ACE) as a RAS modulator, aiming to improve reproductive efficiency, however,the presence of the main components of this system in reproductive tissues still need to be further investigated, since thephysiological functions seem to be species-specific. The aim of this study was to assess the impact of enalapril-maleate,an ACE inhibitor, during repeated gonadotropins treatment on ovarian blood flow and follicular development in goats.Materials, Methods & Results: Twenty Anglo-Nubian cross-bred goats were equally grouped according to parity (n= 10/group): nulliparous and multiparous parity. In each group, five animals were randomly selected to receive 0.4 mg.kg-1 ofenalapril-maleate during 11 days of estrus synchronization and gonadotropins treatments. The other animals received thesame volume of saline solution. Estrus synchronization of all goats was made by intramuscular ad-ministration of PGF2αanalog, followed 48 h later by intravaginal insertion of a controlled internal drug release device. Forty-eight h after devicewithdrawal, a single dose of 60 mg of FSH plus 300 UI of eCG was administered and repeated every 4 days to complete 3treatments. Transrectal ultrasonography was performed using pulsed and color Doppler to evaluate Doppler velocimetricsparameters of the ovarian artery and intraovarian blood flow, respec-tively, and B-mode real-time ultrasound scanner toevaluate the follicular development. In the females treated with enalapril-maleate was observed a significant reduction ofsystolic and diastolic peak, without difference according to parity. In addition, in the third session of hor-monal stimulation,only the groups (nulliparous and multiparous) not treated with...

Estenose da artéria pulmonar em cães: revisão de literatura

A estenose da artéria pulmonar corresponde uma doença cardíaca congênita, de maior frequência na espécie canina. Caracteriza-se por estreitamento do lúmen arterial pulmonar. Nos cães, corresponde à terceira patologia cardíaca de maior frequência e acomete principalmente o Buldogue inglês. Os animais acometidos geralmente não apresentam sintomatologia, e em casos mais graves é possível observar sinais de insuficiência cardíaca congênita direita e ate mesmo sincope. O método de escolha para o correto diagnóstico da doença é o exame ecocardiográfico, o qual permite detectar a lesão, classifica-la e ainda determinar o se grau de gravidade e as alterações secundarias.(AU)

Pulmonary artery stenosis corresponds to a congenital heart disease, more frequent in the canine species. It is characterized by narrowing of the pulmonary arterial lumen. In dogs, it corresponds to the third most frequent cardiac pathology and affects mainly the English Bulldog. Affected animals generally do not show symptoms, and in more severe cases it is possible to observe signs of right congenital heart failure and even syncope. The method of choice for the correct diagnosis of the disease is the echocardiographic examination, which allows to detect the lesion, classify it and also determine its degree of severity and secondary changes.(AU)

Estenose da artéria pulmonar em cães: revisão de literatura

A estenose da artéria pulmonar corresponde uma doença cardíaca congênita, de maior frequência na espécie canina. Caracteriza-se por estreitamento do lúmen arterial pulmonar. Nos cães, corresponde à terceira patologia cardíaca de maior frequência e acomete principalmente o Buldogue inglês. Os animais acometidos geralmente não apresentam sintomatologia, e em casos mais graves é possível observar sinais de insuficiência cardíaca congênita direita e ate mesmo sincope. O método de escolha para o correto diagnóstico da doença é o exame ecocardiográfico, o qual permite detectar a lesão, classifica-la e ainda determinar o se grau de gravidade e as alterações secundarias.

Pulmonary artery stenosis corresponds to a congenital heart disease, more frequent in the canine species. It is characterized by narrowing of the pulmonary arterial lumen. In dogs, it corresponds to the third most frequent cardiac pathology and affects mainly the English Bulldog. Affected animals generally do not show symptoms, and in more severe cases it is possible to observe signs of right congenital heart failure and even syncope. The method of choice for the correct diagnosis of the disease is the echocardiographic examination, which allows to detect the lesion, classify it and also determine its degree of severity and secondary changes.

Left ventricular adaptations in herding dogs

Background: Athlete’s heart syndrome comprises a set of functional and anatomic cardiac changes secondary to intenseand prolonged physical exercise in humans and animals. The heart adapts to the type of activity performed, and Dopplerechocardiography is the best tool for identifying these changes. Speckle tracking echocardiography (STE) has providednew data on cardiovascular adaptations secondary to physical exercise in humans, information that conventional echocardiography cannot provide. Although physical activity and work in dogs are well documented, there are few studies oncardiovascular adaptations secondary to exercise in dogs, and no studies to date evaluated these adaptations using STE.Materials, Methods & Results: A total of 31 dogs of the Border Collie and Ovelheiro Gaúcho Brasileiro breeds weredivided into two groups: a herding group (HG, n = 15), which performed herding activity five to six times a week for atleast 4 months, and a sedentary group (SG, n = 16), with no history of physical activity in the past twelve months. Alldogs were previously subjected to electrocardiography and blood pressure measurement. After that, the animals underwentechocardiographic examination at rest at a single time point. The data were analyzed by two-way multivariate analysisof variance (ANOVA) at a level of significance of 5% (P < 0.05) and a trend at 90% (P < 0.1). The dogs of the HG hadhigher values for left-ventricular end-systolic diameter (LVESD) and systolic volume (SV), and lower values for leftventricular myocardial performance index (Tei index) and systolic septal movement. STE results indicated that the HGpresented lower values for strain and strain rate in some myocardial segments in the radial, circumferential, longitudinal,and transverse directions.Discussion: The increase in LVESD is justified by the increase in preload (volume) required to meet the increased oxygendemand...

Left ventricular adaptations in herding dogs

Background: Athletes heart syndrome comprises a set of functional and anatomic cardiac changes secondary to intenseand prolonged physical exercise in humans and animals. The heart adapts to the type of activity performed, and Dopplerechocardiography is the best tool for identifying these changes. Speckle tracking echocardiography (STE) has providednew data on cardiovascular adaptations secondary to physical exercise in humans, information that conventional echocardiography cannot provide. Although physical activity and work in dogs are well documented, there are few studies oncardiovascular adaptations secondary to exercise in dogs, and no studies to date evaluated these adaptations using STE.Materials, Methods & Results: A total of 31 dogs of the Border Collie and Ovelheiro Gaúcho Brasileiro breeds weredivided into two groups: a herding group (HG, n = 15), which performed herding activity five to six times a week for atleast 4 months, and a sedentary group (SG, n = 16), with no history of physical activity in the past twelve months. Alldogs were previously subjected to electrocardiography and blood pressure measurement. After that, the animals underwentechocardiographic examination at rest at a single time point. The data were analyzed by two-way multivariate analysisof variance (ANOVA) at a level of significance of 5% (P < 0.05) and a trend at 90% (P < 0.1). The dogs of the HG hadhigher values for left-ventricular end-systolic diameter (LVESD) and systolic volume (SV), and lower values for leftventricular myocardial performance index (Tei index) and systolic septal movement. STE results indicated that the HGpresented lower values for strain and strain rate in some myocardial segments in the radial, circumferential, longitudinal,and transverse directions.Discussion: The increase in LVESD is justified by the increase in preload (volume) required to meet the increased oxygendemand... (AU)

Estudo ecodopplercardiográfico em caprinos da raça Moxotó / Doppler echocardiography in goats Moxotó

Objetivou-se com este estudo reportar descrições acerca dos cortes ecocardiográficos no modo bidimensional, das dimensões cardíacas pelo modo unidimensional e dos índices de fluxo Doppler em caprinos da raça Moxotó. Foram utilizados 32 caprinos da raça Moxotó, distribuídos em quatro grupos por categoria de peso corporal, de igual número (n=8), em: G1 (5-10kg), G2 (10-15kg), G3 (15-20kg) e G4 (>20kg). Todos foram submetidos a um registro ecocardiográfico pelos modos bidimensional, modo-M, Doppler pulsado (PW), contínuo (CW) e de fluxo de cores (CF). A formação espectral das imagens ecocardiográficas foi satisfatória, contudo algumas adaptações foram necessárias para obtenção adequada dos cortes nos caprinos acima de 20 kg. Os parâmetros ecocardiográficos em modo unidimensional (IVSd, IVSs, LVIDd, LVIDs, VPWd, LVPWs) e índices de função cardíaco (EF e FS) apresentaram uma correlação descritiva positiva com peso corporal enquadradas nas categorias estudadas. A separação septal do ponto E, mostrou-se constante dentre as categorias de peso investigadas, variando entre 0,1 a 0,41cm em caprinos da raça Moxotó. A relação Em/Am foi predominantemente " >1" em todos os caprinos estudados, com Emax > Amax em todas as categorias, não sendo sujeito a influência da frequência cardíaca dentre as categorias de peso estudados. O mesmo pode ser aplicado ao TRIV, que se mostrou uniforme dentre os intervalos de peso estudados. As velocidades de fluxo da valva aórtica individuais foram superiores a velocidade máxima do fluxo da valva pulmonar. Os tempos de ejeção dos fluxos aórtico e pulmonar apresentaram correlação positiva descritiva com o aumento do peso corporal. Condição também observada sobre o VTI dos espectros de fluxo, dada a relação direta desta variável com o volume sistólico inversamente à FC. O tempo de aceleração (TA) do fluxo pulmonar foi superior ao fluxo aórtico, sendo este relação direta com aumento do peso corporal por categoria estudada e inversamente à frequência cardíaca. Desta forma, a padronização das variáveis ecodopplercardiográficas na espécie caprina, deve sempre considerar particularidades relacionadas ao padrão racial, faixa etária e peso corporal, bem como estudos de repetibilidade e reprodutibilidade e adoção de elementos individuais referenciais para elaboração confiável de valores de normalidade.(AU)

This study describes the two-dimensional echocardiographic sections, M-mode cardiac dimensions, and Doppler flow indices in Moxotó goats. A total of 32 Moxotó goats were divided into four equal groups (n = 8) according to body weight class: G1 (5-10 kg), G2 (10-15kg), G3 (15-20kg) and G4 (>20kg). All animals underwent echocardiographic tests, two-dimensional and M-mode, and pulsed (PW), continuous (CW) and color flow (CF) Doppler. The spectral formation of echocardiographic images was satisfactory, although some adjustments were necessary to obtain adequate cuts/sections for goats above 20 kg. One-dimensional echocardiographic parameters (IVSD, IVSS, LVIDd, LVIDs, VPWd, LVPWs) and cardiac function index (EF and FS) showed a positive descriptive correlation with body weight in the categories studied. The septal separation of point E was constant among the weight categories investigated, ranging from 0.1 to 0.41cm. The Em/Am ratio was predominantly ">1", with Emax> Amax in all weight categories, and not affected by the heart rate among the studied weight classes. The IVRT was also uniform among the studied weight classes. The individual flow rates of the aortic valve were higher than the maximum flow rate of the pulmonary valve. The ejection times of the aortic and pulmonary flows were positively correlated with increasing body weight, something also observed on the VTI of flow spectra, given the direct relationship of this variable with the stroke volume inversely to FC. The acceleration time (AT) of pulmonary blood flow was greater than the aortic flow, and directly related to increasing body weight and inversely with heart rate. Thus, the standardization of Doppler echocardiographic variables in goats, should always consider breed, age and body weight as well as repeatability and reproducibility studies and adoption of individual reference elements for reliable development of normal values.(AU)

Estudo ecodopplercardiográfico em caprinos da raça Moxotó / Doppler echocardiography in goats Moxotó

Objetivou-se com este estudo reportar descrições acerca dos cortes ecocardiográficos no modo bidimensional, das dimensões cardíacas pelo modo unidimensional e dos índices de fluxo Doppler em caprinos da raça Moxotó. Foram utilizados 32 caprinos da raça Moxotó, distribuídos em quatro grupos por categoria de peso corporal, de igual número (n=8), em: G1 (5-10kg), G2 (10-15kg), G3 (15-20kg) e G4 (>20kg). Todos foram submetidos a um registro ecocardiográfico pelos modos bidimensional, modo-M, Doppler pulsado (PW), contínuo (CW) e de fluxo de cores (CF). A formação espectral das imagens ecocardiográficas foi satisfatória, contudo algumas adaptações foram necessárias para obtenção adequada dos cortes nos caprinos acima de 20 kg. Os parâmetros ecocardiográficos em modo unidimensional (IVSd, IVSs, LVIDd, LVIDs, VPWd, LVPWs) e índices de função cardíaco (EF e FS) apresentaram uma correlação descritiva positiva com peso corporal enquadradas nas categorias estudadas. A separação septal do ponto E, mostrou-se constante dentre as categorias de peso investigadas, variando entre 0,1 a 0,41cm em caprinos da raça Moxotó. A relação Em/Am foi predominantemente " >1" em todos os caprinos estudados, com Emax > Amax em todas as categorias, não sendo sujeito a influência da frequência cardíaca dentre as categorias de peso estudados. O mesmo pode ser aplicado ao TRIV, que se mostrou uniforme dentre os intervalos de peso estudados. As velocidades de fluxo da valva aórtica individuais foram superiores a velocidade máxima do fluxo da valva pulmonar. Os tempos de ejeção dos fluxos aórtico e pulmonar apresentaram correlação positiva descritiva com o aumento do peso corporal. Condição também observada sobre o VTI dos espectros de fluxo, dada a relação direta desta variável com o volume sistólico inversamente à FC. O tempo de aceleração (TA) do fluxo pulmonar foi superior ao fluxo aórtico, sendo este relação direta...(AU)

This study describes the two-dimensional echocardiographic sections, M-mode cardiac dimensions, and Doppler flow indices in Moxotó goats. A total of 32 Moxotó goats were divided into four equal groups (n = 8) according to body weight class: G1 (5-10 kg), G2 (10-15kg), G3 (15-20kg) and G4 (>20kg). All animals underwent echocardiographic tests, two-dimensional and M-mode, and pulsed (PW), continuous (CW) and color flow (CF) Doppler. The spectral formation of echocardiographic images was satisfactory, although some adjustments were necessary to obtain adequate cuts/sections for goats above 20 kg. One-dimensional echocardiographic parameters (IVSD, IVSS, LVIDd, LVIDs, VPWd, LVPWs) and cardiac function index (EF and FS) showed a positive descriptive correlation with body weight in the categories studied. The septal separation of point E was constant among the weight categories investigated, ranging from 0.1 to 0.41cm. The Em/Am ratio was predominantly ">1", with Emax> Amax in all weight categories, and not affected by the heart rate among the studied weight classes. The IVRT was also uniform among the studied weight classes. The individual flow rates of the aortic valve were higher than the maximum flow rate of the pulmonary valve. The ejection times of the aortic and pulmonary flows were positively correlated with increasing body weight, something also observed on the VTI of flow spectra, given the direct relationship of this variable with the stroke volume inversely to FC. The acceleration time (AT) of pulmonary blood flow was greater than the aortic flow, and directly related to increasing body weight and inversely with heart rate. Thus, the standardization of Doppler echocardiographic variables in goats, should always consider breed, age and body weight as well as repeatability and reproducibility studies and adoption of individual reference elements for reliable development of normal values.(AU)

Cardiovascular evaluation in bitches in oestrus, pregnancy and puerperium

Background: Pregnancy may change maternal hemodynamic, which is considered a physiological mechanism for adaptation. Cardiac output tends to be influenced by reductions in vascular resistance and increases in uterine vasculature, as well as reduced autonomic tone combined with gestational physiological anaemia and increased blood volume due to increased plasma volume and hormonal mechanisms. In bitches, few studies have been conducted investigating the changes of the system and the clinical implications for the mother and foetuses due to poor cardiac adaptation during pregnancy.Materials, Methods & Results: Systolic blood pressure (SBP), electrocardiographic and Doppler echocardiographic measurements and serum sodium (Na), potassium (K), calcium (Ca) and phosphorus (P) levels were evaluated in six bitches of reproductive age. An evaluation was performed in oestrus (M0), followed by evaluations at 25 (M1), 45 (M2), and 60 days (M3) after the last natural or artificial insemination and 15 days after delivery (M4). For the statistical analysis, the means, medians and the standard deviation were calculated. The data were analysed using ANOVA and the Tukey test, with significance level of 5%. A descriptive analysis was performed for color Doppler in echocardiogram evaluation, cardiac axis and rhythm in electrocardiogram evaluation. In the electrolytic evaluation, significant differences were found only in the serum levels of Na, noticed as a reduction in M0-M1 and M3-M2 and an increase in M1-M2 and M3-M4. No significant differences were observed in the SBP, although there was a tendency to SBP reduction. ECG parameters were not significantly different, with no rhythm or conduction disturbances. There was not a significant difference in HR. Four animals (66.6%) had axis deviation to the right when comparing the oestrous phase with the final quarter of pregnancy. The echocardiographic parameters did not show significant changes.[...]

Cardiovascular evaluation in bitches in oestrus, pregnancy and puerperium

Background: Pregnancy may change maternal hemodynamic, which is considered a physiological mechanism for adaptation. Cardiac output tends to be influenced by reductions in vascular resistance and increases in uterine vasculature, as well as reduced autonomic tone combined with gestational physiological anaemia and increased blood volume due to increased plasma volume and hormonal mechanisms. In bitches, few studies have been conducted investigating the changes of the system and the clinical implications for the mother and foetuses due to poor cardiac adaptation during pregnancy.Materials, Methods & Results: Systolic blood pressure (SBP), electrocardiographic and Doppler echocardiographic measurements and serum sodium (Na), potassium (K), calcium (Ca) and phosphorus (P) levels were evaluated in six bitches of reproductive age. An evaluation was performed in oestrus (M0), followed by evaluations at 25 (M1), 45 (M2), and 60 days (M3) after the last natural or artificial insemination and 15 days after delivery (M4). For the statistical analysis, the means, medians and the standard deviation were calculated. The data were analysed using ANOVA and the Tukey test, with significance level of 5%. A descriptive analysis was performed for color Doppler in echocardiogram evaluation, cardiac axis and rhythm in electrocardiogram evaluation. In the electrolytic evaluation, significant differences were found only in the serum levels of Na, noticed as a reduction in M0-M1 and M3-M2 and an increase in M1-M2 and M3-M4. No significant differences were observed in the SBP, although there was a tendency to SBP reduction. ECG parameters were not significantly different, with no rhythm or conduction disturbances. There was not a significant difference in HR. Four animals (66.6%) had axis deviation to the right when comparing the oestrous phase with the final quarter of pregnancy. The echocardiographic parameters did not show significant changes.[...](AU)

Evaluación cardiovascular del recién nacido ovino: revisión de literatura / Evaluation of the cardiovascular system of ovine neonate: review of the literature / Avaliação cardiovascular do neonato ovino: revisão de literatura

Así que un problema se divulga como patología en un sistema orgánico es necesaria que sea revisado y Comparado con el normal. Pocos estudios han informado de este patrón en el sistema cardiovascular del recién nacidos ovejas dejando un espacio con respecto a las diferencias entre recién nacidos y adultos. Durante el primer mes de vida se producen las cardiocirculatórias principales adaptaciones que permiten a los individuos llegar a la edad adulta. De esta revisión de literatura pretende discutir algunos de los principales métodos de evaluación cardiovasculares de ovínos recién nacidos, teniendo en cuenta el electrocardiograma, ecodopplercardiogram, examen radiográfico de tórax y la presión arterial sistémica, como los principales procedimientos, porque son métodos de diagnóstico importantes, utilizados principalmente para detectar no sólo los cambios del corazón como también para el análisis de la función normal del corazón.(AU)

To report a problem like as pathologic in an organic system is necessary for it to be reviewed and compared to standard. Few studies have reported this pattern in the cardiac system of newborn sheep leaving a gap with regard to differences between these and the adults of the same species. During the first month of life occur the main cardiocirculation adaptations that allow individuals to reach adulthood. This literature review aims to discuss some of the main methods of evaluation of the cardiovascular system of ovine neonate, considering the electrocardiogram, echodopplercardiogram, chest radiographic examination and systemic arterial pressure as the main procedures to be important diagnostic methods, mainly used to detect not only the heart changes as also for analysis of the normal function of the heart.(AU)

Para que um problema seja relatado como patologia em um sistema orgânico é necessário que ele seja analisado e comparado ao padrão de normalidade. Poucos estudos relatam esse padrão no sistema cardiovascular de ovinos recém-nascidos deixando uma lacuna no que diz respeito às diferenças entre neonatos e os adultos. Durante o primeiro mês de vida ocorrem as principais adaptações cardiocirculatórias que permitirão ao indivíduo chegar à vida adulta. A presente revisão de literatura tem por objetivo discorrer sobre alguns dos principais métodos de avaliação cardiovascular do neonato ovino, considerando o eletrocardiograma, o ecodopplercardiograma, o exame radiográfico torácico e a pressão arterial sistêmica, como os principais procedimentos, por serem métodos diagnósticos importantes, utilizados principalmente para a detecção não somente das alterações cardíacas como, também, para análise da função normal do coração.(AU)

Evaluación cardiovascular del recién nacido ovino: revisión de literatura / Evaluation of the cardiovascular system of ovine neonate: review of the literature / Avaliação cardiovascular do neonato ovino: revisão de literatura

Así que un problema se divulga como patología en un sistema orgánico es necesaria que sea revisado y Comparado con el normal. Pocos estudios han informado de este patrón en el sistema cardiovascular del recién nacidos ovejas dejando un espacio con respecto a las diferencias entre recién nacidos y adultos. Durante el primer mes de vida se producen las cardiocirculatórias principales adaptaciones que permiten a los individuos llegar a la edad adulta. De esta revisión de literatura pretende discutir algunos de los principales métodos de evaluación cardiovasculares de ovínos recién nacidos, teniendo en cuenta el electrocardiograma, ecodopplercardiogram, examen radiográfico de tórax y la presión arterial sistémica, como los principales procedimientos, porque son métodos de diagnóstico importantes, utilizados principalmente para detectar no sólo los cambios del corazón como también para el análisis de la función normal del corazón.

To report a problem like as pathologic in an organic system is necessary for it to be reviewed and compared to standard. Few studies have reported this pattern in the cardiac system of newborn sheep leaving a gap with regard to differences between these and the adults of the same species. During the first month of life occur the main cardiocirculation adaptations that allow individuals to reach adulthood. This literature review aims to discuss some of the main methods of evaluation of the cardiovascular system of ovine neonate, considering the electrocardiogram, echodopplercardiogram, chest radiographic examination and systemic arterial pressure as the main procedures to be important diagnostic methods, mainly used to detect not only the heart changes as also for analysis of the normal function of the heart.

Para que um problema seja relatado como patologia em um sistema orgânico é necessário que ele seja analisado e comparado ao padrão de normalidade. Poucos estudos relatam esse padrão no sistema cardiovascular de ovinos recém-nascidos deixando uma lacuna no que diz respeito às diferenças entre neonatos e os adultos. Durante o primeiro mês de vida ocorrem as principais adaptações cardiocirculatórias que permitirão ao indivíduo chegar à vida adulta. A presente revisão de literatura tem por objetivo discorrer sobre alguns dos principais métodos de avaliação cardiovascular do neonato ovino, considerando o eletrocardiograma, o ecodopplercardiograma, o exame radiográfico torácico e a pressão arterial sistêmica, como os principais procedimentos, por serem métodos diagnósticos importantes, utilizados principalmente para a detecção não somente das alterações cardíacas como, também, para análise da função normal do coração.

Use of total venous inflow occlusion to enable correction of an atrial septal defect in a dog

Background: Atrial septal defects are generally classified into three types: ostium secundum, ostium primum, and sinus venosus. Diagnose is normaly confirmed with Doppler echocardiography, which can identify and classify atrial septal defects types. This cardiac anomaly may be corrected by different surgical approaches, such as cardiopulmonary bypass or transvenous approaches. Therefore, we chose to close the atrial septal defect using a total venous inflow occlusion technique (TIVO), which has been successfully used in other procedures without major postoperative complications, and are notably cheaper and requires no specialized equipment, been able to be done in different places.Case: An American Pit Bull Terrier was referred to our surgical service for ostium secundum atrial septal defect correction, by the time of surgery the patient presented dyspneic; normal capillary refill time and rectal temperature; the owner mentioned the patient exhibited exercise intolerance and delayed development compared to other dogs of the same age or from the same litter. Cardiac auscultation revealed a systolic murmur at the left base, femoral pulse was normokinetic, and patient was emaciated and prostrated at the time of clinical evaluation. Atrial septal defect was suspected and then confirmed by Doppler echocardiography that revealed a discontinuous area in the interatrial septum, and by color doppler images an aliased signal, that extended through the interatrial septum and shunted from the left to the right atria, was visualized, confirming an ostium secundum atrial septal defect. After a right intercostal thoracotomy, a subphrenic pericardiectomy was performed to provide access to the heart. Cranial and caudal vena cava as well as the azygos vein, were dissected, which allowed placement of a Satinsky’s clamp to proceed with TIVO. Before TIVO initiation, a pursestring suture with 3-0 polypropylene was applied to the right atrium.[...]

Use of total venous inflow occlusion to enable correction of an atrial septal defect in a dog

Background: Atrial septal defects are generally classified into three types: ostium secundum, ostium primum, and sinus venosus. Diagnose is normaly confirmed with Doppler echocardiography, which can identify and classify atrial septal defects types. This cardiac anomaly may be corrected by different surgical approaches, such as cardiopulmonary bypass or transvenous approaches. Therefore, we chose to close the atrial septal defect using a total venous inflow occlusion technique (TIVO), which has been successfully used in other procedures without major postoperative complications, and are notably cheaper and requires no specialized equipment, been able to be done in different places.Case: An American Pit Bull Terrier was referred to our surgical service for ostium secundum atrial septal defect correction, by the time of surgery the patient presented dyspneic; normal capillary refill time and rectal temperature; the owner mentioned the patient exhibited exercise intolerance and delayed development compared to other dogs of the same age or from the same litter. Cardiac auscultation revealed a systolic murmur at the left base, femoral pulse was normokinetic, and patient was emaciated and prostrated at the time of clinical evaluation. Atrial septal defect was suspected and then confirmed by Doppler echocardiography that revealed a discontinuous area in the interatrial septum, and by color doppler images an aliased signal, that extended through the interatrial septum and shunted from the left to the right atria, was visualized, confirming an ostium secundum atrial septal defect. After a right intercostal thoracotomy, a subphrenic pericardiectomy was performed to provide access to the heart. Cranial and caudal vena cava as well as the azygos vein, were dissected, which allowed placement of a Satinskys clamp to proceed with TIVO. Before TIVO initiation, a pursestring suture with 3-0 polypropylene was applied to the right atrium.[...](AU)

Standard strain and strain rate by two-dimensional speckle tracking in agoutis (Dasyprocta prymnolopha) anesthetized with ketamine and xylazine

Background: The agouti (Dasyprocta prymnolopha, Wagler, 1831) is a wild rodent widely found throughout America which has stood out as a good animal model for scientific investigations. The aim of this study was to study the cardiovascular function of chemically contained agoutis, by performing echocardiographic examinations and measuring Strain and Strain Rate by Speckle Tracking to obtain reference values for the species and verify the applicability of these animals as models for the study of cardiovascular changes in humans.Materials, Methods & Results: It was selected 16 animals, sedated by the combination of ketamine hydrochloride and xylazine and submitted to transthoracic echocardiography. To obtain the standard measurements, B, M and Doppler mode images were taken. The analysis of the radial and longitudinal myocardial deformation of the left ventricle was carried out. The right parasternal window was used for access to the short cardiac axis and the left for access to the long axis. Six radial profiles of strain (ST) and Strain rate (SR) values were obtained, corresponding to the mean of the values for each segment. A total of 18 myocardial segments were analyzed for each specimen and the mean values were used to compose the statistical analysis. The comparison of the means between the genders did not show statistical difference, being the other statistical treatments based on the total sample of 16 animals. The variables that showed statistically significant correlation coefficients in relation to weight were: LA, LA/AO, HR, AVmax, E’ wave, E/IVRT (P > 0.05). HR showed a positive correlation with IVSd (r = 0.51), EPSS (r = 0.55) and E’ wave (r = 0.68); negative with IVRT (r = - 0.41), A wave (r = - 0.54), AVmax (r = - 0.53) and Pmax (r = - 0.65).[...]

Standard strain and strain rate by two-dimensional speckle tracking in agoutis (Dasyprocta prymnolopha) anesthetized with ketamine and xylazine

Background: The agouti (Dasyprocta prymnolopha, Wagler, 1831) is a wild rodent widely found throughout America which has stood out as a good animal model for scientific investigations. The aim of this study was to study the cardiovascular function of chemically contained agoutis, by performing echocardiographic examinations and measuring Strain and Strain Rate by Speckle Tracking to obtain reference values for the species and verify the applicability of these animals as models for the study of cardiovascular changes in humans.Materials, Methods & Results: It was selected 16 animals, sedated by the combination of ketamine hydrochloride and xylazine and submitted to transthoracic echocardiography. To obtain the standard measurements, B, M and Doppler mode images were taken. The analysis of the radial and longitudinal myocardial deformation of the left ventricle was carried out. The right parasternal window was used for access to the short cardiac axis and the left for access to the long axis. Six radial profiles of strain (ST) and Strain rate (SR) values were obtained, corresponding to the mean of the values for each segment. A total of 18 myocardial segments were analyzed for each specimen and the mean values were used to compose the statistical analysis. The comparison of the means between the genders did not show statistical difference, being the other statistical treatments based on the total sample of 16 animals. The variables that showed statistically significant correlation coefficients in relation to weight were: LA, LA/AO, HR, AVmax, E wave, E/IVRT (P > 0.05). HR showed a positive correlation with IVSd (r = 0.51), EPSS (r = 0.55) and E wave (r = 0.68); negative with IVRT (r = - 0.41), A wave (r = - 0.54), AVmax (r = - 0.53) and Pmax (r = - 0.65).[...](AU)

Correlation between systolic function and presence of myofibroblasts in doxorubicin-induced cardiomyopathy / Correlação entre função sistólica e presença de miofibroblastos na cardiomiopatia induzida pela doxorrubicina

Cardiotoxicity induced by doroxubicin generates systolic disfunction and myocardial remodeling with presence of myofibroblasts. These cells are thought to be attracted to the injured heart to avoid the development of congestive heart failure. The objective of this study was to evaluate the systolic dysfunction generated by doxorubicin through Doppler echocardiography, and its correlation with the presence of myofibroblasts in the myocardium. Twenty-five New Zealand White rabbits were divided into two groups (control, and treated with doxorubicin). The drug was administered for six weeks; Doppler echocardiography was performed before the first, and after the last administration of doxorubicin. Immuno detection of myofibroblasts was performed by immunohistochemistry. The treated group exhibited significant reduction in systolic function as assessed by Doppler echocardiography, and increased frequency of myofibroblasts, which were present in similar amounts in the left ventricle, interventricular septum, and right ventricle. There was a significant negative correlation between number of myofibroblasts in the interventricular septum and in the left ventricle with systolic function indices, which reveals that the higher the number of fibroblasts, the worst systolic function is in rabbits treated with doxorubicin. Increase in myofibroblast numbers was not sufficient to preserve systolic function.(AU)

A cardiotoxicidade induzida pela doxorrubicina gera disfunção sistólica e remodelamento miocárdico, com presença de miofibroblastos. Acredita-se que essas células sejam atraídas para a não evolução do quadro de insuficiência cardíaca congestiva. O objetivo do presente trabalho foi avaliar a função sistólica gerada pela doxorrubicina por meio da ecodopplercadiografia e correlacioná-la com a presença de miofibroblastos no miocárdio. Foram utilizados 25 coelhos da raça Nova Zelândia, alocados em dois grupos (controle e tratados com doxorrubicina). O fármaco foi administrado por seis semanas e a ecodopplercardiografia foi realizada no momento zero e após a última administração da doxorrubicina. A imunodetecção dos miofibroblastos foi realizada por imuno-histoquímica. Houve redução significativa na função sistólica, observada na ecodopplercardiografia e aumento na imundetecção dos miofibroblastos nos animais tratados, na mesma intensidade no ventrículo esquerdo, septo interventricular e ventrículo direito. Houve correlação negativa significativa entre o número de miofibroblastos no septo interventricular e no ventrículo esquerdo com os índices de função sistólica, revelando que quanto mais miofibroblastos presentes, pior é a função sistólica de coelhos tratados com doxorrubicina. O aumento do número de miofibroblastos não foi suficiente para manutenção da função sistólica.(AU)

Measurement of blood pressure by digital palpation of the peripheral pulse in anesthetized dogs / Mensuração da pressão arterial por palpação digital do pulso periférico em cães anestesiados

The present study aimed to determine the accuracy of measurement of blood pressure (BP) by digital palpation of peripheral pulse (indirect method) in anesthetized dogs. Indirect determination of BP was performed using a sphygmomanometer and a cuff placed proximal to carpus and BP was defined as the value recorded by sphygmomanometer at the time that digital palpation of the pulse in metacarpal artery returned after occlusion and subsequent gradual cuff deflation. Blood pressure was measured simultaneously by invasive (direct) method. Data were compared by Bland Altman analysis to verify the agreement between methods. A total of 131, 65 and 56 observations were performed in 31 dogs during normotension, hypotension and hypertension, respectively. During hypotension, normotension and hypertension, values of bias for systolic arterial pressure (SAP) between methods were respectively - 2, 8 and 12 mmHg, demonstrating underestimation of SAP by the indirect method during normotension and hypertension. Percentages of differences between methods for SAP that were 10 e 20 mmHg were: hypotension, 49 and 88%; normotension, 47 and 79%; hypertension, 25 and 52%. For determination of SAP in dogs, indirect method reported here have lower agreement with the invasive method compared with Doppler and similar to many oscillometric monitors reported in the literature, but do not meet the requirements established by the ACVIM. Use of digital palpation of peripheral pulse for monitoring blood pressure during anesthesia in dogs requires further studies to more accurately determine the accuracy of this method

Com o presente estudo, buscou-se determinar a acurácia da aferição da pressão arterial (PA) pela palpação digital do pulso periférico (método indireto) em cães anestesiados. A determinação indireta da PA foi realizada com auxílio de manguito e esfigmomanômetro posicionados proximais ao carpo e o valor da PA foi considerado aquele registrado pelo esfigmomanômetro no momento em que a palpação do pulso retornava na artéria metacarpiana após a oclusão e subsequente desinsuflação gradual do manguito. A PA foi mensurada simultaneamente pelo método invasivo (direto). Os dados foram comparados pela análise de Bland Altman para verificar a concordância entre os métodos. Foram realizadas 131, 65 e 56 observações em 31 cães, respectivamente em normotensão, hipotensão e hipertensão. Durante a normotensão, hipotensão e hipertensão, os valores do viés para a pressão arterial sistólica (PAS) entre os métodos foram respectivamente 8, -2 e 12 mmHg, demonstrando subestimação desta variável pelo método indireto na normotensão e hipertensão. Para a PAS, as diferenças entre os métodos que constituíram 10 e 20 mmHg foram respectivamente: hipotensão, 49 e 88%; normotensão, 47 e 79%; hipertensão, 25 e 52%. Quando utilizado para a determinação da PAS em cães, o método de palpação digital do pulso periférico apresenta concordância inferior com o método invasivo em relação ao Doppler e similar em relação à PAS mensurada por diversos monitores oscilométricos relatados na literatura, mas não cumpre as exigências estabelecidas pelo CAMIV. O uso do método de palpação do pulso periférico para a monitoração da pressão arterial em cães durante a anestesia requer outros estudos para determinar com maior precisão a acurácia desse método