Evaluation of red cell distribution width in dogs with pulmonary hypertension

ObjectivesTo compare red cell distribution width (RDW) between dogs with different causes of pulmonary hypertension (PH) and a control dog population to determine whether RDW was correlated with severity of PH as measured by echocardiography. A further aim was to determine the prognostic significance of increased RDW for dogs with PH.AnimalsForty-four client-owned dogs with PH and 79 control dogs presented to a single tertiary referral institution.MethodsSignalment, clinical pathological and echocardiographic data were obtained retrospectively from the medical records of dogs with PH, and RDW measured on a Cell-Dyn 3500 was compared between dogs with pre- and post-capillary PH and a control population. Referring veterinary surgeons were contacted for follow-up information and Kaplan–Meier analysis was conducted to investigate differences in survival time between affected dogs with different RDW values.ResultsThe RDW was significantly greater in dogs with pre-capillary PH compared to control dogs. There was no difference in median survival times between dogs with PH divided according to RDW values. The RDW was positively correlated with mean corpuscular volume and haematocrit in dogs with PH, but did not correlate with echocardiographic variables.ConclusionsAn association was found between dogs with PH and increased RDW; however there was considerable overlap in values between control dogs and dogs with PH. The RDW was not associated with survival in this study.     

Can testicular artery Doppler velocimetry values change according to the measured region in dogs?

Testicular tissue maintenance is performed by the testicular artery, and the hemodynamics of this artery can be evaluated using Doppler ultrasonography. The aim of this study was to characterize the peak systolic velocity (PSV), end diastolic velocity (EDV), pulsatility index (PI) and resistivity index (RI) of five regions of the testicular artery in dogs, including two proposed regions and three that have been previously described. Twenty‐two dogs were used, and the PSV, EDV, PI and RI of the testicular artery were measured in five regions: proximal, medial and distal supratesticular; marginal; and intratesticular. The median values for PSV (cm/s), EDV (cm/s), PI and RI in the five regions were as follows: proximal supratesticular (23.1, 3.7, 2.1 and 0.8); medial supratesticular (17.2, 4.5, 1.5, and 0.7); distal supratesticular (12.2, 5.7, 0.8, and 0.5); marginal (11.3, 6.5, 0.5, and 0.4); and intratesticular (5.7, 3.5, 0.5, and 0.4). There was a difference between the PSV of the medial and distal supratesticular regions. There were differences in the PSV, EDV, PI and RI among the distal supratesticular, marginal and intratesticular regions. Measurements of PSV, EDV, PI and RI of the testicular artery in dogs at the proposed regions showed different results due to the hemodynamic and morphological differences of the artery during its course in the spermatic cord and to the testicles. It is necessary to identify the region in testicular artery Doppler velocimetric evaluations of dogs, given that there is a difference according to the region measured.     

正常鸡、亚临床腹水鸡和腹水鸡肺外动脉舒张反应性的比较

采用离体血管环技术比较了正常鸡、亚临床腹水鸡和腹水鸡的离体肺外动脉对乙酰胆碱(ACh)的内皮依赖性和对硝普钠(SNP)的非内皮依赖性舒张反应性。结果显示:在苯肾上腺素(PE)预收缩后,正常鸡、亚临床腹水鸡和腹水鸡的肺外动脉对ACh和SNP均表现出浓度依赖性舒张反应。低ACh和SNP浓度时,三者的舒张反应相差不明显,高浓度时,腹水鸡和亚临床腹水鸡的舒张反应性明显比正常鸡低。3 3×10-6ACh可使正常鸡肺外动脉舒张百分数达100%,亚临床腹水鸡和腹水鸡仅分别为83 12%和80 84%;3 3×10-7SNP使正常鸡肺外动脉舒张百分数达98 17%,亚临床腹水鸡和腹水鸡仅分别为70 46%和71 65%。亚临床腹水鸡和腹水鸡肺外动脉对PE的收缩反应比正常鸡强。结果表明肺动脉高压肉鸡肺外动脉对ACh的内皮依赖性和对SNP的非内皮依赖性舒张反应都下降,对PE的收缩反应性增加。结果初步证明肺外动脉舒张反应性下降及收缩反应性增加与肉鸡肺动脉高压的形成有关。     

Ante-mortem diagnosis of persistent truncus arteriosus in an 8-year-old asymptomatic dog

Persistent truncus arteriosus (PTA) was diagnosed in an 8-year-old neutered male Poodle referred for echocardiographic examination prior to anesthesia for surgical correction of bilateral cataract. A single large artery limited by a bicuspid valve and overriding both ventricles was observed with 2 distinct pulmonary arteries arising from the common arterial trunk. A large size interventricular septal defect was associated with a low velocity bidirectional shunt. The lesion was identified as a Type 3 PTA according to Collett and Edwards' classification. Although no clinical signs were reported, the dog presented polycythemia (packed cell volume = 68%) at the time of diagnosis. To our knowledge, this is the first report of an echocardiographic diagnosis of PTA in the dog. Until now, the ante-mortem diagnosis of this congenital heart disease has only been described in the cat. This case is also of interest because of the age of the animal and the total absence of cardio-respiratory signs at the time of diagnosis.     

低温高能日粮对肉鸡肺动脉和腹水症的影响

本试验用高能日粮饲养１日龄ＡＡ父母代公雏,２１日龄开始用低温估为发病模型诱发肉鸡腹水症,取不同日龄的肉鸡肺脏和肺动脉固定,光镜和电镜观察肺脏组织学变化,用图像分析仪进行肺动脉测定,结果如下：低温组３５日龄时直径５０～１００rm、１００～２００um肺动脉中膜肥大,管腔面积,差异极显著（Ｐ〈０．０１）。外膜下弹力纤维、胶原纤维增多。低温下２８日龄超微结构观察表明肺动脉内皮细胞肿胀、细胞突起消失。随着低温时     

肉鸡腹水症发病机理研究Ⅳ.肉鸡和蛋仔鸡左右心室功能的比较研究

试验选用快速生长的艾维茵肉鸡和海兰蛋仔鸡 ,各试验组用右心导管法和左心导管法测定肺动脉压(PAP)、右心室收缩压 (RVSP)、左心室收缩压 (LVSP)、左右心室内压最大变化速率 (+dp/dt)的动态变化。并且比较了相同体重健康蛋仔鸡、肉鸡的左右心室功能变化特点。结果表明 :相同日龄肉鸡肺动脉压显著高于蛋仔鸡 ;2 8、35日龄肉鸡右心收缩压显著高于蛋仔鸡 (P <0 0 5) ,2 8、35、42和 49日龄肉鸡左心室收缩压低于蛋仔鸡 ,且差异极显著 (P <0 0 1 )。肉鸡左心室内压最大变化速率 (LV +dp/dt)从 2 1日龄测定起呈现显著性低于同日龄的蛋仔鸡。相同体重的肉鸡和蛋鸡相比 ,肉鸡肺动脉压 (PAP)显著高于蛋仔鸡 ,但肉鸡右心室内压最大变化速率 (RV +dp/dt)、左心室收缩压 (LVSP)、左心室内压最大变化速率 (LV +dp/dt)显著低于蛋仔鸡。这提示肉鸡先天存在着肺动脉压较高、左心室病理性功能低下 ,这可能是肉鸡容易发生腹水症的原因之一     

The injury effect of oxygen free radicals in vitro on cultured pulmonary artery endothelial cells from broilers

Pulmonary artery endothelial cells (PAEC) were isolated from broilers by the method of tissue explantation. The cells were identified using morphological features and immunocytochemical staining using a specific antiserum against factor VIII related antigen. Xanthine/Xanthine oxidase (X/XO) served as the oxygen free radical (OFR) generating system. In vitro model of oxidative injury of PAEC was established based on the X/XO system. The effect of OFR on the growth and viability of PAEC was determined with methylthiazol tetrazolium (MTT) colorimetric assay. Malondialdehyde (MDA, a product of lipid peroxidation) in culture medium of PAEC was detected by a thiobarbituric acid colorimetric assay. The results showed that PAEC survive in vitro and can be subcultured for 5-6 passages. Morphological and immunocytochemical observations of cultured cells demonstrated specific characteristics of endothelial cells. PAECs were severely damaged by OFR. The viability of cells was reduced by the X/XO system, and a dose-dependent decrease in cell viability was found with increasing XO dosages. OFR promoted lipid peroxidation of PAEC and increased the MDA concentration in culture media. These results suggest that OFR can injure the endothelial cells from broiler pulmonary arteries in vitro, which confirms previous results obtained in vivo. Oxidative injury may play an important role in the pathogenesis of pulmonary hypertension syndrome in broiler.     

Spectral waveform analysis of major arteries in conscious dogs by Doppler ultrasonography

Normal values of arterial blood flow velocity and waveforms in major arteries of 10 healthy conscious Beagle dogs were determined using Doppler ultrasonography. Peak systolic, early diastolic, and end-diastolic velocities of the basilar artery, common carotid artery, abdominal aorta, external iliac artery, femoral artery, and peak ejection velocity of the valvular aorta were evaluated. Pulsatility index (PI) of the basilar artery and blood pressure were recorded. All arteries had a high-resistance flow pattern with triphasic flow velocity except the basilar artery, which had a low-resistance pattern. Mean peak systolic velocities of the basilar artery, common carotid artery, abdominal aorta, external iliac artery, and femoral artery were 72 +/- 19, 115 +/- 17, 121 +/- 24, 105 +/- 25, and 110 +/- 17 cm/s, respectively. The PI of the basilar artery and peak ejection velocity of the valvular aorta were 1.37 +/- 0.13 and 96 +/- 16 cm/s, respectively. Mean systolic and diastolic blood pressures were 137 +/- 13 and 78 +/- 15 mmHg, respectively. Present findings may be used as references in future studies on vascular diseases and hemodynamics in dogs.     

Echocardiographic assessment of coronary artery flow in normal canines and model dogs with myocardial infarction

This study was conducted to evaluate the usefulness of coronary arterial profiles from normal dogs (11 animals) and canines (six dogs) with experimental myocardial infarction (MI) induced by ligation of the left coronary artery (LCA). Blood velocity of the LCA and right coronary artery (RCA) were evaluated following transthoracic pulsed-wave Doppler echocardiography. The LCA was observed as an infundibular shape, located adjacent to the sinus of Valsalva. The RCA appeared as a tubular structure located 12 o''clock relative to the aorta. In normal dogs, the LCA and RCA mean peak diastolic velocities were 20.84 ± 3.24 and 19.47 ± 2.67 cm/sec, respectively. The LCA and RCA mean diastolic deceleration times were 0.91 ± 0.14 sec and 1.13 ± 0.20 sec, respectively. In dogs with MI, the LCA had significantly (p < 0.01) lower peak velocities (14.82 ± 1.61 cm/sec) than the RCA (31.61 ± 2.34 cm/sec). The RCA had a significantly (p < 0.01) rapid diastolic deceleration time (0.71 ± 0.06 sec) than that found in the LCA (1.02 ± 0.22 sec) of MI dogs. In conclusion, these profiles may serve as a differential factor for evaluating cardiomyopathy in dogs.