Clinical presentation, echocardiographic findings, treatment strategies, and prognosis of dogs with myxomatous mitral valve disease presented with pericardial effusion due to suspected left atrial tear: a retrospective case-control study.

INTRODUCTION/OBJECTIVES: Left atrial tear (LAT) is a life-threatening complication in dogs with myxomatous mitral valve disease (MMVD). The study objective was to describe clinical presentation, echocardiographic findings, treatment strategies, and survival in dogs with LAT compared to a control group of dogs with a similar stage of MMVD but no LAT. ANIMALS AND MATERIALS AND METHODS: Two-center retrospective case-controlled study including 15 dogs with and 15 dogs without LAT was conducted. Clinical and echocardiographic data were reviewed, and survival information were collected. RESULTS: Nine dogs in each group were in stage C of MMVD, while the remaining were in stage B2. No differences between groups were found regarding age, body weight, sex, kidney values, and echocardiography-derived cardiac dimensions. Most reported clinical signs associated with LAT included weakness, respiratory signs, and syncope. Treatment varied and was mainly focused on the management of congestive heart failure. Three dogs with LAT received a pericardiocentesis. All 15 dogs with LAT had died of cardiac causes, five dogs during the first seven days after admission. The median survival time for all 15 dogs with LAT was 52 days compared to 336 days in the control group (P=0.103). When excluding five dogs with LAT that died during the first seven days, the median survival increased to 407 days, not different compared to the control group (P=0.549). CONCLUSIONS: Dogs with MMVD and LAT have a high short-term mortality; however, when surviving the acute phase, the long-term prognosis may not differ from dogs with a similarly advanced degree of MMVD but without LAT.

[Treatment of atresia ani type I by balloon dilatation in 5 kittens and one puppy]. / Behandlung von Atresia ani Typ I mittels Ballondilatation bei 5 Katzen- und Einem Hundewelpen.

Atresia ani is the most common anorectal anomaly in small animals. In the present study, an anal stricture (atresia ani type I) in five 3 to 8 weeks old kittens and one 4 month old puppy was treated by balloon dilation. In 4 kittens and the puppy the stricture was eliminated permanently and without complications by a single intervention. Only the smallest kitten with the most severe stenosis developed a rectal fistula as a complication of repeated balloon dilation, which necessitated surgical correction. Balloon dilation proved to be an efficient therapeutic method for anal atresia type I, and can be recommended as the treatment of choice.

[Placement of intraluminal stents for treating tracheal collapse in dogs]. / Implantation intraluminaler Stents zur Behandlung des Trachealkollaps beim Hund.

Tracheal collapse is a progressive disease particularly of small breed dogs. In the terminal stage, when dyspnea becomes the dominating sign and is no longer manageable with medical treatment, a surgical procedure is necessary. With increasing frequency intraluminal tracheal stents are implanted minimal-invasively. In individual animals this is a lifesaving procedure, leading to immediate elimination of dyspnea. In most dogs cough for some time has to be anticipated as the stent acts as a foreign body, but severe complications like excessive formation of granulation tissue, stent migration or stent fracture are rare. Stents represent an attractive treatment modality for tracheal collapse in dogs with dyspnea.

Effect of a single dose of pimobendan on right ventricular and right atrial function in 11 healthy cats.

OBJECTIVES: The objective of this study was to investigate the effect of pimobendan on echocardiographic parameters of right ventricular and atrial function in healthy cats. ANIMALS: Eleven privately owned, healthy adult cats. MATERIAL AND METHODS: Each cat underwent five echocardiographic examinations: the first and second examinations were performed 1 h apart on day 0. On day 1, the third examination served as baseline, whereas the fourth and fifth examinations were performed one and 6 h after administration of a single oral dose of pimobendan (1.25 mg/cat), respectively. Parameters of right ventricular and atrial morphology and function were collected and compared among time points. RESULTS: Pimobendan administration produced a change in some echocardiographic variables. Specifically, heart rate, right ventricular fractional shortening and peak velocity of systolic lateral tricuspid annular motion increased (P = 0.032, P = 0.002 and P < 0.001, respectively), whereas right ventricular end-systolic internal diameter and right atrial maximum and minimum internal diameters decreased (P = 0.004, P = 0.025 and P = 0.01, respectively). Right ventricular fractional area change and tricuspid annular plane systolic excursion did not change. CONCLUSIONS: This novel study showed that pimobendan had positive effects on right ventricular and right atrial function in healthy cats. Further studies are needed to determine whether pimobendan has similar effects in cats with cardiac diseases.

Microbiologic evaluation of gallbladder bile of healthy dogs and dogs with iatrogenic hypercortisolism: a pilot study.

BACKGROUND: In people, hypercortisolism (HC) has been associated with acalculous cholecystitis and biliary dyskinesia, which may potentiate ascending biliary infections. In dogs, an association between HC and gallbladder disease recently has been documented, although the role of bacteria remains controversial. Furthermore, there is no information on the gallbladder bile microbial flora in healthy dogs. OBJECTIVES: To investigate the microbial flora in gallbladder bile in healthy dogs, the relationship between iatrogenic hyperadrenocorticism and bactibilia and possible changes in biliary microbial flora after cortisol withdrawal in dogs. ANIMALS: Six control dogs and 6 dogs treated with hydrocortisone. METHODS: Gallbladder bile obtained by percutaneous ultrasound-guided cholecystocentesis was cultured aerobically and anaerobically and examined cytologically before (d0), during (d28, d56, d84), and after (d28p, d56p, d84p) administration of hydrocortisone (8 mg/kg PO q12h). RESULTS: In the control group, 2/42 bile cultures yielded bacterial growth (Enterococcus sp.; Escherichia coli on d0) and 1/42 bile smears had cytological evidence of bacteria (d28). In the HC group, 2/42 bile cultures yielded bacterial growth (Enterococcus sp. on d28; Bacillus sp. on d28p) and 3/42 bile smears had cytological evidence of bacteria (d84, d84, d28p). All dogs remained healthy throughout the study period (168d). CONCLUSIONS AND CLINICAL IMPORTANCE: Based on the results of conventional bacterial culture techniques, gallbladder bile of healthy dogs periodically may harbor bacteria, which do not appear to be clinically relevant. A 3-month period of iatrogenic HC was not associated with bactibilia. A higher prevalence of bactibilia may be detected with micromolecular techniques.

Pulmonary artery thrombosis in experimental Angiostrongylus vasorum infection does not result in pulmonary hypertension and echocardiographic right ventricular changes.

BACKGROUND: Dogs experimentally inoculated with Angiostrongylus vasorum develop severe pulmonary parenchymal lesions and arterial thrombosis at the time of patency. HYPOTHESIS: A. vasorum-induced thrombosis results in arterial hypoxemia, pulmonary hypertension (PH), and altered cardiac morphology and function. ANIMALS: Six healthy Beagles experimentally inoculated with A. vasorum. METHODS: Thoracic radiographs and arterial blood gas analyses were performed 8 and 13 weeks postinoculation (wpi) and 9 weeks posttherapy (wpt). Echocardiography was done before and 2, 5, 8, 13 wpi and 9 wpt. Invasive pulmonary artery pressure (PAP) measurements were obtained 8 wpi. Two untreated dogs were necropsied 13 wpi and 4 treated dogs 9 wpt. RESULTS: All dogs had patent infections at 7 wpi and clinical respiratory signs at 8 wpi. Moderate hypoxemia (median PaO2 of 73 and 74 mmHg) present at 8 and 13 wpi had resolved by 9 wpt. Echocardiographically, no evidence of PH and no abnormalities in cardiac size and function were discernible at any time point. PAP invasively measured at 8 wpi was not different from that of control dogs. Severe radiographic pulmonary parenchymal and suspected thrombotic lesions at 13 wpi were corroborated by necropsy. Most histopathologic changes had resolved at 9 wpt, but focal inflammatory, thrombotic, and fibrotic changes still were present in all dogs. CONCLUSION: In experimentally infected Beagles, pulmonary and vascular changes induced by A. vasorum are reflected by marked radiographic changes and arterial hypoxemia. These did not result in PH and echocardiographic changes in cardiac size and function.

Closure of an unusual morphology patent ductus arteriosus with a covered stent in a dog.

Patent ductus arteriosus (PDA) with unusual morphology was diagnosed in a 3-year-old German shepherd presented for exercise intolerance. Two interventional PDA closure procedures with various Amplatzer devices and one surgical ligation were attempted to close the PDA. However, PDA closure failed with both methods due to the unusual morphology and the severe enlarged ductus ampulla. Therefore, the patient underwent an aortic covered stent placement, and successful closure of the PDA was achieved. Eight months after the procedure, the dog was free of clinical signs and no residual flow was identified through the PDA on transthoracic echocardiography. Moreover, computed tomography angiography demonstrated correct stent positioning, with no evidence of thrombus formation, damage to the stent, nor any aortic wall abnormalities. Aortic covered stent placement is a viable option in dogs with unusual PDA morphology.

Use of auscultation and Doppler echocardiography in Boxer puppies to predict development of subaortic or pulmonary stenosis.

BACKGROUND: Boxers are predisposed to subaortic and pulmonic stenosis (SAS, PS). Screening of puppies may be useful in estimating the risk of their developing a defect that potentially compromises life expectancy or exercise tolerance. HYPOTHESIS: Presence of SAS or PS in adult Boxers can be predicted by auscultation and Doppler echocardiography at 9-10 weeks of age. ANIMALS: Eighty-five Boxer puppies examined at 9-10 weeks of age and at 12 months of age. METHODS: Prospective, longitudinal observational study. Auscultation by stethoscope and continuous wave-Doppler echocardiography for peak velocities (V(max)) in the aorta (Ao) and pulmonary artery (PA). RESULTS: Intensity of heart murmurs in puppies correlated with V(max)Ao and V(max)PA in adults. V(max)Ao and V(max)PA in puppies correlated with V(max)Ao and V(max)PA in adults, respectively. From puppy to adult, V(max)Ao increased and V(max)PA remained unchanged. The negative predictive value for absent or only a soft (< or =II/VI) murmur in puppies being associated with V(max)Ao and PA < or = 2.4 m/s as an adult was 90% and < or =3.5 m/s 100%. The negative predictive value of a V(max)< or = 2.4 m/s as a puppy still being < or =2.4 m/s as an adult was 94% for Ao and 96% for PA, and of a V(max)< or = 3.5 m/s, 99% for Ao and 100% for PA. CONCLUSIONS AND CLINICAL IMPORTANCE: Even though V(max)Ao increases during growth in Boxer puppies, indicating relative narrowing of the aorta, puppies with V(max)Ao < or = 2.4 m/s do not usually progress to clinically have relevant SAS at 12 months of age.

Pancreatitis associated with clomipramine administration in a dog.

A three-year-old, male, entire, Yorkshire terrier was presented with peracute onset of abdominal pain and vomitus. Clinicopathological abnormalities included severely increased serum lipase activity, immeasurably high serum trypsin-like immunoreactivity and mild hypocalcaemia. Canine pancreatic lipase immunoreactivity (cPLI) was intended to be measured, however, the sample got lost. Ultrasonography revealed a hypoechoic pancreas with small amounts of peripancreatic fluid and hyperechogenic mesentery. Acute pancreatitis (AP) was diagnosed and the dog recovered with appropriate therapy within 48 hours. Clomipramine, a selective serotonin reuptake inhibitor (SSRI) for alleviating signs of separation anxiety had been given for seven weeks. Two similar, albeit less severe, episodes associated with previous courses of clomipramine had occurred eight months earlier that responded to discontinuing clomipramine and supportive care. As SSRIs are associated with AP in human beings and no other trigger could be identified, we conclude that clomipramine should be considered as a potential cause when investigating causes for AP in susceptible breeds or other dogs presenting with compatible clinical signs.

Holter monitoring demonstrates that ventricular arrhythmias are common in cats with decompensated and compensated hypertrophic cardiomyopathy.

Arrhythmias can complicate cardiac disease in cats and are a potential cause of sudden death. The aim of this study was to evaluate the presence and nature of cardiac arrhythmias, and the potential correlation between plasma serum troponin I (cTnI) concentrations and the presence or severity of arrhythmias in cats with decompensated (dHCM) and compensated hypertrophic cardiomyopathy (cHCM). Forty one client-owned cats were studied: 16 with cHCM, 15 with dHCM and 10 healthy control cats. Physical examination, echocardiography, cTnI and 24-h Holter recordings were obtained in all cats and thoracic radiographs in cats with dHCM. Cats in both HCM groups were followed for 1 year after their initial Holter examination. The median (range) number of ventricular premature complexes (VPCs) over 24h was 867 (1-35,160) in cats with dHCM, 431 (0-18,919) in cats with cHCM and 2 (0-13) in healthy control cats. The median number of episodes of ventricular tachycardia (VTach) was 0 (0-1497) in dHCM and 0.5 (0-91) in cats with cHCM. The number of VPCs, VTach episodes and heart rate was not different between the HCM groups. Plasma serum troponin I was highest in the cats with dHCM, but there was no correlation between cTnI concentration and the number of arrhythmias. Thirteen of 31 cats with HCM died, but an association with the presence and complexity of ventricular arrhythmias was not observed. Compared to healthy cats, ventricular arrhythmias were common in cats with cHCM and dHCM, but neither presence nor complexity of arrhythmias could be linked to prognosis.

The effects of hydrocortisone on systemic arterial blood pressure and urinary protein excretion in dogs.

BACKGROUND: Hypertension and proteinuria are commonly recognized in dogs with spontaneous hypercortisolism. There is, however, little information regarding the effect of exogenous glucocorticoids on blood pressure (BP) and proteinuria and whether these changes are reversible. HYPOTHESIS: Hydrocortisone administration increases systemic BP and urinary protein excretion, and these effects are reversible after hydrocortisone withdrawal. ANIMALS: Six control dogs and 6 dogs treated with hydrocortisone. METHODS: BP, urine protein : creatinine ratio (UPC), microalbuminuria (MALB), urine albumin : creatinine ratio (UAC), and urine gel electrophoresis were evaluated before, during, and after administration of hydrocortisone (8 mg/kg PO q12h for 12 weeks) or placebo. RESULTS: BP and UPC increased substantially during hydrocortisone administration from 123 mmHg (range 114-136 mmHg) and 0.17 (0.15-0.28) to a maximum of 143 mmHg (128-148 mmHg) and 0.38 (0.18-1.78), respectively, on day 28. MALB developed in 4 dogs and UAC significantly increased in all dogs during hydrocortisone administration with the maximum on day 84. Both increases in BP and proteinuria were reversible and completely resolved within 1 month after stopping hydrocortisone administration. SDS-AGE revealed the proteinuria to be primarily albuminuria with a pronounced increase during hydrocortisone treatment. Furthermore, a protein of 25-30 kDa was found in male dogs, identified by mass spectrometry to be arginine esterase, the major secretory prostatic protein. CONCLUSIONS AND CLINICAL IMPORTANCE: Long-term hydrocortisone treatment results in significant but only mild increases in systemic BP and urinary protein excretion, which are both reversible within 1 month after discontinuation of hydrocortisone.

Effect of long-term adaptation on indirect measurements of systolic blood pressure in conscious untrained beagles.

To evaluate the effect of an adaptation period on systemic blood pressure readings, systolic blood pressure was measured in 12 young adult untrained beagles over several weeks by means of a Doppler flow detector and oscillometric devices. The pressure decreased gradually and significantly, and levelled out after 14 days. The median (range) of values obtained by Doppler were 166 (149 to 200) mmHg initially, 145 (119 to 176) mmHg on day 9, 138 (118 to 165) mmHg on day 10, 127 (111 to 139) mmHg on day 35, 124 (115 to 143) mmHg on day 94 and 127 (114 to 142) mmHg on day 161. All the later measurements were significantly lower than the initial measurement. Male dogs had higher blood pressures than females on each occasion. The blood pressure readings obtained with one of the oscillometric devices and the Doppler device were comparable and correlated significantly.

Cats with diabetes mellitus have diastolic dysfunction in the absence of structural heart disease.

Diabetes mellitus (DM) can result in cardiovascular dysfunction and heart failure characterized by diastolic dysfunction with or without the presence of systolic dysfunction in people and laboratory animals. The objective of this prospective study was to determine if cats with newly diagnosed DM had myocardial dysfunction and, if present, whether it would progress if appropriate antidiabetic therapy was commenced. Thirty-two diabetic cats were enrolled and received baseline echocardiographic examination; of these, 15 cats were re-examined after 6 months. Ten healthy age- and weight-matched cats served as controls. Diabetic cats at diagnosis showed decreased diastolic, but not systolic function, when compared to healthy controls, with lower mitral inflow E wave (E) and E/E' than controls. After 6 months, E and E/IVRT' decreased further in diabetic cats compared to the baseline evaluation. After excluding cats whose DM was in remission at 6 months, insulin-dependent diabetic cats had lower E, E/A and E' than controls. When classifying diastolic function according to E/A and E'/A', there was shift towards impaired relaxation patterns at 6 months. All insulin-dependent diabetic cats at 6 months had abnormal diastolic function. These results indicate that DM has similar effects on diastolic function in feline and human diabetics. The dysfunction seemed to progress rather than to normalize after 6 months, despite antidiabetic therapy. In cats with pre-existing heart disease, the development of DM could represent an important additional health risk.

Evaluation of an electrolyte analyser for measurement of concentrations of ionized calcium and magnesium in cats.

The goal of this study was to evaluate the Nova CRT 8 electrolyte analyser for determination of concentrations of ionized calcium (Ca(i)) and magnesium (Mg(i)) in cats, to determine the effects of sample handling and storage and to establish reference ranges. The precision and analytical accuracy of the Nova CRT 8 analyser were good. The concentrations of Ca(i) and Mg(i) were significantly lower in aerobically handled serum samples than in those handled anaerobically. The concentrations of Ca(i) and Mg(i) differed significantly among whole blood, plasma and serum. In anaerobically handled serum, the concentration of Ca(i) was stable for 8 h at 22 degrees C, for 5 days at 4 degrees C and for 1 week at -20 degrees C. The concentration of Mg(i) was stable for 4 h at 22 degrees C but for less than 24 h at 4 degrees C and for less than 1 week at -20 degrees C. In serum from 36 cats, the reference ranges were 1.20-1.35 mmol/L for Ca(i) and 0.47-0.59 mmol/L for Mg(i). The Nova CRT 8 electrolyte analyser is suitable for determination of Ca(i) and Mg(i) concentrations in cats. Anaerobically handled serum samples are recommended and, stored at room temperature, they yield accurate results when analysed within 4 h.

Thyrotropin-releasing hormone stimulation test to assess thyroid function in severely sick cats.

Basal serum thyroxine (T4) concentration and the thyrotropin-releasing hormone (TRH) stimulation test were used to assess thyroid function in 36 critically ill cats examined between July 1996 and October 1998. Of the 36 cats. hyperthyroidism (as underlying or complicating disease) was suspected in 22 based on clinical signs, palpable thyroid nodules, and abnormal thyroid gland histology (study group). Hyperthyroidism was not suspected in the remaining 14 cats, which served as the control group. Based on serum T4 concentrations, suppression of thyroid function was documented in 14 (64%) cats of the study group and in 10 (71%) cats of the control group. The TRH stimulation test revealed an increase in serum T4 of less than 50% of the baseline concentration in 18 (82%) cats of the study group, and in 6 (43%) cats of the control group. In conclusion, based on the results of serum T4 determinations and the TRH stimulation tests, it was not possible to differentiate between cats with clinical and histologic evidence of thyroid dysfunction (hyperthyroidism) and cats with severe nonthyroidal illnesses.

Surgical removal of heartworms from a cat with caval syndrome.

Caval syndrome was diagnosed in a 4-year-old male domestic shorthair cat with severe dyspnea attributable to chylothorax. The diagnosis of heartworm infection was made on the basis of the ultrasonographic detection of a large number of adult heartworms in the right side of the heart and positive results for modified Knott's and heartworm antigen tests. Heartworms were surgically removed through an incision in the jugular vein, using a string-type horsehair brush and an alligator forceps. All clinical signs resolved after the surgery. Although treatment with agents that would kill the adult heartworms was considered, surgical treatment was used on the cat reported here. Surgical treatment may be the method of choice for use in cats with severe or persistent clinical signs attributable to infections with large numbers of heartworms.

Ultrasonography of the parathyroid glands as an aid in differentiation of acute and chronic renal failure in dogs.

OBJECTIVE: To evaluate whether determination of parathyroid gland size by use of ultrasonography is helpful in differentiating acute renal failure (ARF) from chronic renal failure (CRF) in dogs. DESIGN: Prospective study. ANIMALS: 20 dogs with renal failure in which serum creatinine concentration was at least 5 times the upper reference limit. Seven dogs had ARF, and 13 dogs had CRF. Twenty-three healthy dogs were used as controls. PROCEDURE: Dogs were positioned in dorsal recumbency for ultrasonographic examination of the ventral portion of the neck, A 10-MHz linear-array high-resolution transducer was used. The size of the parathyroid gland was determined by measuring the maximal length of the gland on the screen when it was imaged in longitudinal section. For comparison among groups, the longest linear dimension of any of the parathyroid glands of each dog was used. RESULTS: Size of the parathyroid glands in the control dogs varied from 2.0 to 4.6 mm (median, 3.3 mm). In the dogs with ARF, gland size ranged from 2.4 to 4.0 mm (median, 2.7), which was not significantly different from controls. In dogs with CRF, the glands were more distinctly demarcated from the surrounding thyroid tissue, than those of controls and dogs with ARF. Sizes ranged from 3.9 to 8.1 mm (median, 5.7 mm), which was significantly larger, compared with controls and dogs with ARF. CONCLUSIONS AND CLINICAL RELEVANCE: In dogs with severe azotemia, ultrasonographic examination of the parathyroid glands was helpful in differentiating ARF from CRF Size of the parathyroid glands appeared to be related to body weight.

Clinical and pathological characterisation of primary pulmonary hypertension in a dog.

Primary pulmonary hypertension was diagnosed in an eight-year-old labrador retriever on the basis of echocardiographic findings of severe right ventricular eccentric hypertrophy, abnormally high systolic and diastolic pulmonary arterial pressures calculated by applying the modified Bernoulli equation to the tricuspid and pulmonary insufficiency peak velocities, and the absence of any underlying disease known to cause secondary pulmonary hypertension. The clinical abnormalities developed gradually, from exercise intolerance starting early in life to terminal right-sided congestive heart failure. Consistent histopathological findings were severe intimal and medial thickening of small arteries and arterioles that led to vascular obliteration.

Non-invasive measurement of the cardiovascular effects of chronic hypoxaemia on dogs living at moderately high altitude.

Pulmonary hypertension is a well-recognised condition in dogs, and, among other mechanisms, is caused by hypoxia. In order to evaluate the effect of chronic hypobaric hypoxia on pulmonary arterial pressure in dogs, a colony of 19 clinically and biochemically healthy Greenland sled dogs living permanently at at least 2300 m above sea level (altitude dogs) and 10 clinically healthy Greenland sled dogs living at 700 to 900 m above sea level (control dogs) were examined. Investigations were made of the dogs' packed-cell volume, venous and arterial blood gases, electrocardiogram, blood pressure and echocardiograph, including the calculation of pulmonary arterial pressure by Doppler examination of tricuspid regurgitation. The altitude dogs had a marked arterial hypoxaemia with a mean (sd) oxygen partial pressure of 61.9 (7.4) mmHg and a significantly lower arterial oxygen saturation (90.7 [3.7] per cent) than the control dogs (96.7 [0.8] per cent). In eight of the altitude dogs, tricuspid regurgitation allowed calculation of the systolic pulmonary arterial pressure, which was 29.5 (10.4) mmHg. Eight of the control dogs had tricuspid insufficiency, and their derived systolic pulmonary arterial pressure was significantly lower (17.4 [3.9] mmHg).