Cranial vena caval syndrome secondary to transvenous pacemaker implantation in two dogs

Superior vena caval syndrome is a rare, but reported complication of transvenous pacemaker implantation in humans. This syndrome can occur secondary to fibrotic and/or thrombotic obstruction of venous blood flow into the right atrium. The therapeutic approach depends on the suspicion of the presence of an active thrombus and may include antithrombotics, angioplasty and/or surgical venoplasty. We describe two dogs that developed severe pleural effusion secondary to stricture formation in the cranial vena cava 4 years after dual chamber transvenous pacemaker implantation. The stenosis was most likely due to fibrosis secondary to the transvenous pacemaker leads. Balloon angioplasty of the lesion resulted in resolution of the pleural effusion in both patients. Balloon angioplasty appears to be a viable therapeutic approach in dogs with cranial vena caval syndrome caused by focal stenotic lesions.     

Survival of 4 dogs with persistent atrial standstill treated by pacemaker implantation

Pacemakers were implanted in 4 client-owned female dogs which had persistent atrial standstill. Three dogs were alive after 14 to 39 months and 1 dog was euthanized after 10.5 years. This report demonstrates that some dogs with persistent atrial standstill can survive for extended time periods.     

Survival time with pacemaker implantation for dogs diagnosed with persistent atrial standstill

Objectives

To evaluate survival time in dogs with persistent atrial standstill after pacemaker implantation and to compare the survival times for cardiac-related vs. non-cardiac deaths. Secondary objectives were to evaluate the effects of breed and the presence of congestive heart failure (CHF) at the time of diagnosis on survival time.

Applications, complications, and outcomes of transvenous pacemaker implantation in 105 dogs (1997-2002)

We reviewed the indications for age and breeds of dogs who received transvenous endocardial artificial pacemaker (AP) implantation (n = 105) and complications and survival thereafter at a single institution over a 6-year period. A third-degree atrioventricular (AV) block (59%) and sick sinus syndrome (SSS; 27%) were the most common indications, along with a high-grade second-degree AV block (9%) and atrial standstill (5%). The most common breeds identified were Labrador Retriever (n = 16; 11 with a third-degree AV block), American Cocker Spaniel (n = 14; 10 with SSS), and Miniature Schnauzer (n = 13; all with SSS). Common presenting complaints were syncope (n = 66) and exercise intolerance or lethargy (n = 25). Half of the dogs (n = 52) had a history of acute onset of clinical signs (<2 weeks). Mean survival time for the 60 dogs who died during the study period was 2.2 years (range, 0.1-5.8 years). Major complications occurred in 13% of dogs and included lead displacement (n = 7), sensing problems that led to syncope (n = 3), infection at the pacemaker site (n = 1), bleeding (n = 1), and ventricular fibrillation during implantation (n = 1; successfully defibrillated). Minor complications occurred in 11 dogs (11%). The success rate of transvenous AP implantation was comparatively high (all dogs survived the first 48 hours), and the complication rate was comparatively low when compared with a previous multicenter study, most likely because of how commonly the procedure was performed and supervisory experience.     

Techniques and complications of pacemaker implantation in four cats.

Pacemakers were successfully implanted in 4 adult and geriatric cats with bradycardia and associated signs. Various implantation techniques were used. Complications developed in 3 of the cats, generally more severe in 2 of the 3 cats in which thoracotomy and celiotomy were performed than in the cat in which a transvenous endocardial pacing technique was used. After surgery, pacemaker functions were reprogrammed noninvasively in 2 cats. All 4 cats survived without syncope for a mean of 33.1 months after surgery.     

Dual-chamber pacemaker implantation via the cephalic vein in healthy equids

The purpose of the present study was to develop a feasible and safe technique for dual-chamber pacemaker implantation in healthy horses. Implantation was performed in a standing, tranquilized horse and in ponies. Atrial and ventricular leads were transvenously inserted through the cephalic vein, and a subcutaneous pacemaker pocket was created between the lateral pectoral groove and the manubrium sterni in 6 equids. Positioning of each lead was guided by echocardiography and by measuring the electrical characteristics of the lead. The implantation procedure lasted about 4 hours in each animal and was well tolerated. In all animals, dual-chamber pacemaker function was obtained, and these results remained good throughout the follow-up period. At the time of implantation, atrial and ventricular sensing were between 2.1 and 7.2 mV and 7.8 and 16.8 mV, respectively, and atrial and ventricular pacing thresholds at 0.5 millisecond varied from 0.5 to 0.7 V and from 0.3 to 1.0 V, respectively. Six months after the implantation, sensing values varied from 2 to 10 mV for the atrial lead and from 2 to 16 mV for the ventricular lead, while pacing thresholds at 0.5 millisecond varied from less than 0.5 to 2.5 V for the right atrium and from less than 0.5 to 5.0 V for the right ventricle. Atrial lead dislodgment occurred in 2 animals, requiring insertion of a new lead. Ventricular lead dislodgment was not observed.     

Adams-Stokes syndrome and therapy with pacemaker implantation in a dog

Case report concerning therapeutic pacemaker implantation in a 3 year old West-Highland-White terrier with Adams-Stokes syncopes. EKG's, X-ray-pictures, illustrations of the pulse rate and quality and oxygen measurements with a "Pulsoximeter" before and during surgery are shown. A special place takes the report of selection and control of the anesthesia in this case of a special operation. 17 references and 11 pictures.     

Sebaceous adenitis in Swedish dogs,a retrospective study of 104 cases

Background

Sebaceous adenitis (SA) is an uncommon, immune mediated skin disease in dogs. The aim was to retrospectively investigate SA in dogs in Sweden with respect to breed, sex and age distribution. A second aim was to retrospectively compare clinical signs in dogs with generalized SA and to estimate the survival after diagnosis in the English springer spaniel, standard poodle and the akita.

Methods

In total 34 Swedish veterinarians contributed with 104 clinically and histologically verified SA cases. Breed, gender and age at diagnosis were registered for each case. The degree of clinical signs at time for diagnosis and at follow-up and information about treatments, concurrent diseases and euthanasia were recorded for the springer spaniels, standard poodles and akitas using a standardized questionnaire.

Results

A total of 104 cases of SA were included; most cases were recorded for the springer spaniel (n = 25), standard poodle (n = 21) and the akita (n = 10). These three breeds, together with the lhasa apso and the chow-chow, were the most common when national registry data from the Swedish Board of Agriculture and Swedish Kennel Club were considered. The mean age at diagnosis was 4.8 years. The proportion of males was 61%. When the springer spaniels, standard poodles and the akitas with generalized signs were compared (n = 51), the spaniels showed significantly more severe clinical signs than the poodles at diagnosis regarding alopecia, seborrhoea, pyoderma and the overall severity of clinical signs. At follow-up, the degree of clinical signs for otitis externa and pyoderma differed significantly between the breeds. The estimated median survival time was 42 months.In dogs where data regarding survival was available at the end of the study (n = 44), SA was reported to be the reason for euthanasia in 14 dogs, whereof 7 within 24 months after diagnosis.

Conclusion

The result of this study implicates that the English springer spaniel is a breed predisposed to SA and that it has more severe clinical signs than the standard poodle. A large proportion of the dogs (spaniel, poodle and akita) investigated regarding survival were reported to have been euthanized to great extent due to the disease.     

Sick sinus syndrome in a dog: Treatment with dual-chambered pacemaker implantation

A 2-year-old male castrated boxer dog was presented because of a history of syncope. Electrocardiogram tracings obtained with a cardiac event monitor showed bradycardia culminating in asystole. Sick sinus syndrome was diagnosed and treated with transvenous implantation of a dual-chambered permanent pacemaker.     

Pyloric obstruction secondary to epicardial pacemaker implantation: a case report

A 10-year old Lhasa Apso dog was presented for an acute history of exercise intolerance and hind limb weakness. High grade second degree atrioventricular block with an atrial rate of 200 beats per minute, ventricular rate of 40 beats per minute and an intermittent ventricular escape rhythm, was diagnosed on electrocardiograph. A transdiaphragmatic, unipolar, epicardial pacemaker was implanted without immediate surgical complications. Severe vomiting was noted 12 h post-operatively. Abdominal ultrasound and a barium study supported a diagnosis of pyloric outflow obstruction and exploratory abdominal surgery was performed. The pyloric outflow tract appeared normal and no other causes of an outflow obstruction were identified. The epicardial generator was repositioned from the right to the left abdominal wall. Pyloric cell pacing was presumed to be the cause for the pyloric obstruction and severe vomiting, and this was thought to be due to close proximity of the pacemaker generator to the pylorus situated in the right abdominal wall. Repositioning of the pulse generator to the left abdominal wall resulted in resolution of vomiting.     

Permanent transvenous pacemaker implantation in an Ibizan hound cross with persistent atrial standstill

An Ibizan hound cross was referred with a 1-year history of syncope and exercise intolerance. An electrocardiogram showed bradycardia and no P waves; atrial standstill was diagnosed. A permanent artificial endocardial pacemaker was implanted. The lead dislodged and was reimplanted into the right ventricular apex. Capture was once again achieved.     

Results of surgical excision of perianal fistulas in dogs

Eighty-seven dogs that had perianal fistulas diagnosed at the Veterinary Medical Teaching Hospital, University of California, Davis, were treated by excision of the diseased tissues and bilateral anal sacculectomy. Males were affected more often than females (66 to 21), and the German Shepherd Dog was the predominant breed (59 of 87). Information from owners regarding long-term postoperative progress was available for 41 dogs. Twenty-two of the 41 dogs had been euthanatized, 15 (36.6%) because of complications related to perianal fistulas and 7 because of unrelated causes. The mean postoperative period, ie, from the time of surgery to the time of euthanasia, was 34.7 months (range, 1 to 82 months). The remaining 19 dogs were examined after a mean postoperative period of 42.3 months (range, 13 to 100 months). Postoperative complications included development of clinically evident fistulas in 23 of the 41 dogs (56.1%), lack of normal continence (26.8%), tenesmus (19.5%), flatulence (17.1%), and anal stricture (14.6%). Twenty-one of the 41 dogs (51.2%) were judged by their owners to be satisfactory pets or to have been satisfactory pets before euthanasia for unrelated reasons     

Results of thoracic duct ligation in dogs with chylothorax

Thoracic duct lymphangiography and ligation were done on 15 dogs with idiopathic chylothorax. Lymphangiography revealed thoracic lymphangiectasia in all dogs; none had a thoracic duct rupture. Lymphangiography immediately after ligation demonstrated missed branches of the thoracic duct in 4 of the 15 dogs. Eleven of the 15 dogs are alive and doing well. Eight of the 11 had no radiographic or clinical signs of pleural effusion (mean follow-up, 31.5 months; range, 4 to 75 months). The other 3 living dogs had persistent effusion; 2 were successfully managed with a pleuroperitoneal shunt (follow-up, 15 months) or pleurodesis (follow-up, 5 months), respectively, and 1 was not treated because the effusion was mild and the dog did not have clinical signs of disease (follow-up, 14 months). Four of the 15 dogs died or were euthanatized because of persistent effusion (mean follow-up, 11.5 months; range, 3 to 24 months). Considering the lack of treatment alternatives for dogs with idiopathic chylothorax, these results support thoracic duct ligation as a treatment method for dogs.     

Effects of gelatin sponge implantation in cancellous bone defects in dogs

Reports from oral surgeons suggested that packing bone defects with cellulose or collagen stimulated cancellous bone replacement. The study reported here was designed to evaluate a similar method for augmenting the remodeling of cancellous bone defects and graft donor sites. Gelatin sponge was implanted into bony defects created in the proximal humeral metaphysis of 5 adult Beagles after collection of cancellous bone. A similar defect created in the contralateral humerus was left unpacked. Four months after creation of the defect, the dogs were euthanatized, and the surgical sites were evaluated by use of correlated microradiographic and histologic examination. Unpacked sites had filled completely with loosely woven trabecular bone. Remodeling had not taken place in sites packed with gelatin sponge. Gelatin sponge did not elicit any reaction in the surrounding bone, but remained in situ and obstructed new bone formation. Gelatin sponge blocked rather than augmented cancellous bone replacement.     

Clinical investigation of local implantation of gentamicin-impregnated collagen sponges in dogs

The purpose of this study was to evaluate the effects on health and kidney function of local implantation of commercial gentamicin-impregnated collagen sponges. Four healthy dogs were submitted to local surgical implantation of collagen impregnated sponges. Follow-up with serial physical examinations and measurements of serum creatinine, urea nitrogen, and gentamicin were performed for 7 d. There were no adverse reactions, or changes in measurements of kidney function.     

Pacemaker implantation in dogs: results of the last 30 years

Pacemaker implantation in veterinary practice is still not well known and remains uncommon. However, this technique is the only possible way to cure animals suffering from symptomatic bradycardia whose state does not improve with a medical treatment. In most cases, the use of pacemakers in veterinary medicine leads to the disappearance of the clinical and electrocardiographic signs. This retrospective study concerning the last 30 years draws up an evaluation of the improvements, advantages and drawbacks of this method. Moreover, this study allows the understanding of the evolution of pacemakers' use in veterinary cardiology.     

Results of allergen-specific immunotherapy in 117 dogs with atopic dermatitis

The success of the treatment of 117 dogs with atopic dermatitis with allergen-specific immunotherapy for up to 48 months was assessed. An excellent response (remission with exclusive immunotherapy) was recorded in 18 of the dogs, a good response (more than 50 per cent reduction in medication and improvement of clinical signs) was recorded in 57, a moderate response was recorded in 24 and a poor response in 18. The mould antigens in the allergen extract were stored in a separate vial before administration and the success rate of the immunotherapy including mould antigens was much higher than in an earlier study in which mould and pollen antigens had been stored in one vial. The success rate was not affected significantly by the age of the dogs when the disease developed, or by their age or the period for which they had shown clinical signs when the treatment began; it was also unaffected by whether pollens, moulds or dust mites were used as antigens, or by whether the offending allergens had been identified by intradermal testing or by serum testing for allergen-specific immunoglobulin E.     

Results of ancillary tests for respiratory disease in normal dogs

Twenty-five mixed-breed clinically normal mature dogs were evaluated for respiratory disease by thoracic radiographs, complete blood counts, modified Knott's test, fluorescent antibody test for heartworms, bronchoscopy, tracheal washing, and bronchial brushing. Gross necropsies, cultures of lung parenchyma, and microscopic studies of lung at the site of and adjacent to the tracheal washing and bronchial brushing techniques were performed. The high prevalence of abnormal findings reflected subclinical disease in a confined population. The importance of a combination of complementary diagnostic tests was reinforced by the lack of specificity of individual tests.