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.

Survie de 4 chiennes atteintes de paralysie auriculaire persistante traitées à l'aide de l'implantation d'un cardiostimulateur. Des cardiostimulateurs ont été implantés chez 4 chiennes, appartenant à des propriétaires, atteintes de paralysie auriculaire persistante. Trois chiennes étaient vivantes après 14 à 39 mois et 1 chienne a été euthanasiée après 10,5 ans. Ce rapport démontre que certains chiens atteints de paralysie auriculaire persistante peuvent survivre pendant des périodes de temps prolongées.(Traduit par Isabelle Vallières).

Evaluation of extended-release diltiazem once daily for cats with hypertrophic cardiomyopathy.

Serum diltiazem concentrations were evaluated following either 30 mg or 60 mg of an extended-release diltiazem administered orally once daily to 13 cats. Sequential blood samples were obtained over 24 hours. Both dosages usually resulted in elevated serum concentrations of >200 ng/mL at 6, 12, 18, and 24 hours. The 30-mg dosage was sometimes associated with low serum concentrations of <50 ng/mL at 18 and 24 hours. The 60-mg dosage (9.3 to 14.8 mg/kg) was associated with lethargy, gastrointestinal disturbances, and weight loss in nine (36%) of 25 client-owned cats. Gastrointestinal disturbances were recognized within 1 week, and weight loss was detected after 2 to 6 months of treatment.

Pulmonary edema secondary to a cardiac schwannoma in a dog.

A 4-year-old castrated labrador retriever presented for cardiac evaluation to determine the etiology of cardiogenic pulmonary edema diagnosed 1 month prior. A large pedunculated mass involving the ventral aspect of the mural mitral valve leaflet and the endocardial surface of the left ventricular free wall, resulting in severe mitral regurgitation, was identified on echocardiogram. Histopathology and immunohistochemistry of this mass and other endocardial masses identified at necropsy for S-100 protein were consistent with a diagnosis of schwannoma. To the authors' knowledge, this is the first case of a benign intracardiac schwannoma described in the left heart of a dog.

Doppler echocardiographic diagnosis and surgical therapy of constrictive pericarditis in a cat.

A 4-year-old Ragdoll cat presented for dyspnea secondary to chylous pleural effusion to the University of Georgia Veterinary Teaching Hospital. Physical examination, complete blood count, serum chemistries, urinalysis, thoracic radiographs, abdominal radiographs, and thoracic fluid cytology and culture failed to identify an etiology for the chylous effusion. The patient tested negative for feline leukemia virus, feline immunodeficiency virus and heartworm disease. Respiration phasic influences on early diastolic trans-mitral, trans-tricuspid and pulmonary vein blood flow velocities during Doppler echocardiography were consistent with constrictive pericarditis. The cat underwent subtotal pericardectomy. The patient recovered without complication and is overtly healthy without radiographic or echocardiographic abnormalities 6-months post-surgery. Constrictive pericarditis should be considered in cats with idiopathic pleural effusion, with or without ascites, in which standard echocardiographic assessment is not suggestive of structural heart disease. If constrictive pericarditis is present, the Doppler characteristics outlined here may allow for this diagnosis to be made. Pericardectomy may be highly rewarding, although the specific etiology of the constrictive pericarditis may remain unknown.

Influence of combined angiotensin-converting enzyme inhibitors and spironolactone on serum K+, Mg 2+, and Na+ concentrations in small dogs with degenerative mitral valve disease.

OBJECTIVE: To determine if the administration of an angiotensin-converting enzyme inhibitor (ACEI) plus spironolactone caused hyperkalemia, hypermagnesemia, or hyponatremia in elderly small dogs with degenerative mitral valve disease (MVD). BACKGROUND: ACEIs and spironolactone can increase serum potassium and magnesium concentrations and lower serum sodium concentrations. It has been recommended to either not combine these drugs or to do so with caution. ANIMALS, MATERIAL AND METHODS: Fifty client-owned dogs with MVD, left atrial dilation, and without congestive heart failure or azotemia were evaluated retrospectively. Baseline data sets, followed by 1-9 (mean=2.66) data sets, comprised of serum urea nitrogen (SUN), creatinine, sodium, potassium, and magnesium concentrations, were tabulated. Each dog received an ACEI plus spironolactone for a mean of 23.8+/-26.6 weeks (range: 2-150) and a median of 15 weeks. No cardiac drugs other than an ACEI and spironolactone were administered during the study period. RESULTS: There were no significant differences between baseline and follow-up serum sodium or potassium concentrations. Serum magnesium concentrations increased significantly (p=0.02) with time >20 weeks compared to baseline. CONCLUSIONS: The combination of an ACEI and spironolactone results in no significant difference between baseline and follow-up serum sodium or potassium concentrations. Although serum magnesium concentrations may increase significantly with time >20 weeks compared to baseline concentrations, hypermagnesemia appears to be rare, mild, and unlikely to be of clinical importance. The combination of an ACEI and spironolactone is safe in elderly small dogs with MVD with normal SUN and creatinine concentrations.