Echocardiographic diagnosis of congenital membranous ventricular septal aneurysm in the dog and cat

Membranous ventricular septal aneurysm was diagnosed by echocardiography in 17 dogs and three cats. The aneurysm appeared as a thin membrane protruding into the right ventricle from the margins of a congenital ventricular septal defect (VSD). The aneurysm was intact in nine dogs and two cats and perforated by a small VSD in eight dogs and one cat. Other congenital heart defects were present in seven dogs. In all animals, the aneurysm was an incidental finding observed during echocardiographic examination, and it did not appear to directly cause any cardiac dysfunction.     

Spontaneous resolution of an isolated ventricular septal defect in a dog

A 5-month-old Maltese was examined because of a holosystolic heart murmur. Results of echocardiography were suggestive of a small isolated interventricular septal defect. Color flow and pulsed-wave spectral Doppler echocardiography confirmed that there was left-to-right blood flow through the defect during systole and diastole. Because of the small size of the defect, the large systolic pressure differential between the ventricles (72.6 mm Hg), and the lack of clinical signs, the small amount of left-to-right shunting was considered clinically unimportant, and no medication or treatment was recommended. Seven months later, the dog was re-examined, and trans-septal blood flow was no longer seen. Isolated interventricular septal defects are a common congenital heart disorder in some breeds of dogs. Such defects may be subclinical in some dogs. In others, they cause a wide spectrum of clinical problems. Findings in this dog suggest that interventricular septal defects may close spontaneously in some dogs.     

Surgical correction of a partial atrioventricular septal defect with a ventricular septal defect in a dog

Echocardiography of a dog with a cardiac murmur revealed an ostium primum septal defect, a ventricular septal defect, and mitral valve malformation with regurgitation. The mitral valve and tricuspid valve were separated and displaced at the same level as the ventricular septum. The mitral valve had a cleft in the septal cusp. Cardiac catheterization and angiocardiography showed a left-to-right shunt and a "goose-neck sign," which indicated an elongated left ventricular outflow tract. The diagnosis of a partial atrioventricular septal defect with ventricular septal defect was made. Surgical correction was successfully performed under extracorpo-real circulation using a cardiopulmonary bypass system.     

Pulmonary atresia and ventricular septal defect with aortopulmonary collaterals in an adult dog

Pulmonary atresia and ventricular septal defect (PA-VSD) was diagnosed in a 2-year-old castrated male Terrier mix. Transthoracic echocardiography identified a large ventricular septal defect, overriding aorta and severe right ventricular hypertrophy. A main pulmonary artery could not be identified, consistent with pulmonary atresia or persistent truncus arteriosus. Transesophageal echocardiography and angiography confirmed PA-VSD with aortopulmonary collateral circulation arising from the descending thoracic aorta. This case report describes the antemortem diagnosis of the rare congenital defect PA-VSD in an adult dog.     

Percutaneous transcatheter coil embolization of a ventricular septal defect in a dog

A 4-month-old male French Bulldog weighing 5.0 kg (11 lb) was referred for a heart murmur. A grade 3/6 systolic murmur was detected at the left heart base and a grade 4/6 systolic murmur was detected at the right heart base. By use of color-flow Doppler ultrasonography and cardiac catheterization, a diagnosis of supracristal ventricular septal defect (VSD) with accompanying aortic regurgitation was made. Percutaneous transcatheter coil embolization was used to close the VSD. Because residual shunt was detected via echocardiography after coil implantation, the residual shunt was followed periodically via echocardiography to detect spontaneous closure of the VSD. Volume overload in the left ventricle was detected in the dog 131 days after admission. Additional coils were placed 137 days after admission. Hemolysis resulting in hemoglobinuria was detected, but this complication was mild. In the dog of this report, results of coil occlusion for correction of VSD were promising. Thus, coil occlusion should be considered as an alternative treatment for VSD in dogs.     

Surgical correction of ventricular septal defect with aortic regurgitation in a dog

An 8-month-old entire Miniature Dachshund, weighing 4.2 kg, was presented for examination following delvelopment of a cough. Ventricular septal defect had been diagnosed tentatively in its infancy on the basis of a cardiac murmur detected by auscultation and echocardiography. Echocardiography using a B mode right parasternal long-axis view showed a defect at the atrioventricular junction and a thickened cusp of the aortic valve prolapsing into the defect. Colour-flow Doppler showed shunt blood flow across the defect at the level of the atrioventricular junction, from left to right. The sinus of Valsalva was dilated, with turbulent blood flow. Aortic regurgitation was also observed. Cardiac catheterisation studies confirmed the diagnosis of a supracristal ventricular septal defect with aortic regurgitation. Despite medication with digoxin, enalapril and aminophylin, started from the first admission, left ventricular internal dimensions gradually increased, and fractional shortening of the left ventricle gradually decreased. Surgery, with the aid of extracorporeal circulation, to close the ventricular septal defect, was performed 1 year after the initial examination. The aortic valve was left untreated. Postoperatively, the systolic murmur disappeared. Shunt flow from the left to the right ventricle was no longer observed on echocardiography, however there was still a small amount of aortic regurgitation during diastole visualised with colour-flow Doppler echocardiography. The prolapse of the cusp of the aortic valve on B-mode echocardiography was no longer observed and thickening of the cusp had not progressed. Left ventricular function measurement using M mode echocardiography showed a reduced left ventricular volume overload with reduced left ventricular internal dimensions and increased fractional shortening. The cough was relieved and no follow-up medication was scheduled. Early surgical closure of the ventricular septal defect improved the patient's condition and controlled prolapse and thickening of the aortic valve.     

Aorticopulmonary septal defect in a dog.

A 2-year-old Brittany Spaniel ahd clinical signs of pulmonary diseases and pulmonary hypertension, with cardiac murmur and congestive heart failure. Aorticopulmonary septal defect was detected by means of cardiac catheterization. Attempted surgical correciton was unsuccessful.     

Aorticopulmonary septal defect in a German shepherd dog

A 2-year-old, female German shepherd dog was referred with a 2-month history of dyspnea, ascites, and anorexia. On physical examination, an arrhythmia, tachypnea, and a continuous grade V/VI heart murmur were evidenced. Atrial fibrillation and tall R waves were noted on electrocardiography. Survey thoracic radiography revealed generalized cardiomegaly and enlarged pulmonary vessels. Echocardiography demonstrated severe dilatation of the left atrium and ventricle with reduced fractional shortening. Doppler echocardiography showed continuous and turbulent flow in the ascending aorta between the aorta and the pulmonary artery. Necropsy demonstrated an aorticopulmonary septal defect.     

Normal parameters in abdominal radiology of the dog and cat

The size, position and ease of demonstration of the major abdominal viscera have been recorded in a series of two hundred consecutive radiographic examinations of the dog and cat. Only the values for viscera either known to be normal following surgery or autopsy, or presumed to be normal on the basis of clinical findings, are presented. All values are expressed as a ratio of the length of the second lumbar vertebral body. The factors affecting organ visibility and the variations in normal organ size are discussed.     

Situs inversus totalis associated with subaortic stenosis, restrictive ventricular septal defect, and tricuspid dysplasia in an adult dog

A rare association between situs inversus totalis (SIT), restrictive ventricular septal defect, severe subaortic stenosis, and tricuspid dysplasia was observed in an adult mixed-breed dog. Primary ciliary dyskinesia and Kartagener's syndrome were excluded. After 15 mo the dog died suddenly. The association between SIT and congenital heart diseases is discussed.     

Left ventricular myxosarcoma in a dog

An entire male Neopolitan mastiff, aged two years and eight months, presented with a history of chronic diarrhoea and weight loss. The diarrhoea had been present for approximately 12 months and had progressively worsened, with weight loss developing over an eight-week period prior to presentation. No primary gastrointestinal or metabolic cause for the diarrhoea could be identified. Echocardiography revealed a large, multilocular, cyst-like structure within the pericardium compressing the heart and displacing it to the right. The mass was surgically excised from the left ventricular myocardium. Histopathological examination showed it to be a low-grade malignant myxosarcoma. The dog made a full recovery and was still clinically normal nine months postoperatively, with no evidence of tumour recurrence or metastases. However, 11 months postsurgery, the clinical signs of diarrhoea and weight loss returned. Tumour recurrence with local metastasis was diagnosed and the dog was euthanased 358 days after the original surgery.     

Arrhythmogenic right ventricular cardiomyopathy in a dog

An 8-month-old Labrador retriever bitch was evaluated for sudden-onset, progressive abdominal distension. Physical examination revealed an exaggerated inspiratory effort, severe ascites, bilateral jugular vein distension, and hypokinetic femoral arterial pulses. Thoracic auscultation detected tachycardia with muffled heart sounds, without audible cardiac murmurs. Thoracic radiographs identified severe right ventricular enlargement and pleural effusion. The electrocardiogram was consistent with incomplete right bundle branch block or right ventricular enlargement. Echocardiography demonstrated severe right ventricular and atrial dilation, secondary tricuspid regurgitation, and thinning and hypocontractility of the right ventricular myocardium. Left heart chamber sizes were slightly decreased, with normal left ventricular contractility. A diagnosis of arrhythmogenic right ventricular cardiomyopathy was reached, based on the characteristic clinical, electrocardiographic, radiographic and echocardiographic findings, and the exclusion of other causes of isolated right ventricular failure. Treatment effected good control of clinical signs, until acutely decompensated congestive right heart failure led to euthanasia after 4 months. Arrhythmogenic right ventricular cardiomyopathy is a well-described clinical entity in humans, and has previously been documented in 3 male dogs. The condition is characterised by progressive fibro-adipose replacement of right ventricular myocardium, while the left ventricle usually remains unaffected. It should be considered a differential diagnosis in any young dog presented with isolated right heart failure, syncope, or unexplained ventricular tachyarrhythmias. This article reports the 1st case of arrhythmogenic right ventricular cardiomyopathy in a female dog, and highlights its echocardiographic features.     

Ventricular septal defect repair in a small dog using cross-circulation

SUMMARY A haemodynamically significant ventricular septal defect was diagnosed in a 3-month-old male Cavalier King Charles Spaniel. A median sternotomy was performed and the 6.5 kg dog placed on cardiopulmonary bypass using pump-assisted cross-circulation. A 10 mm diameter peri-membranous ventricular septal defect was closed using a continuous suture of 4–0 polypropylene, via a 2.5 cm incision in the right ventricular outflow tract. The duration of cardiopulmonary bypass was 90 minutes. Complications in the immediate postoperative period were mild and easily managed.