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.     

Cardiac conotruncal malformations in a family of beagle dogs

O bjectives : To study forms of congenital heart disease present in a family of beagle dogs with a strong prevalence of ventricular septal defect and to document the pathological findings associated with the ventricular septal defects and investigate the mode of transmission.
M ethods : The animals were investigated by physical examination, radiography, electrocardiography and ultrasonography to diagnose the presence of congenital heart disease. Some animals were diagnosed at post-mortem examination and the dead animals underwent post-mortem examination to verify the presence of ventricular septal defect. An analysis of pedigree was undertaken and two of the affected animals were mated to investigate the mode of transmission.
R esults : Among the 28 dogs evaluated clinically or by post-mortem examination, 14 cases of ventricular septal defect were identified. The post-mortem examination showed some abnormalities of the ventricular outflow region associated with malformation of conotruncal septum development. When two affected dogs were bred, congenital heart disease was present in all of the offspring.
C linical S ignificance : The congenital heart disease identified in this beagle family can be classified as conotruncal malformation, and an autosomal recessive mode of inheritance was suggested by pedigree analysis.     

Congenital pericardial diaphragmitic hernia and multiple cardiac defects in a litter of collies

Four Collie littermates had multiple cardiac and diaphragmatic anomalies. Ventricular septal defect was found in 3, pulmonic stenosis in 2, atrial septal defect in 1, mitral regurgitaion in 1, and pericardial diaphragmatic hernia in 3. Five additional littermates died within 72 hours of birth but were not necropsied. On the basis of available evidence, it was believed that the defects were congenital but not hereditary.     

Ventricular Septal Defect Repair

Twelve dogs and one cat were operated to close a ventricular septal defect. The method of patient selection, associated lesions, techniques used to correct the defect and significance to the total population of small animals with congenital lesions is discussed. Ten of 13 animals survived surgery. When indicated, this procedure can be safely performed to correct ventricular septal defect.     

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.     

Congenital cardiac defects in calves

In a 14-year study of calves with cardiac defects, 36 had 78 congenital cardiac defects: ectopia cordia cervicalis (n = 10 defects), common aortic trunk (n = 3 defects), dextraposed aorta (n = 8 defects), duplicated major trunks (n = 1 defect), hypoplastic aorta (n = 2 defects), interventricular septal defect (n = 11), interatrial septal defect (n = 2), left ventricular hypoplasia (n = 10), patent ductus arteriosus (n = 5), patent foramen ovale (n = 5), right ventricular hypoplasia (n = 10), cor triloculare biatriatum (n = 1), endocardial fibroelastosis with calcification (n = 3), and valvular hematomas (n = 7). All septal defects were high in location and ranged from 5 to 35 mm in diameter. One calf with a septal defect also had bilateral microphthalmia.     

Percutaneous occlusion of a muscular ventricular septal defect with an Amplatzer® Muscular VSD occluder

Ventricular septal defects are a relatively common congenital cardiac disease that, when severe, can be associated with substantial morbidity and mortality. Several minimally invasive methods of repair have been described in the human literature. This report describes the first case of percutaneous closure of a naturally occurring muscular septal defect using an Amplatzer^® occluder in a dog affected by concurrent pulmonic stenosis. Based on this experience catheter-based occlusion of muscular ventricular septal defects is a feasible option in dogs. Further studies are necessary to identify the attributes and limitations of the technique.     

Congenital cardiac diseases in dogs: a retrospective analysis

In a time period of 6 years, 158 congenital cardiac defects were diagnosed in 146 dogs at the Clinic for Small Animal Medicine University of Zurich. In respect to all dogs with cardiac disease, these were 23.5% of the cases. Most common defects were subaortic stenosis (SAS, 31.5%), pulmonic stenosis (PS, 23.3%), ventricular septal defect (VSD, 14.4%), patent ductus arteriosus (PDA, 13.7%) and tricuspid dysplasia (TD, 7.5%). Complex defects were found in 8.2% of the dogs. Although single dogs per breed were affected by various defects, some breed-related tendencies could be observed. We found PS more numerously in boxers and Jack Russell Terriers whereas SAS, VSD and TD were also found in breeds reported to be predisposed. Congenital cardiac defects are an important clinical entity, and knowledge of prevalence is helpful when considering the differential diagnosis and for making a tentative diagnosis in an individual case.     

Pulmonic stenosis and right-to-left atrial shunt in three dogs

Using cardiac catheterization, pulmonic stenosis and right-to-left atrial shunt were diagnosed in 3 young dogs that were evaluated because of weakness, cyanosis, and polycythemia. Injection of contrast material into the caudal vena cava or crossing the atrial septal defect with the catheter tip from the right atrium into the left atrium confirmed the diagnosis. Tetralogy of Fallot, with right-to-left shunt through a ventricular septal defect, is a more common congenital malformation associated with the aforementioned clinical signs. Differentiation between the 2 defects is important, because surgical decompression of the right ventricle will lead to reduction of right atrial pressure and diminishment of the shunt.     

Atrial septal defect in five dogs

The clinical, electrocardiographic, radiographic, and two-dimensional, M-mode and Doppler echocardiographic findings of five cases of canine ostium secundum type atrial septal defect (ASD) are described. The atrial septal anomaly was associated with other congenital cardiac abnormalities in two dogs: ventricular septal defect in one case and tricuspid dysplasia in the other. ASD was found in addition to dilated cardiomyopathy and suspected atrial thrombosis in one geriatric dog, but was the only cardiac abnormality detected in the remaining two dogs. Colour Doppler imaging facilitated the diagnosis of ASD in all subjects. The long-term prognosis for dogs with isolated and small-sized ASD is usually good, but can be compromised by the presence of concurrent congenital or acquired cardiac diseases.     

Retrospective study of congenital heart defects in 151 dogs

The case records of 151 dogs diagnosed with congenital heart disease were revlewed retrospectlvely. The most common defect Was aortic stenosls, accounting for 35 per cent of all cases, followed by pulmonic stenosls (20 per cent), ventricular septal defect (12 per cent), patent ductus arterlosus (11 per cent), mltral valve dysplasla (8 per cent), tricuspld valve dysplasla (7 per cent), endocardlal fibroelastosls (1.9 per cent) and tetralogy of Fallot (04 per cent). Fifty-one breeds were represented, with golden retrievers, German shepherd dogs and boxers predominating. No overall sex predilection was obvious. Seventy-five per cent of the dogs were asymptomatic presentation. The defects most often associated with presenting symptoms, such as dyspnoea, syncope, ascltes, fallure to grow and depression, were mltral valve dysplasla, atrial septal defect, tricuspld valve dysplasla and endocardial flbroelastosls. The latter presented with the most severe signs of heart fallure. In some cases of aortic stenosls and pulmonlc stenosls, where the defect could not be accurately visuallsed with two-dimensional echocardlography, Doppler echocardlographic examination was needed for definltive dlagnosls.     

Comparison of techniques for transdiaphragmatic thoracic drainage after diaphragmatic defect closure in dogs: a cadaveric study

Four thoracic evacuation techniques for pneumothorax elimination after diaphragmatic defect closure were compared in 40 canine cadavers. After creating a defect in the left side of the diaphragm, thoracic drainage was performed by thoracostomy tube insertion through the defect and a small (DD-SP) or large (DD-LP) puncture created in the caudal mediastinum, or through both the diaphragmatic defect and intact contralateral diaphragm with a small (DI-SP) or large (DI-LP) puncture in made in the caudal mediastinum. Differences in intrapleural pressure (IPP) between the right and left hemithoraxes after air evacuation along with differences in IPP before making a defect and after air evacuation in each hemithorax were calculated. A difference (p ≤ 0.0011) in IPP between the left and right hemithoraxes after air evacuation as well as before making a defect and after air evacuation in the right hemithorax was detected for the DD-SP group. No significant differences (p ≥ 0.0835) were observed for the DI-LP, DD-LP, or DI-SP groups. Creation of a large mediastinal puncture or thoracic evacuation through both a diaphragmatic defect and intact contralateral diaphragm can facilitate proper pneumothorax elimination bilaterally after diaphragmatic defect closure in dogs with a small puncture in the caudal mediastinum.     

Aortic endocarditis associated with a perforated septal membranous aneurysm in a boxer dog

Perimembranous ventricular septal defect is a common congenital heart disease in the dog. It can partially or completely close with age by development of a membranous ventricular septal aneurysm. Aortic endocarditis is a reported complication of ventricular septal defect and membranous ventricular septal aneurysm in human beings. This report describes a case of aortic endocarditis associated with a membranous ventricular septal aneurysm perforated by a small ventricular septal defect in a boxer dog.     

Assessment of survey radiography as a method for diagnosis of congenital cardiac disease in dogs.

In order to assess the diagnostic accuracy of survey radiography for canine congenital cardiac anomalies, thoracic radiographs of 57 dogs with congenital cardiac anomalies, 31 normal dogs and 27 dogs with acquired cardiac disease were mixed, and reviewed by two independent observers, who were blinded to any patient information. The congenital anomalies were aortic stenosis (n=25), pulmonic stenosis (n=10), patent ductus arteriosus (n=9), ventricular septal defect (n=8), tricuspid dysplasia (n=3) and mitral dysplasia (n=2). Both observers were moderately accurate at identifying dogs with cardiac disease. Their ability to distinguish dogs with congenital versus acquired cardiac disease was poorer and this assessment was probably influenced by the recognition of patients that were skeletally immature, which biased observers towards a diagnosis of congenital cardiac anomaly. The diagnosis rate for specific congenital anomalies was also poor (the differential list included a correct diagnosis in only 40 and 37 per cent of cases). Radiographic signs of specific cardiac chamber enlargement or pulmonary vascular abnormalities were recognised by both observers in only 20 per cent of instances in which they might be expected. They were, however, recognised more frequently in dogs with anomalies that imposed a volume load on the heart than in dogs with anomalies that induced a pressure load on the organ. It is concluded that survey radiography is an inaccurate method for diagnosis of canine congenital cardiac anomalies because of the difficulty of recognising radiographic signs, which are not present in many cases.     

Teratogenic effect of acetohydroxamic acid in clinically normal beagles

Acetohydroxamic acid (AHA), a potent urease inhibitor used for treatment of infection-induced struvite urolithiasis, was teratogenic after administration of 25 mg of AHA/kg of body weight/day orally to 5 clinically normal Beagles from the onset of proestrus until parturition. Thirty pups exposed to AHA in utero developed anomalies of the skeletal system, heart, and ventral midline. Cardiac anomalies included atrial septal defects (20%), ventricular septal defects (3%), and atrial and ventricular septal defects (3%). Skeletal anomalies included coccygeal hemivertebrae and fused coccygeal vertebrae (50%), supernumerary vertebrae (67%), supernumerary ribs (50%), duplicated sternebrae (3%), and lumbar hemivertebrae (3%). Defects of the ventral midline of the abdominal wall occurred in 20% of AHA-exposed pups. Other abnormalities included retarded growth, high neonatal mortality, and a decreased number of circulating RBC, compared with those in 30 control pups born to 5 Beagles given a placebo. Adverse effects of AHA in pregnant Beagles were limited to morphologic alterations (Howell-Jolly bodies, spherocytes, and target cells) in a small number of circulating RBC. Slight neutrophilic leukocytosis and monocytosis occurred between 0 and 30 days of pregnancy in dogs given AHA, compared with those in controls. Seemingly, AHA did not influence fertility, conception rate, or length of gestation.     

Open surgical repair of tetralogy of Fallot in dogs.

Tetralogy of Fallot is a congenital heart defect that causes cyanosis, severe progressive weakness and activity intolerance, polycythemia, and shortened life span in dogs. Open surgical repair of tetralogy of Fallot consisting of closure of the ventricular septal defect and reconstruction of the right ventricular outflow tract via a right ventriculotomy during cardiopulmonary bypass is feasible in severely affected dogs. Successful surgical repair can completely resolve clinical signs associated with the defect.     

Interruption of aortic arch in two foals

Two foals with a history of normalcy at birth developed a lack of exercise tolerance and weakness in the first few days of life. Weakness, inability to rise, and reluctance to suckle were common complaints. Physical examination of both foals revealed a cardiovascular abnormality, with a loud systolic murmur audible over both thoracic walls. Additional diagnostic techniques were blood gas analysis, radiography, cardiovascular catheterization, and necropsy. Necropsy findings were ventricular septal defect, atrial septal defect, patent ductus arteriosus, and congenital absence of the aortic arch. Additionally, 1 foal had anomalous drainage of the cranial vena cava into the left atrium.     

Trifoliate left atrioventricular valve with and without intact septal structures in four dogs: echocardiographic findings and surgical repair

Trifoliate left atrioventricular (AV) valve with common atrioventricular junction is considered part of the spectrum of atrioventricular septal defect. This valve morphology is typically associated with defects in the AV septum resulting in communication at the atrial or ventricular level, but has also been described as an isolated defect in the setting of a common AV junction without AV septal defect. Trifoliate left AV valve exhibits a line of apposition between the bridging leaflets that is directed toward the inlet interventricular septum, distinguishing it from isolated mitral valve cleft in which the orientation of the bridging leaflets are toward the left ventricular outflow tract. The echocardiographic findings of four dogs with trifoliate left AV valve are described; two with intact septal structures and two with large ostium primum defects. Three dogs underwent open surgical repair using different approaches depending on the presence or absence of a septal defect. One of these underwent concurrent surgical repair for right AV valve dysplasia. One dog with intact septal structures underwent interventional closure of a concurrent patent ductus arteriosus. Current terminology associated with trileaflet left AV valve malformations is reviewed.     

Hereditary congenital heart defects in dogs

Congenital heart defects is probably the most common class of malformations found in dogs, occurring with a frequency approaching 1 per cent in animals presented to veterinary clinics. The frequency is significantly higher among purebred dogs than in dogs of mixed breeding and specific anatomic malformations occur with highest frequency in certain breeds. Genetic studies of patent ductus arteriosus, pulmonic stenosis, subaortic stenosis, ventricular septal defect, tetralogy of Fallot and persistent aortic arch have confirmed that these are specific heritable defects, the genes for which are concentrated in a number of different breeds. Each of these defects is inherited in a complex manner consistent with a polygenic basis. This paper will describe evidence supporting the view that the common forms of congenital heart disease in the dog are polygenic threshold traits. The general criteria for recognition of polygenic traits and methods for their control will be discussed.