Ventricular septal defect with aortic valve insufficiency in a New Zealand White rabbit

A heart murmur was detected in a 10 mo old, female New Zealand White rabbit. Auscultation revealed cardiac murmurs both at the left and right hemithorax. Phonocardiography confirmed the systolic-diastolic nature of the left-sided and the systolic character of the right-sided murmur. Electrocardiography showed normal sinus rhythm; tall R waves and large T waves in lead II; and deep S waves in leads II, III, and aVF. Thoracic radiography demonstrated generalized cardiomegaly with prominent pulmonary vasculature. Echocardiography revealed a perimembraneous ventricular septal defect with aortic insufficiency. Signs of biventricular volume overload, relative pulmonic stenosis, and pulmonary valve insufficiency were also seen as consequences of the defect. Necropsy demonstrated a ventricular septal defect just below the aortic valve, a dilated pulmonary trunk, dilated and hypertrophied ventricles, dilated atria, and rightward displacement of the aortic root. Cardiac histopathology showed ventricular cardiomyocyte degeneration (swelling and hypereosinophilia of the cytoplasm with a loss of cross striation, and nuclear hyperchromasia), cartilaginous metaplasia of the aorta, and subendocardial fibrosis of the right ventricular flow tract.     

Echocardiographic diagnosis of an anomaly of the tricuspid valve in a male pygmy goat.

A 3-year-old male pygmy goat was evaluated because of a grade III/V plateau pansystolic murmur that was auscultated over the tricuspid valve area and a grade II/V plateau pansystolic murmur that was auscultated over the left heart base. Echocardiography revealed a large right atrium and ventricle, an atrial septal defect, and a dysplastic tricuspid valve displaced apically into the right ventricle. Contrast echocardiography and color-flow Doppler echocardiography revealed flow from right to left through the atrial septal defect and severe tricuspid regurgitation. A diagnosis of tricuspid valve dysplasia and severe tricuspid regurgitation was made. This anomaly (Ebstein's anomaly) of the tricuspid valve should be considered in goats that have systolic, with or without diastolic, murmurs over the tricuspic valve. Two-dimensional echocardiography can confirm the diagnosis of the anomaly. The associated tricuspid regurgitation and interatrial right-to-left shunt flow can be detected and semiquantitated by use of contrast, continuous wave, and color-flow Doppler echocardiography.     

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.     

Ventricular septal defect in a blue duiker (Cephalophus monticola).

A 9-mo-old female blue duiker (Cephalophus monticola) weighing 3.9 kg was diagnosed with a cardiac murmur during quarantine examination. Evaluation of the heart by auscultation, electrocardiography, two-dimensional echocardiography, and Doppler color-flow echocardiography revealed a restrictive outlet ventricular septal defect with left atrial and left ventricular dilation. Trivial mitral, tricuspid, and aortic regurgitation was also noted. Though the duiker was clinically asymptomatic at the time of cardiac evaluation, it was found dead 1 wk later. The cause of death was not determined.     

DILATED CORONARY SINUS IN A DOG WITH PERSISTENT LEFT CRANIAL VENA CAVA

This paper describes the electrocardiographic, echocardiographic (two-dimensional, M-mode, contrast and Doppler) and non-selective angiocardiographic features in a 3 year old female Beagle with dilated coronary sinus due to persistent left cranial vena cava. Negative P waves in leads III and aVR and a positive P wave in lead aVL were seen. Echocardiographically, a hipoechoic circular structure was seen between the left atrium and the pericardium in the area where the coronary sinus is located. A velocity pattern with two peaks was obtained, one systolic with velocity = 0.44 ± 0.05 m/sec and the other diastolic with velocity = 0.27 ± 0.01 m/sec. By M-mode echocardiography, at level of the aorta and the left atrium, a linear structure was identified between the left atrium and the pericardium; this structure was characterized by phasic movements of the anterior wall during the cardiac cycle. Following a left cephalic vein injection of saline, bubbles were seen within the coronary sinus; when saline was injected into the right cephalic vein, bubbles were also seen within the coronary sinus and right atrium and ventricle. Non-selective angiocardiography confirmed a dilated coronary sinus with persistent left cranial vena cava. The right cranial vena cava was absent. The dog was clinically normal and the unusual vessel was an incidental finding.     

Left coronary aneurysmal dilation and subaortic stenosis in a dog

A 6-month-old German shepherd dog was referred for evaluation of a cardiac murmur.Upon physical examination, the auscultated heart rate was 120 beats/min, and a grade IV/VI systolic heart murmur with a point of maximal intensity over the left heart base radiating up the neck was heard. The standard echocardiographic examination showed subaortic stenosis and an anechoic tubular structure extending from the sinus of Valsalva to the left ventricular posterior wall. Aneurysmal left coronary artery (CA) was confirmed by angiography. The dog was euthanized and post-mortem examination showed severe dilatation of the proximal left CA and confirmed the subaortic stenosis. Histopathology did not demonstrate abnormalities in the walls of the CA, aorta or pulmonary artery.The exact cause of the CA aneurysmal dilation remains unknown. Subaortic stenosis, elevated coronary vascular resistance or a congenital anomaly may have contributed to the dilation.To our knowledge, coronary aneurysmal dilation has never been described in dogs. Standard echocardiography provides reliable information on coronary anatomy.     

Normal and paradoxical ventricular septal motion in the dog

Normal and paradoxical ventricular septal motions were studied in dogs, using M-mode and 2-dimensional echocardiography. Normal ventricular septal motion was evaluated, using 35 clinically healthy dogs (group I), and was compared with characteristics of septal motion measured in 12 dogs with right ventricular overload (group II) and 14 dogs with left-sided heart disease (group III). Normal ventricular septal motion consisted of a series of active and passive anterior (right cranial) and posterior (left caudal) movements that were subjectively evaluated and quantitated during segments of the cardiac cycle. Maximum excursion of the ventricular septum occurred during systole, was directed toward the left ventricle, and was related to body size. Determination of a normalized radius of septal curvature from analysis of 2-dimensional echocardiogram indicated that the septal arc formed part of a generally circular left ventricle in group I dogs. In contrast to these findings, group II dogs with right ventricular pressure and volume overloads exhibited reduced systolic septal excursion, diminished or flat septal motion, and paradoxical systolic septal motion. Normalized radius of septal curvature was significantly greater in group II dogs than in group I or group III dogs. Septal motion and radius of septal curvature in dogs comprising group III were not significantly different from normal during most phases of the cardiac cycle. Results of this study support the concept that septal motion is a reflection of overall left ventricular shape and that abnormalities in ventricular septal motion, namely flat or paradoxical septal motion, should cause the clinician to suspect right ventricular volume or pressure overload.     

Eisenmenger's complex in a Holstein-Friesian cow

A 4.5-year-old, Holstein-Friesian cow presented with a 1-month history of severe exercise intolerance. Rectal examination and transrectal ultrasonography revealed a large mass in the left retroperitoneum. The heart rate was 70 to 80/min. Premature ventricular complexes and ventricular bigeminy were present on an electrocardiogram. Erythrocytosis was present and blood gas analysis revealed marked hypoxaemia. An echocardiogram demonstrated a large ventricular septal defect, a partially dextroposed aorta, and concentric hypertrophy of the right ventricular free wall. Colour flow Doppler echocardiography and a contrast echocardiographic study demonstrated a right-to-left shunt through the ventricular septal defect. Eisenmenger's complex was diagnosed. The patient was euthanased. Necropsy confirmed the gross cardiac lesions identified by echocardiography and an abscess in the apex of the left ventricle. Severe pulmonary arterial lesions were present, consistent with a marked increased in pulmonary vascular resistance. Actinomyces pyogenes was cultured from abscesses of the retroperitoneum and the ventricular apex.     

Right coronary artery to left ventricle coronary cameral fistula in a cat

A six-month-old female intact domestic shorthair cat was presented for evaluation of a loud heart murmur. Transthoracic echocardiography revealed dilation of the left ventricle secondary to an abnormal vessel shunting blood into the left ventricular outflow tract at a high velocity during diastole. Multidetector computed tomography angiography revealed a coronary cameral fistula that originated at the right coronary artery, encircled the heart, and then terminated into the left ventricular outflow tract. This case report documents the first known case of a coronary cameral fistula in a cat. Multimodal imaging was an essential aspect to diagnosing the congenital lesion in this case.     

Tricuspid atresia in a foal

An Arabian crossbred foal was examined because of a suspected congenital cardiac anomaly. There was a grade V/V crescendo-decresendo holosystolic murmur and thrill in the left 4th intercostal space. The foal was slightly cyanotic and polycythemic. Electrocardiography suggested left ventricular hypertrophy. Angiography and cardiac and vascular pressure recordings led to a diagnosis of pulmonic stenosis. The foal died after cardiac bypass and corrective surgery. Postmortem examination revealed an enlarged right atrium, atresia of the tricuspid orifice, a large, fenestrated patent foramen ovale, eccentric left ventricular hypertrophy, and a large interventricular septal defect. The right ventricle had a small lumen and a relatively thick wall. There was valvular and supravalvular pulmonic stenosis, with poststenotic dilatation of the pulmonary artery. A single coronary artery originated from the anterior sinus of the aorta.     

Complex cardiac congenital defects in an adult dog: An ultrasonographic and magnetic resonance imaging study

This article describes a complex and not previously reported combination of congenital cardiac defects. Echocardiography showed dilation of right and left chambers, accompanied with patent ductus arteriosus, persistence of the left cranial vena cava, atrial septal defect (ASD), subaortic stenosis, and tricuspid dysplasia. The interatrial wall was examined and the diameter of the ASD was measured by magnetic resonance imaging (MRI).     

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.     

Reversible pulmonary hypertension presenting simultaneously with an atrial septal defect and angiostrongylosis in a dog

A one-year-old female neutered beagle was presented with marked abdominal effusion. Echocardiography showed marked dilatation of the right cardiac chambers, an atrial septal defect and severe tricuspid insufficiency. Systolic pulmonary arterial pressure (sPAP), evaluated by continuous wave Doppler echocardiography, was very high (80 mmHg), with a right to left interatrial shunt. The radiographic images were compatible with widespread pneumonitis. Numerous larvae of Angiostrongylus vasorum were visible on direct faecal examination. The animal was given fenbendazole for 15 days, combined with diuretics, an antibiotic and a vasodilator. Two weeks later, the dog showed a marked improvement. The treatment, except the anthelmintic, was continued for seven weeks and then stopped. At that stage, Doppler echocardiography revealed that the sPAP had returned to normal (20 mmHg) and the interatrial shunt had reversed (left to right). Eighteen months later, clinical and Doppler echocardiographic examinations were normal.     

Interventional Closure of a Patent Ductus Arteriosus Using an Amplatz Canine Duct Occluder in an Alpaca Cria

A 6‐month old female alpaca cria presented to The Ohio State University for evaluation of a cardiac murmur. Echocardiography revealed a left‐to‐right shunting patent ductus arteriosus, a restrictive left‐to‐right shunting perimembranous ventricular septal defect, and secondary moderate left atrial and ventricular dilation. Aortic root angiography demonstrated a type IIA patent ductus arteriosus (PDA). Interventional closure of the PDA was successfully performed, without complication, using an Amplatz canine duct occluder. This case report describes the materials and methods used for interventional closure of a PDA in an alpaca cria.     

Heterogeneity of Hypertrophy in Feline Hypertrophic Heart Disease

Eighty-six cats with non-dilated left ventricular myocardial hypertrophy were studied retrospectively. Cats were categorized by two-dimensional echocardiography as having symmetric ventricular hypertrophy (Type I), asymmetric with predominant septal thickening hypertrophy (Type II), and asymmetric hypertrophy with predominant free-wall thickening (Type III). The distribution of hypertrophy was judged subjectively and objectively. Subjective and objective results were similar (P= 0.03) although overlap existed between groups. Morphologic patterns (Types I, II, and III) were compared with breed, age, sex, heart rate, percent fractional shortening, left atrial size, serum creatinine concentration, and the presence (yes/no) of pleural effusion, pulmonary edema, pericardial effusion, heart murmur, dyspnea, thromboembolism, hyperthyroidism, and being alive at the time of study. Interventricular septal thickness, left ventricular free wall thickness, percent fractional shortening, and left atrial size additionally were compared to 3-month survival. Cats with Type HI hypertrophy were more likely to experience thromboembolism than cats with Type II hypertrophy (P= 0.05) and cats with Type I hypertrophy were more likely to have heart murmurs than cats with Type III (P= 0.02). No other significant associations were found in comparison to pattern of hypertrophy. Both left atrial size and percent fractional shortening significantly correlated with 3-month survival (P < 0.001 for each). The degree of interventricular septal wall thickness was associated with 3-month survival (P= 0.02) when known hyperthyroid cats were excluded from the study group, while left ventricular free wall thickness consistently was not associated with survival. This study demonstrates the heterogeneity of hypertrophy in cats with hyper-trophic heart disease and provides predictors of survival (left atrial size, percent fractional shortening, and interventricular septal wall thickness when compared with euthanasia/spontaneous death data).     

Persistent truncus arteriosus in a cat

A 5-month-old male domestic cat presented with a history of rapid, heavy breathing and cyanosis after exercise. Physical examination showed an abnormal respiratory pattern with an increased rate and stress-induced cyanosis. Auscultation revealed tachycardia and a grade 5/6 systolic murmur best heard over the left base. Radiographs showed evidence of right atrial and ventricular enlargement with distended pulmonary vessels and an enlarged ascending aorta. An echocardiographic examination revealed a dilated right atrium, eccentric right ventricular hypertrophy and an overriding aorta associated with a large ventricular septal defect (VSD). The pulmonary trunk could not be identified by echocardiography. Doppler and saline contrast studies showed large right-to-left shunting through the VSD. These findings were compatible with persistent truncus arteriosus, which was confirmed at necropsy.     

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.     

Tetralogy of Fallot and atrial septal defect in a white Bengal Tiger cub (Panthera tigris tigris)

A 3-week-old female white Bengal Tiger cub (Panthera tigris tigris) presented with acute onset tachypnoea, cyanosis and hypothermia. The cub was severely hypoxaemic with a mixed acid–base disturbance. Echocardiography revealed severe pulmonic stenosis, right ventricular hypertrophy, high membranous ventricular septal defect and an overriding aorta. Additionally, an atrial septal defect was found on necropsy, resulting in the final diagnosis of Tetralogy of Fallot with an atrial septal defect (a subclass of Pentalogy of Fallot). This report is the first to encompass arterial blood gas analysis, thoracic radiographs, echocardiography and necropsy findings in a white Bengal Tiger cub diagnosed with Tetralogy of Fallot with an atrial septal defect.     

Arrhythmogenic right ventricular dysplasia/cardiomyopathy in a Siberian husky

A seven-month-old male Siberian husky was presented with a recent history of anorexia, hindlimb weakness and syncope. Physical examination revealed severe tachycardia, tachypnoea and dyspnoea. Mucous membranes were pale and femoral pulses were weak. An electrocardiogram showed sustained ventricular tachycardia with a left bundle branch block configuration. Thoracic radiographs revealed slight right ventricular enlargement and two-dimensional echocardiography revealed mild right ventricular dilation at the cardiac apex and some hyperechogenic areas on the right side of the interventricular septum. Administration of intravenous lignocaine converted the ventricular tachycardia to sinus rhythm. The maintenance antiarrhythmic therapy consisted of oral procainamide and propranolol. Three weeks later the dog died suddenly. On postmortem examination, the right ventricular free wall was very thin at the apex, infundibulum and caudal aspect of the right ventricular parietal wall, similar to the 'triangle of dysplasia' of human patients. Histopathological examination revealed replacement of several areas of right ventricular free wall myocardium with connective tissue and fat. The right atrium and left ventricle were less severely affected by the same lesions. The clinical and pathological findings are similar to those reported in young people with arrhythmogenic right ventricular dysplasia/cardiomyopathy.