Trans-pulmonary stent placement for pulmonary stenosis in a dog with a type R2A coronary artery anomaly.

A one-year-old male intact American bulldog was presented for evaluation of previously diagnosed pulmonary stenosis. Echocardiography identified ultra-severe stenosis with an instantaneous trans-pulmonary pressure gradient of 240 mmHg. Angiography confirmed the presence of an anomalous coronary artery with a prepulmonic course of the left coronary artery arising from a single right coronary ostium consistent with a type R2A coronary anomaly. A trans-pulmonary stent was successfully placed transvenously with diameter sizing based on coronary compression testing. No coronary compression was present on postimplantation angiography. A marked reduction in the pressure gradient was obtained on postoperative echocardiography (reduction to 68 mmHg), despite selecting a stent diameter less than the pulmonary annulus diameter. This is the first report of the use of coronary compression testing in transvenous trans-pulmonic stent implantation in a dog with a type R2A coronary artery anomaly. Selection of a stent diameter less than the pulmonary annulus diameter conveyed a clinically relevant reduction in the trans-pulmonic pressure gradient while avoiding coronary compression in this case.

Anomalous origin of the right coronary artery from the pulmonary artery in a Staffordshire bull terrier.

An asymptomatic 17-month-old, 18.5-kg, male Staffordshire bull terrier was referred due to a heart murmur. Examination revealed a grade 3/6 left apical systolic and right apical 3/6 heart murmur. Echocardiography showed volume overload of the left ventricle and mild systolic dysfunction with a left-right flow over the interventricular septal region. Cardiac gated computed tomography revealed anomalous origin of the right coronary artery from the pulmonary artery, an extensive network of collateral blood vessels connected the right and left coronary arteries, with bronchial and left intercostal arteries also connected to the network of collateral blood vessels, markedly enlarged right and left coronary arteries and left coronary sinus. With varied presentation, coronary anomalies are difficult to recognise and classify and to the best of our knowledge this is the first case of anomalous origin of the right coronary artery from the pulmonary artery diagnosis in the dog.

Advanced imaging in an adult dog with anomalous origin of the left coronary artery from the pulmonary artery and extensive collateral coronary circulation.

A three-year-old, spayed female, Bichon Frise was diagnosed with an anomalous origin of the left coronary artery from the pulmonary artery, a rare congenital coronary artery defect which has only been reported in two other dogs. Echocardiography was initially performed, though the final diagnosis was made with angiography and computed tomography angiography. An extensive network of collateral coronary circulation allowed for communication between the dilated, tortuous right coronary artery, and the anomalous left coronary artery. Though collateral circulation likely prolonged the patient's life, it is suspected that coronary steal phenomenon and chronic myocardial ischemia ultimately led to fatal ventricular arrhythmias. The dog died suddenly at the age of six, three years after initial diagnosis.

Surgical repair of an unroofed coronary sinus in a dog.

A 5-year-old, 7.9 kg castrated male Miniature Dachsund presented with heart enlargement on radiography. The dog was asymptomatic. Echocardiography revealed a tubular structure running along the posterior wall of the left atrium and connecting to the right atrium on the caudal side of the left atrium and annulus, which was presumed to be a dilated coronary sinus. After confirming a shunt between the left atrium and coronary sinus by cardiovascular catheterization, an unroofed coronary sinus was diagnosed. Open-heart surgery using cardiopulmonary bypass was performed through left atriotomy. The defect between the left atrium and the coronary sinus was closed by suturing. The cardiac enlargement improved after surgery. The dog was still alive 1227 days after surgery without clinical signs.

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.

Single left coronary ostium with a prepulmonic right coronary artery course in a French Bulldog with congenital valvular pulmonary stenosis.

A two-year-old, male castrated, French bulldog was presented for evaluation of coronary artery anatomy before balloon valvuloplasty for severe pulmonic valve stenosis. Multidetector computed tomography angiography showed a single left coronary ostium, absent right coronary ostium, and an anomalous, prepulmonic coursing right coronary artery. Medical management was elected to avoid the attendant risk associated with intervention. This case report documented the first known case of this specific anomaly in French bulldogs. Veterinary cardiologists should be aware of the potential for this specific coronary artery anomaly in this breed, given the predilection for the development of pulmonary stenosis. Routine screening of French bulldogs for anomalous, prepulmonic coronary arteries is recommended before interventional balloon valvuloplasty.

Persistent truncus arteriosus with an anomalous coronary artery in a cat.

A 6-month-old, female, domestic shorthair cat weighing 1.8 kg presented with cardiomegaly seen on radiographs taken at a primary care veterinary center. Echocardiography revealed a single enlarged vessel overriding a ventricular septal defect and severe hypertrophy of the right ventricular free wall. There was no evidence of a pulmonary arterial trunk originating from the heart. The blood flow through the ventricular septal defect exhibited right-to-left shunting. The cat suddenly experienced dyspnea and died at home, and a postmortem examination was performed. A single large vessel was noted leaving the heart, from which the right and left pulmonary arteries arose separately; a main pulmonary artery was absent. There was only one single anomalous coronary ostium that arose from the brachiocephalic artery and divided into two branches. The walls of the extracardiac coronary artery were thick, but neither infarcts nor narrowing was observed within the coronary arteries. There were no abnormalities in the intracardiac coronary artery. These findings revealed a persistent truncus arteriosus with an anomalous coronary artery. A combination of these anomalies might have contributed to the early death of the cat.

Evaluation of non-ECG and ECG-gated computed tomographic angiography for three-dimensional printing of anomalous coronary arteries in dogs with pulmonic stenosis.

INTRODUCTION/OBJECTIVES: Coronary artery abnormalities are described sporadically in dogs, most commonly with pulmonic stenosis. Computed tomographic angiography (CTA) allows non-invasive assessment of coronary anatomy. Three-dimensional (3D) models improve the understanding and visualization of spatially complex anatomy. The study objective was to evaluate coronary artery anomalies using CTA imaging and using rapid prototyping technology to create life-sized coronary artery models of these studies. ANIMALS, MATERIAL AND METHODS: Combined retrospective case and prospective pilot study. Inclusion criteria were dogs with reported coronary artery anomalies. The CTA data sets were imported into a medical imaging framework for the analysis of the coronary arteries and into a 3D-planning and printing software for creating printable 3D models. The 3D models were printed using fusion deposition modeling technology. RESULTS: Six male dogs with an R2A coronary artery anomaly and pulmonic stenosis diagnosed by CTA were included. Electrocardiogram (ECG)-gated CTA allowed better identification of anomalous coronary arteries than non-gated CTA. In all dogs, the right coronary artery had a smaller diameter than the left and the left coronary artery or its branch had a prepulmonic course. All ECG-gated studies were 3D printed while non-gated studies were not printable due to CTA artifacts. CONCLUSION: In dogs, CTA is effective for diagnosis of coronary artery anomalies. Printed 3D models of ECG-gated CTA studies were of excellent quality and allowed direct visualization of abnormal coronary artery anatomy. The usefulness of these models to improve the understanding of anomalous coronary artery anatomy could be evaluated in future studies.

Coronary arteriovenous malformation in a dog with a complex arrhythmia and hypothyroidism.

A four-year-old Japanese Akita was referred for investigation of lethargy, exercise intolerance, and an irregular heart rhythm. He was diagnosed with atrial fibrillation, a complex ventricular arrhythmia, and hypothyroidism. Echocardiography identified a nest of anomalous vessels surrounding the heart and shunting into the pulmonary artery. Computed tomography confirmed a coronary arteriovenous malformation consisting of a coronary-to-pulmonary arterial communication and an associated complex nest of tortuous vessels, which was thought to be an incidental finding. Clinical signs improved with levothyroxine and antiarrhythmic treatment. Describing an unusual coronary artery anomaly as well, this case serves as a reminder to critically evaluate the hemodynamic significance of structural cardiac disease and to screen for systemic disease in patients with arrhythmias.

Non-electrocardiographic-gated computed tomographic angiography can be used to diagnose coronary artery anomalies in Bulldogs with pulmonary valve stenosis.

Coronary artery anomalies have been reported in Bulldogs and present an increased risk when performing balloon valvuloplasty. Identification of coronary anomalies has been reported using multidetector-row computed tomographic (MDCT) angiography with electrocardiographic gating. However, the utility of non-electrocardiographic-gated 16-row computed tomographic for MDCT for the identification of coronary artery anatomy or anomalies to the authors' knowledge has not been fully investigated. The purpose of this study was to evaluate the feasibility of non-electrocardiographic-gated computed tomographic (CT) angiography to identify coronary anomalies in Bulldogs with pulmonary valve stenosis. In this prospective, observational study, Bulldogs with echocardiographically diagnosed pulmonary valve stenosis, an echocardiographically derived transpulmonic pressure gradient >70 mm Hg, and a clinician recommendation for balloon valvuloplasty were included. Anesthetized dogs underwent a 16-row MDCT non-electrocardiographic-gated CT angiography. A board-certified veterinary radiologist and board-certified veterinary cardiologist reviewed the CT angiography studies and identified the coronary artery anatomy. When normal coronary artery anatomy was detected on CT angiography, a right ventricular outflow tract fluoroscopic angiogram was performed and evaluated during levophase to confirm normal coronary anatomy prior to balloon valvuloplasty. Dogs with coronary anomalies noted on CT angiography were recovered from anesthesia and balloon valvuloplasty was not performed. All dogs (10/10; 100%) had interpretable images from the non-electrocardiographic-gated CT angiography. Coronary anomalies were identified in six dogs based on non-electrocardiographic-gated CT angiography, five with type R2A anomaly and one had a single left coronary ostium. Four dogs had normal coronary anatomy based on non-electrocardiographic-gated CT angiography. Balloon valvuloplasty was performed without incident in these four dogs. We conclude that non-electrocardiographic-gated CT angiography represents a noninvasive method for diagnosing coronary anomalies in Bulldogs with pulmonary valve stenosis.

Anomalous origin of the right coronary artery from the pulmonary artery and congenital bicuspid aortic valve in a California sea lion (Zalophus californianus).

A 27-year-old captive female California sea lion (Zalophus californianus) died suddenly. Necropsy findings showed severe hemopericardium, the right coronary artery arose from the sinus of the pulmonary trunk, and the aortic valve was composed of two semilunar cusps. Coronary artery branches emerging from the epicardium were dilated and tortuous. Pampiniform vascular plexus formation existed along the adventitia from the coronal sulcus to the pulmonary trunk. This is the first report of multiple congenital cardiac malformations with an anomalous origin of the right coronary artery from the pulmonary artery and a bicuspid aortic valve in a marine mammal.

Use of ECG-gated computed tomography, echocardiography and selective angiography in five dogs with pulmonic stenosis and one dog with pulmonic stenosis and aberrant coronary arteries.

Pulmonic stenosis (PS) is the most common congenital cardiac disease in dogs. Boxers and English bulldogs are among the most commonly affected breeds and also commonly associated with an aberrant coronary artery (CA). If an aberrant CA is suspected and balloon valvuloplasty indicated, an intra-operative angiography is recommended prior to the procedure. ECG-gated computed tomography (CT) can be used to screen for CA anomalies in a quick and minimally-invasive way (preventing side effects associated with selective catheter angiography) and allowing early planning of the procedure. The aim of this case series was to report CT findings associated with PS diagnosed by echocardiography. Our database was retrospectively searched for cases of dogs with PS diagnosed by echocardiography, where an ECG-gated CT was performed. A total of six cases were retrieved: all were diagnosed with severe PS. Four dogs had concurrent congenital defects: two dogs had a patent ductus arteriosus, one dog had a ventricular septal defect and an overriding aorta, one dog had an aberrant CA. Detailed CT findings of all cases were reported, including one case of a patent ductus arteriosus and an overriding aorta not identified by transthoracic echocardiography. In addition, an abnormal single left coronary ostium, with a pre-pulmonic right CA was described. In conclusion, despite echocardiography remaining the gold standard for diagnosis and assessment of PS, ECG-gated-CT angiography is a complementary diagnostic method that may provide additional relevant information, shorten surgery/anaesthesia time and reduce the amount of radiation to which the clinician is subjected.

Transesophageal echocardiography to diagnose anomalous right coronary artery type R2A in dogs.

OBJECTIVES: To assess the feasibility of transesophageal echocardiography (TEE) as an alternative to angiography for the diagnosis of R2A coronary artery (CA) abnormalities. ANIMALS: Twenty-two dogs with a diagnosis of type R2A CA anomaly were reviewed/analyzed. METHODS: A retrospective study of case records. Transthoracic echocardiography (TTE), transesophageal echocardiography (TEE), angiography, and follow-up investigations of pulmonic stenosis (PS) with R2A CA were carried out to compare different diagnostic methods. RESULTS: Based on the TTE morphology, PS with an aberrant CA was suspected in all dogs (n = 22) and later confirmed by angiography in 18 cases (18/22), and necropsy in two cases (2/22). In 12 cases (12/22), TEE and angiography were both performed and confirmed the diagnosis of an R2A anomaly. Two cases (2/22) were diagnosed only with TEE. CONCLUSIONS: Transesophageal echocardiography may be considered an effective tool to diagnose CA abnormalities, in particular when TTE is inconclusive. Transesophageal echocardiography offers detailed and easily reproducible views of coronary ostia, and the spatial relationship between the right common CA and the great arteries. Although it is not possible to define the course of the more distal coronary branches, TEE has proven reliable in recognizing those elements that can constitute a risk for the execution of a balloon valvuloplasty (BV). Therefore, TEE can be used to confirm this type of CA anomaly and prevent a BV, which is contraindicated in these cases. In addition, TEE avoids any further vascular access, radiation exposure, and contrast medium injection.

Advanced multimodality imaging of an anomalous vessel between the ascending aorta and main pulmonary artery in a dog.

A 1-year-old male German shorthaired pointer was referred for evaluation of tachypnea and hemoptysis. A grade VI/VI left basilar continuous murmur was ausculted. Multimodality imaging consisting of thoracic radiographs, transthoracic and transesophageal echocardiography, fluoroscopy-guided selective angiography, computed tomography angiogram (CTA) and magnetic resonance angiogram (MRA), was performed on this patient. The defect included a left-to-right shunting anomalous vessel between the ascending aorta and main pulmonary artery, along with a dissecting aneurysm of the main and right pulmonary artery. An MRA post-processing technique (PC VIPR) was used to allow for high resolution angiographic images and further assessment of the patient's hemodynamics prior to surgical correction. This case report describes the clinical course of a canine patient with a rare form of congenital cardiac disease, and the multiple imaging modalities that were used to aid in diagnosis and treatment.

Anomalous right coronary artery originating from the left sinus of Valsalva in a Yucatan minipig.

A 39.2-kg, castrated male Yucatan minipig (Sus scrofa domestica) was presented for enrollment in a coronary artery study. Angiography revealed an anomalous right coronary artery originating from the left sinus of Valsalva. The left anterior descending, left circumflex, and anomalous right coronary arteries were implanted with metallic stents without complications. The minipig remained on the study for 3 mo until it reached its predetermined study endpoint, during which time it showed no clinical signs of disease. Histologic examination of the implanted coronary arteries revealed no differences between the normal (left anterior descending and left circumflex arteries) and the anomalous right coronary artery. Swine are important models for coronary research. Although several cases of anomalous human coronary arteries have been documented, the current case is the first report of a coronary artery anomaly in a minipig.

A case of valvular pulmonic stenosis and an aberrant coronary artery in a Brittany spaniel.

Valvular pulmonic stenosis and aberrancy of the right coronary artery with subsequent subvalvular stenosis was found on echocardiographic evaluation of a 9-month-old Brittany spaniel. Previous echocardiography at 4 mo of age revealed the pulmonic stenosis; however, the aberrant coronary artery only became apparent during the second evaluation.

Congenital coronary-pulmonary arterial shunt in a German shepherd dog: diagnosis and surgical correction.

BACKGROUND: A 10 week-old intact female German shepherd dog was examined because of a heart murmur. METHODS: An echocardiogram revealed an extracardiac left-to-right shunt. An angiogram identified shunting between the aorta and the pulmonary artery in an unusual location. RESULTS: Thoracotomy was performed to better identify and correct the lesion; a tubular shunt between the left coronary artery and the pulmonary artery was found and ligated in a closed-heart procedure. The murmur resolved immediately upon ligation and the dog's heart size normalized over a period of several months after surgery. CONCLUSION: In the dog, surgical correction of a coronary artery-pulmonary artery shunt can be performed without complications and can be associated with reversal of cardiac remodeling.