Three-dimensional and catheter-based intracardiac echocardiographic characterization of the interatrial septum in 2 horses with suspicion of a patent foramen ovale.

This case report describes the 2-dimensional transthoracic (2D-TTE), 3-dimensional transthoracic (3D-TTE) and intracardiac echocardiographic (ICE) characterization of the fossa ovalis region in 2 horses. The first case was presented for poor performance and showed an anechoic zone in the interatrial septum on 2D-TTE. Based on 3D-TTE a deepened fossa ovalis could be identified and using ICE the presence of an interatrial shunt could be excluded. The second case was referred for a cardiac murmur and the presence of turbulent flow in and around the interatrial septum on 2D-TTE color flow Doppler. The complementary use of 2D-TTE, 3D-TTE, and ICE allowed detailed characterization of a patent foramen ovale, with evidence of a left-to-right shunt in a dorsocranial to ventrocaudal direction with limited hemodynamic implications. These 2 cases underline the feasibility of 3D-TTE and ICE in horses and especially show the added value of ICE in a clinical setting.

Transmembrane stent placement for cor triatriatum dexter in six dogs.

OBJECTIVES: Report the long-term outcomes following transmembrane stent placement as a therapy for Cor Triatriatum Dexter (CTD). MATERIALS AND METHODS: Retrospective case series including six dogs with CTD treated with transmembrane stent placement. Follow-up information was obtained including the persistence of presenting clinical signs, additional therapies required, and survival. RESULTS: The median follow-up time was 24 months (range 15-76 months). Long-term outcome was deemed excellent in four dogs (67%), good/fair in one dog (17%), and poor in one dog (17%). Three dogs had persistence of clinical signs of variable severity. These three dogs were Labrador Retrievers or their crosses with varying degrees of tricuspid valve dysplasia (TVD), two of which also had a right to left shunting patent foramen ovale (PFO). One of these three dogs died 23 months post-stent placement during attempted open-heart repair of the TVD and PFO. Another is alive 15 months post-operatively stable on medical therapy for right-sided congestive heart failure secondary to TVD. The final dog demonstrated improved but persistent mild exercise intolerance up to 76 months post-operatively associated with mild TVD and a concurrent PFO. CONCLUSIONS: Transmembrane stent placement for CTD is a viable long-term treatment option with improvement or resolution of clinical signs. In the presence of concurrent congenital heart disease, specifically Labradors with TVD, additional therapies may be necessary with a corresponding impact on prognosis.

Imperforate cor triatriatum dexter with patent foramen ovale and pulmonic stenosis in three dogs: Diagnostic findings and attempted surgical correction.

Three canines were identified with aberrant drainage of the caudal vena cava to the left atrium, consistent with imperforate cor triatriatum dexter, and concurrent patent foramen ovale. All three had concurrent significant pulmonic stenosis with varying degrees of hypoplasia of the right ventricular outflow tract. Echocardiography, positive contrast studies, and angiography confirmed the diagnosis. Surgical redirection of the caudal vena cava bloodflow to the right atrium was attempted unsuccessfully in two symptomatic patients. The third patient was asymptomatic, and correction was not attempted. Possible embryologic causes and possible approaches in future cases are discussed.

An unusual presentation of developmental anomalies of the cardiovascular system including tetralogy of fallot, double outlet right ventricle, patent foramen ovale and persistent right aortic arch in a Friesian calf.

BACKGROUND: Congenital heart diseases are occasionally encountered in the bovine species. Ventricular septal defects (VSD) and atrial septal defects (ASD) are reported to be the most common; however, a vast collection have been reported [1, 2]. Congenital heart diseases is thought to represent less than 3% of all congenital abnormalities in calves [3]. Various cardiac anomalies arise due to defective embryologic development such as defects of the septae or the cardiac chambers [2]. The exact aetiology of these congenial heart anomalies remains to be fully elucidated [4]. VSDs appear to be the most common congenital cardiac anomaly in calves. Other diseases can be subdivided into cyanotic (e.g. ASD or patent ductus arteriosus) and non-cyanotic (e.g. tetralogy of fallot or eisenmengers complex) [5, 6]. An exceptional presentation of an array of congenital anomalies was identified in a Friesian heifer calf. To the authors' knowledge this concurrent collection of congenital abnormalities has never been reported in this species. CASE PRESENTATION: A 3-day old Friesian heifer presented with a history since birth of regurgitation post feeding. The main finding on clinical examination was tachypnoea with a holosystolic murmur. Echocardiography identified a VSD, patent foramen ovale (PFO) (both with left to right blood flow) and tricuspid insufficiency. The calf was subsequently euthanised and underwent gross post-mortem examination. A persistent right aortic arch (PRAA) was identified. The cardiac anomalies identified on the echocardiogram were confirmed along with additional abnormalities; double outlet right ventricle (DORV), partial transposition of the great vessels, pulmonic stenosis, hypoplasia of the right branch of the pulmonary artery and right ventricular hypertrophy. The final diagnosis was Tetralogy of Fallot with DORV, PFO and PRAA. The lungs appeared oedematous and congested due to cardiac malfunction and cranioventral aspiration pneumonia. Free serous fluid was identified in the thoracic cavity. Unilateral renal agenesis of the left kidney was an incidental finding but is of note due to its coexistence with the cardiac abnormalities. CONCLUSIONS: This is an unusual case as it features numerous congenital abnormalities that appeared to negate each other allowing capability with life. To the authors' knowledge, this collection of concurrent cardiac anomalies has not been previously reported in bovines.

Identification of multilevel right-to-left shunting in a dog using nuclear scintigraphy imaging.

A 27-month-old male neutered French bulldog that was originally diagnosed with tricuspid valve dysplasia and a bidirectional shunting patent foramen ovale was evaluated for progressive polycythemia and exertional cyanosis. There was a high clinical suspicion for a right-to-left shunting patent ductus arteriosus, but given the presence of agitated saline within the left atrium, left ventricle, ascending aorta, and abdominal aorta from the previously diagnosed bidirectional shunting patent foramen ovale, a definitive diagnosis could not be made. The use of dynamic and static nuclear scintigraphy imaging using technetium-labeled macroaggregated albumin (99mTc-MAA) allowed a definitive diagnosis to be made in this animal with multilevel right-to-left shunting as well as quantifying the severity of the right-to-left shunt in a minimally invasive and cost-effective manner.

Case report - azygos vein drainage into the left atrium in a dog with cor triatriatum dexter and a patent foramen ovale.

A 2-year-old Airedale terrier was presented with exercise intolerance since birth and newly developed chylous pleural effusion. Imaging procedures including echocardiography, cardiac magnetic resonance imaging, computed tomography, and selective angiography revealed an aberrant connection of the azygos vein and the left atrium, a membrane in the right atrium consistent with cor triatriatum dexter, and a patent foramen ovale with right-to-left shunt. Balloon dilation of the membrane in the right atrium seemed to result in transient improvement of exercise tolerance compared with the previous 2 years. When chylothorax relapsed after three months, the dog was euthanized. Necropsy confirmed the azygos vein to left atrial connection, the patent foramen ovale, and the cor triatriatum dexter.

Combined interventional procedure and cardiopulmonary bypass surgery in a dog with cor triatriatum dexter, patent foramen ovale, and pulmonary stenosis.

A 2-year-old American Pit Bull dog was presented for surgical evaluation of imperforate cor triatriatum dexter (CTD) and patent foramen ovale (PFO). Echocardiography identified an imperforate CTD associated with a right-to-left shunting PFO and valvular pulmonary stenosis. A 2-step interventional and surgical approach was used. Initially, a pulmonary balloon valvuloplasty was performed, and subsequently the dog underwent a surgical correction of the atrial anomaly under cardiopulmonary bypass.

Tricuspid valve dysplasia and a patent foramen ovale resulting in severe tricuspid regurgitation and right-heart dilation in a Red Angus calf.

A two-month-old Red Angus heifer calf presented to the University of Wisconsin Veterinary Care for evaluation of suspected severe bronchopneumonia. Pertinent physical exam findings included tachycardia, tachypnea, dyspnea with a significant abdominal component, and cyanotic mucous membranes. On thoracic auscultation, wheezes were present bilaterally, as well as a grade 2/6 right apical systolic murmur. Thoracic radiographs revealed cardiomegaly, most severely affecting the right side. Echocardiography showed tricuspid valve dysplasia, resulting in severe tricuspid regurgitation and right-heart dilation, as well as a patent foramen ovale. A postmortem examination confirmed the presence of the aforementioned cardiac abnormalities and revealed only mild pulmonary changes. This case report is the first to describe tricuspid dysplasia in the absence of multiple, complex congenital cardiac abnormalities in a calf, and it highlights the value of echocardiography for an antemortem diagnosis.

Tetralogy of Fallot with concurrent patent foramen ovale and tricuspid valve dysplasia in a dog.

The echocardiographic findings of a young Pomeranian-cross dog with tetralogy of Fallot, patent foramen ovale, and tricuspid valve dysplasia are described. Ongoing medical management of hypoxemia and erythrocytosis was carried out and the dog survived to 2 years of age. Treatment options for tetralogy of Fallot are discussed.

Tétralogie de Fallot avec persistance du foramen ovale et dysplasie de la valve tricuspide concomitante chez un chien. Les constatations écho-cardiographiques chez un chien Poméranien de race croisée atteint de la tétralogie de Fallot, de la persistance du foramen ovale et d'une dysplasie de la valve tricuspide sont décrites. Une gestion médicale constante de l'hypoxémie et de l'érythrocytose a été réalisée et le chien a survécu jusqu'à l'âge de 2 ans. Les options de traitement pour la tétralogie de Fallot sont discutées.(Traduit par Isabelle Vallières).

Transcatheter closure of a small atrial septal defect with an Amplatzer™ patent foramen ovale occluder in a working dog with cyanosis and exercise intolerance at high altitude.

A 6.5-year-old male Border Collie presented for transcatheter closure of an atrial septal defect due to exercise intolerance and cyanosis while working and training at altitude. A small, left-to-right shunting secundum atrial septal defect was confirmed with no evidence of significant right-sided volume overload. Pulmonary hypertension with subsequent right-to-left interatrial shunting occurring during exercise at high altitude was suspected and prompted the closure of the defect due to the dog's continued athletic requirements. The anatomy of the defect prompted use of a patent foramen ovale occluder rather than an atrial septal defect occluder, which was deployed using a combination of fluoroscopic and transesophageal echocardiographic guidance. The owner did not report continued exercise intolerance or cyanosis and the dog's lifestyle and residence at altitude was unchanged.

Stent placement for palliation of cor triatriatum dexter in a dog with suspected patent foramen ovale.

An 11 month old spayed, female dog presented with exercise intolerance and cyanosis upon exertion. Echocardiography revealed an imperforate cor triatriatum dexter with mild tricuspid valve dysplasia, an underfilled right ventricle and significant right to left shunting across a presumptive patent foramen ovale. Balloon dilation of the abnormal atrial membrane was initially successful in creating a communication between the right atrial chambers, but stenosis of the original perforation and persistent clinical signs prompted a second intervention. A balloon expandable biliary stent was placed across the abnormal partition, improving caudal venous return to the right ventricle and reducing the right to left shunt. Three months after stent placement, resting oxygen saturation had normalized. Six months after stent placement, exercise tolerance had improved and exertional cyanosis had resolved. Long term follow up will be necessary to assess for remodeling of the right ventricle with improved venous return. Stent placement can be considered as a palliative treatment option for cor triatriatum dexter, especially for stenosis post-balloon dilation.

Stenting of the right ventricular outflow tract in 2 dogs for palliation of dysplastic pulmonary valve stenosis and right-to-left intracardiac shunting defects.

Two dogs with severe dysplastic pulmonary valve stenosis and right-to-left shunting defects (patent foramen ovale, perimembranous ventricular septal defect) underwent palliative stenting of the right ventricular outflow tract and pulmonary valve annulus using balloon expandable stents. One dog received 2 over-lapping bare metal stents placed 7 months apart; the other received a single covered stent. Both procedures were considered technically successful with a reduction in the transpulmonary valve pressure gradient from 202 to 90 mmHg in 1 dog and from 168 to 95 mmHg in the other. Clinical signs of exercise intolerance and syncope were temporarily resolved in both dogs. However, progressive right ventricular concentric hypertrophy, recurrent stenosis, and erythrocytosis were observed over the subsequent 6 months leading to poor long-term outcomes. Stenting of the right ventricular outflow tract is feasible in dogs with severe dysplastic pulmonary valve stenosis, though further study and optimization of the procedure is required.

[Congenital cardiac anomalies (pentalogy of Fallot) in a two year old ram with brachygnathia inferior]. / Kongenitale Herzanomalien (Fallotsche Pentalogie) bei einem zweijährigen Schafbock mit Brachygnathia inferior.

In a nearly two-year-old ram, descending from a breeding trial to investigate the effects of shortness of the lower jaw (brachygnathia inferior), a congenital cardiac anomaly was observed. At the age often months the affected animal, a cross breed of Cameroon Sheep and East Friesian Milk Sheep, showed exercise-induced respiratory distress for the first time. Auscultation revealed a loud systolic heart murmur (grade 5) on both sides of the thorax, most prominent over the left third intercostal space at shoulder height. Postmortem examination of the ram's heart showed a pentalogy of Fallot, consisting of a pulmonic stenosis, a ventricular septal defect, an overriding aorta, a right ventricular hypertrophy and a patent foramen ovale. A genetic defect has to be considered as a possible reason.

Prevalence of patent foramen ovale with right-to-left shunting in dogs with pulmonic stenosis.

BACKGROUND: Right-to-left (R-L) shunt caused by patent foramen ovale (PFO) concurrent with pulmonic stenosis (PS) is considered common, although there is a lack of published evidence. OBJECTIVES: To investigate the prevalence of R-L shunt caused by a PFO in dogs with PS. ANIMALS: Thirty-one client-owned dogs with PS, without obvious extracardiac disease detected on the clinical examinations. METHODS: Case control study: R-L shunt probably caused by PFO was diagnosed when IV injected microbubbles appeared at the left atrial level with an intact atrial septum on echocardiography (bubble-positive dogs). The severity of PS concurrent tricuspid regurgitation (TR), relative thickness of the right ventricle, and relative right atrial area were compared between bubble-positive and bubble-negative dogs. RESULTS: The prevalence of R-L shunts caused by PFO was 39% (12 of 31 cases). The instantaneous pressure gradient (PG) across the pulmonic valve and relative thickness of the right ventricle were significantly increased in bubble-positive compared with those in bubble-negative dogs. None of the dogs with mild or moderate PS (pressure gradient < 80 mm Hg, n = 2) demonstrated R-L shunt. The prevalence of TR in bubble-positive dogs was significantly higher than that in bubble-negative dogs. DISCUSSION AND CLINICAL RELEVANCE: Patent foramen ovale PFO with R-L shunt was more common in dogs with very severe PS and absent in dogs with mild PS.