Necrotizing pulmonary arteritis in a dog with patent ductus arteriosus

A 4-month-old, male Cocker Spaniel was examined because of exercise intolerance. A grade IV/V holosystolic diastolic murmur was auscultated. Increased pulmonary arterial pressure was measured via cardiac catheterization. A patent ductus arteriosus (PDA) was diagnosed radio-graphically by injection of contrast media into the sinus of Valsalva with the immediate appearance of contrast in the pulmonary artery. The dog was destroyed at the owner's request. The presence of a PDA was confirmed by necropsy examination. Medial hypertrophy and necrotizing arteritis of muscular pulmonary arteries were observed on histopathologic examination.     

Right to left patent ductus arteriosus,acute bronchointerstitial pneumonia,pulmonary hypertension and cor pulmonale in a foal

Patent ductus arteriosus (PDA) is a rare congenital cardiac defect in foals causing left to right shunting from the aorta to pulmonary artery. In extremely rare conditions, complications with pulmonary hypertension can result in right to left shunting (Eisenmenger's physiology); however, reversed or right to left shunting has not yet been precisely described in PDA-affected equids. This report describes a unique and unusual case of right to left PDA associated with acute respiratory distress syndrome in a 20-day-old male foal. A holosystolic murmur over the tricuspid valve area and adventitious pulmonary sounds respectively on cardiac and thoracic auscultations, caudodorsally interstitial and bronchointerstitial pulmonary opacities on thoracic radiography, right atrial and ventricular dilatations with paradoxical ventricular septal motion, increased ratio of pulmonary artery internal diameter to the aorta and tricuspid valve regurgitation on echocardiography were detected. Post-mortem and histopathological examinations revealed consolidated, dark red and diffusely enlarged lungs with granular appearance, marked enlargement of the right atrium and ventricle, pulmonary artery thickening and enlargement, patency of the ductus arteriosus, hyaline membrane formation, type II pneumocyte proliferation, hypertrophy and thickening of the pulmonary arteries medial layers and right ventricular myocardial cells distortion and hypertrophy. The findings suggest a right to left shunting through the persistent patency of the ductus arteriosus, pulmonary hypertension and cor pulmonale. We proposed pulmonary hypertension associated with bronchointerstitial pneumonia as a cause of this unusual case of PDA with reversed shunt direction.     

Use of transesophageal echocardiography for visualization of the patent ductus arteriosus during transcatheter coil embolization

Transesophageal echocardiography (TEE) enhances our ability to see the patent ductus arteriosus in the dog. The improved visualization may potentially improve our ability to perform transcatheter coil embolization in patients that are more likely to have a successful outcome. This report uses still and video images to detail the specifics of coil embolization as performed with the assistance of TEE and compares the images with those of angiography, surgery and postmortem examination.     

Percutaneous catheter-based treatment of pulmonic stenosis and patent ductus arteriosus in a dog

A 6-months old female German shepherd dog was referred for management of congenital heart disease. A diagnosis of pulmonic stenosis (PS) and patent ductus arteriosus (PDA) was confirmed by Doppler echocardiography and cardiac catheterisation. The conditions were treated during a single cardiac catheterisation procedure using percutaneous techniques. Gianturco coil embolisation was used to close the PDA, and the PS was relieved using a balloon valvuloplasty technique.     

Target-controlled infusion of propofol combined with variable rate infusion of remifentanil for anaesthesia of a dog with patent ductus arteriosus

An 18-month-old Lurcher was anaesthetized for surgical ligation of a patent ductus arteriosus using a target-controlled infusion (TCI) of propofol and a variable rate infusion of remifentanil. Before anaesthesia, radiographic and echocardiographic examination indicated that the dog had left-sided congestive heart failure and impaired left ventricular systolic function. Ramipril and furosemide were administered pre-operatively. Following pre-anaesthetic medication with morphine, 0.5 mg kg(-1), by intramuscular injection, and pre-oxygenation, remifentanil was infused for 5 minutes at 0.2 microg kg(-1) minute(-1), followed by induction of anaesthesia using intravenous propofol administered by TCI, set at a target concentration of 3.5 microg mL(-1) of propofol in blood. Tracheal intubation was performed and 100% oxygen delivered through a non-rebreathing (Bain) system and then a circle system in the operating theatre. Anaesthesia was maintained with propofol and remifentanil, adjusted according to clinical requirements. Peri-operative analgesia consisted of intercostal bupivacaine nerve block, with meloxicam, morphine and remifentanil.     

Transcatheter closure of patent ductus arteriosus using occluding spring coils

The purpose of this study is to report our initial experience with the use of spring coils to close the patent ductus arteriosus in the dog. There are few large-patient series reported in the veterinary literature. Coil closure was attempted in 15 dogs (median weight, 6.5 kg; range, 1.2 to 38.7 kg) presenting with a patent ductus arteriosus between May 1997 and May 1999. Arterial catheterization followed by angiography was used to decide if coil placement was adequate. A 5- or 8-mm embolization coil, depending on the angiographic diameter of the ductus, was delivered, with 1 loop in the pulmonary arterial side and the remainder of the coil in the aortic side of the duct. Additional coils were used if a residual shunt was present, and closure was confirmed by aortography. Patients were discharged the day after the procedure. Successful coil closure, without residual shunt on angiography, was achieved in 11 of 13 dogs in which coils were released. In 6 dogs, a coil embolized to the pulmonary artery. Four of these dogs had successful closure with multiple coils, and 2 others had surgery. None of these dogs experienced adverse effects. In 2 dogs with conical patent ductus arteriosus >5 mm in minimal diameter, coil closure was not done. We conclude that the patent ductus arteriosus size and anatomical shape are crucial in deciding whether coil closure is the method of choice. In selected cases, coil closure represents an elegant alternative to surgical ligation. Although pulmonary embolism occurred commonly, it did not cause any obvious clinical problem.     

Infective endocarditis of the aortic valve in a Border collie dog with patent ductus arteriosus

Infective endocarditis (IE) in dogs with cardiac shunts has not been reported previously. However, we encountered a dog with concurrent patent ductus arteriosus (PDA) and IE. The dog was a 1-year-old, 13.9-kg female Border collie and presented with anorexia, weight loss, pyrexia (40.4°C) and lameness. A continuous murmur with maximal intensity over the left heart base (Levine 5/6) was detected on auscultation. Echocardiography revealed a PDA and severe aortic stenosis (AS) caused by aortic-valve vegetative lesions. Corynebacterium spp. and Bacillus subtilis were isolated from blood cultures. The dog responded to aggressive antibiotic therapy, and the PDA was subsequently surgically corrected. After a series of treatments, the dog showed long-term improvement in clinical status.     

Transthoracic echocardiographic guidance of patent ductus arteriosus occlusion with an Amplatz® Canine Duct Occluder

Placement of an Amplatz Canine Duct Occluder (ACDO) is usually performed by fluoroscopy (Nguyenba and Tobias, 2007). The latter technical approach presents limitations, mostly due to radiation exposure, making this practice dangerous for the patient and operators. In this study, we describe the successful placement of an Amplatz Canine Duct Occluder device by using transthoracic echocardiographic (TTE) guidance, performed on an 11-month-old female mongrel dog with a grade VI/VI continuous heart murmur diagnosed with patent ductus arteriosus (PDA). The TTE is useful in eliminating exposure to radiation and is more versatile than fluoroscopy in conveying real-time detailed information concerning the position of the ACDO.     

Minimally invasive patent ductus arteriosus occlusion in 5 dogs

OBJECTIVE: To report a technique for minimally invasive occlusion of patent ductus arteriosus (PDA) and outcome in 5 dogs. STUDY DESIGN: Clinical cases. Animals: Five, 4-6-month-old, dogs with PDA. MATERIALS AND METHODS: Titanium ligating clips were used for PDA closure in all dogs. Three dogs had video-enhanced mini-thoracotomy PDA occlusion. Two other dogs had thoracoscopic PDA occlusion using a custom-designed thoracoscopy clip applicator. RESULTS: Thoracoscopic PDA occlusion was successful in both dogs in which it was attempted. Complete PDA closure was achieved in 4 dogs. Three months after surgery, the largest dog had residual ductal flow that hemodynamically was insignificant. CONCLUSIONS: Although technically demanding, minimally invasive PDA occlusion is a safe and reliable technique in dogs. Preoperative measurement of the diameter of the PDA is crucial to determine if complete closure with metal clips can be achieved. CLINICAL RELEVANCE: Minimally invasive PDA occlusion should be considered as an alternative to occlusion via conventional thoracotomy.     

Clip ligation for treatment of patent ductus arteriosus occlusion in three cats

Patent ductus arteriosus (PDA) is a rare congenital cardiovascular anomaly in cats. Due to their small body, intercostal thoracotomy is the most common option to close the PDA. However, few reports detail the surgical technique for ligating PDA in kittens. In this case report, three cats weighing 1.4 kg, 1.2 kg, and 2.9 kg were diagnosed PDA. Clip ligation via left fourth intercostal thoracotomy was performed and the cats were successfully treated. Postoperative echocardiography showed no residual flow in any of the cases. This case report highlights clip occlusion for small cats with PDA could be safe and effective.     

Incomplete endothelialization of an intravascular implant and fatal late‐onset bacterial ductal arteritis in a dog with occluded patent ductus arteriosus

An 18‐month‐old male Akita Inu dog developed fever and lameness 8 months after successful transcatheter closure of a patent ductus arteriosus with an Amplatz Canine Duct Occluder (ACDO). Corynebacterium species were cultured from 3 blood samples. Echocardiography showed a vegetative process on the aortic valves. The dog died spontaneously 3 days after development of the initial signs. Necropsy confirmed the presence of bacterial ductal arteritis and myocarditis, and revealed an incomplete endothelialization of the intraductal metal implant. The reason for the lack of (neo)endothelialization of the ACDO remains unknown. We conclude that late‐onset bacterial device‐related ductal arteritis can develop in dogs where the implant is incompletely covered by a protective endothelial layer.     

Right-to-left patent ductus arteriosus with dysplastic left ventricle in a dog

A 6-week-old Siberian Husky pup had an unusual group of congenital heart anomalies that included a right-to-left patent ductus arteriosus, a small left ventricular chamber and ascending aorta, and a dysplastic mitral valve that may have been stenotic. Anomalies were diagnosed, using cardiac catheterization, angiocardiography, and blood gas determinations. Findings were confirmed by postmortem examination.     

Medial insertion of the patent ductus arteriosus characterized by computed tomography angiography in a cat and dog

Surgical ligation of a left-to-right shunting patent ductus arteriosus was attempted in two animals. In both cases, a young cat and dog, ligation was complicated by poor visualization of the ductus resulting in unsuccessful ligation. Post-operatively, both the cat and dog underwent computed tomography angiography to characterize the location and morphology of the patent ductus arteriosus. In both cases, computed tomography angiography revealed a left-to-right shunting patent ductus arteriosus with an insertion location medial to the left pulmonary artery branch compared to the typical location. We hypothesize that this atypical location resulted in a difficult surgical visualization from the left thoracotomy approach. Transvenous coil embolization of the duct from the external jugular vein was performed in both cases and resulted in successful occlusion. Variations in the medial-lateral insertion of the ductus arteriosus may have consequences for surgical intervention. If an atypical location of a patent ductus arteriosus is suspected on transthoracic echocardiography, computed tomography angiography prior to ligation may be useful to further define ductal location and help guide the surgical approach.     

An unusual morphology of patent ductus arteriosus in a dog

A 12-week old, entire female Border terrier weighing 3·5 kg was presented for investigation of a continuous left heart base murmur. The clinical presentation and preoperative echocardiogram were consistent with a standard morphology of patent ductus arteriosus (PDA) but a discrete ductal vessel was not identified during surgical dissection. Surgery had to be abandoned due to deterioration of the patient's condition under general anaesthesia which led to cardiorespiratory arrest and death despite attempts at resuscitation. Necropsy identified a recess within the wall of the aorta communicating with the pulmonary artery via an ostium at the heart base which determined this structure as an intramural PDA. This morphology of PDA is previously unreported. This report demonstrates that an intramural PDA is not readily identifiable surgically because of the absence of a discrete ductal vessel and it is important to appreciate that unusual morphologies of PDA may occur.     

Right-to-left shunting patent ductus arteriosus with pulmonary hypertension in a cat

A 16-month-old, neutered female domestic shorthaired cat had tachypnoea, inappetence and a heart murmur, which had been first detected at eight weeks old. Diagnosis of reverse shunting patent ductus arteriosus and pulmonary hypertension was based on a detailed two-dimensional and Doppler echocardiographic examination. This report documents the clinical and imaging findings in this rare feline condition.     

Cardiogenic hypertrophic osteopathy in a dog with a right-to-left shunting patent ductus arteriosus

A 5-year-old castrated male Shetland Sheepdog was examined because of progressive bilateral hind limb thickening. Cyanosis of the preputial mucous membranes was evident, whereas the oral mucous membranes had a normal color. A well-structured, palisade-like periosteal reaction with no underlying bone destruction was evident on radiographs of the hind limbs. The radiographic changes were consistent with hypertrophic osteopathy (HO). Severe right-sided cardiomegaly was seen on thoracic radiographs, and a diagnosis of patent ductus arteriosus with right-to-left shunting was made by means of echocardiography and contrast echoaortography. The cyanotic heart disease was believed to be the cause of the HO. Hypertrophic osteopathy has been associated with a number of diseases in animals and humans. In humans, congenital heart defects that cause cyanosis are among the most common causes of HO.     

Contrast-enhanced magnetic resonance angiography of patent ductus arteriosus in a dog

Gadolinium-enhanced three-dimensional magnetic resonance angiography is a relatively new technique in the veterinary field. A mature dog with suspected patent ductus arteriosus underwent contrast-enhanced magnetic resonance angiography at 1·0 T with a three-dimensional fast low-angle shot (FLASH) gradient-echo technique. Qualitatively, three-dimensional images of the ductus were particularly clear with surface reconstructions, and ductus diameters were easy to assess in native images. Contrast-enhanced magnetic resonance angiography is a fast, relatively non-invasive procedure that could be particularly useful when non-surgical interventional procedures are anticipated for ductus occlusion.