Complications during catheter-mediated patent ductus arteriosus closure and pulmonary balloon valvuloplasty

Transvenous closure of patent ductus arteriosus with Nit-Occlud® PDA occlusion system in 13 dogs weighing less than 3 kg

INTRODUCTION

Successful closure of patent ductus arteriosus (PDA) can be obtained with surgical ligation or with occlusion via minimally invasive per-catheter techniques. This study was performed to assess feasibility and effectiveness of transjugular PDA occlusion in dogs weighing < 3 kg with a device called Nit-Occlud® PDA.

ANIMALS

Thirteen client-owned dogs.

MATERIALS AND METHODS

This was a retrospective study. Clinical records of dogs that underwent PDA occlusion with a Nit-Occlud® PDA were reviewed. Data collection included patients' signalment, clinical findings, pre- and post-procedure echocardiographic measurements, device size, procedure time and clinical outcome.

RESULTS

The median age of these patients was six months (2.5-38.0 months), with a mean body weight of 2.44 ± 0.43 kg. The mean minimal ductal diameter (MDD) was 1.82 ± 0.43 mm, while the mean ampulla diameter (AD) was 5.51 ± 1.89 mm. Duct closure was successful in 12 cases. Minimal or no residual shunt was observed on echocardiography prior to device release. In one dog, the device was not released owing to unsatisfactory occlusion, prompting an alternative occlusion method. Follow-up echocardiographic examinations showed complete ductal closure and reversed cardiac remodelling in all cases where the device was successfully released.

DISCUSSION

The Nit-Occlud® is deployed through a delivery system with an outer diameter of 4 Fr or 5 Fr, which makes this solution particularly attractive in patients where vascular access is challenging or unfeasible due to the small size of their vessels.

CONCLUSIONS

The Nit-Occlud® PDA appears a feasible and effective occlusion system in small patients weighing <3 kg.

Computed tomographic characteristics of anatomical variations of external and internal jugular veins in dogs

The external jugular vein (EJV) has been commonly used for clinical procedures in veterinary medicine, while the internal jugular vein (IJV) has been used mainly for research. Limited literature regarding anatomical variants in both EJV and IJV is available. The objectives of this descriptive retrospective study were to identify the number of dogs with variations of the jugular veins in canine patients undergoing CT of the head and neck and characterize these variations. Of 1000 dogs, 193 dogs (19.3%) had anatomical variations. Six types of anatomical variations were identified. The most common Type I was the absence of the linguofacial vein (72.0%, n = 139), with the lingual, facial, and maxillary veins entering the EJV at a common branching point. Type II described a variable course of the EJV and IJV, which in some dogs resulted in the absence of the EJV (14.0%, n = 27). Type III was a variable anastomotic loop formed by the linguofacial or maxillary vein cranial or at the junction of the EJV (4.2%, n = 8). In Type IV, the EJV was either suspected to be aplastic or markedly reduced in diameter compared with the contralateral side just distal to its formation (3.6%, n = 7). Type V was found in only six dogs (3.1%) with unilateral differences in the diameter of the IJV. Six of 193 dogs had a combination of more than one variation (Type VI, 3.1%). Type I was significantly observed more frequently in meso- and dolichocephalic breeds. Type II was significantly observed more frequently in brachycephalic breeds.

Application of robot-assisted endoscopic technique in the treatment of patent ductus arteriosus in 106 children

The objective is to evaluate and apply the robot-assisted endoscopic surgical technique for treatment of patent ductus arteriosus (PDA) in children. Clinical data of 106 children with PDA who underwent robot-assisted endoscopic operation were retrospectively analyzed from August, 2020 to March, 2022. Demographic and preoperative data were collected, including the patient's age, weight, diameter of the ductus arteriosus, operation time, length of postoperative hospital stay, postoperative complications and hospitalization cost. The age ranged from 6 months to 12 years with median age of 2.5 years. In addition, the weight ranged from 6.6 kg (kg) to 51.6 kg with median weight of 12.5 kg. Patients who received transcatheter PDA closure were also enrolled during the same period. Clinical features and perioperative data were compared between the two groups. All the 106 cases underwent robotically assisted surgery for PDA ligation. No one was converted to thoracotomy. The length of operation time was 15-84 min, with an average of 39.4 min. There was no obvious bleeding during the operation. The length of postoperative hospital stays were 1-3 days, with an average of 1.1 ± 0.2 days, which was significantly shorter than that of patients underwent transcatheter approach PDA closure (2.2 ± 0.2 days) (p < 0.05). The average hospitalization costs were US$ 8180 in the 106 patients, which were more expensive than that of ones who received transcatheter procedure (US$ 5076 ± 406) (p < 0.05). Only one case was found to have residual ductus shunt during early postoperative follow-up. One case was found with recurrent laryngeal nerve injury. The two cases recovered after 3 months of follow-up. The median duration of follow-up was 12 (1-20) months. No other short-term complications occurred during the follow-up period. Robotic surgical technique for PDA ligation in children is a safe, effective and reliable surgical method with less trauma, faster recovery and fewer surgical risks. This approach should be considered as an option in children patients requiring PDA ligation.

Case Report: Aortic Regurgitation of Postocclusion and Long-Term Outcome Following PDA Correction in an Adult Dog

A 9-year-old intact female Maltese dog was admitted for further evaluation of previously diagnosed patent ductus arteriosus (PDA). The dog showed severe coughing and exercise intolerance. On physical examination, a grade VI/VI continuous heart murmur was auscultated. Thoracic radiography demonstrated cardiomegaly, pulmonary overcirculation, and moderate bronchointerstitial pattern. Echocardiography revealed severe dilation of the left ventricle and atrium, decreased left ventricular contractility, and left-to-right PDA. On electrocardiography (ECG), R amplitude was increased. Computed tomographic angiography revealed type IIA PDA. The serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) concentration was &gt;10,000 pmol/L. Transarterial occlusion was performed and the Amplatz® Canine Duct Occluder was successfully deployed. On echocardiography 48 h after the procedure, aortic regurgitation (AR) and residual ductal flow were noted. Long-term follow-up on clinical signs, physical examination, radiography, echocardiography, ECG, and serum NT-proBNP were evaluated until 30 months after correction of PDA. The clinical indices of physical examination, thoracic radiography, echocardiography, ECG, and serum NT-proBNP concentration were improved, although the postocclusion AR and residual ductal flow persisted. The dog followed up without clinical signs for 41 months following the correction. To our knowledge, this is the first case report to demonstrate quite a long time of follow-up (41 months) in an older dog with transarterial occlusion of PDA with postocclusion AR and residual flow.

Non-cardiogenic pulmonary oedema complicating balloon valvuloplasty and stent angioplasty of severe pulmonary valve stenosis in four dogs

In dogs, balloon valvuloplasty is considered the treatment of choice for severe pulmonary valve stenosis, and this technique is currently performed routinely in specialist referral practices with low morbidity and mortality. Stent angioplasty has also been recently proposed as a viable treatment option. The present case series describes the clinical course of four dogs with severe pulmonary valve stenosis, treated with balloon valvuloplasty or stent angioplasty at four different institutions, which developed non-cardiogenic pulmonary oedema perioperatively after apparently successful dilation of the pulmonary valve. In three cases, there was evidence of some degree of pulmonary hypertension before ballooning. Despite intensive care, the complication proved fatal in three cases. Clinicians should therefore be aware of this life-threatening complication, previously undescribed in dogs.

Fatal acute lung injury after balloon valvuloplasty in a dog with pulmonary stenosis

A one-year-old French Bulldog was referred for the management of a severe form of pulmonary valve stenosis (PS) complicated by right-sided congestive heart failure. Echocardiography showed severe valvular PS with right ventricular concentric hypertrophy, dilatation and severe right atrial enlargement. A pulmonary balloon valvuloplasty (PBV) was performed with a balloon-to-pulmonary annulus ratio of 1.36. Echocardiography immediately after PBV showed a significant reduction in right atrial and ventricular size, improved opening and mobility of the pulmonary valve leaflets, and a 75% reduction in the pulmonary pressure gradient from 158 mmHg pre-operative to 40 mmHg post-operative. The dog recovered well from anesthesia, but 2 h later, it suddenly showed severe respiratory distress. Focus cardiac ultrasound showed increased left cardiac size with echocardiographic signs of high left ventricular filling pressure. Bedside lung ultrasound showed diffuse numerous-to-confluent B lines, compatible with a severe alveolar-interstitial syndrome. The dog was treated with furosemide, helmet continuous positive airway pressure, and then mechanical ventilation but without success. At post-mortem evaluation, histological examination of the lung showed diffuse, severe broncho-alveolar edema with mixed leukocyte, fibrin, and red blood cell infiltrate. Moreover, severe congestion and multifocal alveolar hemorrhages were evident. All findings were compatible with fatal acute lung injury after PBV secondary to pulmonary reperfusion-ischemia injury and increased pulmonary capillary hydrostatic pressure. Based on the present case, acute lung injury should be considered as a rare but serious complication of PBV.

Acute pulmonary edema in a dog with severe pulmonary valve stenosis: A rare complication after balloon valvuloplasty

Pulmonic stenosis is a frequent congenital heart disease in dogs, and the treatment of choice is balloon valvuloplasty which is usually safe and successful. The authors describe for the first time a severe complication after balloon valvuloplasty in a five-month-old dog. After effective treatment, with a considerable drop in right ventricular pressures, the dog developed hypoxemia and dyspnea due to pulmonary edema. The dog underwent intensive care and symptoms improved after a few hours of oxygen therapy, continuous positive airway pressure, and furosemide. Although this event is rare, it could have a large impact on patient survival and should be considered in the treatment of severe pulmonary valve stenosis in the future.

Identification and Clinical Significance of Heart Murmurs in Puppies Involved in Puppy Trade

The detection of a congenital heart defect at purchase is an important step in early detection from a clinical and legal standpoint. Indeed, some cardiac abnormalities may be corrected with surgery, and very often, treatment needs to be performed early before congestive heart failure or irreversible heart damage can occur. From a legal viewpoint, if the defect is revealed in a newly purchased puppy, the buyer may be required to return it and receive compensation. Puppies affected with congenital heart defects are likely to die prematurely, causing emotional suffering to the owner. Furthermore, by considering breed predisposition, early recognition allows breeders to avoid breeding from particular dogs with genetic defects and prevent the continuation of genetic defects in breeding lines. Given gaps in the literature about the recognition of murmurs in the puppy trade, the present article describes how to identify a heart murmur in a puppy during a pre-purchase examination and its significance from a clinical and legal viewpoint. In the canine population, the prevalence of cardiac defects ranges between 0.13 and 1.6%. Pulmonic stenosis is the most common defect found in puppies, followed by patent ductus arteriosus, subaortic stenosis, and ventricular septal defect. On the basis of the above considerations, the veterinarian should recognize and identify the murmur following a protocol for routine examination of puppies involved in trade.

Key considerations in the approach to congenital heart disease in dogs and cats

Congenital heart disease is an important subset of all cardiovascular disease in dogs and cats that is present at birth and most often detected in young animals but can be diagnosed in adulthood. The range of abnormalities that can occur during development of the heart is vast incorporating simple and complex defects, varying degrees of severity and clinical presentations that include heart failure and cyanosis. While some defects do not result in morbidity in an individual animal, others cause severe clinical signs and death at a young age. Advances in imaging and expanding treatment options offer increasingly more possibilities in the diagnosis and management of congenital heart disease which is the focus of this review. The objective is to provide a broad overview of current practice and highlight key aspects to guide practitioners in their approach to congenital heart disease diagnosis and knowledge of available treatment options.

Clinical features and outcome of dogs and cats with bidirectional and continuous right-to-left shunting patent ductus arteriosus

Background

Studies describing the clinical progression of animals with reverse patent ductus arteriosus (PDA) are lacking.

Objectives

To describe the signalment, presenting signs, echocardiographic features, and survival in a group of dogs and cats with bidirectional and continuous right‐to‐left PDA.

Animals

Forty‐six client‐owned animals included, comprising 43 dogs and 3 cats with bidirectional or continuous right‐to‐left PDA.

Methods

Retrospective multicenter study. Medical records and echocardiographic findings reviewed from animals diagnosed with bidirectional or continuous right‐to‐left PDA. Impact of ductal morphology, spectral Doppler flow profile, PCV, sildenafil treatment at presentation, sildenafil dose, severity of pulmonary hypertension, general anesthesia with or without surgery and the presence of right‐sided congestive heart failure (R‐CHF) on crude mortality rate were evaluated via Mantel‐Cox log rank comparison of Kaplan‐Meier survival curves. Univariable and multivariable Cox proportional hazards analysis was performed, and hazard ratio (HR) (95% confidence intervals [CI]) was presented.

Results

Hindlimb collapse was the most common presenting sign in dogs (n = 16). Clinical signs in cats were variable. Median survival time was 626 days in dogs (range 1‐3628 days). Dogs with R‐CHF had a shorter median survival time (58 days vs 1839 days, P = .03). Dogs treated with sildenafil at initial presentation survived longer (1839 days vs 302 days, P = .03), which was the only independent predictor of survival (HR 0.35, CI 0.15‐0.86, P = 0.021).

Conclusions and Clinical Importance

Dogs and cats with reverse PDA have a variable clinical presentation and prognosis. Survival time was longer in animals prescribed sildenafil at diagnosis. Dogs with R‐CHF at presentation have a worse overall outcome.

Novel coronary artery anomaly in a French bulldog with pulmonary stenosis

A 9-month-old French Bulldog with pulmonary stenosis (PS) underwent transthoracic echocardiography (TTE) and electrocardiogram-gated coronary computed tomography angiography (ECG-CCTA) for presurgical planning of pulmonary balloon valvuloplasty (PBV). Transthoracic echocardiography revealed severe PS and identified two distinct coronary ostia (left and right). Electrocardiogram-gated coronary computed tomography angiography showed a circumpulmonary course of the interventricular paraconal coronary artery, which abnormally originated from the right coronary artery. Based on this case report, the echocardiographic identification of two coronary ostia does not rule out a coronary artery anomaly with circumpulmonary course (as previously hypothesized), and coronary computed tomography angiography may be recommended for presurgical planning of PBV in French Bulldogs.