Transcatheter closure of patent ductus arteriosus in a dog with a peripheral vascular occlusion device

Transjugular Patent Ductus Arteriosus Occlusion in Seven Dogs Using the Amplatzer Vascular Plug II

Simple Summary

This study outlines the authors’ experience using the Amplatzer Vascular Plug II device for occlusion of patent ductus arteriosus (PDA) in dogs through a right transjugular approach, never before described in veterinary medicine for this purpose. The obtained results demonstrate that the use of the Amplatzer Vascular Plug II via a transvenous right jugular approach is a feasible and effective method, even in small-sized patients. The authors’ experience is that the transvenous approach is a safe and effective method for PDA occlusion in dogs. Furthermore, the right jugular approach provides easier and faster vascular access than the femoral one. The authors affirm that this approach, together with the properties of the Amplatzer Vascular Plug II and its wide size selection, potentially provide a novel method that can complement the current available methods for transcatheter PDA occlusion.

Abstract

Although vascular plugs for the closure of patent ductus arteriosus (PDA) have been validated in dogs, studies are lacking on its use as a first-choice device with a transjugular approach. The present case series describes the transvenous right jugular embolization of PDA using an Amplatzer Vascular Plug II in seven dogs of different ages, breeds, and body weights. Complete closure of the PDA was demonstrated in all cases. All dogs showed significant hemodynamic reduction of pulmonary overcirculation and left heart size after the procedure and at following echocardiographic check-ups. Transjugular PDA occlusion using an Amplatzer Vascular Plug II can thus be considered as a safe alternative to the arterial or venous femoral approach using an Amplatzer canine ductal occluder (ACDO), particularly in puppies with small femoral vessels.

Transjugular patent ductus arteriosus occlusion in a cat with a peripheral vascular occlusion device

A five-month-old, intact female domestic shorthair cat was presented to a specialty referral hospital for evaluation of a patent ductus arteriosus. Transvenous embolization of the defect was achieved with a commercially available peripheral vascular plug. The use of vascular plugs for the closure of patent ductus arteriosus has been validated in dogs, yet literature for its use in cats is lacking. The product and procedural details of the device are described.

Jackson-Henderson technique for the revision surgery following PDA rupture in a dog

A 3-month-old female intact Maltese dog, was referred for further investigation and management of a patent ductus arteriosus (PDA), which was diagnosed with a grade V murmur during thoracic auscultation and a palpable thrill in the left third intercostal space during routine vaccination. Echocardiographic findings included left ventricle dilatation, high velocity continuous ductal flow in the pulmonary valve and a patent ductus arteriosus. Hematological and biochemical abnormalities were not detected. A left forth intercostal thoracotomy was performed and during dissection, the medial wall of the duct was perforated resulting in hemorrhage. Digital pressure was applied over the ductus and bleeding ceased. An attempt for further dissection aggravated bleeding so it was decided to abandon surgery and to reoperate the dog using a different technique. Three months after surgery a second procedure was scheduled. A Jackson-Henderson technique was chosen for the ductus ligation, which was completed through a left fourth intercostal thoracotomy and the dog was discharged 2 days postoperatively. The dog was reexamined at 2 and 8 months after surgery and found with no clinical evidence of heart disease. In conclusion the Jackson-Henderson technique was used in the second surgery for closure of the ductus in order to avoid dissection of the medial aspect of the ductus, where adhesions were formed and the dog was free of clinical signs of heart disease 2 and 8 months postoperatively.

Transarterial correction of patent ductus arteriosus in small dogs with the Amplatz™ Vascular Plug 4: A pilot study

OBJECTIVES

Determine if the Amplatz™ Vascular Plug 4 (AVP4) can be used to occlude left-to-right shunting patent ductus arteriosus (PDA) in dogs with inadequate arterial vascular access for the Amplatz Canine Duct Occluder (ACDO).

ANIMALS

Six adolescent dogs with PDA whose femoral artery was too small for insertion of a 4 Fr vascular access sheath.

MATERIALS AND METHODS

Standard femoral arterial vascular access and a 4 Fr diagnostic catheter were used to deploy an appropriately sized AVP4 into the PDA of each dog. Successful occlusion was defined as no residual ductal flow and determined by color Doppler echocardiography and angiography.

RESULTS

The AVP4 was successfully deployed, and complete occlusion of the PDA was achieved in all dogs. There were no complications encountered in any of the dogs.

CONCLUSIONS

The AVP4 is a viable option for the correction of PDA in dogs with inadequate arterial vascular access for the ACDO and should be considered as one of the options available for PDA correction in this challenging animal population.

An experimental canine patent ductus arteriosus occlusion device based on shape memory polymer foam in a nitinol cage

Patent ductus arteriosus (PDA) is a congenital cardiovascular defect in which a fetal connection between the aorta and pulmonary artery does not spontaneously close shortly after birth. If left uncorrected serious complications and even death can occur. Surgical ligation is the traditional treatment method; however, it is an invasive procedure, that motivates development of a minimally invasive option. Shape memory polymer (SMP) foams are unique materials that hold promise in the field of minimally invasive occlusion devices. In this work, a prototype nitinol foam cage (NFC) incorporating SMP foams has been designed and evaluated in multiple mechanical and in vitro verification tests. The NFC demonstrated acceptable fatigue resistance in a preliminary strut integrity test, withstanding one million cycles without complete strut fracture. Radial force analysis of both thick- and thin-walled prototype variations generated less vessel distension and wall tension in a vessel mimic compared to a commercial device. The NFCs exhibited negligible in vitro migration, comparable to that of a commercial device, using simplified, ideal models of PDA. Deployment characteristics of the prototypes were evaluated and compared to that of a commercial device when delivered into physiological models of PDA. During mock deployments, a veterinary cardiologist noted that, while deliverable, the thin-walled NFC prototype exhibited poor deployment characteristics, however the thick-walled NFC had deployment characteristics comparable to that of a commercial device. The promising results of this study warrant further investigation of the NFC device for canine PDA closure.

Alternative methods for the measurement of the minimal ductal diameter of a patent ductus arteriosus in a dog

A two and half-year-old, 24 kg, spayed female German Shepherd was presented for evaluation of a suspected patent ductus arteriosus (PDA). Transthoracic echocardiographic examination confirmed a left to right shunting PDA. Closure of the PDA was recommended, and the owners elected to have minimally invasive transcatheter closure of the PDA performed. Standard ductal angiography failed to provide adequate measurements of the minimal ductal diameter (MDD). Alternative methods of measuring the MDD using an angiography catheter and a balloon catheter were performed. The PDA was occluded using an Amplatz^® Canine Ductal Occluder without complication. Further evaluation of these techniques is needed to determine the accuracy, overall clinical efficacy, and safety of using alternative methods for the measurement of the MDD of a PDA.

Mechanical and in vitro evaluation of an experimental canine patent ductus arteriosus occlusion device

Patent ductus arteriosus (PDA) is a congenital cardiovascular malformation in which a fetal connection between the aorta and pulmonary artery remains patent after birth. This defect commonly results in clinical complications, even death, necessitating closure. Surgical ligation is the most common treatment but requires a thoracotomy and is therefore invasive. A minimally invasive option is preferable. A prototype device for PDA occlusion which utilizes shape memory polymer foams has been developed and evaluated using mechanical and in vitro experiments. Removal force and radial pressure measurements show that the prototype device exhibited a lower removal force and radial pressure than a commercially available device. The in vitro experiments conducted within simplified and physiological PDA models showed that the prototype does not migrate out of position into the pulmonary artery at either physiological or elevated pressures in multiple model configurations. While the radial pressure and removal force were lower than commercial devices, the device performed acceptably in the in vitro benchtop experiments warranting further prototype development.

Minimally invasive per-catheter occlusion and dilation procedures for congenital cardiovascular abnormalities in dogs

With ever-increasing sophistication of veterinary cardiology, minimally invasive per-catheter occlusion and dilation procedures for the treatment of various congenital cardiovascular abnormalities in dogs have become not only available, but mainstream. Much new information about minimally invasive per-catheter patent ductus arteriosus occlusion has been published and presented during the past few years. Consequently, patent ductus arteriosus occlusion is the primary focus of this article. Occlusion of other less common congenital cardiac defects is also briefly reviewed. Balloon dilation of pulmonic stenosis, as well as other congenital obstructive cardiovascular abnormalities is discussed in the latter part of the article.

Intravascular occlusion for the correction of extrahepatic portosystemic shunts in dogs

BACKGROUND

Congential extrahepatic portosystemic shunts (EHPSS) are common in dogs. An effective minimally invasive technique for correction of EHPSS could result in reduced morbidity, reduced costs, and reduced hospitalization times.

HYPOTHESIS

Use of an intravascular occlusion device can effectively and safely result in acute complete occlusion of EHPSS in dogs.

ANIMALS

Seven dogs with naturally occurring EHPSS that presented to the Purdue University Veterinary Teaching Hospital.

METHODS

Prospective, clinical trial. The 7 dogs were consecutively enrolled over a 2-year period. Results of serum biochemistry, total serum bile acids, fasting plasma ammonia, abdominal radiography, and ultrasonography suggested the diagnosis of portosystemic shunts in all dogs. Definitive diagnosis of EHPSS was achieved with cranial mesenteric arterial portography and acute occlusion was attempted by the deployment of the Amplatzer vascular plug (AVP).

RESULTS

EHPSS were identified in all dogs consisting of 5 portocaval and 2 portoazygous variants; 1/7 dogs (14%) were intolerant to temporary complete occlusion of the EHPSS. Of the remaining 6 dogs, 5 (83%) had complete occlusion of the EHPSS by the AVP. There were no complications and resolution of abnormal clinical signs and laboratory values was achieved in 4/5 (80%) dogs with complete occlusion.

CONCLUSIONS AND CLINICAL IMPORTANCE

Intravascular correction of EHPSS by the AVP is a viable option to surgical correction while larger studies will be required to determine the clinical applicability of this procedure in the broader portosystemic shunt population.

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.

The Amplatz canine duct occluder: a novel device for patent ductus arteriosus occlusion

The Amplatz canine duct occluder (ACDO) is a nitinol mesh device with a short waist that separates a flat distal disc from a cupped proximal disc. The device is designed to conform to the morphology of the canine patent ductus arteriosus (PDA). PDA dimensions are determined by angiography, and a guiding catheter is advanced into the main pulmonary artery via the aorta and PDA. An ACDO with a waist diameter approximately twice the angiographic minimal ductal diameter (MDD) is advanced via the catheter using an attached delivery cable until the flat distal disc deploys within the main pulmonary artery. The partially deployed ACDO, guiding catheter, and delivery cable are retracted until the distal disc engages the pulmonic ostium of the PDA. With the delivery cable stabilized, the catheter is retracted to deploy the waist across the pulmonic ostium and cupped proximal disc within the ductal ampulla. Tension on the delivery cable is released, and correct ACDO positioning and stability are confirmed by observing that the device assumes its native shape, back-and-forth maneuvering of the delivery cable, and a small contrast injection made through the guiding catheter. The delivery cable is detached and removed with the guiding catheter. To assess for any residual ductal flow, an angiogram is performed at the conclusion of the procedure, followed by Doppler echocardiography at 1 day and 3 months post-procedure. PDA occlusion in dogs with the ACDO is straightforward and extremely effective across a wide range of body weights, somatotypes, MDDs, and ductal morphologies.