Device Closure of Perimembranous Ventricular Septal Defect by using Amplatzer Ductus Occluder

Introduction:

Ventricular septal defect (VSD) is by far the commonest congenital heart lesion to present in childhood. It accounts for 35% of all in Bristol series1. The lower prevalence in the adult of congenital heart disease is in large part due to spontaneous closure of many defects. The ideal treatment for the hemodynamically significant defect by surgery is well accepted worldwide. Device closure of ventricular septal defect (VSD) is less well accepted and can only be regarded as an option for very selected cases, is available in a small number of centers worldwide2,3. Unlike device closure of atrial septal defect (ASD) and patent ductus arteriosus (PDA), device closure of VSD is still challenging and controversial. Pediatric cardiology unit of the cardiac centre of Combined Military Hospital (CMH) Dhaka accepted that challenge and very difficult and rewarding procedure of perimembranous VSD closure was done with a non-conventional PDA occluder device with 100% occlusion of the shunt. This is another milestone for pediatric cardiac interventions in our country. perimembranous (PM) type at the age of 18 months during a pre-anesthetic check-up for hydrocele surgery. Anesthesiologist referred the case to a paediatric cardiologist for cardiac evaluation. He had a history of recurrent chest infection and failure to thrive but was never evaluated earlier. Echocardiography of the boy revealed a small PM VSD of 4 mm size. He had hydrocele surgery under infective endocarditis prophylaxis and follow up appointment was given after one year. During his follow up, investigations revealed bigger size VSD.He had little weight gain. His chest X-Ray showed mild cardiomegaly with plethoric lungs.
His VSD size, that time, was 4.5 mm on the left ventricular side and 3.3 mm on right ventricular side. As VSD size was not decreasing and the boy was not gaining optimum weight, VSD device closure was planned. But PM VSD occluder was not available in our lab at that moment, so we decided to do it with Amplatzer PDA Occluder.

Equipment required:

1. Amplatzer Ductus Occluder.
2. PDA delivery system complete.
3. Terumo exchange wire.
4. Arterial and venous sheaths.
5. JR catheter.
6. Snare catheter.
7. Pigtail catheter.
8. Noodle wire.
9. Echo color Doppler machine with the TEE probe.
10. Standard pediatric drape.

Procedure: A 5 French (Fr) sheath was introduced to the right femoral vein (RFV). A 4 Fr sheath was placed in a right femoral artery (RFA) and leader catheter to left femoral artery (LFA). LV (Left ventricle) graph was done to locate VSD. AJR-4 catheter was introduced through RFA and VSD was crossed with the help of Terumo wire. JR catheter was forwarded to the main pulmonary artery (MPA) and Terumo wire was replaced with Noodle’s wire. Noodle-wire was than snared with snare catheter forwarded to MPA through a right femoral vein. Noodles wire was than taken out of the body through a right femoral vein, keeping the other end out through right femoral artery. A PDA delivery sheath was then forwarded through a right femoral vein to the aorta and then dropped down to LV by clockwise rotation in a way so that sheath end should point towards LV apex. PDA Ductus Occluder was than loaded to loader with the help of delivery cable and loader was then connected to the delivery sheath. The device was forwarded to LV and disc opened to LV. The whole system was then pulled back to RV and rest of the device released. Transoesophageal echo and fluoroscopy guide were taken.

Discussion:

The procedure for percuteneous closure of VSD with intracardiac device was first attempted by Lock et al
in 1988 and devices originally designed for the closure of other intracardiac defects were used with variable
success rates4,5,6. Device options used for VSD closure were Rashkind device, VSD OS, Amplatzer
VSD Device and Cardio seal. The Amplatzer VSD Occluder has been undergoing clinical trial since 1988
after the animal experiments had shown 100% occlusion and complete endothelialization at three
months 6. In present case we used Amplatzer Ductus Occluder as the VSD was conical in shape with LV
side of 4.5 mm and RV side of 3.3 mm. The procedure was very smooth and no residual shunt was noticed
after implantation.
Transcatheter closure with non conventional device like detachable coil was used in 3 dogs in Azabu University, Japan. The study concluded that transcatheter closure of a small perimembranous VSD with a detachable coil can be achieved without major complications or significant pathologic lesion at the lesion site7. Another study performed in Chicago Children’s Hospital, Chicago, to assess the immediate and mid- term results of transcatheter closure of postinfract muscular VSD using the new Amplatzer Post Infarct Muscular VSD device (PM VSD). The result proved the procedure as effective and safe.  Percutaneaus closure of perimembranous VSD was proved feasible, safe and effective with Amplatzer Septal Occluder in a study conducted in Brazil9. The study concluded that Amplatzer Septal Occluder was suitable to close a wide range of perimembranous VSDs of different sizes and morphologies with good short-term outcomes. Amplatzer Ductus Occluder is a device designed for closure of patent ductus arteriosus (PDA). We used this device in perimembranous VSD as we found VSD size anatomically suitable to be closed with a ductus occluder. Study with this device is not available yet.

Conclusion:

VSD device closure procedure still remains challenging . However, there are a small group of children with defects that are difficult to close surgically and involve substantially higher risk. These defects can be closed with devices. Most of the VSDs in older children are unsuitable for device closure, because they are often associated with aortic valve prolapse or infundibular stenosis. The VSDs where device has a real role are those which are surgically inaccessible or multiple. In our centre we prefer device closure for older infants and children, as surgery is not yet available for most of the cases in our center.