Amplatz catheters

The common angiographic catheter is an important tool for lead extraction. One such catheter is the conunon angled pigtail catheter. This catheter can be used to retrieve and position electrodes by the femoral approach. Other catheters used to assist in lead extraction include a right Judkin s coronary catheter, multipurpose coronary catheter, and Amplatz catheter (Microvena Corp., White Bear Lake, MN). The catheters are usually passed femorally through a sheath. 

The characteristic feature of all Amplatzer devices is the nitinol wire mesh. There are two possible methods of implantation. Either the device is placed entirely into the appendage or the distal disc is expanded in the neck and the proximal disc in the left atrium. The risk of residual shunting around the device is increased when it is totally inserted into the LAA with no part protruding into the atrium. The Amplatzer occluder series holds the widest spectrum of device sizes (4 to 40 mm), The device is attached to a delivery cable and can simply be opened or recollapsed into the delivery catheter. Release is by unscrewing the device after first testing stability with simple traction. 

The use of detachable balloons to occlude the ISV was first described in 1981 [31]. Due to a lack of FDA approval for some of the devices and manufacturer related issues, the balloons have not always been readily available in the USA. From a technical standpoint, balloons were similar to coils in that they needed to be deployed above and below collateral connections. However, since the balloon occluded the vein completely, much like the Amplatz Vascular Plug, only one was necessary at any given site. As with coils, it was common for users of balloons to perform some type of sclerotherapy on the vein segments between balloons to decrease the development of collaterals. Balloons suffered from two major drawbacks that severely limited their more widespread acceptance. The first was cost. The other was that the size of the catheter required to deliver... 

Recanalization of tight occlusions of the left innominate vein, which has a long mediastinal course, as may be caused by mediastinal tumor or fibrosis, can require a combined femoral and axillary or a bilateral axillary approach (Fig. 5.6). When the guidewire has crossed the occlusion, it is grasped with a snare, a basket, or a flexible forceps on the other side, and retrieved through the haemostatic valve sheath at the second percutaneous entry point. This makes it possible to insert a PTA catheter or any other stent delivery catheter over a stiff Amplatz-type guidewire, which is controlled and straightened at both ends. 

When a tight stricture is encountered, but the straight guidewire has passed into the bladder, a 5-F Van Andell is advanced to the bladder and the wire exchanged for a firmer wire such as an Amplatz super-stiff (Boston Scientific), which will allow more pressure to be applied to the subsequent dilators. If these fail to advance, balloon catheters are used. 

After dilatation an Amplatz sheath is inserted over the last dilator. The dilators are then removed leaving only the Amplatz sheath and a guidewire in position. Once the tumor is visualized biopsies are taken both of the tumor and of the apparently normal renal pelvis. The tumor is then resected with diathermy. Tamponade of the tract is maintained with a 30-F nephrostomy catheter. The following day brachytherapy is given to the track to ensure that track tumor implantation does not occur (WooDHOUSE et al. 1986). It is stressed that this treatment is used only for low grade TCC or as... 

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