Page 20 - Journal of Structural Heart Disease Volume 4, Issue 5

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Original Scientific Article
softer coil or an anchoring technique where a dis- tal coil is anchored in a branch vessel then packed proximally [15]. This prevents distal migration and results in a tighter coil pack. An inflated compliant occlusion balloon may be used distal to the coil delivery catheter to prevent unwanted distal em- bolization, especially in high-flow fistulae. Then the balloon can be deflated and withdrawn after the deployment of the first coil that acts as a future basket for further coils [14].
6. The Amplatzer family of devices have been used for percutaneous closure of fistulae. The muscular device, the Duct occlude and the vascular plugs (I, II, IV) all have been used successfully for the clo- sure of these fistulae [16-20]. The advantage of the plugs over the conventional devices is the need for a smaller sheath/catheter for deployment, thus making retrograde delivery possible. For deploy- ment of devices (muscular VSD device or the PDA device), perhaps the best approach is to form an arteriovenous wire loop and deployment of the device from the venous side (see example below). However, for the vascular plugs, it is possible to deploy them from the retrograde approach using the corresponding guide catheter or small delivery sheath.
7. Finally, we want to emphasize the importance of anticoagulation and antiplatelet therapy post de- vice/coil closure of fistulae. As discussed above [11], in some patients intravenous heparin has to be initiated about six hours after closure and bridg- ing to Warfarin and antiplatelet therapy thereafter. This is extremely important to avoid the unfortu- nate complication of thrombus propagation proxi- mal to the devices/coils [21].
Techniques
Fistulae can be closed either in a retrograde fash- ion (approach from the arterial system) or from the venous side (direct access if possible or after estab- lishing an arteriovenous wire loop). Each technique has its own merits.
Retrograde approach
Access should be obtained via the right femoral ar-
tery and vein. We usually insert a 4-5Fr sheath in the artery in children and 6Fr in adults. For the vein, a cor-
responding size can be used. On occasions, we also obtain access in the contralateral femoral artery. We do this if we use a 4-5Fr diagnostic coronary catheter for closure. The purpose of this is to perform control angiography for assessment of the position of coils/ devices prior to release. However, if we use a guide catheter, one may not need additional access. After a careful hemodynamic assessment is performed, selective coronary angiography is performed in the affected coronary artery. Usually, we perform at least two angiograms in different orthogonal views. The purpose of the angiograms is to delineate the exact anatomy of the fistula (origin, course, termination and viable myocardial branches). If the flow is brisk due to the size of fistula, one may need to balloon occlude the fistula with an end-hole balloon cathe- ter advanced over a wire into the fistula and injection via this catheter after removal of the wire. We find this technique to be helpful in delineating the ter- mination site and also in delineating the myocardial branches distal to the balloon (see case below).
Case example:
Four year young female child presented with con- tinuous murmur heard shortly after birth. Echocar- diography revealed the presence of moderate-large sized coronary artery fistula arising from the left an- terior descending artery (LAD) and terminating in the right ventricle. She has been followed conservative- ly until age four years, when it was decided to close it on an elective basis. Her weight was 16.4 kg. A 4Fr sheath was inserted in the right femoral artery and a 5Fr sheath in the right femoral vein. Selective left coronary angiography was performed using a 4Fr JL diagnostic catheter (Figure 1A). Then a 150cmx6cm Excelsior SL-10 Microcatheter (Stryker, Kalamazoo, MI, USA) was inserted inside the JL. The Transend floppy tip guidewire, 0.016” (Stryker, Kalamazoo, MI, USA) was used to navigate the tortuosity of the coronary artery until the wire reached to the right ventricle (Figure 1B). Then over this wire, a 4Fr balloon-tipped catheter was exchanged and positioned in the distal coronary artery. With balloon inflation, hand injec- tion delineated the fistula better (Figure 1C). Then over the same wire, the balloon-tipped catheter was exchanged for the JL and then the Excelsior Microca- theter was fed over this wire all the way to the dis-
Al-Qahtani A. et al.
Catheter Closure of Coronary Fistulae