The first percutaneous transluminal closure of a coronary artery fistula was described in 1989 (Nguyen et al. 1989). Mavroudis et al., described conditions for successful embolization as being able to safely cannulate the coronary artery branch supplying the fistula, to protect the mother vessel; to select patients with absence of multiple CAF connections; and the presence of single narrow drainage site into chamber/vessel (Mavroudis et al. 1997). Potential complications with transcatheter embolization include coil migration resulting in distal embolization, coronary spasm, cardiac arrhythmia, fistula dissection and thrombosis (Jama et al. 2011; Armsby et al. 2002).
Balloon assisted embolisation is a common neuro-interventional procedure, first described in 1997 (Moret et al. 1997). For cerebral aneurysms with a large neck, the balloon is inflated across the neck, which stabilizes the coiling microcatheter during coil embolization, and also protects branch vessels arising from the aneurysm neck (Wallace et al. 2019). If using an embolic agent, inflation of a balloon prior to injection, slows the flow into the feeding vessel and thereby reduces the risk of excessive anterograde penetration of the embolic agent (Liang et al. 2013).
Jagadeesan et al. (Jagadeesan et al. 2018b) has previously described the use of a Scepter C dual lumen balloon micro catheter (Microvention, CA, USA) to treat a RCA to PA fistula via a liquid embolic agent (Onyx, Medtronic, MN, USA). We describe the use of the Scepter XC micro catheter (Microvention, CA, USA), which is a dual lumen compliant balloon catheter that has been effectively used in neuro-intervention for cerebral aneurysms (Wallace et al. 2019). The second lumen of a dual lumen catheter accommodates an 0.014 in. diameter microwire which is torquable and steerable in interrogating tortuous vessels (Wallace et al. 2019).
The use of detachable neurovascular coils allows for controlled placement and assessment of flow in non-target vessels prior to deployment. The enhanced potential for navigation of the microwire allows for super-selective interrogation of small feeder vessels which may otherwise be missed due to competitive arterial flow. Therefore the Scepter XC is useful for super-selective interrogation that is useful in tortuous cardiac vessels as in our case.
The compliance of the Scepter XC balloon has previously been documented in the treatment of cerebral vasospasm, where radial expansion of the balloon conforms to the course of the vessel, which allows for balloon inflation that is less traumatic to the vascular architecture to prevent arterial injury and vessel rupture (Heit et al. 2015). The compliant nature of the balloon has also been noted to be useful for angioplasty at branch points in a vessel, where the balloon slightly prolapses into branching vessels, thereby conveying greater stability to the balloon (Heit et al. 2015). This feature is important for stable access in tortuous cardiac anatomy. As in our case, the ability to selectively coil flow related aneurysms while impeding forward flow, allows for more stable placement of the embolic coil.
Furthermore, the balloon and microwire lumens are separate in the Scepter XC micro catheter, which allows for retraction, exchange or reposition of the microwire without losing position of the catheter. This is not possible in a single lumen catheter due to subsequent retrograde blood flow into the balloon that can hamper inflation and deflation of the balloon (Wallace et al. 2019).
A potential shortfall of using the Scepter XC catheter, however, is that the 5 mm nose distal to the balloon can make positioning of the catheter difficult in areas of vessel bifurcation or tortuosity (Heit et al. 2015). Furthermore, the preparation of the Scepter XC balloon, to ensure the absence of air in the device, has been noted to be more time consuming than other balloon catheter devices (Heit et al. 2015). However, these issues did not affect our interventional procedure.
The patient was well at six-month clinical review with improvement in symptoms and no delayed complications.