Rapid Ventricular Pacing Facilitates Transarterial Embolization in Vein of Galen Malformations

Abstract

Background: Mural type vein of Galen malformation (mVOGM) is a congenital high flow arteriovenous shunt between choroidal arteries and the prosencephalic vein of Markowski leading to heart failure and hydrovenous disorder in children. Embolizing fistulous connections can be challenging and typically requires adjunctive techniques such as induced hypotension, balloon-assisted flow control, and creation of a coil basket. These maneuvers add time, complexity, and unpredictability. Rapid ventricular pacing (RVP) has been proposed as an alternative strategy with fewer drawbacks, but has not been well studied. The approach involves catheterizing the right ventricle with a pacing catheter connected to a temporary external pacemaker. Prior to embolization, RVP is initiated to lower cardiac output. Following embolization, pacing is discontinued, and the heart returns to sinus rhythm. Methods: We performed RVP in five mVOGM patients from 4/2020 through 7/2021. Accounting for multiple procedures, RVP was utilized in ten cases and twenty-six pedicles. Results: Ventricular capture was achieved in all instances and was well tolerated, without arrhythmia. Casting the arterial pedicle with liquid embolic immediately adjacent to, or traversing, the fistulous point was achieved in 9/10 cases. There were no procedural complications. In 1 case, creation of a coil basket in the venous pouch was required to achieve a stable arterial cast Conclusions: This report describes the largest case series utilizing RVP in mVOGM. The technique appears safe and well tolerated.

Rapid ventricular overdrive pacing and other advanced flow-control techniques for the endovascular embolization of vein of galen malformations

“…Defibrillating pads are placed on the patient's chest as a precaution. The pacing catheter is connected to a temporary external pacemaker (19)(20)(21). Just prior to VOGM embolization, RVOP is initiated.…”

“…The corresponding reduction in cardiac output leads to a profound decrease in VOGM circulation, enabling embolization with a markedly decreased risk of venous escape. Following embolization, pacing is discontinued and the heart returns to sinus rhythm (19)(20)(21). RVOP can safely be extended for periods as long as 60 to 90 s, enabling a wide temporal margin for protected embolization.…”

“…In practice however, coil elongation into the flow stream of the shunt often precludes stable anchoring of the coil. More advanced techniques include the concurrent utilization of transarterial and transvenous embolization (9)(10)(11)(12)(13), the use of micro-balloon catheters to suppress arterial flow (14, 15), pharmacologically induced circulatory arrest via cardiac pause (16)(17)(18), and right ventricular overdrive pacing (19)(20)(21). Each technique has advantages and disadvantages and should be employed on a case-dependent basis after careful consideration of specific clinical, anatomical and hemodynamic factors.…”

“…Jones et al ( 20 ) recently reported ten cases of RVOP for VOGM embolization. In their series, ventricular capture was achieved in all cases and was well tolerated without induction of arrhythmia.…”

“…In their series, ventricular capture was achieved in all cases and was well tolerated without induction of arrhythmia. RVOP helped facilitate successful embolization in nine out of the ten VOGMs without any procedural complications ( 20 ).…”