Bipolar Radiofrequency Ablation of Septal Ventricular Tachycardia Facilitated by an Intramural Catheter

Abstract

Intramural septal substrate presents a challenge in patients undergoing ventricular tachycardia ablation, in terms of both accurate mapping and ablation with unipolar radiofrequency energy. We present the first use of the novel 2-F octapolar catheter in accurately defining intramural septal scar and facilitating bipolar ablation. ( Level of Difficulty: Advanced. )

Successful bipolar radiofrequency catheter ablation in a case of scar-related ventricular tachycardia with intramural critical isthmus in basal posterior right ventricle identified by coherent mapping

“…However, Epi and Endo activation mapping data showed a delay of 70 ms between fairly close Epi and Endo RV surfaces, also suggesting intramural substrate. Other ways of locating intramural substrate are to look for scar in magnetic resonance imaging and direct intramural recording with Bi-ABL, such as performed by Waight and colleagues, 12 who applied this method to scar-related VT originating from the interventricular septum. Direct intramural sampling of substrate was not feasible because of location of the intramural circuit in our patient, but is likely useful in other situations.…”

Bipolar ablation of ventricular arrhythmias: Step‐by‐step

“…To mitigate these challenges, imaging techniques can be useful. Additionally, the use of microcatheters, mapping wires, and 3‐D mapping systems can improve visualization and navigation in these challenging regions 22,28 . Finally, careful planning, close monitoring, and close collaboration with other members of the team are important to optimize the outcomes of bipolar ablation 29 …”

“…However, given the complexity of some patients with refractory arrhythmias, the endpoints of bipolar ablation can differ, and their determination requires an individual assessment. In patients without clear intraprocedural endpoint (difficulties with arrhythmia inducibility), aiming for non‐excitability of intramural foci is an option 28 . However, such an endpoint can lead to prolonged and extensive bipolar ablation which may not be desirable 8 …”

“…In patients without clear intraprocedural endpoint (difficulties with arrhythmia inducibility), aiming for non-excitability of intramural foci is an option. 28 However, such an endpoint can lead to prolonged and extensive bipolar ablation which may not be desirable. 8 As the intramural substrate may progress over time, patients require postablation follow-up with periodical ECGs, Holter monitoring, and interrogation of cardiac devices.…”

Contemporary Management of Complex Ventricular Arrhythmias

“…Direct loss of pacing capture from a diagnostic catheter strategically placed in an intramural septal vein, in close proximity to a scar, has also been used to facilitate – and acutely demonstrate the value of – bipolar ablation in targeting deep septal substrate. [ 98 ]…”