Po-04-047 bipolar septal ablation in a patient with lamin a/c cardiomyopathy for refractory vt

Ventricular tachycardia (VT) from deep intramural substrate is common patients with Lamin A/C cardiomyopathies and poses a therapeutic challenge. Ablation of deep intramural circuits is challenging due to the thickness of the septum. Bipolar ablation has been used to achieve transmural lesions in patients with septal substrates. We present a case of a septal VT successfully treated with bipolar ablation. To describe the use of bipolar ablation for the treatment of septal VT substrates N/A, case report Case: A 63-year-old male with a past medical history of limb-girdle muscular dystrophy type 1B and non-ischemic cardiomyopathy with an LVEF of 35% secondary to a Lamin A/C mutation, complete heart block with a CRT-D, and recurrent ventricular tachycardia despite antiarrhythmic drugs and three prior ablations presented to us for repeat ablation. The patient had previously undergone two endocardial and one combined endocardial/epicardial ablation for a VT with a right-inferior axis and cycle length of 400 ms. During electrophysiology study, the clinical VT was readily inducible and pace mapping from the right ventricle and a venous septal perforator pointed toward a basal anteroseptal exit. The VT remained inducible despite extensive sequential ablation in the basal septal right and left ventricles and right coronary cusp. Bipolar ablation using two open-irrigation ablation catheters positioned on opposing sides of the basal anterior septum led to complete signal attenuation within a proximal septal perforator and non-inducibility both VTs. The patient remained arrhythmia-free until his heart transplantation procedure three months later. In the figure, panel A shows the clinical VT. Panel B shows pace mapping from the distal poles of an octapolar catheter in a proximal septal venous perforator. Panel C shows the ablation catheter positions. Panel D shows the pathological specimen from the patient’s explanted heart post heart transplantation. The large arrow points to transmural fibrosis at the ablated area and the small arrow to the proximal venous septal perforator. TV is the tricuspid valve and MS is the membranous septum. Septal VTs in non-ischemic cardiomyopathy may have a midmyocardial component which may not be accessible with unipolar ablation. Bipolar ablation may increase procedural success by providing transmural lesions.