Ablation of ventricular tachycardia in a patient with mechanical double valve replacement - Accessing “hurricane’s eye” in VT-storm

F. Moser (Kiel)¹, L. Rottner (Frankfurt am Main)², I. My (Hamburg)³, M. Lemoine (Hamburg)³, P. Kirchhof (Hamburg)⁴, B. Reißmann (Hamburg)⁵, F. Ouyang (Hamburg)³, A. Metzner (Hamburg)⁶, A. Rillig (Hamburg)^6
1Universitätsklinikum Schleswig-Holstein Innere Medizin III mit den Schwerpunkten Kardiologie, Angiologie und internistische Intensivmedizin Kiel, Deutschland; ²Universitätsklinikum Frankfurt Med. Klinik III - Kardiologie, Angiologie Frankfurt am Main, Deutschland; ³Universitäres Herz- und Gefäßzentrum Hamburg Klinik für Kardiologie Hamburg, Deutschland; ⁴Universitäres Herz- und Gefäßzentrum Hamburg Klinik für Kardiologie Lübeck, Deutschland; ⁵Universitäres Herz- und Gefäßzentrum Hamburg Allgemeine und Interventionelle Kardiologie Hamburg, Deutschland; ⁶Universitäres Herz- und Gefäßzentrum Hamburg Klinik für Kardiologie mit Schwerpunkt Elektrophysiologie Hamburg, Deutschland

Background

Catheter ablation of ventricular tachycardia (VT) in the presence of mechanical aortic and mitral valve replacement can be challenging. We present case of successful endocardial VT ablation of VT storm in a patient without transmitral or retrograde access to the left ventricle (LV) because of mechanical double valve replacement. 

Case presentation

We report on a 68-year-old man that presented to our hospital with VT storm and multiple ICD shocks despite established antiarrhythmic therapy with amiodarone and mexiletine. The patient had ischemic cardiomyopathy with severely reduced left and right ventricular ejection fraction and status post mechanical mitral and aortic valve replacement. Coronary angiography showed no progression of the coronary artery disease. Prior ganglion stellatum blockade had no antiarrhythmic effect. Because of the mechanical valves impeding antegrade and retrograde LV access and potential pericardial adhesions after previous cardiac surgery, the decision was made to perform transapical access. The patient was taken to the EP lab and transapical LV access was established under general anesthesia. LV apex was visualized under fluoroscopy and a 4cm incision in the 5^th intercostal space was made. Thereafter, a steerable sheath was introduced through the transapical access into the LV (Fig. 1). A 3-D electroanatomical map of the left ventricle was created. VT (Cycle length: 340ms, superior Axis, V3-V6 negative) was mechanically induced during mapping, however due to hemodynamic instability, the VT was terminated by external cardioversion and mapping was performed under ventricular stimulation. A low voltage area with fractioned potentials and late potentials could be identified (Fig. 2). Ablation was performed at the borderzone of the substrate and the VT exit site (Fig. 3). Programmed stimulation was performed without VT inducibility after ablation. No peri- or postprocedural complications occurred. At three-month follow-up the patient had no tachycardia recurrence.

Conclusions

This case demonstrates the feasibility of a transapical access for treatment of VT storm when antegrade and retrograde access to the LV endocardium is impeded. A transapical access can be an option for selected patients with mechanical double valve replacement when LV endocardial mapping and ablation is considered in the EP lab.