Catheter Ablation for Ventricular Premature Contraction Triggering Electrical Storm

Case Report

Austin J Clin Cardiolog. 2016; 3(2): 1047.

Catheter Ablation for Ventricular Premature Contraction Triggering Electrical Storm

Lee W-C, Chen H-C, Chen Y-L and Chen M-C*

Division of Cardiology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taiwan

*Corresponding author: Mien-Cheng Chen, Division of Cardiology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, 123 Ta Pei Road, Niao Sung District, Kaohsiung City, 83301, Taiwan

Received: July 16, 2016; Accepted: August 04, 2016; Published: August 05, 2016

Abstract

Electrical storm, defined as =3 episodes of Ventricular Tachycardia (VT) or Ventricular Fibrillation (VF) occurring within 24 hours, is a life-threatening medical emergency. A 73-year-old gentleman, with a history of diabetes mellitus and hypertension, presented with congestive heart failure. An Electrocardiography (ECG) showed borderline ST-T changes over anterior wall and high sequential blood troponin-I levels were noted. Accordingly, non-ST elevation myocardial infarction, Killip III, was diagnosed. Percutaneous coronary intervention was performed with one drug-eluting stent placement into middle left anterior descending artery and two drug-eluting stents placement into proximal-tomiddle right coronary artery under Intra-Aortic Balloon Pumping (IABP) support. Three days later, he experienced electrical storm in spite of amiodarone and lidocaine administration and deep sedation. Extracorporeal Membrane Oxygenation (ECMO) setup was inserted for electrical storm. Bedside lead II ECG showed on ventricular premature beat triggering VF. Therefore, he received radiofrequency catheter ablation under ECMO, IABP and ventilator support. 3D mapping by Ensite Navix mapping system demonstrated border zone along the left posterior fasicle and large scar area distributed across the inferior and anteroseptal wall of left ventricle. Purkinje-like potentials were registered at the border zone. Radiofrequency energy was appiled along the border zone from the inferoposteroseptal to anteroseptal wall of left ventricle till elimination of Purkinje potentials and substrate modification of the border zone. No more VT/VF could be induced by programmed ventricular stimulation after ablation. Subsequently, an Implantable Cardioverter Defibrillator (ICD) was implanted and ICD interrogation did not show any episode of VF/VF during the subsequent 3-month follow-up period.

Keywords: Catheter ablation; Electrical storm; Ventricular fibrillation; Ventricular premature contraction

Introduction

Electrical storm due to Ventricular Tachycardia/Ventricular Fibrillation (VT/VF) is a life-threatening medical emergency and a challenging problem for physicians. Refractory electrical storm can happen even through intensive antiarrhythmic administration, deep sedation and mechanical support. We describe here a case of catheter ablation for ventricular premature contraction triggered VF even under Extracorporeal Membrane Oxygenation (ECMO) and Intra- Aortic Balloon Pumping (IABP) support.

Case Report

A 73-year-old gentleman experienced shortness of breath gradually to orthopnea and bilateral legs edema in recent two months. He had medical history of type 2 diabetes mellitus and hypertension. Electrocardiography (ECG) showed sinus tachycardia, right bundle branch block, and borderline ST-T changes in the leads of anterior wall. High sequential blood troponin-I levels were noted. Non-ST segment elevation myocardial infarction, Killip III, was diagnosed. Chest radiography showed cardiomegaly and pulmonary congestion. IABP was inserted for hemodynamic support before percutaneous coronary intervention. Coronary angiography showed two-vessel coronary artery disease as Left Anterior Descending Artery (LAD) and Right Coronary Artery (RCA) totally occluded (Figure 1A, 1B). Percutaneous coronary intervention was performed with one drug-eluting stent placement into middle-LADafter thrombectomy and two drug-eluting stents placement into proximal- to middle- RCA under intravascular ultrasound guidance. Final coronary angiography showed Thrombolysis In Myocardial Infarction 3 flow in targeted vessels (Figure 1C, 1D). Three days later, ventilator and IABP were removed due to fair hemodynamic condition. Subsequently, he experienced shortness of breath and frequent ventricular tachyarrhythmias. After resuscitation, intubation was reinitiated and IABP was inserted again for frequent unstable ventricular tachyarrhythmias. Bedside lead II ECG monitor showed one Ventricular Premature Contraction (VPC) triggered VF (Figure 2). VF recurred for more than twenty times, in spite of amiodarone and lidocaine administration and fully sedation. ECMO setup was inserted for electrical storm. Repeat coronary angiography showed no significant stenosis over previous stented segments and one bare-metal stent was placed into a borderline lesion of ramus branch. After total revascularization, several episodes of ventricular tachyarrhythmia still recurred after weaning him off lidocaine administration. Therefore, he received radiofrequency catheter ablation for electrical storm.