Patients with long QT syndrome can sometimes present with a ventricular fibrillation (VF) storm. Catheter ablation of culprit premature ventricular complexes responsible for the triggering of the VF episodes may be required in rare cases of electrical storm that do not respond to conventional measures, and this can be life-saving. We describe a case of emergency catheter ablation in a young woman with a normal corrected QT interval, who presented with malignant VF storm for the first time. We also discuss the diagnostic and management challenges involved, as well as the value of genetic testing in refining the diagnosis.
Cardiology ; Catheter Ablation ; methods ; Electrocardiography ; methods ; Female ; Heart Arrest ; genetics ; therapy ; Heterozygote ; Humans ; Long QT Syndrome ; genetics ; Tachycardia, Ventricular ; therapy ; Treatment Outcome ; Ventricular Fibrillation ; therapy ; Ventricular Premature Complexes ; genetics ; therapy ; Young Adult

Current permanent right ventricular and right atrial endocardial pacing leads are implanted utilizing a central lumen stylet. Right ventricular apex pacing initiates an abnormal asynchronous electrical activation pattern, which results in asynchronous ventricular contraction and relaxation. When pacing from right atrial appendage, the conduction time between two atria will be prolonged, which results in heterogeneity for both depolarization and repolarization. Six patients with Class I indication for permanent pacing were implanted with either single chamber or dual chamber pacemaker. The SelectSecure 3830 4-French (Fr) lumenless lead and the SelectSite C304 8.5-Fr steerable catheter-sheath (Medtronic Inc., USA) were used. Pre-selected pacing sites included inter-atrial septum and right ventricular outflow tract, which were defined by ECG and fluoroscopic criteria. All the implanting procedures were successful without complication. Testing results (mean atrial pacing threshold: 0.87 V; mean P wave amplitude: 2.28 mV; mean ventricular pacing threshold: 0.53V; mean R wave amplitude: 8.75 mV) were satisfactory. It is concluded that implantation of a 4-Fr lumenless pacing lead by using a streerable catheter-sheath to achieve inter-atrial septum or right ventricular outflow tract pacing is safe and feasible.
Cardiac Pacing, Artificial/*methods ; Electrodes, Implanted ; Equipment Safety ; Pacemaker, Artificial ; Prosthesis Implantation/methods ; Sick Sinus Syndrome/*therapy

Atrial Fibrillation/surgery* ; Catheter Ablation/adverse effects* ; Heart Septal Defects, Atrial/surgery* ; Humans ; Iatrogenic Disease ; Treatment Outcome

INTRODUCTIONA retrospective case series of acute anterior myocardial infarction (MI) patients complicated by complete atrioventricular block (AVB) treated with acute percutaneous transluminal coronary angioplasty (PTCA).

CLINICAL PICTUREEight patients with anterior MI and complete AVB underwent acute PTCA between 2000 and 2005. Mean onset of complete AVB was 16.6 +/- 16.9 hours from chest pain onset.

TREATMENTAll patients underwent successful PTCA to the left anterior descending artery.

OUTCOMEComplete AVB resolved with PTCA in 88%; mean time of resolution was 89 +/- 144 minutes after revascularisation. One patient had permanent pacemaker implanted at Day 12 after developing an 8-second ventricular standstill during hospitalisation but not pacing-dependent on follow-up. The rhythm on discharge for the other surviving patients was normal sinus rhythm.

CONCLUSIONThis case series suggests that complete AVB complicating anterior MI is reversible with acute PTCA and survivors are not at increased risk of recurrent AVB. Nevertheless, this condition is associated with extensive myocardial damage and high mortality during the acute hospitalisation was not improved with correction of AVB with temporary pacing.

Adult ; Aged ; Angioplasty, Balloon, Coronary ; Anterior Wall Myocardial Infarction ; complications ; therapy ; Atrioventricular Block ; complications ; therapy ; Electrocardiography ; Female ; Humans ; Male ; Middle Aged ; Recovery of Function ; Retrospective Studies

Current permanent fight ventricular and fight atrial endocardial pacing leads are implanted utilizing a central lumen stylet. Right ventricular apex pacing initiates an abnormal asyno chronous electrical activation pattern, which results in asynchronous ventricular contraction and re-laxation. When pacing from right atrial appendage, the conduction time between two atria will be prolonged, which results in heterogeneity for both depolarization and repolarization. Six patients with Class Ⅰ indication for permanent pacing were implanted with either single chamber or dual chamber pacemaker. The SelectSecure 3830 4-French (Fr) lumenless lead and the SelectSite C304 8.5-Fr steerable catheter-sheath (Medtronic Inc., USA) were used. Pre-selected pacing sites included inter-atrial septum and right ventricular outflow tract, which were defined by ECG and fluoroscopic criteria. All the implanting procedures were successful without complication. Testing results (mean atrial pacing threshold: 0.87 V; mean P wave amplitude: 2.28 mV; mean ventricular pacing threshold:0.53V; mean R wave amplitude: 8.75 mV) were satisfactory. It is concluded that implantation of a 4-Fr lumenless pacing lead by using a streerable catheter-sheath to achieve inter-atrial septum or right ventricular outflow tract pacing is safe and feasible.