Irina Suman-Horduna

Contemporary outcomes of supraventricular tachycardia ablation in congenital heart disease: a single-center experience in 116 patients.

Background—Remote magnetic navigation–guided ablation with 3-dimensional (3D)-image integration could provide maximum benefit in patients with complex anatomy. We reviewed supraventricular tachycardia (SVT) ablation in adult patients with congenital heart disease to assess the contribution of these technologies. Methods and Results—One hundred fifty-four SVT ablation procedures (228 SVTs) using a 3D-electroanatomic mapping system in 116 adult patients with congenital heart disease (mean age, 41; 76 male) were classified into 3 groups: Group A, manual mapping/ablation (n=60 procedures); Group B, remote magnetic navigation–guided mapping/ablation with normal femoral vein access (49); and Group C, remote magnetic navigation–guided mapping/ablation with difficult access (45). Group A included simple anomalies with less SVTs. Group B comprised predominantly Fontan patients with more SVTs. Group C included more complex defects, such as intra-atrial baffle or interrupted inferior venous access, in which retrograde aortic and superior venous accesses were used exclusively with more frequent use of image integration (97.8%; P<0.001). Acute success was 91.5%, 83.7%, and 82.2%, respectively (P=0.370). In group C, fluoroscopy time was the shortest (median, 4.2 min; P<0.001) despite the longer procedure duration (median, 253 min; P<0.001). SVTs free rates were 80.4%, 82.4%, and 75.8%, respectively (P=0.787) during a mean 20-months follow-up period. Conclusions—The combination of remote magnetic navigation, 3D-image integration, and electroanatomic mapping system facilitated safe and feasible ablation with very low fluoroscopy exposure even in patients with complex anomalies.

Magnetic navigation in adults with atrial isomerism (heterotaxy syndrome) and supraventricular arrhythmias

AIMS We analysed the type and mechanism of supraventricular arrhythmias encountered in a series of symptomatic adults with atrial isomerism undergoing catheter ablation procedures. METHODS AND RESULTS The study population included consecutive adults with atrial isomerism who had previously undergone surgical repair or palliation of the associated anomalies. Patients underwent electrophysiological study for symptomatic arrhythmia in our institution between 2010 and 2012 using magnetic navigation in conjunction with CARTO RMT and three-dimensional (3D) image integration. Eight patients (five females) with a median age of 33 years [interquartile range (IQR) 24-39] were studied. Access to the cardiac chambers of interest was obtained retrogradely via the aorta using remotely navigated magnetic catheters in six patients. Radiofrequency ablation successfully targeted twin atrioventricular (AV) nodal reentrant tachycardia in two patients, atrial fibrillation (AF) in three, focal atrial tachycardia (AT) mainly originating in the left-sided atrium in four patients, and macro-reentrant AT dependent on a right-sided inferior isthmus in three patients. The median fluoroscopy time was 3.0 min (IQR 2-11). After a median follow-up of 10 months (IQR 6-21), five of the ablated patients are free from arrhythmia; two patients experienced episodes of self-terminated AF and AT, respectively, within one month post-ablation; the remaining patient had only non-sustained AT during the electrophysiological study and was managed medically. CONCLUSION Various supraventricular tachycardia mechanisms are possible in adults with heterotaxy syndrome, all potentially amenable to radiofrequency ablation. The use of remote magnetic navigation along with 3D mapping facilitated the procedures and resulted in a short radiation time.

Successful Right Ventricular Tachycardia Ablation in a Patient with Left Ventricular Non-compaction Cardiomyopathy

We report a case of a 67-year old male with a recent diagnosis of left ventricular non-compaction (LVNC), initially presenting with symptomatic ventricular ectopy and runs of non-sustained ventricular tachycardia (VT). This ventricular arrhythmia originated in a structurally normal right ventricle (RV) and was successfully localized and ablated with the aid of the three-dimensional mapping and remote magnetic navigation.

Use of Asymmetric Bidirectional Catheters with Different Curvature Radius for Catheter Ablation of Cardiac Arrhythmias

The impact of recently introduced asymmetric bidirectional ablation catheters on procedural parameters and acute success rates of ablation procedures is unknown.

Arrhythmogenic Right Ventricle in Left Ventricular Non-compaction - In response to "Right Ventricular Ablation as a Therapeutic Option for Left Ventricular Hypertrabeculation / noncompaction".

We welcome Dr Finsterer’s and Dr Stollberger’s interest in our manuscript and their insightful observations. We have recently reported [1] a case of successful mapping and ablation of ventricular tachyarrhythmia in a patient with left ventricular non-compaction (LVNC). The arrhythmia proved to have a rather unusual and unexpected origin, located within a structurally normal right ventricle (RV). Our patient was followed up for one year following his procedure and had no recurrence of symptoms, documented ventricular ectopy (VE) or ventricular tachycardia on Holter monitoring.

Grouped beating in Eisenmenger: Successful localization and ablation of an accelerated idioventricular rhythm from within the Purkinje system

A 33-year old female with a background of Eisenmenger syndrome secondary to multiple congenital muscular ventricular septal defects (VSD) was admitted with a recent history of frequent intermittent palpitations. It was noted that she had an independent accelerated idioventricular rhythm (AIVR), with rates varying between 85-110bpm, which exhibited a repetitive grouped beating pattern. Although generally perceived as benign, in this case this rhythm was drug refractory, was associated with significant compromise to cardiac filling and output and progressed to haemodynamically intolerable sustained ventricular tachyarrhythmia. Successful ablation was performed at the inferior aspect of the residual VSD, from within the Purkinje network.

Remote Navigation for Complex Arrhythmia

Magnetic navigation has been established as an alternative to conventional, manual catheter navigation for invasive electrophysiology interventions about a decade ago. Besides the obvious advantage of radiation protection for the operator who is positioned remotely from the patient, there are additional benefits of steering the tip of a very floppy catheter. This manuscript reviews the published evidence from simple arrhythmias in patients with normal cardiac anatomy to the most complex congenital heart disease. This progress was made possible by the introduction of improved catheters and most importantly irrigated-tip electrodes.

Resynchronization or Proarrhythmia? A Conundrum

A 58-year-old man with a previous history of aortic valve replacement, a significantly dilated left ventricle with severe systolic dysfunction, and previously documented ventricular tachycardia (VT) presented for interrogation of his biventricular implantable cardioverter defibrillator (ICD; Concerto, Medtronic Inc., Minneapolis, MN, USA) after having received six shocks within the preceding 6 weeks. The device was programmed as DDD 70–140 beats/min, sensed atrioventricular (AV) delay at 120 ms, paced AV delay at 150 ms; electrogram (EGM) 1: A tip to A ring; EGM 2: can to right ventricular (RV) ring; ventricular sense response (VSR) on . In terms of tachycardia therapy, a single ventricular fibrillation zone was programmed at 188 beats/min with antitachycardia pacing (ATP) before charging, followed by defibrillation. Interrogation revealed 15 episodes of VT within a period of 6 weeks. Twelve episodes reached detection and three were nonsustained. Of the 12 episodes that reached detection, two were terminated after ATP but prior to the first shock, four with ATP, and six with a single 35-J internal shock. Initiation of three nonsustained episodes and of 10 of 12 episodes requiring therapy coincided with the delivery of biventricular pacing on a ventricular ectopy occurring after an atrialsensed event (As), shown in Figures 1–3. What

Arrhythmogenic Right Ventricle in Left Ventricular Noncompaction - In Response to the Letter to the Editor “Diagnostic Dilemmas for Underlying Pathophysiology of Arrhythmias Originating from the Right Ventricle”

We would like to thank the author for their interest in our manuscript [1] as well as for their considerate comments. Our patient initially presented in another center with ventricular ectopics (VEs) that were mapped and ablated from the right ventricular outflow tract. The second arrhythmia foci had left bundle branch block morphology but different axis, and it was mapped and ablated by us at the base of the RV towards the infero-lateral aspect of the tricuspid annulus. We share the authors’ opinion that in patients with multiple arrhythmia foci from different parts of the RV myocardium ARVD/C should be considered and notably, that was our initial presumptive diagnosis; however, other features should be identified to further support the diagnosis or ARVD/C. The existing diagnostic criteria are based on major and minor points including structural parameters identified on cardiac magnetic resonance (CMR) or 2D echocardiogram, histological features on myocardial biopsy, depolarization or repolarization abnormalities on ECG, often occurring in a context of familial disease [2].

Advanced ablation strategies for management of post-surgical atrial arrhythmias

Post-surgical arrhythmias include a wide range of arrhythmias occurring late after cardiac surgery and represent a complex substrate for catheter ablation either because of extended scar and remodeling or because of limited access to the area of interest. Novel image integration and ablation tools have made the catheter ablation in this population both feasible and successful. We review a structured approach to catheter ablation of post-surgical atrial arrhythmias in various patient cohorts including the most common congenital heart defects.