The first human experience of a contact force sensing catheter for epicardial ablation of ventricular tachycardia

Contact force (CF) is one of the major determinants for sufficient lesion formation. CF-guided procedures are associated with enhanced lesion formation and procedural success.We report our initial experience in epicardial ventricular tachycardia (VT) ablation with a force-sensing catheter using a new approach with an angioplasty balloon. Two patients with arrhythmogenic right ventricular cardiomyopathy who underwent prior unsuccessful endocardial ablation were treated with epicardial VTablation. CF data were used to titrate force, power and ablation time

Clinical experience with a novel subcutaneous implantable defibrillator system in a single center

Background: Implantable cardioverter-defibrillators (ICDs) reduce mortality in both primary and secondary prevention, but are associated with substantial short- and long-term morbidity. A totally subcutaneous ICD (S-ICD) system has been developed. We report the initial clinical experience of the first 31 patients implanted at our hospital. Methods: All patients had an ICD indication according to the ACC/AHA/ESC guidelines. The first 11 patients were part of the reported CE trial. The implantation was performed without fluoroscopy. The device was implanted subcutaneously in the anterior axillary line, with a parasternal lead tunneled from the xiphoid to the manubrial-sternal junction. Ventricular fibrillation (VF) was induced to assess detection accuracy and defibrillation efficacy using 65 J shocks. Results: Post-implant, 52 sustained episodes of VF were induced. Sensitivity was 100% and induced conversion efficacy was 100% (with standard polarity in 29 patients). Mean time to therapy was 13.9 ± 2.5 s (range 11-21.6 s). Late procedure-related complications were observed in 2 of the first 11 implantations (lead migration). During follow-up, spontaneous ventricular arrhythmias occurred in four patients, with accurate detection of all episodes. Inappropriate therapy was observed in five patients. Recurrences were prevented with reprogramming. Conclusions: The S-ICD system can be implanted without the use of fluoroscopy by using anatomical landmarks only. Episodes of VF were accurately detected using subcutaneous signals, and all induced and clinical episodes were successfully converted. The S-ICD system is a viable alternative to conventional ICD systems for selected patients

Clinical outcome of ablation for long-standing persistent atrial fibrillation with or without defragmentation

Objective To assess the outcome and associated risks of atrial defragmentation for the treatment of long-standing persistent atrial fibrillation (LSP-AF). Methods Thirty-seven consecutive patients (60.4±7.3 years; 28 male) suffering from LSP-AF who underwent pulmonary vein isolation (PVI) and linear ablation were compared. All patients were treated with the Stereotaxis magnetic navigation system (MNS). Two groups were distinguished: patients with (n =20) and without (n =17) defragmentation. The primary endpoint of the study was freedom of AF after 12 months. Secondary endpoints were AF termination, procedure time, fluoroscopy time and procedural complications. Complications were divided into two groups: Major (infarction, stroke, major bleeding and tamponade) and minor (fever, pericarditis and inguinal haematoma). Results No difference was seen in freedom of AF between the defragmentation and the non-defragmentation group (56.2 % vs. 40.0%, P=0.344). Procedure times in the defragmentation group were longer; no differences in fluoroscopy times were observed. No major complications occurred. A higher number of minor complications occurred in the defragmentation group (45.0 % vs. 5.9 %, P=0.009). Mean hospital stay was comparable (4.7±2.2 vs. 3.4±0.8 days, P=0.06). Conclusion Our study suggests that complete defragmentation using MNS is associated with a higher number of minor complications and longer procedure times and thus compromises efficiency without improving efficacy

Outcomes of repeat catheter ablation using magnetic navigation or conventional ablation

After initial catheter ablation, repeat procedures could be necessary. This study evaluates the efficacy of the magnetic navigation system (MNS) in repeat catheter ablation as compared with manual conventional techniques (MANs). The results of 163 repeat ablation procedures were analysed. Ablations were performed either using MNS (n 84) or conventional manual ablation (n 79). Procedures were divided into four groups based on the technique used during the initial and repeat ablation procedure: MANMAN (n 66), MANMNS (n 31), MNSMNS (n 53), and MNSMAN (n 13). Three subgroups were analysed: supraventricular tachycardias (SVTs, n 68), atrial fibrillation (AF, n 67), and ventricular tachycardias (VT, n 28). Recurrences were assessed during 19 11 months follow-up. Overall, repeat procedures using MNS were successful in 89.0 as compared with 96.2 in the MAN group (P ns). The overall recurrence rate was significantly lower using MNS (25.0 vs. 41.4, P 0.045). Acute success and recurrence rates for the MANMAN, MANMNS, MNSMNS, and MNSMAN groups were comparable. For the SVT subgroup a higher acute success rate was achieved using MAN (87.9 vs. 100.0, P 0.049). The use of MNS for SVT is associated with longer procedure times (205 82 vs. 172 69 min, P 0.040). For AF procedure and fluoroscopy times were longer (257 72 vs. 185 64, P 0.001; 59.5 19.3 vs. 41.1 18.3 min, P 0.001). Less fluoroscopy was used for MNS-guided VT procedures (22.8 14.7 vs. 41.2 10.9, P 0.011). Our data suggest that overall MNS is comparable with MAN in acute success after repeat catheter ablation. However, MNS is related to fewer recurrences as compared with MAN

Syncope due to idiopathic paroxysmal atrioventricular block : long-term follow-up of a distinct form of atrioventricular block.

We present data on patients with syncope due to paroxysmal atrioventricular (AV) block unexplainable in terms of currently known mechanisms