Acute and Mid-Term Results after Pulmonary Veins Isolation Using a Novel Circular Irrigated Multielectrode Mapping and Ablation Catheter (nMARQ)

Background: Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation in both paroxysmal and persistent AF. However, this procedure is still challenging and time consuming. Objective: The aim of this study was to present our approach for PVI using a novel circular irrigated multielectrode mapping and ablation catheter (nMARQTM) and to present acute and mid-term results. Methods: The study included 31 consecutive patients with symptomatic AF (4 had persistent and 27 had paroxysmal AF) who underwent PVI using the nMARQTM catheter. Circular ablation was guided by CT image integrated into fast anatomical map and by intra cardiac echo. Isolation of pulmonary veins was identified using the nMARQTM catheter if it was possible to advance it into the veins, otherwise Lasso catheter was used. Patients were followed up to 20 months. Results: PVI was achieved in 119 (98%) out of 121 pulmonary veins identified, and final PVI was obtained in 30 (97%) out of 31 patients. Lasso catheter was needed for PVI confirmation in 16 (52%) patients. Touch up ablation using standard catheter guided by Lasso catheter was needed in 4 (13%) patients. Pericardial tamponade occurred in 1 patient who was treated with pericardiocentesis. No other major complications were detected. During follow-up (mean 15.9 ± 3.6 months, range 9 - 20 months), 4 (13%) patients had recurrence of atrial tachyarrhythmia. Conclusion: PVI using the novel nMARQTM catheter is safe with good acute and mid-term efficacy. Long term follow up trials are needed.

Impact of computed tomography image and contact force technology on catheter ablation for atrial fibrillation

AIM:To investigate the impact of using computed tomography(CT) and contact force(CF) technology on recurrence of atrial tachyarrhythmia after atrial fibrillation(AF) ablation.METHODS: This non-randomized study included 2 groups of patients. All patients had symptomatic recurrent paroxysmal or persistent AF and were treated with at least 1 anti arrhythmic medication or intolerant to medication. The first group included 33 patients who underwent circumferential pulmonary veins isolation(PVI) for AF during 2012 and 2013 guided by CT image integration(Cartomerge, Biosense Webster, Diamond Bar, CA, United States) of left atrium and pulmonary veins into an electroanatomic mapping(EAM) system(CT group) using standard irrigated radiofrequency catheter(Thermo Cool, Carto, Biosense Webster, Diamond Bar, CA, United States) or irrigated catheter with integrated CF sensor(Smart Touch, Carto, Biosense Webster, Diamond Bar, CA, United States). The second group included immediately preceding 32 patients who had circumferential PVI by standard irrigated catheter(Thermo Cool) using only EAM(Carto) system(EAM group). Linear lesions were performed according to the discretion of operator. RESULTS: Sex, age, and persistent AF were not different between groups. PVI was achieved in all patients in both groups. Linear ablations including cavo-tricuspid isthmus and or roof line ablation were not different between groups. Free of atrial tachyarrhythmia during follow-up of 24 mo was significantly higher among CT group compared to EAM group(81% vs 55%; respectively; P = 0.027). When 11 patients from CT group who had ablation using Smart Touch catheter were excluded, the difference between CT group and EAM became non significant(73% vs 55%; respectively; P = 0.16). Sub analysis of CT group showed that patients who had ablation using Smart Touch catheter tend to be more free of atrial tachyarrhythmia compared to patients who had ablation using standard irrigated catheter during follow-up(100% vs 73%; respectively; P = 0.07). Major complications(pericardial effusion, cerebrovascular accident/transient ischemic attack, vascular access injury requiring intervention) did not occurred in both groups.CONCLUSION:These preliminary results suggest that CT image integration and CF technology may reduce the recurrence of atrial tachyarrhythmia after catheter ablation for AF.

Improvement in MR and in the dyssynchrony between the mid segments predict super responders in patients undergoing CRT

Background: Twenty to thirty percent of patients with left heart failure in randomized trials do not respond clinically to cardiac resynchronization therapy (CRT). The objectives of our work were to estimate the effec-tiveness of CRT in our routine practice, and to find predictors of favorable response to CRT. Methods: Retrospective analysis of consecutive patients who underwent CRT from 2003-2007. Results: Fifty six consecutive patients (73.2% men, age 66.3 ± 10.2 years) with left heart failure (LHF) (ischemic cardiomyopathy 60.7%) received CRT and were followed for a mean of 27 months. After the implantation: Mean NYHA improved by one class (p < 0.001), LHF admissions were reduced by 79% (p < 0.0001) and mean ejection fruction improved by 31% (19.5% vs 25.6%, p < 0.002). Significant improvement in severity of mitral regurgitation (MR) was an important predictor of high responsiveness (p = 0.004). Improvement of MR was associated with complete left bundle branch block (CLBBB) (p = 0.04) and lower total mortality (p = 0.005). Improvement in synchronization between the mid lateral and mid septal segments, as was calculated with longitudinal strain using echocardiography (105 ± 38 vs 20 ± 23 msec, p = 0.008) was predictor of super responsiveness and reduction in MR among patients with moderate to severe MR prior to implantation. Worsening the delay between the mid posterior and mid anterior septal segments (21 ± 27 vs 120 ± 0 msec, p = 0.006) was associated with absence of response and lack of improvement in MR. Conclusions: Patients who improve mid segments dyssynchrony in four chamber view, have more chance to improve MR and to become super responders.