Prospective evaluation of entrainment mapping as an adjunct to new-generation high-density activation mapping systems of left atrial tachycardias

BACKGROUND Identification of atrial tachycardia (AT) mechanism remains challenging. OBJECTIVE We sought to investigate the added value of entrainment maneuvers (EM) when using new high-density activation mapping (HDAM) technologies for the identification of complex left ATs. METHODS Thirty-six consecutive complex ATs occurring after ablation of persistent atrial fibrillation were prospectively analyzed. The AT mechanism was diagnosed in 2 steps by 2 experts: (1) based on H DAM only (Coherent module, CARTO, Biosense Webster Inc., Irvine, CA) and (2) with additional analysis from EM. RESULTS EM resulted in atrial fibrillation in 1 patient, who was excluded from the analysis. Ten of 11 single loop macroreentries identified by HDAM were confirmed by EM. Only 4 of 14 double loop macroreentries identified by HDAM wereconfirmed by EM (in 10 patients, EM unmasked passive activation of one of the visual cir- cuits). One sole microreentry circuit identified by HDAM was confirmed by EM. A combination of macro- and microreentry circuits was visualized in 3 ATs using H DAM. However, EM revealed passive activation of the visual macroreentrant loop in 2 of these 3 cases. By using HDAM in 6 of 35 ATs (17%), no univocal mechanism could be identified, whereas EM finally enabled the diagnosis of 5 microreentry circuits and 1 macroreentrant AT. All the diagnoses made from EM in addition to HDAM were confirmed by ablation. CONCLUSION Entrainment maneuvers are still useful during mapping of complex left ATs, mostly to differentiate active from passive macroreentrant loops and to demonstrate microreentry circuits

A worldwide survey on incidence, management and prognosis of oesophageal fistula formation following atrial fibrillation catheter ablation: The POTTER-AF study.

AIMS Oesophageal fistula represents a rare but dreadful complication of atrial fibrillation catheter ablation. Data on its incidence, management and outcome are sparse. METHODS AND RESULTS This international multicenter registry investigates the characteristics of oesophageal fistulae after treatment of atrial fibrillation by catheter ablation. A total of 553,729 catheter ablation procedures (radiofrequency: 62.9%, cryoballoon: 36.2%, other modalities: 0.9%) were performed at 214 centers in 35 countries. In 78 centers 138 patients (0.025%, radiofrequency: 0.038%, cryoballoon: 0.0015% (p<0.0001)) were diagnosed with an oesophageal fistula. Periprocedural data were available for 118 patients (85.5%). Following catheter ablation, the median time to symptoms and the median time to diagnosis were 18 (7.75, 25; range: 0-60) days and 21 (15, 29.5; range: 2-63) days, respectively. The median time from symptom onset to oesophageal fistula diagnosis was 3 (1, 9; range: 0-42) days. The most common initial symptom was fever (59.3%). The diagnosis was established by chest computed tomography in 80.2% of patients. Oesophageal surgery was performed in 47.4% and direct endoscopic treatment in 19.8%, and conservative treatment in 32.8% of patients. The overall mortality was 65.8%. Mortality following surgical (51.9%) or endoscopic treatment (56.5%) was significantly lower as compared to conservative management (89.5%) (odds ratio 7.463 (2.414, 23.072) p<0.001). CONCLUSIONS Oesophageal fistula after catheter ablation of atrial fibrillation is rare and occurs mostly with the use of radiofrequency energy rather than cryoenergy. Mortality without surgical or endoscopic intervention is exceedingly high

A recurrent concealed parahisian accessory pathway

This case demonstrates the interest of ablating in the aortic root in case of resistant parahisian accessory pathways with failure of the right side approach. Failure on the right side may be due to fear of creating an AV block of failure to ablate critical fibers in the parahisian position.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Uncommon presentation of a common arrhythmia

This case report demonstrates that atrioventricular and ventricular atrial conduction at rest may be unreliable in assessing the presence of reentrant atrioventricular nodal tachycardia.SCOPUS: ar.jDecretOANoAutActifinfo:eu-repo/semantics/publishe

Wide irregular QRS tachycardia: is there something hidden?

SCOPUS: ar.jDecretOANoAutActifinfo:eu-repo/semantics/publishe

High-resolution parahisian mapping and ablation using microelectrode embedded ablation catheters

Background: Accurate mapping of the compact atrioventricular (AV) node is critical during ablation of a range of arrhythmias. Objective: The purpose of this multicenter prospective study was to test the hypothesis that microelectrode (ME)-embedded catheters more accurately define the near-field compact AV node compared to conventional catheters. Methods: For the mapping phase, detailed AV junction maps were created in 47 patients using an ME-embedded catheter. His electrograms (EGMs) detected by conventional electrodes (Hisc) and by ME (Hisμ) were annotated. For the ablation phase, AV nodal ablation (Qmode 50 W) was performed in 10 patients after pacemaker implantation, with initial Hisc-only ablation in group 1 (n = 6) and initial Hisμ ablation in group 2 (n = 4). For the clinical phase, a prospective registry of parahisian tachycardia using QDOT was obtained. Results: In the mapping phase, 7.0 ± 5.4 Hisc and 8.0 ± 5.6 Hisμ points were acquired per map (n = 47). Hisμ cloud was smaller and more proximally located than Hisc cloud: (99.4 ± 74.7 mm2 vs 197.6 ± 110.6 mm2; P = .0008). Hisμ EGMs had larger amplitudes than Hisc EGMs (0.40 ± 0.38 mV vs 0.16 ± 0.1 mV; P = .0002). In the ablation phase, for group 1: Hisc-only ablation never resulted in AV block, whereas Hisμ ablation resulted in AV block after limited ablation in all patients (after 13.3 ± 9.2 s); and for group 2: Hisμ ablation always resulted in AV block after 1 application (after 14.3 ± 10.3 s). In the clinical phase, a Hisμ-avoidance strategy could avoid AV block in a prospective registry of 11 patients. Conclusion: ME more accurately defines the region of the compact node, and ablation in this region is associated with a high risk for AV block. ME-based mapping has the potential to significantly enhance ablation safety and efficacy.</p

Left bundle branch area pacing as alternative to his bundle pacing for cardiac resynchronisation therapy: a case report.

Case description : A 74-year-old man suffering from severe heart failure (NYHA III – LVEF 28%) associated with left bundle branch block (LBBB) (Figure 1(A)) and uncontrolled permanent atrial fibrillation (AF) despite optimal medical treatment was referred for His ablation and rescue physiological pacing after a first unsuccessful LV lead implantation through the coronary sinus (CS). Careful review of the occluded CS angiogram indeed revealed no side branches. Concordantly, the patient was offered a ‘rescue’ HBP procedure. Using the SelectSecure lead (model 3830) and a C315 His sheath (Both Medtronic, Inc. MN), His mapping (HV ¼ 106ms) and recruitment were easily obtained, unfortunately without LBBB correction

Evaluation of a simple technique aiming at optimizing point-by-point isolation of the left pulmonary veins: a randomized study

AIMS: We sought to evaluate the efficacy and the safety of a simple technique for stabilizing the ablation catheter during anterior pulmonary vein (PV) encirclement in patients ablated for paroxysmal atrial fibrillation. This consisted of bending the ablation catheter in the left atrium, creating a loop that was cautiously advanced together with the long sheath at the ostium and then within the left superior PV. The curve was then progressively released to reach a stable contact with the anterior part of the left PVs. METHODS AND RESULTS: Eighty consecutive patients (age 64 ± 11 years, left atrial diameter 43 ± 8 mm) undergoing 'CLOSE'-guided PV isolation were prospectively randomized into two groups depending on whether the loop technique was used or not. When using the loop technique, the encirclement of the left PVs was shorter [20 min (interquartile range, IQR 17-24) vs. 26 min (IQR 18-33), P < 0.01] with a high rate of first pass isolation [(100%) vs. (97%), P = 0.9] and adenosine proof isolation [(93%) vs. (95%), P = 0.67]. Most specifically, at the anterior part of the left PVs, there were less dislocations [0 (IQR 0-0) vs. 1 (IQR 0-4), P < 0.001], radiofrequency duration was shorter (272 ± 85 s vs. 378 ± 122 s, P < 0.001), force-time integral was higher [524 gs (IQR 427-687) vs. 398 gs (IQR 354-451), P < 0.001], average contact force was higher [20 g (IQR 13-27) vs. 11g (IQR 9-16), P < 0.001], and impedance drop was higher [12 Ω (IQR 9-19) vs. 10 Ω (IQR 7-14), P < 0.001]. CONCLUSION: This study describes a simple technique to facilitate catheter stability at the anterior part of the left PVs, resulting in more efficient left PV encirclement without compromising safety.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Endoscopic evaluation of the esophagus after catheter ablation of atrial fibrillation using contiguous and optimized radiofrequency applications

BACKGROUND: The incidence of endoscopically detected esophageal lesions after pulmonary vein isolation (PVI) is as high as 18%. Intraesophageal temperature rise (ITR) during ablation is a predictor of esophageal injury. OBJECTIVE: The purpose of this study was to describe an ablation strategy aiming to enclose the pulmonary veins with contiguous, stable, and optimized radiofrequency applications (referred to as CLOSE-PVI). We evaluated esophageal and periesophageal injury with endoscopy in patients revealing ITR during CLOSE-PVI. METHODS: Eighty-five patients with ITR during CLOSE-PVI underwent endoscopy of the esophagus (with ultrasound in 38 patients). PVI consisted of contact force (CF)-guided encircling of the veins using 35-W applications, respecting strict criteria of intertag distance (38.5 degrees C). RESULTS: Endoscopy was performed 9 +/- 4 days after PVI. At the posterior wall, median power was 35 W [interquartile range (IQR) 35-35], application time 18 +/- 5 seconds, CF 13 +/- 6g, and AI 403 +/- 38 au. A median of 5 applications [IQR 4-7] per patient over a length of 21.8 +/- 6.8 mm resulted in ITR >38.5 degrees C (median 39.9 degrees C, IQR 39.2 degrees C-41.2 degrees C, range 38.6 degrees C-50.0 degrees C). For these applications, median power was 35 W [IQR 30-35], application time 14 +/- 3 seconds, CF 12 +/- 5g, and AI 351 +/- 38 au. The incidence of esophageal erythema/erosion on endoscopy was 1 of 85 (1.2%) and of ulceration was 0 of 85 (0%). The incidence of mediastinal or esophageal injury on ultrasound was 0 of 38 (0%). CONCLUSION: The occurrence of esophageal or periesophageal injury after CLOSE-PVI is markedly low (1.2%). Absence of esophageal ulceration in patients with ITR suggests that this strategy of delivering contiguous, relatively high-power, and short-duration radiofrequency applications at the posterior wall is safe