scholarly journals Impact of Left Atrial Bipolar Electrogram Voltage on First Pass Pulmonary Vein Isolation During Radiofrequency Catheter Ablation

2020 ◽  
Vol 11 ◽  
Author(s):  
Lohit Garg ◽  
Naga Venkata K. Pothineni ◽  
J. Michael Daw ◽  
Matthew C. Hyman ◽  
Jeffrey Arkles ◽  
...  
Keyword(s):  
Pulmonary Vein ◽  
Pulmonary Vein Isolation ◽  
Left Atrial ◽  
Low Voltage ◽  
Posterior Wall ◽  
Radiofrequency Energy ◽  
First Pass ◽  
The Mean ◽  
The Right ◽  
Electrogram Voltage

BackgroundFirst pass pulmonary vein isolation (PVI) is associated with durable isolation and reduced recurrence of atrial fibrillation (AF).ObjectiveWe sought to investigate the relationship between left atrial electrogram voltage using multielectrode fast automated mapping (ME-FAM) and first pass isolation with radiofrequency ablation.MethodsWe included consecutive patients (pts) undergoing first time ablation for paroxysmal AF (pAF), and compared the voltage characteristics between patients with and without first pass isolation. Left atrium (LA) adjacent to PVs was divided into 6 regions, and mean voltages obtained with ME-FAM (Pentaray, Biosense Webster) in each region and compared. LA electrograms with marked low voltage (<0.5 mV) were identified and the voltage characteristics at the site of difficult isolation was compared to the voltage in adjacent region.ResultsTwenty consecutive patients (10 with first pass and 10 without) with a mean age of 63.3 ± 6.2 years, 65% males, were studied. Difficult isolation occurred on the right PVs in eight pts and left PVs in three pts. The mean voltage in pts without first pass isolation was lower in all 6 regions; posterior wall (1.93 ± 1.46 versus 2.99 ± 2.19; p < 0.001), roof (1.83 ± 2.29 versus 2.47 ± 1.99; p < 0.001), LA-LPV posterior (1.85 ± 3.09 versus 2.99 ± 2.19, p < 0.001), LA-LPV ridge (1.42 ± 1.04 versus 1.91 ± 1.61; p < 0.001), LA-RPV posterior (1.51 ± 1.11 versus 2.30 ± 1.77, p < 0.001) and LA-RPV septum (1.55 ± 1.23 versus 2.31 ± 1.40, p < 0.001). Patients without first pass isolation also had a larger percentage of signal with an amplitude of <0.5 mV for each of the six regions (12.8% versus 7.5%). In addition, the mean voltage at the site of difficult isolation was lower at 8 out of 11 sites compared to mean voltage for remaining electrograms in that region.ConclusionIn patients undergoing PVI for paroxysmal AF, failure in first pass isolation was associated with lower global LA voltage, more marked low amplitude signal (<0.5 mV) and lower local signal voltage at the site with difficult isolation. The results suggest that a greater degree of global and segmental fibrosis may play a role in ease of PV isolation with radiofrequency energy.

scholarly journals Presence of low voltage area predicts atrial tachyarrhythmia inducibility with atrial burst pacing after pulmonary vein isolation

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
S Kawai ◽  
K Nagaoka ◽  
S Takase ◽  
K Sakamoto ◽  
H Ikuta ◽  
...  
Keyword(s):  
Pulmonary Vein ◽  
Pulmonary Vein Isolation ◽  
Left Atrial ◽  
Low Voltage ◽  
Past History ◽  
Univariate Analysis ◽  
Atrial Tachyarrhythmia ◽  
Chads2 Score ◽  
Atrial Capture ◽  
History Of

Abstract Background Induction of atrial fibrillation (AF)/atrial tachycardia (AT) by atrial burst pacing following ablation procedure may reflect the presence of residual substrates in the atria that maintain AF. However, the relation between the inducibility and left atrial low voltage area (LVA) has not been established. Methods Fifty-nine patients (65 years old, 43 males) with persistent AF who underwent pulmonary vein isolation (PVI)-based ablation were studied. All patients underwent left atrial voltage mapping during sinus rhythm and atrial burst pacing after PVI. Atrial burst pacing was performed with 30-beat at an amplitude of 10V from the ostium of the coronary sinus; increasing from 240 to 320 ppm in steps of 20 ppm or failure to 1:1 atrial capture. Inducibility was defined as AF/AT lasting more than 5 minutes following burst pacing. Left atrial LVA and other co-variates were analyzed with regard to burst pacing positivity. Results AF/AT was induced by burst pacing in 23 patients (39%). Univariate analysis revealed that past history of stroke, CHADS2 score and presence of left atrial LVA were significantly associated with the inducibility of AF/AT. Multivariate analysis revealed that only the presence of LVA was associated with the inducibility (OR 1.5: per 10% increase; p=0.04). We focused on the relationship between the extent of LVA and burst positivity. AF/AT inducibility increased as low voltage area increased, and it was as high as 72.7% when low voltage area was more than 20% (P<0.05). Interestingly, induced arrhythmia type was AT rather than AF when low voltage area was more than 20%. Conclusions Presence of left atrial LVA is an independent predictor of atrial tachyarrhythmia inducibility after PVI in patients with persistent AF. A large amount of low voltage area is related to AT inducibility rather than AF. Extent of LVA and burst positivity Funding Acknowledgement Type of funding source: None

scholarly journals Standardized pulmonary vein isolation workflow to enclose veins with contiguous lesions: the multicentre VISTAX trial

EP Europace ◽  
2020 ◽  
Vol 22 (11) ◽  
pp. 1645-1652
Author(s):  
Mattias Duytschaever ◽  
Johan Vijgen ◽  
Tom De Potter ◽  
Daniel Scherr ◽  
Hugo Van Herendael ◽  
...  
Keyword(s):  
Pulmonary Vein ◽  
Pulmonary Vein Isolation ◽  
Randomized Study ◽  
Standard Of Care ◽  
Posterior Wall ◽  
Anterior Wall ◽  
Atrial Arrhythmia ◽  
Clinical Trial Registration ◽  
First Pass

Abstract Aims To evaluate the safety and effectiveness of pulmonary vein isolation in paroxysmal atrial fibrillation (PAF) using a standardized workflow aiming to enclose the veins with contiguous and optimized radiofrequency lesions. Methods and results This multicentre, prospective, non-randomized study was conducted at 17 European sites. Pulmonary vein isolation was guided by VISITAG SURPOINT (VS target ≥550 on the anterior wall; ≥400 on the posterior wall) and intertag distance (≤6 mm). Atrial arrhythmia recurrence was stringently monitored with weekly and symptom-driven transtelephonic monitoring on top of standard-of-care monitoring (24-h Holter and 12-lead electrocardiogram at 3, 6, and 12 months follow-up). Three hundred and forty participants with drug refractory PAF were enrolled. Acute effectiveness (first-pass isolation proof to a 30-min wait period and adenosine challenge) was 82.4% [95% confidence interval (CI) 77.4–86.7%]. At 12-month follow-up, the rate of freedom from any documented atrial arrhythmia was 78.3% (95% CI 73.8–82.8%), while freedom from atrial arrhythmia by standard-of-care monitoring was 89.4% (95% CI 78.8–87.0%). Freedom fromrepeat ablations by the Kaplan–Meier analysis was 90.4% during 12 months of follow-up. Of the 34 patients with repeat ablations, 14 (41.2%) demonstrated full isolation of all pulmonary vein circles. Primary adverse event (PAE) rate was 3.6% (95% CI 1.9–6.3%). Conclusions The VISTAX trial demonstrated that a standardized PAF ablation workflow aiming for contiguous lesions leads to low rates of PAEs, high acute first-pass isolation rates, and 12-month freedom from arrhythmias approaching 80%. Further research is needed to improve the reproducibility of the outcomes across a wider range of centres. Clinical trial registration: ClinicalTrials.gov, number NCT03062046, https://clinicaltrials.gov/ct2/show/NCT03062046.

P1415Wide antral circumferential pulmonary vein isolation ablation using a novel balloon cryoablation catheter

EP Europace ◽  
2020 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
A P Martin ◽  
M Fowler ◽  
N Lever
Keyword(s):  
Atrial Fibrillation ◽  
Left Atrium ◽  
Pulmonary Vein ◽  
Pulmonary Vein Isolation ◽  
Paroxysmal Atrial Fibrillation ◽  
Left Atrial ◽  
Pulmonary Veins ◽  
Posterior Wall ◽  
The Novel ◽  
Median Treatment

Abstract Background Pulmonary vein isolation using cryotherapy is an established treatment for the management of patients with paroxysmal atrial fibrillation. Ablation using the commercially available balloon cryocatheter has been shown to create wide antral pulmonary vein isolation. A novel balloon cryocatheter (BCC) has been designed to maintain uniform pressure and size during ablation, potentially improving contact with the antral anatomy. The extent of ablation created using the novel BCC has not previously been established. Purpose To determine the anatomical extent of pulmonary vein isolation using electroanatomical mapping when performing catheter ablation for paroxysmal atrial fibrillation using the novel BCC. Methods Nine consecutive patients underwent pre-procedure computed tomography angiography of the left atrium to quantify the chamber dimensions. An electroanatomical map was created using the cryoablation system mapping catheter and a high definition mapping system. A bipolar voltage map was obtained following ablation to determine the extent of pulmonary vein isolation ablation. A volumetric technique was used to quantify the extent of vein and posterior wall electrical isolation in addition to traditional techniques for proving entrance and exit block. Results All patients had paroxysmal atrial fibrillation, mean age 56 years, 7 (78%) male. Electrical isolation was achieved for 100% of the pulmonary veins; mean total procedure time was 109 min (+/- 26 SD), and fluoroscopy time 14.9 min (+/- 2.4 SD). The median treatment applications per vein was one (range one - four), and median treatment duration 180 sec (range 180 -240). Left atrial volume 32 mL/m2 (+/- 7 SD), and mean left atrial posterior wall area 22 cm2 (+/- 4 SD). Data was available for quantitative assessment of the extent of ablation for eight patients. No lesions (0 of 32) were ostial in nature. The antral surface area of ablation was not statistically different between the left and right sided pulmonary veins (p 0.63), which were 5.9 (1.6 SD) and 5.4 (2.1 SD) cm2 respectively. In total 50% of the posterior left atrial wall was ablated.  Conclusion Pulmonary vein isolation using a novel BCC provides a wide and antral lesion set. There is significant debulking of the posterior wall of the left atrium. Abstract Figure.

664Local catheter impedance drop during pulmonary vein isolation predicts conduction block in patients with paroxysmal atrial fibrillation: initial results of the LOCALIZE clinical trial

EP Europace ◽  
2020 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
M Das ◽  
A Luik ◽  
E Shepherd ◽  
M Sulkin ◽  
J Laughner ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Pulmonary Vein ◽  
Pulmonary Vein Isolation ◽  
Roc Analysis ◽  
De Novo ◽  
Conduction Block ◽  
Posterior Wall ◽  
Mapping Procedure ◽  
Index Procedure ◽  
First Pass

Abstract Funding Acknowledgements Boston Scientific Background Radiofrequency (RF) catheter ablation for pulmonary vein isolation (PVI) requires resistively heating cardiac tissue to create conduction block. Creation of an RF lesion results in an impedance drop and the magnitude of this drop depends on the temperature and amount of myocardium being heated. Pre-clinical and clinical evaluation of an advanced local impedance (LI) metric found that greater LI drops were indicative of more effective lesion formation. Purpose To evaluate whether LI drop is associated with conduction block after first pass encirclement of the PVs in patients with paroxysmal AF. Methods LOCALIZE is an ongoing, single-arm, multi-center clinical trial (clinicaltrials.gov NCT03232645). LOCALIZE consists of an index PVI procedure (results presented here) and a 3-month follow-up mapping procedure. In the index procedure, electroanatomical maps of the left atrium were created and ipsilateral PVs were divided into 8 anatomical segments (n = 16 per patient). PVI was performed using point-by-point ablation with blinding of operators to LI. Following initial encirclement and a 20-minute wait period, coronary sinus-paced electroanatomical maps were created to identify gaps within anatomical segments. Gaps were annotated on the map and subsequently ablated. Mean LI drop within each segment was calculated offline as an estimate of regional RF energy delivery (Figure - Left). The diagnostic accuracy of LI drop for predicting segment block was assessed using receiver operating characteristic (ROC) analysis in segments with inter-lesion spacing ≤6mm. Results Forty-seven patients with paroxysmal AF underwent PVI at 5 centers (age 62 ± 11 years, male 55.3%). All patients left the index procedure with all PVs isolated. When blinded to LI (n = 3,064 ablations), median baseline LI was 106 (IQR: 97-115) Ω and median LI drop was 18.4 (12.7-24.9) Ω. After first pass encirclement, blocked segments had a significantly larger LI drop (20.2 [14.6-26.0] Ω) than segments with gaps (10.6 [6.9-15.1] Ω, p < 0.01, Figure - Right). The association between LI drop and block was further evaluated along anatomical anterior/posterior wall thickness differences. Anterior block segments were found to have significantly larger LI drops (21.0 [15.9-27.2] Ω) than posterior block segments (16.6 [12.7-23.7] Ω, p < 0.01). ROC analysis of segments with inter-lesion spacing ≤6mm identified optimal LI cut-off values of 16Ω in anterior segments and 11Ω posteriorly, which had positive predictive values for conduction block of 95.6% and 96.7%, respectively. Conclusions The magnitude of LI drop is predictive of acute PVI segment conduction block in patients with paroxysmal AF. The thinner posterior wall required smaller LI drops for block compared to the thicker anterior wall. With inter-lesion spacing of ≤6mm, reaching a LI drop of ≥16Ω anteriorly and ≥11Ω posteriorly was highly predictive of acute segment block in de novo PVI. Abstract Figure. Local impedance drop in de novo PVI

scholarly journals The role of left atrial wall thickness and pulmonary vein anatomy in success of pulmonary vein isolation using the CLOSE protocol

2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
M Boussoussou ◽  
B Vattay ◽  
B Szilveszter ◽  
M Kolossvary ◽  
M Vecsey-Nagy ◽  
...  
Keyword(s):  
Pulmonary Vein ◽  
Wall Thickness ◽  
Left Atrial ◽  
Pulmonary Veins ◽  
Logistic Regression Models ◽  
Funding Sources ◽  
Coronary Ct ◽  
First Pass ◽  
Procedural Success ◽  
The Right

Abstract Introduction The CLOSE protocol is a novel contact-force guided technique for enclosing pulmonary veins in patients with atrial fibrillation (AF). Consistency and lesion contiguity are essential factors for procedural success. We sought to determine whether left atrial (LA) wall thickness (LAWT) and pulmonary vein (PV) dimensions as assessed by coronary CT angiography (CTA) could influence the efficacy of successful first-pass isolation using the CLOSE protocol. Methods In a single center, prospective study we enrolled 94 patients with symptomatic, drug-refractory AF who underwent pre-ablation left atrial CTA and initial radiofrequency catheter ablation between 2019.01–2020.09. The LA was divided into 11 regions when assessing LAWT. Additionally, the diameter and area of the PV orifices were obtained. First pass isolation was recorded separately for the right and left PVs. After the first pass ablation circles were ready, additional ablations were applied in those cases where first pass isolation was not achieved, to reach complete PV isolation. Predictors of successful first pass isolation were determined using logistic regression models that included anthropometrical, echocardiographic and CTA derived parameters. Results A total of 94 patients were included in the analysis with mean CHA2DS2-VASc score of 2.1±1.5 (mean age 62.4±12.6 years, 39.5% female). 61.7% were paroxysmal, 38.3 were persistent AF patients. Mean procedure times were 81.2±19.3 minutes. Complete isolation of all four PVs was achieved in 100% of patients. First-pass isolation rate was 76%, 71% and 54%, for the right PVs, left PVs and all four PVs, respectively. No difference was found regarding comorbidities and imaging parameters between those with and without first pass isolation. LAWT (mean of all 11 regions or separately) had no effect on the procedural outcome (all p>0.05). Out of all assessed parameters, only RSPV diameter was associated with right sided successful PVI on first pass isolation (p=0.04, OR 1.01). Conclusion The use of CLOSE protocol in AF patients resulted in high periprocedural success rate in terms of first pass isolation, independently from the thickness of the LA wall. RSPV diameter could influence the results of first pass isolation. FUNDunding Acknowledgement Type of funding sources: None.

scholarly journals Mechanistic insights into heterogeneous radiofrequency ablation effects at the left atrial posterior wall during pulmonary vein isolation

2019 ◽  
Author(s):  
David R. Tomlinson
Keyword(s):  
Pulmonary Vein ◽  
Pulmonary Vein Isolation ◽  
Left Atrial ◽  
Posterior Wall ◽  
Intermittent Positive Pressure Ventilation ◽  
Positive Pressure ◽  
Rf Ablation ◽  
Overdrive Pacing ◽  
Left Atrial Posterior ◽  
Tissue Motion

AbstractBackgroundIndependent investigations demonstrate greater radiofrequency (RF) ablation effects at left- sided left atrial posterior wall (LAPW) sites.ObjectiveTo investigate mechanisms underlying RF ablation heterogeneity during contact-force (CF) and VISITAG™ Module (Biosense Webster)-guided pulmonary vein isolation (PVI).MethodsConsecutive patients undergoing PVI during atrial overdrive pacing comprised 2 cohorts: intermittent positive pressure ventilation (IPPV, 14-16/min, 6-8ml/kg); high frequency jet ventilation (HFJV, 150/min, Monsoon III, Acutronic). Temperature-controlled (17ml/min, 48°C) RF data was retrospectively assessed at first-annotated (target 15s) LAPW sites: 30W during IPPV; 20W at left-sided sites during HFJV.ResultsTwenty-five and 15 patients underwent PVI during IPPV and HFJV, respectively. During IPPV, left versus right-sided median impedance drop (ImpD) was 13.6Ω versus 9.9Ω (p<0.0001) respectively and mean time to pure R unipolar electrogram (UE) morphology change 4.9s versus 6.7s (p=0.007) respectively. During HFJV, ImpD was greater at left-sided sites (9.7Ω versus 7.4Ω, p=0.21) and time to pure R UE significantly shorter: 4.3s versus 6.1s (p=0.02). Minimum case impedance subtracted from pre-RF baseline impedance (BI) generated site-specific ΔBI. Left-sided sites demonstrated significantly greater ΔBI, correlating strongly with Ln(ImpD) – IPPV r=0.84 (0.65 – 0.93), HFJV r=0.77 (0.35 – 0.93).At right-sided sites, ΔBI and Ln(ImpD) were without correlation during IPPV, but correlation was modest during HFJV (r=0.54, -0.007 – 0.84).ConclusionsΔBI may usefully indicate catheter-tissue contact surface area (SA). Consequently, greater left-sided LAPW RF effect may result from greater contact SA and in-phase catheter-tissue motion; HFJV may reduce right-sided out-of-phase catheter-tissue motion. Modifying RF delivery based on ΔBI may improve PVI safety and efficacy.

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