481 Posterior wall of left atrium and pulmonary veins refractory period is related to atrial fibrillation inducibility in pigs

EP Europace ◽  
2005 ◽  
Vol 7 (Supplement_1) ◽  
pp. 108-108
Author(s):  
I. Fernandez Lozano ◽  
J.M. Escudier ◽  
J. Toquero ◽  
C. Escudero ◽  
V. Mo ivas ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Left Atrium ◽  
Refractory Period ◽  
Pulmonary Veins ◽  
Posterior Wall

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.

Abstract 4655: Retrograde Ethanol Infusion in the Vein of Marshall for Ablation of Atrial Fibrillation: Tissue Ablation, Effects on Regional Vagal Innervation and First Human Experience

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Miguel Valderrábano ◽  
Harvey R Chen ◽  
Jasvinder S Sidhu ◽  
Liyun Rao ◽  
Yuesheng Ling ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Left Atrium ◽  
Coronary Sinus ◽  
Left Atrial ◽  
Vagal Stimulation ◽  
Pulmonary Veins ◽  
Posterior Wall ◽  
Tissue Ablation ◽  
Ethanol Infusion ◽  
Before And After

The vein of Marshall (VOM) is an attractive target during ablation of atrial fibrillation due to its autonomic innervation and its location anterior to the left pulmonary veins and drainage in the coronary sinus. We studied 14 dogs. A coronary sinus venogram showed a VOM in 10, which was successfully cannulated with an angioplasty wire and a 2 mm balloon. In 5 dogs, electroanatomical (Carto) maps of the left atrium were performed at baseline and after ethanol (100%, 4 – 8 cc) was infused in the VOM, which demonstrated the creation of a new crescent-shaped scar in the left atrium, extending from the annular left atrium towards the posterior wall and left pulmonary veins. In 4 dogs, both cervical vagal trunks were isolated in the carotid sheath and cuff stimulation electrodes were attached to them. Effective refractory periods (ERP) were measured in 3 sites of the left atrium, before and after high-frequency bilateral vagal stimulation. The baseline ERP was 113.6±35.0 ms, and decreased to 82.2±25.4 ms (p<0.05) after vagal stimulation. After alcohol infusion in VOM, vagally-mediated ERP decrease was eliminated (from 108±27.2 ms to 95.6 ±16.7ms, p=NS). This elimination of vagal effects was not uniform and was limited in sites in proximity with the VOM (baseline ERP 105±18.7ms vs post vagal 98.±37.6ms, p=NS, as opposed to 106.7±27.1ms vs post vagal 73.3±19.7ms, p<0.05, in sites remote to VOM). We also tested feasibility of VOM alcohol infusion in humans: 2 patients undergoing pulmonary vein antral isolation had successful VOM cannulation: left atrial voltage maps demonstrated new scar involving the infero-posterior left atrial wall extending towards the left pulmonary veins. Retrograde alcohol infusion in the VOM achieves significant left atrial tissue ablation, abolishes local vagal responses and is feasible in humans.

Nonreentrant focal activations in pulmonary veins in canine model of sustained atrial fibrillation

2002 ◽  
Vol 283 (3) ◽  
pp. H1244-H1252 ◽  
Author(s):  
Shengmei Zhou ◽  
Che-Ming Chang ◽  
Tsu-Juey Wu ◽  
Yasushi Miyauchi ◽  
Yuji Okuyama ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Left Atrium ◽  
Right Atrium ◽  
Cycle Length ◽  
Pulmonary Veins ◽  
Posterior Wall ◽  
Canine Model ◽  
Anterior Wall ◽  
High Density ◽  
The Right

Repetitive rapid activities are present in the pulmonary veins (PVs) in dogs with pacing-induced sustained atrial fibrillation (AF). The mechanisms are unclear. We induced sustained (>48 h) AF by rapidly pacing the left atrium (LA) in six dogs. High-density computerized mapping was done in the PVs and atria. Results show repetitive focal activations in all dogs and in 12 of 18 mapped PVs. Activation originated from the middle of the PV and then propagated to the LA and distal PV with conduction blocks. The right atrium (RA) was usually activated by a single large wavefront. Mean AF cycle length in the PVs (left superior, 82 ± 6 ms; left inferior, 83 ± 6 ms; right inferior, 83 ± 4 ms) and LA posterior wall (87 ± 5 ms) were significantly ( P < 0.05) shorter than those in the LA anterior wall (92 ± 4 ms) and RA (107 ± 5 ms). PVs in normal dogs did not have focal activations during induced AF. No reentrant wavefronts were demonstrated in the PVs. We conclude that nonreentrant focal activations are present in the PVs in a canine model of pacing-induced sustained AF.

Neural substrate for atrial fibrillation: implications for targeted parasympathetic blockade in the posterior left atrium

2008 ◽  
Vol 294 (1) ◽  
pp. H134-H144 ◽  
Author(s):  
Rishi Arora ◽  
Joseph S. Ulphani ◽  
Roger Villuendas ◽  
Jason Ng ◽  
Laura Harvey ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Left Atrium ◽  
Refractory Period ◽  
Left Atrial Appendage ◽  
Pulmonary Veins ◽  
Nerve Fibers ◽  
Effective Refractory Period ◽  
Nerve Bundles ◽  
Neural Substrate ◽  
Fibrofatty Tissue

The parasympathetic (P) nervous system is thought to contribute significantly to focal atrial fibrillation (AF). Thus we hypothesized that P nerve fibers [and related muscarinic (M2) receptors] are preferentially located in the posterior left atrium (PLA) and that selective cholinergic blockade in the PLA can be successfully performed to alter vagal AF substrate. The PLA, pulmonary veins (PVs), and left atrial appendage (LAA) from six dogs were immunostained for sympathetic (S) nerves, P nerves, and M2 receptors. Epicardial electrophysiological mapping was performed in seven additional dogs. The PLA was the most richly innervated, with nerve bundles containing P and S fibers (0.9 ± 1, 3.2 ± 2.5, and 0.17 ± 0.3/cm2 in the PV, PLA, and LAA, respectively, P < 0.001); nerve bundles were located in fibrofatty tissue as well as in surrounding myocardium. P fibers predominated over S fibers within bundles (P-to-S ratio = 4.4, 7.2, and 5.8 in PV, PLA, and LAA, respectively). M2 distribution was also most pronounced in the PLA (17.8 ± 8.3, 14.3 ± 7.3, and 14.5 ± 8 M2-stained cells/cm2 in the PLA, PV, and LAA, respectively, P = 0.012). Left cervical vagal stimulation (VS) caused significant effective refractory period shortening in all regions, with easily inducible AF. Topical application of 1% tropicamide to the PLA significantly attenuated VS-induced effective refractory period shortening in the PLA, PV, and LAA and decreased AF inducibility by 92% ( P < 0.001). We conclude that 1) P fibers and M2 receptors are preferentially located in the PLA, suggesting an important role for this region in creation of vagal AF substrate and 2) targeted P blockade in the PLA is feasible and results in attenuation of vagal responses in the entire left atrium and, consequently, a change in AF substrate.

scholarly journals Electrical anatomy of the left atrium during atrial fibrillation

2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
P Adragao ◽  
D Nascimento Matos ◽  
F Costa ◽  
P Galvao Santos ◽  
G Rodrigues ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Sinus Rhythm ◽  
Left Atrium ◽  
Pulmonary Vein ◽  
Refractory Period ◽  
Cycle Length ◽  
Low Voltage ◽  
Pulmonary Veins ◽  
Short Cycle ◽  
Superior Pulmonary Vein

Abstract Introduction Twenty years ago, pulmonary veins (PV) ostia were identified as the left atrium (LA) areas with the shortest refractory period during sinus rhythm. Pulmonary veins isolation (PVI) became standard of care, but clinical results are still suboptimal. Today, a special tool using the Carto® electroanatomical mapping (EAM) allows for AF cycle length mapping (CLM), to identify the areas in the left atria with shortest refractory period, during atrial fibrillation. Using this EAM tool, our study aimed to find the LA areas with the shortest refractory period to better recognize electrical targets for catheter ablation. Methods Retrospective analysis of an unicentric registry of individuals with symptomatic drug-refractory AF who underwent PVI with Carto® EAM. CLM was performed with a high-density mapping Pentaray® catheter before and after PVI and in 4 redo procedures. We assessed areas of short cycle length (SCL) (defined as 120 to 250ms), and their relationships with complex fractionated atrial electrograms (CFAE), and low-voltage zones (from 0.1 to 0.3mV). Results A total of 18 patients (8 men, median age 63 IQR 58–71 years) were included. Most patients presented with persistent AF (n=12, 67%), and 4 patients (22%) had a previous PVI. The mean shortest measured cycle length in AF was 140ms (SD ±27ms). All patients presented areas of SCL located in the PVs or their insertion, 70% in the posterior/roof region adjacent to the left superior pulmonary vein (LSPV) (figure 1) and 60% in the anterior region of the right superior pulmonary vein (RSPV). These two areas remained the fastest even after PVI. The anterior mitral region rarely presented SCL (17%). SCL were related to low-voltage areas in 94% and were adjacent to CFAE. Low-voltage areas and CFAE were more frequent and had a larger LA dispersion than SCL. Conclusion We confirmed in 3D mapping that PVs are the LA zones with shortest refractory period, not only in sinus rhythm but also during AF. The persistence of SCL areas in the border zones of the PVI lines suggest the benefit of a more extensive CLM guided ablation. Larger studies are needed. FUNDunding Acknowledgement Type of funding sources: None. Short cycle length mapping

scholarly journals Electrical anatomy of the left atrium during atrial fibrillation

EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
P Adragao ◽  
D Nascimento Matos ◽  
F Costa ◽  
P Galvao Santos ◽  
G Rodrigues ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Sinus Rhythm ◽  
Left Atrium ◽  
Pulmonary Vein ◽  
Refractory Period ◽  
Cycle Length ◽  
Low Voltage ◽  
Pulmonary Veins ◽  
Density Mapping ◽  
Superior Pulmonary Vein

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Twenty years ago, pulmonary veins (PV) ostia were identified as the left atrium (LA) areas with the shortest refractory period during sinus rhythm. Pulmonary veins isolation (PVI) became standard of care, but clinical results are still suboptimal. Today, a special tool using the Carto® electroanatomical mapping (EAM) allows for AF cycle length mapping (CLM), to identify the areas in the left atria with shortest refractory period, during atrial fibrillation. Using this EAM tool, our study aimed to find the LA areas with the shortest refractory period to better recognize electrical targets for catheter ablation. Methods Retrospective analysis of an unicentric registry of individuals with symptomatic drug-refractory AF who underwent PVI with Carto® EAM. CLM was performed with a high-density mapping Pentaray® catheter before and after PVI and in 4 redo procedures. We assessed areas of short cycle length (SCL) (defined as 120 to 250ms), and their relationships with complex fractionated atrial electrograms (CFAE), and low-voltage zones (from 0.1 to 0.3mV). Results A total of 18 patients (8 men, median age 63 IQR 58-71 years) were included. Most patients presented with persistent AF (n = 12, 67%), and 4 patients (22%) had a previous PVI. The mean shortest measured cycle length in AF was 140ms (SD ±27ms). All patients presented areas of SCL located in the PVs or their insertion, 70% in the posterior/roof region adjacent to the left superior pulmonary vein (LSPV) (figure 1) and 60% in the anterior region of the right superior pulmonary vein (RSPV). These two areas remained the fastest even after PVI. The anterior mitral region rarely presented SCL (17%). SCL were related to low-voltage areas in 94% and were adjacent to CFAE. Low-voltage areas and CFAE were more frequent and had a larger LA dispersion than SCL. Conclusion   We confirmed in 3D mapping that PVs are the LA zones with shortest refractory period, not only in sinus rhythm but also during AF. The persistence of SCL areas in the border zones of the PVI lines suggest the benefit of a more extensive CLM guided ablation. Larger studies are needed. Abstract Figure 1

scholarly journals Persistent Atrial Fibrillation: The Role of Left Atrial Posterior Wall Isolation and Ablation Strategies

2021 ◽  
Vol 10 (14) ◽  
pp. 3129
Author(s):  
Riyaz A. Kaba ◽  
Aziz Momin ◽  
John Camm
Keyword(s):  
Atrial Fibrillation ◽  
Left Atrial ◽  
Pulmonary Veins ◽  
Treatment Strategies ◽  
Persistent Atrial Fibrillation ◽  
Posterior Wall ◽  
Cardiovascular Death ◽  
Good Effect ◽  
Complex Forms

Atrial fibrillation (AF) is a global disease with rapidly rising incidence and prevalence. It is associated with a higher risk of stroke, dementia, cognitive decline, sudden and cardiovascular death, heart failure and impairment in quality of life. The disease is a major burden on the healthcare system. Paroxysmal AF is typically managed with medications or endocardial catheter ablation to good effect. However, a large proportion of patients with AF have persistent or long-standing persistent AF, which are more complex forms of the condition and thus more difficult to treat. This is in part due to the progressive electro-anatomical changes that occur with AF persistence and the spread of arrhythmogenic triggers and substrates outside of the pulmonary veins. The posterior wall of the left atrium is a common site for these changes and has become a target of ablation strategies to treat these more resistant forms of AF. In this review, we discuss the role of the posterior left atrial wall in persistent and long-standing persistent AF, the limitations of current endocardial-focused treatment strategies, and future perspectives on hybrid epicardial–endocardial approaches to posterior wall isolation or ablation.

Abstract 4649: A Radiofrequency HOT Balloon Catheter for Isolating the Posterior Left Atrium Including All the Pulmonary Veins in the Treatment of Atrial Fibrillation: Feasibility and Safety of a New Approach

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Hiroshi Sohara ◽  
Shutaro Satake ◽  
Hiroshi Takeda ◽  
Hideki Ueno ◽  
Toshimichi Oda
Keyword(s):  
Atrial Fibrillation ◽  
Left Atrium ◽  
Phrenic Nerve ◽  
Pulmonary Veins ◽  
Balloon Catheter ◽  
Holter Monitoring ◽  
Phrenic Nerve Palsy ◽  
Total Procedure Time ◽  
Successful Isolation

Atrial fibrillation (AF) is originated from mostly from pulmonary vein (PV) foci or non-PV foci in the posterior left atrium (PLA). The present study was designed to evaluate the usefulness of a radiofrequency HOT balloon catheter (RBC) for isolation of the PLA including all PVs en masse in the patients with AF. In a total of 96 patients (75 men and 21 women; mean age 64±8 years old) with drug-resistant paroxysmal (n=63) and persistent AF(n=33), PLA including all PVs were ablated and isolated using RBC. Dragging the balloon, contiguous lesions at the roof between the superior PVs were first created, then each antrum of all PVs were ablated, and finally, contiguous lesions at the PLA between the both inferior PVs were made, while we performed monitoring esophagus temperature and phrenic nerve pacing. Electro-anatomical bipolar voltage amplitude mapping (CARTO) of the LA-PVs was performed to determine the extent of this electrical isolation after all procedure. Successful isolation of the PLA including all PVs was achieved in all of 96 cases with elimination of all the PLA and PV potentials. The mean total procedure time 133 ± 31 minutes including 32±9 minutes fluoroscopy time. Recurrences of AF were diagnosed by Holter monitoring, mobile electrocardiogram. After first session, eighty- seven (59 paroxysmal, 28 persistent) of 96 patients were free from AF without anti-arrhythmic drugs and the remaining patients could maintain sinus rhythm with anti-arrhythmic drugs except two cases with LA flutter during 11.0±4.1 months follow-up. No major complications such as cerebral embolism, PV stenosis, or phrenic nerve palsy, and LA-esophageal fistula were observed. Complete isolation of the PLA including all PVs using a RBC, is useful for the treatment of both paroxysmal and persistent AF without severe complication.

Sign in / Sign up

Export Citation Format

Share Document