Fibrillation Induced by High-Rate Pacing From Either the Pulmonary Veins, the Right Atrium or the Coronary Sinus Reveals Properties of Spontaneously Occurring Paroxysmal Atrial Fibrillation in Humans

Heart Rhythm ◽  
2011 ◽  
Vol 8 (11) ◽  
pp. 1826
Author(s):  
F. Atienza ◽  
D. Calvo ◽  
J. Jalife ◽  
L. Bravo ◽  
J. Almendral ◽  
...  
2001 ◽  
Vol 65 (10) ◽  
pp. 893-896 ◽  
Author(s):  
Junichi Sekiya ◽  
Yoshio Ohnishi ◽  
Tomoo Inoue ◽  
Mitsuhiro Yokoyama

2002 ◽  
Vol 283 (3) ◽  
pp. H1244-H1252 ◽  
Author(s):  
Shengmei Zhou ◽  
Che-Ming Chang ◽  
Tsu-Juey Wu ◽  
Yasushi Miyauchi ◽  
Yuji Okuyama ◽  
...  

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.


Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Ramtin Anousheh ◽  
Navinder Sawhney ◽  
Charles Tate ◽  
Michael Panutich ◽  
Wayne Whitwam ◽  
...  

Background: Incomplete or unidirectional mitral isthmus block (MIB) during left atrial linear ablation (LALA) for atrial fibrillation (AF) may be proarrhythmic, and is the most common target for repeat ablation in patients with atypical atrial flutter (AAFL) after LALA. Objective: To determine if achieving bidirectional MIB during LALA will reduce occurrence post-ablation AAFL and/or recurrence of AF. Methods and Results: Fifty-six consecutive patients (pts), 49 males and 7 females, mean age 59±8 years, who underwent LALA for symptomatic, persistent (61%) or paroxysmal (39%) AF were evaluated. Thirty-four pts had been previously ablated, none had MIB from the first ablation. All pts underwent LALA including two encircling lesions around the right and left pulmonary veins, a line at the roof of the left atrium between the two circles, and a line from the lateral mitral valve annulus (MVA) to the left circle with adjunctive coronary sinus ablation as needed to achieve MIB. Thirty pts had an additional line from the septal MVA to the right circle. Bi-directional MIB was documented by pacing from the left atrial appendage and proximal coronary sinus. Bi-directional MIB was achieved in 38 pts (68%), with ablation in the coronary sinus required in 87.5% of pts. Thirty-seven pts underwent LALA with a standard 8 mm tip (Blazer™ or Navistar™) catheter and 19 pts with saline-irrigated catheters (ThermoCool™, Chili™). Patients were followed for 6±2 months. AAFL occurred in 15 pts (27%), and 17 pts (30%) had recurrence of AF. In pts with AAFL, 8 had documented bi-directional MIB during ablation and 7 did not. The odds of AAFL was 7.6 times higher in pts without MIB compared those with MIB (p=0.02); adjusting for age, gender, diagnosis, type of catheter, coronary sinus ablation and history of previous ablation. This study did not show similar association between recurrence of AF and MIB (p=0.5). Conclusions: Achieving bi-directional MIB will reduce incidence of post-ablation AAFL significantly. Recurrence of AF is not reduced by achieving bi-directional MIB.


2012 ◽  
Vol 1 ◽  
pp. 34 ◽  
Author(s):  
Sanjiv M Narayan ◽  
David E Krummen ◽  
◽  

Therapy for atrial fibrillation (AF) remains suboptimal, in large part because its mechanisms are unclear. While pulmonary vein ectopy may trigger AF, it remains uncertain how AF, once triggered, is actually sustained. Recent discoveries show that human AF is maintained by a small number of rotors or focal sources. AF sources are widely distributed in patient-specific locations, often remote from pulmonary veins and in the right atrium and stable for prolonged periods of time. In a multicentre experience, brief targeted ablation at sources (focal impulse and rotor modulation [FIRM]) terminated AF predominantly to sinus rhythm prior to pulmonary vein isolation and eliminated AF on rigorous followup. This review summarises the evidence for stable rotors and focal sources of human AF and their clinical role as ablation targets to eliminate paroxysmal, persistent and long-standing persistent AF.


EP Europace ◽  
2001 ◽  
Vol 3 (1) ◽  
pp. 4-9 ◽  
Author(s):  
A. Andraghetti ◽  
M. Scalese

Abstract Aim To present some safety and efficacy issues of low-energy internal cardioversion of chronic atrial fibrillation from 500 consecutive procedures performed with two different techniques, using either two single-coil catheters, or a single twin-coil catheter. Methods and Results Low-energy internal cardioversion was carried out in 368 patients by means of two defibrillation catheters: the former was positioned in the right atrium and the latter either in the left pulmonary artery (212 patients), or in the distal coronary sinus (156 patients). In the remaining 132 patients, a single twin-coil catheter was positioned with the distal coil either in the pulmonary artery (75 patients) or in the coronary sinus (57 patients), while the proximal coil was in the right atrium. The external defibrillator delivered truncated biphasic shocks (6/6 ms, tilt 50%), with a voltage of 10–400 V. In 283 patients (57%) external cardioversion had been unsuccessfully tried before low-energy internal cardioversion. After a total of 1118 shocks, the overall success rate was 92·2% (91·3% with two catheters and 94·7% with the single catheter); the success rate was 93·4 and 91·3% with the coronary sinus and the pulmonary artery approach, respectively. The mean energy used was 6·5±3·4 J (voltage: 320±45 V); no difference was found between the twin catheter (6·3±3·1 J) and the single catheter approach (6·9±3·7 J), while the coronary sinus configuration required a significantly lower energy than the pulmonary artery configuration (5·6±2·9 vs 7·2±3·8 J, P<0·05). The duration of the current atrial fibrillation episode was the only clinical characteristic statistically different between the 461 successfully cardioverted patients and the 39 failures (295 vs 727 days, P<0·01). No complication was recorded during or after the delivery of the therapy; no procedure had to be terminated because of patient's intolerance. Conclusions Low-energy internal cardioversion is a safe and effective procedure for converting chronic atrial fibrillation, confirmed by this large multicentre experience. The newly available twin-coil catheter seems to achieve a slightly better success rate compared with the traditional two-catheter technique, and is associated with the same safety profile.


2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
I Marco Clement ◽  
R Eiros ◽  
R Dalmau ◽  
T Lopez ◽  
G Guzman ◽  
...  

Abstract Introduction The diagnosis of sinus venosus atrial septal defect (SVASD) is complex and requires special imaging. Surgery is the conventional treatment; however, transcatheter repair may become an attractive option. Case report A 60 year-old woman was admitted to the cardiology department with several episodes of paroxysmal atrial flutter, atrial fibrillation and atrioventricular nodal reentrant tachycardia. She reported a 10-year history of occasional palpitations which had not been studied. A transthoracic echocardiography revealed severe right ventricle dilatation and moderate dysfunction. Right volume overload appeared to be secondary to a superior SVASD with partial anomalous pulmonary venous drainage. A transesophageal echocardiography confirmed the diagnosis revealing a large SVASD of 16x12 mm (Figure A) with left-right shunt (Qp/Qs 2,2) and two right pulmonary veins draining into the right superior vena cava. Additionally, it demonstrated coronary sinus dilatation secondary to persistent left superior vena cava. CMR and cardiac CT showed right superior and middle pulmonary veins draining into the right superior vena cava 18 mm above the septal defect (Figures B and C). After discussion in clinical session, a percutaneous approach was planned to correct the septal defect and anomalous pulmonary drainage. For this purpose, anatomical data obtained from CMR and CT was needed to plan the procedure. During the intervention two stents graft were deployed in the right superior vena cava. The distal stent was flared at the septal defect level so as to occlude it while redirecting the anomalous pulmonary venous flow to the left atrium (Figure D). Control CT confirmed the complete occlusion of the SVASD without residual communication from pulmonary veins to the right superior vena cava or the right atrium (Figure E). Anomalous right superior and middle pulmonary veins drained into the left atrium below the stents. Transthoracic echocardiographies showed progressive reduction of right atrium and ventricle dilatation. The patient also underwent successful ablation of atrial flutter and intranodal tachycardia. She is currently asymptomatic, without dyspnea or arrhythmic recurrences. Conclusions In this case, multimodality imaging played a key role in every stage of the clinical process. First, it provided the diagnosis and enabled an accurate understanding of the patient’s anatomy, particularly of the anomalous pulmonary venous connections. Secondly, it allowed a transcatheter approach by supplying essential information to guide the procedure. Finally, it assessed the effectiveness of the intervention and the improvement in cardiac hemodynamics during follow-up. Abstract P649 Figure.


EP Europace ◽  
2020 ◽  
Author(s):  
Michelle Lycke ◽  
Maria Kyriakopoulou ◽  
Milad El Haddad ◽  
Jean-Yves Wielandts ◽  
Gabriela Hilfiker ◽  
...  

Abstract Aims Catheter ablation of paroxysmal atrial fibrillation (AF) reduces AF recurrence, AF burden, and improves quality of life. Data on clinical and procedural predictors of arrhythmia recurrence are scarce and are flawed by the high rate of pulmonary vein reconnection evidenced during repeat procedures after pulmonary vein isolation (PVI). In this study, we identified clinical and procedural predictors for AF recurrence 1 year after CLOSE-guided PVI, as this strategy has been associated with an increased PVI durability. Methods and results Patients with paroxysmal AF, who received CLOSE-guided PVI and who participated in a prospective trial in our centre, were included in this study. Uni- and multivariate models were plotted to find clinical and procedural predictors for AF recurrence within 1 year. Three hundred twenty-five patients with a mean age of 63 years (CHA2DS2VASc 1 [1–3], left atrium diameter 41 ± 6 mm) were included. About 60.9% were male individuals. After 1 year, AF recurrence occurred in 10.5% of patients. In a binary logistic regression analysis, the diagnosis-to-ablation time (DAT) was found to be the strongest predictor of AF recurrence (P = 0.011). Diagnosis-to-ablation time ≥1 year was associated with a nearly two-fold increased risk for developing AF recurrence. Conclusion The DAT is the most important predictor of arrhythmia recurrence in low-risk patients treated with durable pulmonary vein isolation for paroxysmal AF. Whether reducing the DAT could improve long-term outcomes should be investigated in another trial.


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