Ablation Of Atrial Tachycardia Research Articles

P Wave Morphology in Inferior Leads May Predict the Higher Recurrence after the Catheter Ablation of Atrial Tachycardia Originating from Para-Hisian Area

Background: Radiofrequency catheter ablation (RFCA) for atrial tachycardia (AT) originating from para-Hisian area is usually difficult and with higher recurrence rate because of a risk in atrio-ventricular block. However, parameters predicting the recurrence of RFCA for para-Hisian AT have not been clarified. Methods: The study subjects consisted of consecutive 8 patients undergoing RFCA for para-Hisian AT from May 2008. Successful RFCA site, total RF energy, the distance from successful site to His bundle and the P wave morphology of AT in inferior leads were evaluated. Results: In acute phase, all ATs were successfully treated with RFCA from the anteroseptal wall of right atrium (RA) in 4 pts, and the non-coronary cusp (NCC) in 4 pts. During 1.6±1.1 years, clinical AT had recurred in three patients consisting of 2 terminated from the NCC and 1 from the RA. There were no significant differences in successful CA site, total delivered energy and the distance from successful site to His bundle between the recurrence and non-recurrence groups. However, biphasic morphology of P wave in inferior leads during AT was significantly more frequent in recurrence group than non-recurrence group (3 pts vs 1 pt, respectively: P<0.05). Conclusion: P wave morphology in inferior leads during AT may be a predictor of successful RFCA for para-Hisian AT.

Safety and Efficacy of Short-Time Compression with Kaolin-Filled Pad after Catheter Ablation

Background: Bleeding and vascular access site complications are an important cause of morbidity after percutaneous femoral procedures. The aim of this study was to evaluate the safety and efficacy of a novel hemostatic device for femoral closure after catheter ablation, in adjunct to short-time compression. Methods: Fourteen consecutive patients (57% male, mean age 64±12 years) undergoing catheter ablation of atrial fibrillation (50%), supraventricular tachycardia (36%), atrial flutter (7%) and premature ventricular contraction (7%) by femoral approach received arterial sheath and multiple venous sheath removal with the QuikClot gauze use. Results: The mean ACT value at hemostasis time was 288 s (range 200–319 s). Hemostasis was achieved in a mean time of 6.0±1.5 min. Only one patient suffered re-bleeding, who was administered aspirin, clopidogrel and warfarin concurrently. Neither major bleeding, nor hematoma occurred. Conclusions: QuikClot gauze could obtain prompt hemostasis. Attention needs to be paid with patients treated with aspirin, clopidogrel and warfarin concurrently.

New Insight of Electrophysiologic Characteristics and Ablation of Focal Atrial Tachycardia Originating from Left Atrial Appendage

Background: Several cases about ATs originating from left atrial appendage (LAA) were reported, but detailed electrophysiologic characteristics of LAA-ATs are not well-known. Objectives: The purpose of this study was to define mechanism and characteristics of the atrial tachycardia (AT) originating from the left atrial appendage (LAA). Methods and Results: Three patients with LAA-AT were included in this study. Electrical pacing and pharmacological evaluation ware performed to test characteristics of LAA-ATs. LAA-gram was performed prior to ablation to confirm anatomical characteristics of LAA. Mechanism of LAA-ATs was automaticity in 2 and lasting at least 10 years and triggered activity in 1. Any drugs were resistant in 2 automaticity ATs, but Na channel-blocker and β-blocker were well affected in triggered AT. 2 foci were located at apex on medial site of LAA, and 1 focus at base. Ring catheter in LAA was helpful to identify the earliest activation site and mapping in the LAA. ATs were eliminated by CA at the earliest activation site where local potential preceded to P wave onset by 60±12 ms. All patients were free from any arrhythmias without any antiarrhythmic drugs follow-up 3±1 years. Conclusion: These data showed that LAA-ATs were uncommon site of origin for focal ATs, but focal intra-LAA ablation was safe and effective to cure these ATs.

Electrophysiological Characteristics of Successful Ablation Sites at Non-Coronary Cusp to Eliminate Adenosine-Sensitive Atrial Tachycardia

Radiofrequency (RF) ablation for adenosine-sensitive atrial tachycardia (AT) has a potential risk of atrioventricular block because it originates from the atrioventricular nodal (AVN) area. The present study aimed to determine whether this AT can be eliminated by RF ablation from the non-coronary cusp (NCC), and, if that’s the case, to elucidate electrophysiological characteristics of successful ablation sites. Method: A total of 5 patients with adenosine-sensitive AT were examined. Results: One to six RF ablations targeting the earliest atrial activation of the AT at the AVN area failed to eliminate the AT. However, only one RF ablation from the NCC successfully cured the AT in all patients without affecting the AVN function. Local atrial activation at the successful ablation sites preceded the earliest atrial activation of the right atrium (RA) 0 msec in 4 patients and 13 msec in 1, and the local electrograms were rather duller and smaller than those of the earliest activation in the RA. During mean follow-up periods of 12 months, no patient had recurrence of the AT. Conclusion: Adenosine-sensitive AT was eliminated by RF ablation from the NCC without affecting the AVN function. The electrogram of the successful ablation site was not very early and sharp compared with those at the earliest atrial activation in the RA. Such anatomical approach of RF ablation was acceptable in adenosine-sensitive AT.

187 Incidental extracardiac findings on cardiac computed tomography performed before radiofrequency ablation of atrial fibrillation

Radiofrequency ablation has became a validated technique to cure symptomatic refractory atrial fibrillation (AF). Cardiac computed tomography (CT) is used to evaluate the left atrial (AT) anatomy in order to improve the ablation technique. The analysis of non-cardiac structures during cardiac CT may identify clinically significant incidental findings (IF). The objective of this study was to determine the prevalence of IF in patients undergoing AF catheter ablation. Between February 2006 and March 2010, patients undergoing a procedure of AF or left atrial tachycardia (LAT) ablation were enrolled and underwent a cardiac CT scan. Extracardiac IF were considered to be present if an abnormality was identified without previous clinical suspicion or known disease. 250 patients (55.2 ± 9.6 years of age, 82.4% men) were enrolled (133 paroxysmal, 43 persistent, 58 permanent AF and 16 LAT). Fifty-eight patients (23.2%) had a total of 76 IF. Patients with IF were significantly older (59.5 ± 8.2 vs 53.8 ± 9.7 years old, p<0.001). No relationship exist between the type of arrhythmia and the existence of IF. The majority of IF were pulmonary (50%). Two lung cancers were discovered. Cardiac CT scan is a useful tool to evaluate LA and pulmonary veins morphology before AF ablation. However, as a considerable prevalence of IF was found in our study, extracardiac structures should be routinely analyzed to detect unknown diseases. Organ Incidental findings n Lungs (n = 38) Emphysema 12 Atelectasis 6 Bronchic syndrome 6 Bronchectasis 5 Fibrosis 2 Pleural effusion 2 Lung cancer 2 Interstitial Pneumonia 1 Pleural calcifications 1 Asbestosis 1 Mediastinum (n = 15) Adenopathy 15 Vasculature (n = 11) Aorta dilation 9 Aorta ulceration 1 Pulmonary arteries anomalies 1 Liver (n = 5) Nodule 3 Cyst 2 Coronary arteries (n = 2) Congenital coronary arteries anomalies 2 Other (n = 5) Hiatal hernia 2 Kidney cyst 1 Pericardial calcifications 1 Thymus relicate 1

Ablation of left atrial tachycardia with cycle length alternans after atrial fibrillation ablation: significance of fractionated electrogram mapping

Atrial tachycardia (AT) with cycle length alternans occurring after atrial fibrillation ablation has not been previously described. Among 66 patients with left AT, stable AT with 2 alternating cycles was registered in 5 cases. Activation mapping of both alternating cycles was performed in all 5 patients. Entrainment and fractionated electrogram mappings were also carried out. Among 10 AT cycles, activation maps suggested underlying mechanism of 5 cycles (50%) in 3 patients. Entrainment pacing was helpful in 2 patients (confirmed mechanism of 2 AT cycles). Catheter ablation successfully terminated AT in all 5 patients: ablation of sites with fractionated potentials in 4 patients and mitral isthmus ablation in 1 patient. Consecutive activation mapping of both AT cycles is feasible for mechanism determination in some patients. The results of our small study suggest that fractionated electrogram-guided ablation might be a reasonable approach for termination of this type of AT.

Catheter Ablation of Focal Atrial Tachycardia from the Aortic Cusp: The Role of Electroanatomic Mapping and Intracardiac Echocardiography

Catheter ablation of periatrioventricular (peri-AV) nodal atrial tachycardias (AT) from the noncoronary aortic cusp (NCC) can be challenging due to the close proximity of the AV node In such cases, intracardiac echocardiography (ICE) together with three-dimensional mapping system can be helpful in guiding the ablation catheter and in assessing the anatomic relationship of the aorta to the surrounding structures. We report two patients with AT originating near the AV node who underwent successful catheter ablation from the NCC. ICE proved useful in positioning the ablation catheter within the aortic cusps. Electroanatomic mapping enabled tagging the earliest activation site and renavigation back.

Identification of a Conduction Gap of the Mitral Isthmus by Using a Novel High‐Density Mapping Catheter

Peri-mitral atrial flutter, which is a type of macroreentrant atrial tachycardia circulating around the mitral annulus, was terminated with the guidance of the high-density mapping catheter. A 72-year-old woman with atrial fibrillation and atrial tachycardia presented with symptoms of congestive heart failure. The recurrent peri-mitral atrial flutter following the initial catheter ablation for atrial tachycardia and atrial fibrillation was terminated by radiofrequency application on the gap that was identified using a novel high-density mapping catheter.

Electrophysiologic Studies and Radiofrequency Catheter Ablation of Ectopic Atrial Tachycardia in Children

Ectopic atrial tachycardia (EAT) often resists medical therapy, making radiofrequency catheter ablation (RFCA) the preferred treatment. This study reviewed the records of 35 patients who underwent electrophysiologic studies (EPS) and 39 RFCA procedures for EAT during a 10-year period. Of the 35 patients, 10 (28%) presented with decreased ventricular function and tachycardia-induced cardiomyopathy (TIC). The EAT originated on the right atrial side in 19 patients (54%) and on the left atrial side in the remaining 16 patients (46%). The right atrial sites included the right atrial appendage (RAA) (n = 9, 25%), the tricuspid annulus (n = 7, 20%), and the crista terminalis (n = 3). The left atrial sites included the left atrial appendage (LAA) (n = 6, 17%), the pulmonary veins (n = 5, 14%), the mitral annulus (n = 3), and the posterior wall of the left atrium (n = 2). The mechanism of all EAT probably is automaticity. All EATs could be abolished using RFCA. Follow-up data were available for all patients 2 to 8 years after RFCA. All 35 patients remained recurrence free, and ventricular function improved for all 10 patients with TIC. The origin of EAT in children differed from its origin in adults. The authors conclude that RFCA is a safe and effective treatment option for children with refractory EAT and should be considered early in the course of their illness.

E0713 Evaluating successful ablation of scar-related atrial tachycardia originating at lateral wall of right atrium with a new method: strategic linear ablation to scar area isolation

BackgroundScar-related Intra-atrial re-entrant tachycardias (IARTs) located at lateral wall of right atrium are common late after cardiac surgery in which right lateral atriotomy was performed, and also occurred in some...

Focal Pseudo-Atrial Fibrillation after Radiofrequency Ablation of Focal Atrial Tachycardia

Focal pseudo‐atrial fibrillation (AF) developed in a 30‐year‐old woman after radiofrequency (RF) ablation of focal atrial tachycardia (AT) originating from the coronary sinus ostium. Programmed atrial stimulation occasionally induced, accelerated or terminated AT, and a spiky prepotential preceded the earliest atrial electrogram at the AT focus. After the first RF application, repetitive bursts of accelerated tachycardia developed, mimicking AF on the surface ECG. An additional RF application where the spiky prepotential was observed, eliminated the focal pseudo‐AF.

E0556 Catheter ablation of atrial tachycardia from the noncoronary cusp of the aortic valve

ObjectiveIn this study, we examine the characteristics of anteroseptal Atrial tachycardias (AT) originating from the Noncoronary Cusp (NCC) of the Aortic Valve, and demonstrate the long-term efficacy and safety of...

How many atrial fibrillation ablation candidates have an underlying supraventricular tachycardia previously unknown? Efficacy of isolated triggering arrhythmia ablation

Supraventricular tachycardia may trigger atrial fibrillation (AF). The aim of the study was to evaluate the prevalence of supraventricular tachycardia (SVT) inducibility in patients referred for AF ablation and to evaluate the effects of SVT ablation on AF recurrences. Two hundred and fifty-seven patients (185 males; mean age: 53.4 ± 14.6 years) referred for AF ablation were studied. In all patients only AF relapses had been documented in the clinical history. Twenty-six patients (10.1%; mean age: 43.4 ± 13.3 years; 17 males) had inducible SVT during electrophysiological study and underwent an ablation targeted only at SVT suppression. Ablation was successful in all 26 patients. The ablative procedures are: 12 slow-pathway ablations for atrioventricular nodal re-entrant tachycardia; 9 concealed accessory pathway ablations for atrioventricular re-entrant tachycardia; and 5 focal ectopic atrial tachycardia ablations. No recurrences of SVT were observed during the follow-up (21 ± 11 months). Two patients (7.7%) showed recurrence of at least one episode of AF. Patients with inducible SVT had less structural heart disease and were younger than those without inducible SVT (interventricular septum thickness: 8.4 ± 1.6 vs. 11.0 ± 1.4 mm, P < 0.01; left atrial diameter: 37.0 ± 3.0 vs. 44.0 ± 2.2 mm, P < 0.01; age: 43.4 ± 13.3 vs. 57.3 ± 11.2 years, P < 0.01). Prevalence of paroxysmal AF was higher in patients with inducible SVT when compared with those with only AF (84.6 vs. 24.6%, P < 0.01). A significant proportion of candidates to AF ablation are inducible for a SVT. SVT ablation showed a preventive effect on AF recurrences. Those patients should be selected for simpler ablation procedures tailored only on the triggering arrhythmia suppression.

Catheter ablation of multiple focal atrial tachycardias originating from the tricuspid annulus using non-contact mapping system

We describe an 81-year-old man with multiple focal atrial tachycardias (ATs) originating from the tricuspid annulus. Non-contact mapping showed 3 incessant ATs, originating from the vicinity of His bundle region, inferior portion of coronary sinus ostium, and coronary sinus ostium, and 2 premature atrial contractions (PACs) originating from the tricuspid annulus in the 5 o'clock position and 6 o'clock position in the left anterior oblique view. Radiofrequency energy application to these 5 sites successfully eliminated the ATs and PACs. The patient has remained free from ATs or any symptoms without medication during the 16-month follow-up period. Non-contact mapping was useful in identifying the multiple AT origins, especially even if the tachycardia origin shifted occasionally or the tachycardia was non-sustained.

Cibenzoline intoxication necessitating implantation of a biventricular assist system in a patient with severe cardiomyopathy

A 46-year-old man was admitted to our hospital in cardiogenic shock. A BVS-5000s biventricular assist system (BVAS) was implanted after establishment of extracorporeal membrane oxygenation. At admission, the patient's serum cibenzoline level was extremely high, 6336 ng/ml. As the cibenzoline level dropped, his cardiac function recovered gradually. The patient was weaned from the right ventricular assist system after pulmonary vein isolation ablation for atrial tachycardia on postoperative day 17, and from left ventricular assist system on day 33. There is the first report of a patient with severe cardiomyopathy induced by cibenzoline intoxication that necessitated implantation of a BVAS. This case illustrates the importance of checking cibenzoline levels regularly in patients receiving long-term therapy with this drug so as to avoid the possibility of severe drug-induced heart failure.

Long‐Term Outcome Following Successful Catheter Ablation of Atrial Tachycardia Originating From the Pulmonary Veins: Absence of Late Atrial Fibrillation

This study aimed to characterize the long-term outcome and incidence of atrial fibrillation (AF) in patients following catheter ablation of focal atrial tachycardia (AT) from the pulmonary veins (PV). Although both AT and AF may originate from ectopic foci within PVs, it is unknown whether PV AT patients subsequently develop AF. Twenty-eight patients with 29 PV ATs (14%) from a consecutive series of 194 patients who underwent RFA for focal AT were included. Patients with concomitant AF prior to the index procedure were excluded. The minimum follow-up duration was 4 years; mean age 38 +/- 18 years with symptoms for 6.5 +/- 10 years, having tried 1.5 +/- 0.9 antiarrhythmic drugs. The distribution of foci was: left superior 12 (41%), right superior 10 (34%), left inferior 5 (17%), and right inferior 2 (7%). The focus was ostial in 93% and 2-4 cm distally within the vein in 7%. Mean tachycardia cycle length was 364 +/- 90 ms. Focal ablation was performed in 25 of 28 patients. There were 6 recurrences with 5 from the original site. Twenty-six patients were available for long-term clinical follow-up. At a mean of 7.2 +/- 2.1 years, 25 of 26 (96%) were free from recurrence off antiarrhythmic drugs. No patients developed AF. Focal ablation for tachycardia originating from the PVs is associated with long-term freedom from both AT and AF. Therefore, although PV AT and PV AF share a common anatomic distribution, PV AT is a distinct clinical entity successfully treated with focal RFA and not associated with AF in the long term.

134 High incidence of acute circumflex artery injury following mitral isthmus ablation

<h3>Background</h3> Mitral isthmus ablation is technically challenging and often requires epicardial ablation in the coronary sinus (CS) for success. The circumflex artery lies in close proximity to the CS and mitral annulus and may potentially be injured during radiofrequency ablation. This study investigates the incidence of coronary artery injury following mitral isthmus ablation. <h3>Methods</h3> This is a single-centre, prospective study of 34 patients who underwent mitral isthmus ablation for atrial fibrillation (AF) and/or atrial tachycardia. Irrigation ablation catheters were used with the following settings: endocardial surface (max power: 40/50 W at the annular end; max temperature: 48°C; flow rate: 20 mls/min); CS (max power: 25/30 W; max temperature: 48°C; flow rate: 20 mls/min). Left coronary angiography was performed pre- and post-ablation. The angiograms were analysed off-line by an independent interventional cardiologist blinded to the ablation procedure. Quantitative Coronary Angiography (QCA) was performed for proximal, mid and distal circumflex artery (Cx), the obtuse marginal branch (OM) and the proximal left anterior descending artery (LAD). <h3>Results</h3> The mean age is 57±11 years, 73% are males, 81% have persistent AF, 35% have structural heart disease and mean left atrial size is 44 mm. Successful mitral isthmus block was achieved in 88% and CS ablation was performed in 68%. The mean ablation times were 686 s (total), 508 s (endocardial) and 170 s (CS). The mean diameters of the vessels are presented in Abstract 134 table 1. Seven out of 34 patients (21%) had mild atheromatous disease at the start. Ten patients (29%) had new angiographic changes following ablation: three had distal occlusion of very small distal Cx; five had stenosis of mid Cx (40–85% stenosis); One had stenosis of mid Cx (60%) and proximal OM (40%); One had stenosis of proximal Cx (25%) and proximal OM (35%). The significant stenoses resolved with intracoronary Glycerin Trinitrate (GTN). Hence, they were likely to represent spasm. Small Cx (&lt;1.5 cm) was associated with a higher risk of injury (50% vs 22%, p&lt;0.05). All significant stenoses were associated with CS ablation. Two cases of small distal Cx occlusion occurred in patients who had endocardial ablation only (40 W). Patients who had Cx artery injury tended to have longer mean ablation times but this did not reach significance (total: 818 s vs 627 s; CS: 240 s vs 139 s; endocardial: 578 s vs 477 s). These patients did not report any clinical symptoms. <h3>Conclusions</h3> Twenty nine per cent of patients had acute angiographic changes following mitral isthmus ablation. In many cases, they represent coronary spasm. These did not result in clinical symptoms. Further studies are needed to investigate the long term outcome of these patients.

Focal Ablation versus Single Vein Isolation for Atrial Tachycardia Originating from a Pulmonary Vein

Rapid, disorganized firing from a pulmonary vein (PV) focus may initiate atrial fibrillation. The natural history of PV atrial tachycardia (AT), resulting in a slower, more organized form of firing, is less clear. Furthermore, the optimal therapeutic approach to a PV AT is poorly defined. This study assessed the characteristics and long-term outcomes of focal ablation versus PV isolation for ATs arising from a single PV. We reviewed 886 consecutive patients who underwent an AT radiofrequency ablation at our institution from January 1997 through August 2008. Twenty-six patients had focal AT with a mean cycle length of 364 +/- 90 ms that arose from within a single PV. Ten patients underwent focal ablation of their AT and 16 patients underwent PV isolation of the culprit vein. All procedures were acutely successful. The average follow-up was 25 months (range 2-90 months). There were three recurrences of AT in patients who underwent a focal ablation. There were no recurrences in patients who underwent targeted PV isolation (P = 0.046). No patients developed atrial fibrillation or AT from another focus during the follow-up period. PV AT can be successfully treated with single vein isolation or focal ablation with a low risk of recurrence or the development of atrial fibrillation. PV isolation may be the preferred approach when the AT focus arises from a site distal to the ostium where targeted ablation could result in phrenic nerve injury or occlusion of a pulmonary venous branch.

Ablation of atrial tachycardia originating from the noncoronary sinus: case report and literature review

This report describes a patient with atrial tachycardia who underwent radiofrequency catheter ablation. Two applications of radiofrequency energy were received at different sites within 1 week. Initially, right atrium mapping indicated that the earliest activation site was located at the His-bundle region (HBR). However, the first application of radiofrequency near HBR appeared to be ineffective. Moreover, a degree III atrioventricular block and inferior ST-segment elevation was temporally observed during the therapy, which recovered after drug treatment. As later aortic sinus mapping showed that the activation site located at the noncoronary sinus (NCS) preceded the one at HBR, and this activation terminated at atrial tachycardia, a second application of radiofrequency was performed at NCS without any complications. In addition, a literature review of the clinical features of atrial tachycardia at the NCS is also summarized in the present report.

Electrophysiologic characteristics and radiofrequency ablation of focal atrial tachycardia arising from non-coronary sinuses of Valsalva in the aorta

Focal atrial tachycardia (AT) arising from non-coronary cusp (NCC) is very rare, and the experience in catheter ablation of this kind of tachycardia remains limited. This study describes the electrophysiologic characteristics and radiofrequency ablation of AT arising from NCC. The study population consisted of five consecutive patients (three females and two males; age 37-68 years) with AT arising from NCC. The morphology of P waves was described as positive, negative, isoelectric, or biphasic (positive-negative or negative-positive). The atrial mapping was performed during tachycardia to define the earliest atrial activation site. Mean tachycardia cycle length of AT in five patients was 363 +/- 44 ms. P-wave morphology was predominantly upright or biphasic in lead II, III, and aVF, inverted in aVR. Positive P-wave morphology was seen in lead aVL in all five patients. The precordial leads were negative-positive in V(1) and V(2), negative-positive or positive in lead V(3)-V(5), and positive in lead V(6). All the five patients underwent successful radiofrequency ablation within NCC. During a follow up of > 3 months, no patient presented with a recurrence. This study demonstrated that mapping and ablation of focal AT arising from NCC is safe and effective. When earliest activation was recorded in the proximal electrode of the His-bundle catheter, but radiofrequency ablation in this region cannot successfully eliminated the tachycardia, the AT should be considered to arise from NCC especially when P-wave morphology was initially negative with a late positive component in right precordial leads, upright or biphasic in inferior leads.