Clinical significance of early atrial arrhythmia type and timing after single ring isolation of the pulmonary veins.

AIMS: Early atrial arrhythmia following atrial fibrillation (AF) ablation is associated with higher recurrence rates. Few studies explore the impact of early AF (EAF) and atrial tachycardia (EAT) on long-term outcomes. Furthermore, EAF/EAT have not been characterized after wide pulmonary vein isolation. We aimed to characterize EAF and EAT and its impact on late AF (LAF) and AT (LAT) after single ring isolation (SRI). METHODS AND RESULTS: We recruited 119 (females 21, age 58 ± 10 years) consecutive patients with AF (paroxysmal 76, persistent 43) undergoing SRI. Early atrial fibrillation/ early atrial tachycardia was defined as AF/AT within 3 months post-procedure (blanking period). Patients were followed for median 2.8[2.2-4] years. Early atrial fibrillation occurred in 28% (n = 33) and EAT in 25% (n = 30). At follow-up, 25% (n = 30) had LAF and 28% (n = 33) had LAT. Patients with EAF and EAT had higher rates of LAF (48 vs. 16%, P<0.0001) and LAT (60 vs. 16%, P < 0.0001), respectively. Independent predictors of LAF were EAF (3.53(1.72-7.29) P = 0.001); and of LAT were EAT (5.62(2.88-10.95) P < 0.0001) and procedure time (1.38/ h(1.07-1.78) P = 0.04). Importantly, EAF did not predict LAT and EAT did not predict LAF. Early atrial fibrillation late in the blanking period was associated with higher rates of LAF (73% for month 3 vs. 25% for Months 1-2, P = 0.004). However, EAT timing did not predict LAT. CONCLUSION: Early atrial fibrillation and EAT are predictive of LAF and LAT, respectively. Early atrial fibrillation late in the blanking period has greater predictive significance for LAF. This timing is not relevant for LAT. Early arrhythmia type and timing have important prognostic significance following SRI. CLINICAL TRIAL REGISTRATION: http://www.anzctr.org.au;ACTRN12606000467538.

An unusual atrial tachycardia in a patient with Friedreich ataxia.

We present the unusual association of an atrial tachycardia with Friedreich ataxia. The arrhythmia was initially suspected to be focal in origin; however, use of a three-dimensional mapping system demonstrated that the tachycardia was macro-reentrant. This was subsequently treated successfully by linear ablation.

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

INTRODUCTION: Atrial tachycardia (AT) with cycle length alternans occurring after atrial fibrillation ablation has not been previously described. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Organized left atrial tachyarrhythmia during stepwise linear ablation for atrial fibrillation.

INTRODUCTION: This study attempted to delineate the mechanism of organized left atrial tachyarrhythmia (AT) during stepwise linear ablation for atrial fibrillation (AF) using noncontact mapping. METHODS AND RESULTS: Eighty patients in whom organized ATs developed or induced during stepwise linear ablation for AF were enrolled. Left atrial (LA) activation during ATs was mapped using noncontact mapping. Radiofrequency (RF) energy was delivered to the earliest activation site or narrowest part of the reentrant circuit of ATs. A total of 146 ATs were mapped. Four ATs were characterized as a focal mechanism (cycle length (CL): 225 +/- 49 ms). A macroreentrant mechanism was confirmed in the remaining 142 ATs. LA activation time accounted for 100% of CL (205 +/- 37 ms). All 142 ATs used the conduction gaps in the basic figure-7 lesion line. There were three types of circuits classified based on the gap location. Type I (n = 68) used gaps at the ridge between left atrial appendage (LAA) and left superior pulmonary vein (LSPV). Type II (n = 50) used gaps on the LA roof. Type III (n = 24) passed through gaps in the mitral isthmus. Ablation at these gaps eliminated 130 ATs. During the follow-up period of 16.2 +/- 6.7 months, 82.5% of the 80 patients were in sinus rhythm. CONCLUSION: The majority of left ATs developed during stepwise linear ablation for AF are macroreentrant through conduction gaps in the figure-7 lesion line, especially at the LAA-LSPV ridge. Noncontact activation mapping can identify these gaps accurately and quickly to target effective catheter ablation.

A deductive mapping strategy for atrial tachycardia following atrial fibrillation ablation: importance of localized reentry.

BACKGROUND: Atrial tachycardia (AT) occurring following catheter ablation of persistent atrial fibrillation (AF) may be challenging to map and ablate because their mechanism and location is unpredictable and may be multiple in an individual patient. METHODS AND RESULTS: A prospective cohort of 128 consecutive patients presenting 246 AT in the context of prior AF ablation was investigated. Using activation and entrainment mapping and applying the consensus definition of AT, we evaluated a deductive diagnostic approach based on up to three steps: (1) cycle length regularity, (2) search for macroreentry (i.e., involving >2 separate atrial segments), and (3) if macroreentry excluded, search for focal origin giving a centrifugal activation of the atria. A total of 238/246 (97%) sustained AT (mean cycle length [CL] 284 +/- 87 ms) were successfully mapped (single AT, 51 pts; multiple AT, 77 pts) with a diagnostic time of 10 +/- 8 min per tachycardia. AT were macroreentrant in 109 (46%) and focal in 129 (54%). Of the latter, only 34 focal AT originated from a discrete point site fulfilling the consensus criteria, while a distinct mechanism, localized reentry (AT that was neither macro reentry nor focal), was identified in 95. Localized reentry was defined by (1) electrograms covering >or=75% of the cycle length of AT within an area covering a single or 2 contiguous segments, (2) postpacing interval (PPI) < 30 ms at the site, (3) an identifiable zone of slow conduction, and (4) centrifugal activation of the atrium from the area. CONCLUSIONS: This prospective study demonstrates the feasibility of rapid and accurate identification of all types of postablation AT in a large cohort of patients and describes the dominant role of localized reentry as a novel mechanism of AT.

Ablation of atrial tachycardias after correction of complex congenital heart diseases: utility of intracardiac echocardiography.

AIMS: Our goal was to analyse the utility of intracardiac echocardiography (ICE) for navigation and ablation of atrial tachycardias (ATs) after surgical correction of congenital heart disease (CHD). METHODS AND RESULTS: Catheter ablation of ATs was performed in seven patients (one woman, mean age 21 +/- 6 years) after correction of complex CHD: d-transposition of the great arteries (Mustard procedure in two patients, Senning procedure in two patients) and univentricular circulation (total cavopulmonary connection in two patients, atriopulmonary connection in one patient). The ablation was guided by a combination of electroanatomical mapping (CARTO, Biosense-Webster) and ICE (Acuson, Siemens). Intracardiac echocardiography was used during mapping to identify relevant anatomical structures and monitor tissue contact and for guidance of atrial baffle puncture. Biatrial mapping was necessary in six of seven patients and atrial baffle puncture in three. The clinical AT was abolished in all patients. No complications were noted. During follow-up of 23 +/- 13 months, two patients (28%) had arrhythmia recurrence. One patient developed atrial fibrillation, and recurrent AT in the other patient was controlled by re-ablation. CONCLUSION: Despite complicated cardiac anatomy, catheter ablation of AT after complex CHD can be performed safely and with a high success rate. Intracardiac echocardiography facilitates mapping, identification of relevant cardiac structures, and could be used for safe guidance of transbaffle puncture.

Atrial tachycardias encountered in the context of catheter ablation for atrial fibrillation part ii: mapping and ablation.

Over the past decade, there has been an exponential increase in the number of catheter ablation procedures performed for atrial fibrillation (AF). While for paroxysmal AF, proximal pulmonary vein isolation is sufficient in the majority of cases, ablation of persistent and longstanding AF requires an extensive surgical-like procedure. This approach is correlated with a high rate of AF termination; however, this is achieved at the cost of at least one atrial tachycardia (AT) during the index procedure or during the patient's follow-up in the vast majority of cases. As these ATs are often multiple, complex, and frequently more symptomatic than AF, they constitute the last and frequently the most difficult step in ablation for patients with persistent AF. This review concentrates on the practical approaches to the treatment of AT in the context of AF ablation and provides an algorithm that aims at facilitating mapping and ablation strategies using conventional electrophysiological tools.

Successful ablation of atrial tachycardia in the right coronary cusp of the aortic valve in a patient with atrial fibrillation: what is the substrate?

Atrial tachycardias have been successfully ablated from the noncoronary cusp of the aortic valve. The anatomical substrate responsible for the arrhythmia in these patients is unknown. We report a case of intracardiac ultrasound confirmed ablation in the right coronary cusp of the aortic valve. Pacing maneuvers performed in this case, along with the regional anatomy of the right coronary cusp, strongly suggest that the ablated substrate is muscular extensions above the aortic valve. Ablation in the right coronary cusp eliminated tachycardia without valve damage or AV conduction abnormality.

Dual independent atrial tachycardias after ablation of chronic atrial fibrillation.

We report the case of a 71-year-old man with two atrial tachycardias evolving simultaneously and independently in two dissociated regions after extensive ablation for chronic atrial fibrillation. One tachycardia was a focal tachycardia originating from the right inferior pulmonary vein and activating the posterior left atrium with a 2:1 conduction block, while the other tachycardia was an atrial flutter circulating around the tricuspid annulus, activating the right atrium and the anterior wall of the left atrium. These two atrial tachycardias were successfully ablated prior to restoration of sinus rhythm.

["Benign" atrial arrhythmias exacerbated by physical activity as a cause of cardiomyopathy]. / "Lagodne" arytmie przedsionkowe nasilane wysilkiem przyczyna kardiomiopatii.

We describe a 39-year-old man with premature atrial contractions at rest, in whom tachycardia was exacerbated by exercise into long-lasting atrial tachycardia of 150 beats/min with changeable grade of AV conduction. The feeling of irregular heart beating was the only symptom of arrhythmia and was well tolerated for many years. However, the signs of tachycardia-mediated cardiomyopathy with heart failure developed over several years. Successful RF ablation of focal atrial tachycardia using the CARTO system was performed. After 5 months of follow-up the patient is free from arrhythmia with a significant improvement of the HF.

[Arrhythmia in adults with congenital heart defects : Atrial tachycardia]. / Arrhythmien bei Erwachsenen mit angeborenen Herzfehlern : Atriale Tachykardien.

Atrial arrhythmias are frequently encountered in patients with congenital heart disease (CHD) with or without corrective surgery and respond to pharmacological therapies with only limited success. This review describes the technologies currently available for performing successful ablation procedures in this very complex patient cohort. In addition to an understanding of the underlying anatomy, which can be supplemented by 3D imaging with the aid of magnetic resonance imaging (MRI) or computed tomography (CT), the choice between the different 3D mapping systems (sequential versus simultaneous) is presented. Finally, conventional manual navigation is compared with magnetic navigation and then discussed with regard to the respective arrhythmias encountered with the different forms of CHD.

Electroanatomical mapping and radiofrequency catheter ablation of atrial tachycardia originating from the donor heart after orthotopic heart transplantation in a child.

A 15-year-old boy who had been given an orthotopic heart transplant 12 years earlier underwent radiofrequency ablation after 14 months of tachycardia. At the time of the procedure, the patient presented moderate signs of heart failure and tachycardia-induced cardiomyopathy. During electroanatomical mapping we identified a focal atrial tachycardia with origin in the donor right atrium and bi-directional atrio-atrial conduction. After successful focal ablation the patient had two alternating atrial activation patterns, representing the recipient and the donor heart sinus rhythm. Two months after the ablation heart failure symptoms were in regress, and the patient was still in sinus rhythm.

[Ablation of postoperative "incisional" reentrant atrial tachycardia and flutter in children using the CARTO system].

OBJECTIVE: In children with congenital heart diseases who have undergone surgical interventions, postoperative arrhythmias frequently complicate the clinical course. "Incisional" atrial tachycardia or flutter is one of the most common forms of postoperative arrhythmias in these patients and can lead to significant morbidity and even mortality. The aim of this study was to investigate how to use antiarrhythmic drugs and the CARTO system to treat these cases. METHODS: There were 12 patients with "incisional" atrial tachycardia or flutter complicating surgery for congenital heart diseases in this study (3 patients with correction of tetrology of Fallot, 3 with atrial septal defect repair, 2 with ventricular septal defect repair, 1 with switch, 1 with repair of Ebstein's anomaly, 1 with total anomalous pulmonary venous drainage, and 1 with atrial septal closure with the Amplatzer septal occlusion). Patients whose body weight was less than 10 kg or those who did not wish to accept ablation were treated with antiarrhythmic drugs, including digitoxin, propranolol, metoprolol and cordarone. CARTO system was used to map 6 patients whose body weight was more than 10 kg and who agreed with accepting ablation for atrial tachycardia and flutter. Radio-frequency ablation was performed in these 6 cases including two cases of "incisional" atrial tachycardia and 4 of atrial flutter. RESULTS: (1) The antiarrhythmic drug was successful in 6 patients with "incisional" atrial tachycardia. (2) Six patients including 2 children with "incisional" atrial tachycardia and 4 children with atrial flutter were successfully ablated. But one case of "incisional" atrial tachycardia relapsed after 3 months of ablation. This case, however, was successfully ablated again later. No further relapse was observed during the 2 - 24 months of follow-up. CONCLUSION: Ablation of "incisional" atrial tachycardia and flutter is the first choice to treat the patients whose body weight is more than 10 kg and those who agree with accepting ablation by CARTO system. Drug therapy of "incisional" atrial tachycardia and flutter is palliative and it is the only selection to treat the patients whose body weight is less than 10 kg or those who do not wish to accept ablation procedure.

[Reversible thyrotoxic cardiomyopathy--report of three cases]. / Odwracalna kardiomiopatia w przebiegu tyreotoksykozy--opis trzech przypadków.

Three patients with thyrotoxicosis, atrial tachyarrhythmia and congestive heart failure despite successful treatment of hyperthyroidism revealed atrial fibrillation/flagellation and left ventricular systolic dysfunction. Congestive heart failure resolved and left ventricular systolic function normalized only after successful cardioversion to sinus rhythm. In some patients treated for hyperthyroidism, achievement of euthyroid state is not by itself sufficient to reverse left ventricular failure. Improvement after successful reversion of atrial tachyarrhythmia suggest its essential role in pathogenesis of thyrotoxic cardiomyopathy.

Necessity for biatrial ablation to achieve bidirectional cavotricuspid isthmus conduction block in a patient following senning operation.

We report the case of a 28-year-old male patient with a 17-year history of recurrent symptomatic atrial tachyarrhythmia following Senning operation for transposition of the great arteries. Biatrial electroanatomic mapping and entrainment mapping revealed counterclockwise peri-tricuspid annulus reentry in which cavotricuspid isthmus tissue in both systemic and pulmonary venous atria was involved. Linear ablation of the cavotricuspid isthmus in the pulmonary venous atrium terminated the tachycardia but did not block the isthmus conduction, and the tachycardia was reinduced. Bidirectional isthmus conduction block could be achieved only after additional linear ablation targeting the cavotricuspid isthmus tissue in the systemic venous atrium. We conclude that biatrial ablation may be necessary in order to achieve bidirectional isthmus block and prevent tachycardia recurrence in some patients following Senning or Mustard operation.