[Show abstract][Hide abstract] ABSTRACT: Background
Natural history of atrial fibrillation (AF) is characterized by gradual increase in duration and frequency of relapses until a definitive shift to permanent AF. Heart disease and comorbidities modulate AF progression, however, to date, the influence of catheter ablation on AF evolution has rarely been investigated.
Our aim is to identify long-term predictors of AF progression in a large cohort of patients undergoing transcatheter AF ablation (AFTCA).
889 patients (mean age 57±11 years, 53.3% paroxysmal, 40.5% persistent and 6.2% long-standing AF) underwent AFTCA. All patients received pulmonary veins isolation while linear lesions and complex fractionated atrial electrograms ablation were reserved for patients with persistent/long-standing AF and/or in confirmed structural heart disease.
After a median follow up of 64 (41–84) months, AF progression despite AFTCA occurred in 57 (6.4%) cases. However, AF progression was much more pronounced in patients afflicted by persistent (10%) and long-standing persistent AF (14,6%) compared to patients afflicted by paroxysmal AF (2,7%, p<0.001). Furtheremore, AF progression was more frequently reported in patients presenting with underlying comorbidities/cardiomyopathies (9.1%)compared to those presenting with lone AF (29.9%, p<0.001). At multivariate analysis, comorbidities/cardiomyopathies and baseline persistent/long-standing AF proved as independent predictors of progression (OR 11.3, CI 95% 2.6-48.0, p<0.001 and OR 1.6, CI 95% 1.2-2.1, p<0.001 respectively).
The presence of comorbidities/cardiomyopathies and persistent/long-standing AF seem to predict AF progression in patients undergoing AFTCA. Performing AFCTA in the paroxysmal phase of the arrhythmia may reduce progression of AF to its permanent form.
Full-text · Article · May 2014 · Heart rhythm: the official journal of the Heart Rhythm Society
[Show abstract][Hide abstract] ABSTRACT: The previous literature has suggested that the iatrogenic atrial septal defects (IASDs) may follow left atrial (LA) access by transseptal (TS) puncture, especially in the case of a single TS for more than one catheter. The aim of the present study is to describe the prevalence of patent foramen ovale (PFO) and IASDs in a cohort of atrial fibrillation (AF) patients undergoing redo catheter ablation (CA) procedures in a high-volume centre accessing LA by a standardized single TS puncture.METHODS AND RESULTS: Patients (n = 197) who underwent at least one redo AFCA, between 2004 and 2012, were retrospectively enroled. Transoesophageal echocardiography was performed before each procedure during which LA was accessed via a PFO, if present, or by single TS for both the mapping and ablation catheters. At baseline, PFO was detected in 43 (21.8%) patients. Clinical and echocardiographic parameters recorded did not differ within patients presenting with or without PFO. Left atrium was accessed via PFO in 39 (90.7% of those with PFO) patients during the first procedure. New-onset IASD occurred in 11 (5.6%) patients following the first procedure and in 1 (2.2%) patient following the second procedure. The clinical and echocardiographic parameters did not differ within the patients irrespective of whether IASD was reported or not. No TS-related complications occurred.CONCLUSION: In the present cohort, LA access by PFO or single TS for both the mapping and ablation catheters lead to a small risk of asymptomatic IASD, not increased by redo procedures, confirming that it represents a safe approach. No clinical and/or echocardiographic parameters seemed to predict IASD occurrence.
[Show abstract][Hide abstract] ABSTRACT: Net clinical benefit of long-term oral anticoagulation therapy (OAT) continuation after successful atrial fibrillation (AF) ablation is still controversial. To evaluate long-term thromboembolic (TE) and haemorrhagic events incidence according to OAT strategy used after AF transcatheter ablation.METHODS AND RESULTS: Three months after AF ablation, OAT was discontinued in patients with CHADS2 ≤ 1 if no recurrences were documented, while OAT was maintained in patients with CHADS2 ≥ 2 regardless of AF recurrences. CHA2DS2VASc and HAS-BLED scores have been retrospectively evaluated. Seven hundred and sixty-six patients were followed for a median of 60.5 months. Six (6/267 = 2.2%) and five (5/499 = 1%) TE events occurred in the ON and the OFF-OAT patients, respectively (P = 0.145), all in concomitance with the AF recurrence. CHADS2 and CHA2DS2VASc ≥ 2 were associated with high TE incidence (P = 0.047 and P = 0.020). Among patients with a CHADS2 score of 0 or 1, a CHA2DS2VASc score ≥ 2 was predictive of TE events (P = 0.014). Overall, the incidence of the TE events in patients with CHA2DS2VASc ≥ 2 was 0.6 per 100 patient-years whereas seven haemorrhagic events occurred, all of them in the ON-OAT patients (7/267 = 2.6%).CONCLUSION: Patients with AF undergoing transcatheter ablation have a lower incidence of TE events as compared with the general AF population, regardless of OAT maintenance. The unpredictable risk of AF recurrence, mandate the routine use of the CHADS2, CHA2DS2VASc, and HAS-BLED scores to guide clinical decision regarding OAT management in this peculiar setting of patients. The potential protective role of rhythm control strategy in the TE events needs to be confirmed by future large randomized trials.
[Show abstract][Hide abstract] ABSTRACT: Purpose: Guidelines underline the need for long-term follow-up to assess the efficacy of atrial fibrillation (AF) ablation. We evaluated in patients with persistent AF and valvular heart disease the very long-term follow-up efficacy of an ablation strategy consisting of surgical pulmonary veins (PVs) isolation and left atrial linear lesions validated by electroanatomic mapping (EAM) associated with endocardial radiofrequency ablation in case of lesion incompleteness.
Methods: From 2000 to 2002, 33 patients with persistent AF and valvular heart disease underwent valve surgery and cryoablation (PVs isolation and left atrial linear lesions). Ablation scheme surgically created was validated with EAM and percutaneous transcatheter radiofrequency ablation was performed in case of lesion incompleteness.
Results: In 19/33 patients (58%) the EAM showed a complete lesion scheme, which increased to 79% (26/33) with the addition of radiofrequency ablation. At the mean follow-up of 10.7±3.1 years, 73% (24/33) of patients were in sinus rhythm (SR), whereas 27% had permanent AF. At the end of follow-up 81% of patients with a complete lesion scheme were in SR, while 43% with an incomplete one maintained SR (p=0.048).
Conclusions: In patients with persistent AF and valvular heart disease, the hybrid approach with surgical cryoablation consisting of PVs isolation and left atrial linear lesions combined with transcatheter radiofrequency ablation showed to be highly effective in maintaining SR in a very long-term follow-up. An electrophysiological evaluation, to validate the transmurality of the surgical lesions and to complete the lesion scheme applying radiofrequency energy, allowed to improve the long-term efficacy.
Preview · Article · Aug 2013 · European Heart Journal
[Show abstract][Hide abstract] ABSTRACT: New hybrid approaches for atrial fibrillation (AF) ablation, combining surgical and percutaneous procedures, are emerging to enhance the long-term success rate of these 2 procedures severally considered. Recent guidelines underline the need for long-term follow-up to really assess the efficacy of AF ablation.
From 2000 to 2002, 33 patients with long-standing persistent AF and valvular heart disease underwent valve surgery and cryoablation (pulmonary veins isolation and mitral isthmus and roof line lesions). The surgically created ablation scheme was validated with electroanatomic mapping and percutaneous radiofrequency ablation was performed in case of lesion incompleteness.
In 19 of 33 patients (58%) the electroanatomic mapping showed a complete lesion scheme, which increased to 79% (26 of 33) with the addition of radiofrequency ablation. At the mean follow-up of 10.7 ± 3.1 years, 73% (24 of 33) of patients were in sinus rhythm (SR), whereas 27% had permanent AF. At the end of follow-up 81% of patients with a complete lesion scheme were in SR, while 43% with an incomplete one maintained SR (p = 0.048).
In patients with long-standing persistent AF and valvular heart disease, the hybrid approach with surgical cryoablation consisting of pulmonary veins isolation and left atrial linear lesions combined with transcatheter radiofrequency ablation was highly effective in maintaining SR for a very long-term follow-up. Electrophysiological evaluation, to validate the transmurality of the surgical lesions and to complete the lesion scheme applying radiofrequency energy, improved the long-term efficacy.
No preview · Article · Jul 2013 · The Annals of thoracic surgery
[Show abstract][Hide abstract] ABSTRACT: Background: Current definition of persistent atrial fibrillation (PAF) enrolls a heterogeneous population with different atrial fibrillation (AF) exposure and degree of atrial substrate. Study aims were to evaluate acute and long-term results of electrical cardioversion (ECV) and to identify temporal cutoff of previous AF exposure to reclassify PAF in subgroups with different chance of sinus rhythm (SR) maintenance.
Methods: Five hundred twenty-one patients (66% men; age 69 ± 10 years) with PAF undergoing ECV, were divided in four groups according to AF duration at the time of ECV: group A with AF ≤2 months (141 patients); group B with AF >2 and ≤4 months (176 patients); group C with AF >4 and ≤6 months (89 patients); and group D with AF >6 months and <1 year (115 patients).
Results: There was no difference in term of acute success among groups (98.5% vs 97.1% vs 98.9% vs 96.5%, respectively, P = 0.95). At 5-year follow-up, 198 (41%) patients were in SR: 50% in group A, 44% in group B, 42% in group C, and 25% in group D (P < 0.001). At the multivariate analysis, previous ECV (hazard ratio [HR] 1.55, P < 0.001), left atrium enlargement (HR 1.39, P = 0.013), and AF duration >6 months at time of procedure (HR 1.59, P = 0.001) independently predict ECV failure.
Conclusion: ECV is associated with high acute success rate and low complications rate. Long-term results are strongly related with AF duration at time of ECV: a cutoff of >6 months helps in selecting patients that can take greater advantage of the procedure. (PACE 2012; 35:1126–1134)
No preview · Article · Jul 2012 · Pacing and Clinical Electrophysiology
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to clarify the role of pulmonary vein isolation (PVI) alone versus left atrial linear lesions in the treatment of permanent atrial fibrillation (AF) in patients with left atrial dilatation and valvular disease. The primary end point was to assess the persistence of sinus rhythm (SR) off antiarrhythmic drugs (AADs) at 2-year follow-up and to correlate clinical outcome with surgical results validated with electroanatomic mapping (EAM).
A total of 105 patients with permanent AF undergoing valve surgery were assigned to 3 different groups: in groups "U" and "7," left atrial linear cryoablation was performed, whereas in group "PV" patients, anatomic cryoisolation of pulmonary veins only was performed. In groups U and 7, SR was achieved in 57% of patients, whereas it was achieved in 20% of PV patients during 2-year follow-up. In the first 51 patients, the ablation schemes were validated with EAM. The EAM showed that the U lesion was never obtained: in 59% of these patients, a complete 7 lesion was achieved instead; in the 7 group, a complete 7 lesion was present in 65% of patients, whereas a complete PVI was obtained in 71% of patients. Considering patients in whom a complete 7 lesion was demonstrated with the EAM, SR without AADs was achieved in 86% of patients, whereas only 25% of patients with complete PVI were in SR without AADs.
In patients with permanent AF, left atrial dilatation and valvular heart disease linear lesions in the posterior region of the left atrium are more effective than PVI alone. With cryoablation, the surgical intent is fulfilled in only approximately 65% of the cases. Knowing the real anatomic and electrophysiological effects of surgical ablation is necessary to correctly interpret the clinical outcome.
[Show abstract][Hide abstract] ABSTRACT: Endocardial ablation of the left atrial posterior wall has been used to treat atrial fibrillation. Aim of the study was to evaluate its efficacy looking for the ablation pattern allowing a fast execution with limited interference on atrial contractility. Moreover a statistical analysis to identify predictors of long-term sinus rhythm recovery has been provided.
From April 1998 to May 2002, 95 patients with permanent (mean duration 65 months) or persistent (33%) atrial fibrillation have undergone three different ablation patterns, only 1 patient being affected by lone atrial fibrillation. Mean antero-posterior left atrial diameter was 76.2 mm. The prospective study collected information regarding variables related to patients' demographics, disease's characteristics and type of surgical ablation employed. Dependent variables were presence of sinus rhythm either at discharge and at 6 months. A logistic regression analysis was used to estimate the association between the collected variables and sinus rhythm restoration.
In-hospital and late mortality rate were 3.2 and 6.3% respectively. At discharge 67 patients (72.8%) were in sinus rhythm while at a mean follow-up of 3 years, 81.4% of 86 surviving patients are in sinus rhythm. Major adverse events rate including cardiac reoperation, pace-maker implantation and cerebrovascular accident were 8.5, 6.3 and 4.2%, respectively. Pre-operative atrial fibrillation duration, left atrial dimension and type of mitral disease did not show any correlation with long term success while the lesion pattern and the rhythm at discharge were significant predictive factors. Survival is significantly higher in patients who converted to sinus rhythm at discharge (P=0.014) with respect to those who remained in atrial fibrillation.
Permanent and persistent atrial fibrillation associated to a major cardiac disease can be safely treated with a linear ablation of the left atrial posterior wall. Satisfactory results in terms of rhythm restoration may be achieved regardless of the duration of the arrhythmia and its effects on atrial diameter. Any effort should be prompted to discharge patients in sinus rhythm. Life expectancy is longer if sinus rhythm is restored.
Preview · Article · Dec 2003 · European Journal of Cardio-Thoracic Surgery
[Show abstract][Hide abstract] ABSTRACT: We aimed to evaluate: 1) the behavior of electrical activity simultaneously in different atrial regions during atrial fibrillation (AF); 2) the difference of atrial activation between paroxysmal and chronic AF; 3) the atrial refractoriness dispersion; and 4) the correlation between the effective refractory periods (ERPs) and the FF intervals.
Little data exist on the electrophysiologic characteristics of the different atrial regions in patients with AF. A more detailed knowledge of the electrical activity during AF may provide further insights to improve treatment of AF.
Right and left atria were extensively mapped in 30 patients with idiopathic AF (18 paroxysmal and 12 chronic). In different atrial locations, we analyzed 1) the FF interval duration; and 2) the grade of organization and, in case of organized electrical activity, the direction of atrial activation. Furthermore, in patients with paroxysmal AF, we determined the atrial ERP, evaluated the ERP dispersion and assessed the presence of a correlation between the ERPs and the FF intervals.
In patients with chronic AF, we observed a shortening of the FF intervals and a greater prevalence of disorganized activity in all the atrial sites examined. In patients with paroxysmal AF, a significant dispersion of refractoriness was observed. The right lateral wall showed longer FF intervals and more organized atrial activity and, unexpectedly, the shortest mean ERPs. In contrast, the septal area showed shorter FF intervals, greater disorganization and the longest mean ERPs.
Electrical activity during AF showed a significant spatial inhomogeneity, which was more evident in patients with paroxysmal AF. The mean FF intervals did not correlate with the mean ERPs.
Full-text · Article · Mar 2001 · Journal of the American College of Cardiology
[Show abstract][Hide abstract] ABSTRACT: We sought to evaluate whether a limited surgical cryoablation of the posterior region of the left atrium was safe and effective in the cure of atrial fibrillation (AF) in patients with associated valvular heart disease.
Extensive surgical ablation of AF is a complex and risky procedure. The posterior region of the left atrium seems to be important in the initiation and maintenance of AF.
In 32 patients with chronic AF who underwent heart valve surgery, linear cryolesions connecting the four pulmonary veins and the posterior mitral annulus were performed. Eighteen patients with AF who underwent valvular surgery but refused cryoablation were considered as the control group.
Sinus rhythm (SR) was restored in 25 (78%) of 32 patients immediately after the operation. The cryoablation procedure required 20 +/- 4 min. There were no intraoperative and perioperative complications. During the hospital period, one patient died of septicemia. Thirty-one patients reached a minimum of nine months of follow-up. Two deaths occurred but were unrelated to the procedure. Twenty (69%) of 29 patients remained in SR with cryoablation alone, and 26 (90%) of 29 patients with cryoablation, drugs and radiofrequency ablation. Three (10%) of 29 patients remained in chronic AF. Right and left atrial contractility was evident in 24 (92%) of 26 patients in SR. In control group, two deaths occurred, and SR was present in only four (25%) of 16 patients.
Linear cryoablation with lesions connecting the four pulmonary veins and the mitral annulus is effective in restoration and maintenance of SR in patients with heart valve disease and chronic AF. Limited left atrial cryoablation may represent a valid alternative to the maze procedure, reducing myocardial ischemic time and risk of bleeding.
Preview · Article · Aug 2000 · Journal of the American College of Cardiology
[Show abstract][Hide abstract] ABSTRACT: It has been suggested that some atrial regions may play a role in the maintenance of atrial fibrillation (AF), whereas little is known about the presence of critical areas for the initiation of AF. It is conceivable that the identification of such critical areas may lead to more localized and selective strategies of ablative therapy.
A patient suffering from paroxysmal AF was extensively mapped in both the atria with a multielectrode basket catheter in right atrium and two decapolar catheters placed in the coronary sinus and along the left septum. During the mapping, seven identical patterns of initiation of AF were recorded. AF was initiated by an atrial premature beat (APB) arising from the superior right septum, followed by a reentrant beat originating from the same area that slowly propagated through the atria and resulted in late activation of the right lateral wall. During sinus rhythm, the majority of the electrograms were single potentials, whereas during the APB, and particularly during the first atrial reentrant beat, a high percentage of fragmented complexes was present, mainly located in the right superior septum. These fragmented complexes were present in the same sites in each initiating episode and remarkably, they showed an almost identical morphology.
This case suggests that in some patients the initiation of AF could be caused by reentrant circuits localized in specific atrial regions and the reentrant circuits could be identical in the different episodes of AF. This highlights the importance of increasing our understanding of the mechanisms of the initiation of AF so that we can identify any critical area involved in the genesis of AF where selective RF lesions may be effective in curing this arrhythmia.
No preview · Article · May 1999 · Giornale italiano di cardiologia
[Show abstract][Hide abstract] ABSTRACT: Knowledge of the electrophysiological substrates and the cure of atrial fibrillation (AF) is still unsatisfactory. The goal of this study was to evaluate the electrophysiological features of idiopathic AF and their relationship to the results of radiofrequency (RF) catheter ablation of AF and the safety and effectiveness of this procedure.
Sixteen patients with idiopathic AF underwent atrial mapping during AF and then RF ablation in the right atrium. The atrial activation was simultaneously recorded in four regions in the right atrium: high lateral wall (HL), low lateral wall (LL), high septum (HS), and low septum (LS) and in the left atrium through the coronary sinus (CS). In these regions, we evaluated the atrial fibrillation intervals (FF) and the morphological features of AF recordings by Wells' classification. No complications occurred during RF ablation. Of the 16 patients, 9 (56%) without AF recurrences during the follow-up (11 +/- 4 months) were considered successfully ablated. These patients showed a significantly shorter mean FF interval in the HS and the LS (122 +/- 32 and 126 +/- 28 ms, respectively), than in the HL and LL (159 +/- 24 and 156 +/- 28 ms, respectively). Moreover, the septum had more irregular electrical activity with greater beat-to-beat changes in FF and a higher prevalence of type III AF than the lateral region. The CS had similar behavior to the septum. Conversely, patients with unsuccessful ablation had an irregular atrial activity in the lateral wall, septum, and CS with no significant differences between the different sites.
Right atrial endocardial catheter ablation of AF is a safe procedure and may be effective in some patients with idiopathic AF. The atrial mapping during AF showed a more disorganized right atrial activation in the septum than in the lateral wall in patients with successful ablation.