Does catheter ablation cure atrial fibrillation? Single-procedure outcome of drug-refractory atrial fibrillation ablation: a 6-year multicentre experience.

Aims In the last decade, several approaches to ablating triggers and substrates of atrial fibrillation (AF) have been developed. However, most studies have reported data only on short- or medium-term follow-up. The aim of this study was to investigate whether the 1-year efficacy of catheter ablation for AF is predictive of long-term clinical success. Methods and results Between February 2001 and October 2003, 229 consecutive patients affected by drug-refractory paroxysmal or persistent AF underwent a single radiofrequency catheter ablation procedure (anatomical approach in 146 patients and electrophysiologically guided approach in 83 patients). Of these patients, 177 (mean age 59.1 +/- 10.5 years, 57.6% with paroxysmal AF) were free from any atrial arrhythmia recurrence after 12 months. These 177 patients were subsequently followed up for at least another 24 months, by means of electrocardiogram and 24 h Holter monitoring. After a mean follow-up of 49.7 +/- 13.3 months (range 36-83 months), 58.2% of the patients were free from any atrial arrhythmia recurrence (39.5% without antiarrhythmic drugs). The actuarial atrial arrhythmia recurrence rate was 13.0% at 2 years, 21.8% at 3 years, 35.0% at 4 years, 46.8% at 5 years, and 54.6% at 6 years. Atrial arrhythmia-free survival was similar in patients with paroxysmal or persistent AF, with and without antiarrhythmic drugs during the follow-up, who underwent electrophysiologically guided pulmonary vein (PV) isolation or anatomical PV ablation. Conclusion Even patients in whom catheter ablation prevents AF recurrence for 1 year should not be considered 'cured', since >40% of them will suffer AF recurrence over a long-term clinical follow-up.

Role of pulmonary veins isolation in persistent atrial fibrillation ablation: the pulmonary vein isolation in persistent atrial fibrillation (PIPA) study.

BACKGROUND: The role of pulmonary veins (PV) isolation in patients with persistent atrial fibrillation (AF) is still debated. The aim of this study was to evaluate the adjunctive role of PV isolation in patients with persistent AF who underwent circumferential PV ablation (anatomical approach). METHODS: We treated 97 consecutive patients presenting with drug-refractory persistent AF by an anatomical approach (group A, n = 36, mean age = 60 +/- 8 years, 29 males) or an integrated approach (group B, n = 61, mean age 59 +/- 10 years, 48 males). In all patients, radiofrequency (RF) ablation was performed by means of a nonfluoroscopic navigation system, in order to anatomically create circumferential lines around the PV. In group B, the persistence of PV potentials was ascertained with a multipolar circular catheter. If PV potentials persisted, RF energy targeting the electrophysiological breakthroughs was delivered to disconnect the PV. Past a 2-month period of observation, success was defined as absence of any atrial tachyarrhythmia recurrence lasting >30 seconds. RESULTS: Total procedure duration (220 +/- 62 minutes vs 140 +/- 43 minutes, P < 0.001), fluoroscopy time (35 +/- 15 minutes vs 17 +/- 9 minutes, P < 0.001), and RF delivery time (48 +/- 22 minutes vs 27 +/- 9 minutes, P < 0.001) were significantly longer in group B than in group A. One cardiac perforation occurred in group A. After 15 +/- 9.1 months, 21 patients in group A (58%) and 34 patients in group B (56%) were free of atrial tachyarrhythmia recurrence (P = 0.9). CONCLUSIONS: In patients with persistent AF, who underwent an anatomical approach, electrophysiological confirmation of PV disconnection significantly increased the fluoroscopy and procedural times, without effect on the long-term outcomes.

Long-term outcomes of CRT-PM versus CRT-D recipients.

OBJECTIVE: To compare the rates of all-cause mortality in recipients of cardiac resynchronization therapy devices without (CRT-PM) versus with defibrillator (CRT-D). METHODS: Between February 1999 and July 2004, 233 patients (mean age = 69 +/- 8 years, 180 men) underwent implantation of CRT-PM or CRT-D devices. New York Heart Association (NYHA) heart failure functional class II was present in 11%, class III in 69%, and class IV in 20% of patients; mean left ventricle ejection fraction (LVEF) was 26.5 +/- 6.5 %, 48% presented with idiopathic dilated cardiomyopathy and 49% with ischemic heart disease. Cox multiple variable regression analysis was performed in search of predictors of death. RESULTS: The clinical characteristics of the 117 CRT-PM and 116 CRT-D recipients were similar, except for LVEF (28.2 +/- 6.2% vs 25.0 +/- 6.5%, respectively; P < 0.001), and ischemic versus nonischemic etiology of heart failure (41% vs 56%, respectively P = 0.02). Over a mean follow-up of 58 +/- 15 months, no significance difference in overall mortality rate was observed between the two study groups. Male sex, NYHA functional class IV, and atrial fibrillation at implant were significant predictors of death. CONCLUSIONS: There was no difference in long-term survival rate among patients with CRT-D versus CRT-PM, although CRT-D more effectively lowered the sudden death rate. Male sex, NYHA functional class IV, and atrial fibrillation predicted the worst prognosis.

Early complications of pulmonary vein catheter ablation for atrial fibrillation: a multicenter prospective registry on procedural safety.

BACKGROUND: Data on the procedural safety of pulmonary vein radiofrequency catheter ablation for atrial fibrillation (AF) are as yet scant. OBJECTIVE: The aims of the present study were to prospectively evaluate the incidence of early complications of pulmonary vein ablation for AF in an unselected population of consecutive patients, and to identify possible predictors. METHODS: From April 2005 to October 2006, data from 1,011 consecutive patients who were undergoing radiofrequency catheter ablation for every type of AF in 10 Italian centers were collected. All complications occurring from the admission of the patient up to the 30th day were considered. RESULTS: No procedure-related death was observed. Complications occurred in 40 patients (3.9%): 12 (1.2%) had peripheral vascular complications, 8 (0.8%) had conservatively treated pericardial effusion, 6 (0.6%) had cardiac tamponade (successfully drained), 5 (0.5%) had cerebral embolisms, 4 (0.4%) presented pulmonary vein stenosis >50%, and 5 (0.5%) presented other isolated adverse events. History of coronary artery disease (odds ratio 5,603, 95% confidence interval 1,559 to 20,139, P < .008) characterized patients who presented with hemorrhagic complications. CONCLUSION: Early complications of pulmonary vein catheter ablation seem to be fewer than in the early years of AF ablation, but still occur in 3.9% of procedures.

Role of transtelephonic electrocardiographic monitoring in detecting short-term arrhythmia recurrences after radiofrequency ablation in patients with atrial fibrillation.

OBJECTIVES: The aim of our study was to determine the incidence of asymptomatic recurrences of atrial fibrillation (AF) by daily transtelephonic (TT) electrocardiographic (ECG) monitoring, as compared with standard ECG and 24-h Holter recording, in patients who underwent radiofrequency catheter ablation (RCA) of AF. BACKGROUND: The efficacy of RCA of AF is usually evaluated by means of patients' symptoms. METHODS: Seventy-two patients with paroxysmal (n = 37) or persistent (n = 35) drug-refractory AF underwent circumferential RCA of the pulmonary vein (PV) ostia. Left isthmus ablation was performed in 57 patients, and cavotricuspid isthmus ablation was done in 69 patients. Patients were scheduled to obtain an ECG and Holter recordings one and four months after ablation, as well as a daily TT ECG, from 30 to 120 days after ablation or in the event of symptoms. RESULTS: A total of 5,585 TT ECGs were obtained (mean 77.5 per patient). In 20 patients (27.8%), AF recurrences were recorded during TT ECG, whereas ECG and Holter monitoring revealed AF recurrences in 10 patients (13.9%, p = 0.001). Ten patients had at least one asymptomatic AF recurrence, and eight were completely asymptomatic. The ECG recorded in the event of symptoms always showed AF. CONCLUSIONS: Transtelephonic ECG is better than standard ECG and 24-h Holter recordings in evaluating AF relapses after RCA, thus decreasing the short-term success of ablation from 86% to 72%. The absence of symptoms should not be interpreted as absence of AF, as 50% of patients were asymptomatic during at least one AF episode.

Is pulmonary vein isolation necessary for curing atrial fibrillation?

BACKGROUND: Pulmonary veins (PVs) play a pivotal role in initiating and perpetuating atrial fibrillation (AF). We investigated if PV electrical isolation from the left atrium is required for curing AF. METHODS AND RESULT: Fifty-one patients with paroxysmal or persistent AF underwent circumferential radiofrequency ablation of PV ostia performed with an anatomic approach. The end point of the ablation procedure was the recording of low peak-to-peak bipolar potentials (<0.1 mV) inside the lesions. Left atrium pacing was used to assess the conduction between the PVs and the left atrium. During a mean follow-up period of 16.6+/-3.9 months, 41 patients (80.4%) were free of atrial arrhythmias. When patients with and without AF recurrence were analyzed, no significant difference was observed in the mean number of PVs in which the ablation end point was reached (3.4+/-1.2 versus 3.7+/-0.87) and PVs isolated (1.5+/-1.4 versus 1.6+/-1). We noted that, although in 29 of 41 patients (71%) without AF recurrence, the ablation end point was reached in all PVs mapped, it was only possible to demonstrate the isolation of all PVs mapped in 2 patients. On the other hand, in 7 of 10 patients (70%) with AF recurrence, the ablation end point was reached in all PVs mapped, whereas one patient had all PVs isolated. CONCLUSIONS: Our findings show that with the use of a pure anatomic approach, it is possible to prevent AF in >80% of patients undergoing catheter ablation. Moreover, the isolation of PVs is not crucial for curing AF.

Sequential biventricular resynchronization optimized by myocardial strain rate analysis: a case report.

We report the case of a patient with severe left ventricular systolic dysfunction and left bundle branch block in whom cardiac resynchronization therapy (CRT) was optimized by tissue Doppler imaging. A horizontal mechanical asynchrony index was derived from tissue Doppler regional longitudinal strain rate profiles as the time difference at the onset of shortening between septum, lateral, anterior and inferior walls. The interventricular delay was modulated in order to achieve the smallest asynchrony index; on the basis of this parameter a sequential (S)-CRT with a left ventricular pre-excitation of 20 ms was definitively programmed. This optimized S-CRT was followed by an acute improvement in systolic cardiac performance and by a long-term (12 months) clinical benefit as well as by a documented decrease in LV chamber size due to a true reverse remodeling effect. Thus, in some patients S-CRT may be more effective than conventional CRT. Tissue Doppler-derived strain rate analysis can provide information on the degree of left intraventricular asynchrony allowing the modulation of a tailored interventricular delay.

Documentation of pulmonary vein isolation improves long term efficacy of persistent atrial fibrillation catheter ablation.

BACKGROUND: The aim of this study was to investigate the efficacy of catheter ablation in the treatment of persistent atrial fibrillation (AF) and the predictors of arrhythmia recurrence. METHODS: Absence of atrial tachyarrhythmia (AT) recurrence during a mid-term follow-up was correlated with several clinical and procedural characteristics in a population of 82 patients aged 20-70 years who had experienced at least one documented relapse of persistent AF during a single trial of antiarrhythmic drug therapy. Electrophysiological success of ablation was declared when all identified PVs were isolated (confirmation of entry and exit block). Patients were followed for a maximum of 24 months after the blanking period with outpatient visits, ECG recordings, 24-hour Holter monitoring, and weekly transtelephonic monitoring for 30s. RESULTS: Electrophysiological success was documented in 38/82 (46.3%) patients. During a mean follow-up of 24.7 ± 4.2 months, 69/82 (84.1%) patients presented at least one episode of AT after the 2 month blanking period. According to univariate and multivariate logistic regression analyses, only an electrophysiologically successful ablation significantly correlated with the absence of documented AT relapse (OR 5.32, 95% CL 1.02-27.72; p=.0472). CONCLUSIONS: Mid-term outcome of a single procedure of catheter ablation without the adjunction of antiarrhythmic drug therapy is poor in patients with persistent AF. Documented PV isolation is useful to increase the success rate of circumferential PV ablation even in persistent AF patients.

Appropriate therapies predict long-term mortality in primary and secondary prevention of sudden cardiac death.

BACKGROUND: Less than 50% of patients implanted with an implantable cardioverter-defibrillator (ICD) receive device therapy during the follow-up. The aim of our study was to prospectively evaluate the predictive role of appropriate ICD therapy on long-term survival of patients implanted for primary or secondary sudden death prevention. METHODS: From 2002 to 2003, 139 consecutive patients [mean age 66±9 years, male 77%, ischemic heart disease 56%, New York Heart Association functional class >II (74%), primary prevention 74%, mean left ventricular ejection fraction 30±9%, cardiac resynchronization ICD 65%] were enrolled. We collected and evaluated device therapies for at least 18 months and recorded survival status for more than 5 years. RESULTS: Over a median follow-up of 18 months, 54 (39%) patients received at least one ICD intervention, with 28 patients receiving only appropriate ICD therapies, 13 only inappropriate therapies and 13 receiving both therapies. At a mean follow-up of 63±12 months, 30 deaths occurred in 130 patients (23%); for nine patients, we had no survival status information. Death was classified as cardiac in 22 (73%) patients, the most common cause was progressive heart failure. In a Cox proportional regression model, an appropriate ICD therapy was associated with a significant increase in the subsequent risk of death (hazard ratio 3.02, P=0.003). CONCLUSION: In patients implanted with ICD or cardiac resynchronization therapy with ICD devices, for primary or secondary sudden cardiac death prevention, appropriate ICD therapy predicts a three-fold greater risk of death.

Feasibility and efficacy of electrical cardioversion after cardiac resynchronization implantation in patients with permanent atrial fibrillation.

PURPOSE: Patients with permanent atrial fibrillation (AF) who undergo cardiac resynchronization therapy (CRT) may spontaneously recover sinus rhythm during follow-up. We tested the feasibility and efficacy of electrical cardioversion attempted after 3 months of CRT in patients with permanent AF and measured the long-term maintenance of sinus rhythm. METHODS: Twenty-eight consecutive patients with permanent AF in whom CRT defibrillators had been implanted were scheduled for internal electrical cardioversion after 3 months (group A) and were compared with a control group of 27 patients (group B). RESULTS: In group A, 22 patients (79 %) were eligible for cardioversion; sinus rhythm was restored in 18 (82 %) of these, with no procedural complications. After 12 months, 16 patients (58 %) in group A were in sinus rhythm, compared with one group B patient who spontaneously recovered sinus rhythm (4 %, p < 0.001). On 12-month evaluation, ejection fraction had improved in both groups, but a reduction in left ventricular end-systolic volume was recorded only in group A patients (p = 0.018 versus baseline). CONCLUSIONS: In patients with permanent AF, the rhythm control strategy consisting of internal cardioversion, performed by means of the implanted cardioverter-defibrillator after 3 months of CRT, was associated with a high rate of sinus rhythm resumption on long-term follow-up and with a better echocardiographic response to CRT than that seen in patients treated according to a rate control strategy.

Clinical and technical determinants of long-term performance of coronary sinus leads.

OBJECTIVES: Little is known about coronary sinus lead performance in patients with cardiac resynchronization therapy devices. We evaluated the impact of clinical and technical parameters on coronary sinus lead performance over long-term follow-up. METHODS: From February 1999 to July 2004, 235 patients (181 men; mean age, 68 +/- 9 years; mean left ventricular ejection fraction, 26.5 +/- 6.5%; idiopathic dilated cardiomyopathy, 49%; ischemic, 48%; and other cause, 3%) underwent cardiac resynchronization therapy (pacemaker or defibrillator) implantation. RESULTS: On implantation, the only statistically significant difference was observed in mean pacing impedance, which was lower for unipolar leads than for bipolar leads (763 +/- 250 vs. 847 +/- 270 Omega, P = 0.02), and lower in patients with ischemic cardiomyopathy than in those with idiopathic cardiomyopathy (758 +/- 204 vs. 837 +/- 291 Omega, P = 0.03). After a mean follow-up of 41.7 +/- 14.7 months, a significant decrease was observed in mean pacing impedance (from 811 +/- 261 to 717 +/- 284 Omega, P = 0.0026) and mean R-wave amplitude (from 13.2 +/- 6.7 to 10.5 +/- 5.5 mV, P = 0.002), whereas the mean pacing energy threshold increased from 3.6 +/- 10.4 to 9.5 +/- 28 microJ (P = 0.004). On analysis of variance, unipolar lead (P = 0.016) and posterior coronary sinus position (P = 0.049) were related to a greater energy threshold increase. On multivariate analysis (Cox regression), only posterior coronary sinus lead position (P = 0.013) proved to be an independent predictor of long-term significant increase in the stimulation energy threshold. CONCLUSION: Over the long-term follow-up of coronary sinus leads, pacing impedance and R-wave amplitude decreased, whereas the energy threshold increased; unipolar leads and posterior lead location in the coronary sinus were related to a greater energy threshold increase.

Cardiac resynchronization therapy: a review of CRT-D versus CRT-P.

Current evidence-based guidelines recommend an implantable cardioverter-defibrillator for the primary prevention of sudden cardiac death in selected patients with impaired left ventricular function, and cardiac resynchronization therapy for improvement of symptoms and survival in selected patients with impaired left ventricular function and abnormal ventricular conduction. Many patients may be eligible for both treatments, but it does not necessarily follow that such patients would obtain additional benefit from the combined treatment over one treatment alone. A simple pragmatic approach would be to use resynchronisation therapy, in order to reduce symptoms and extend life in patients with New York Heart Association class III or IV heart failure, with the addition of an implantable cardioverter-defibrillator left to clinical judgment on an individual basis when additional indications exist. When such an addition is contemplated the hypothesized incremental benefits in survival would need to be balanced by the possible increase in morbidity owing to, for example, inappropriate shocks.

High prevalence of cooled tip use as compared with 8-mm tip in a multicenter Italian registry on atrial fibrillation ablation: focus on procedural safety.

BACKGROUND: Whether cooling catheters should be preferred for atrial fibrillation (AF) ablation is not yet clear. METHODS: From April 2005 to October 2006, 991 (74% men) consecutive patients who underwent AF ablation were prospectively enrolled in 10 Italian centers. For the present subanalysis, patients were ranked in the two study groups on the basis of the catheter system chosen: 8-mm tip was used in 86 patients (9% conventional group) and open-irrigated tip in 905 patients (91% cooled group). RESULTS: The registry clinical data of both groups showed marked heterogeneity due to the fact that the higher number of patients of the cooled group had longer AF history (4.9+/-4.1 versus 1.2+/-1.8 years; P=0.0001), permanent/persistent AF (41.2 versus 27.9%; P=0.01), and larger left atrium (LA) size (44.1+/-6.2 versus 33.4+/-10.5 mm; P