Impact of atrial fibrillation-induced tachycardiomyopathy in patients undergoing pulmonary vein isolation.

INTRODUCTION: Atrial fibrillation (AF) is a recognized treatable cause of tachycardiomyopathy (TMP), with class IIb indication for catheter ablation (CA). The aim of this study is to analyze the prevalence, clinical characteristics and effect of CA in patients with TMP and to evaluate TMP as a prognostic factor for AF recurrence in these patients (TMP group), compared to controls with normal left ventricular ejection fraction (LVEF) and patients with heart failure due to structural cardiomyopathy (HF group). METHODS AND RESULTS: The study groups included 659 consecutive patients undergoing CA between 2003 and 2011: TMP group (n = 61), HF group (n = 36) and control group (n = 562). Compared to controls, patients with TMP were younger, had a shorter AF course and more often had persistent AF. Regarding echocardiographic parameters, the TMP group had lower LVEF (40% vs. 62%, P < 0.05), larger left atrial diameter (LAD: 46 vs. 41 mm, P < 0.05) and LV end-diastolic diameter (LVEDD: 55 vs. 51 mm, P < 0.05) compared to controls, with significant improvement at six-month follow-up, including those patients with AF recurrence. The probability of being arrhythmia-free did not differ between the TMP group and the other groups after a first or last procedure. The only independent predictor of AF recurrence was LAD. CONCLUSIONS: Patients with tachycardiomyopathy secondary to AF benefit from CA, with a significant improvement in LVEF, LVEDD and LAD. The outcome after CA of this group did not differ from patients with no structural cardiomyopathy.

Evolución de la mejora en los resultados y las complicaciones de la ablación por catéter de la fibrilación auricular: aprendizaje, técnicas y metodología / Improved outcomes and complications of atrial fibrillation catheter ablation over time: learning curve, techniques, and methodology

Introducción y objetivos. Los resultados y las complicaciones del procedimiento de ablación de fibrilación auricular varían ampliamente entre los diferentes centros. Nuestro objetivo es analizar los resultados y las complicaciones derivadas de este procedimiento en nuestro centro e identificar los factores predictores de éxito y de seguridad. Métodos. Entre 2002 y 2009 se realizó un total de 726 procedimientos de ablación de fibrilación auricular. Basándonos en la aplicación sistemática de un protocolo de anticoagulación y sedación consciente desde enero 2008, podemos establecer dos estrategias de ablación que constituyen dos grupos bien diferenciados: grupo A, constituido por 419 procedimientos realizados antes de enero 2008, y grupo B, formado por 307 procedimientos realizados después. Resultados. El 60,9% de los pacientes no presentaron recurrencia arrítmica tras varios procedimientos durante un seguimiento medio de 8,7 meses. Con un único procedimiento, la tasa total de éxito fue del 41%, significativamente mayor entre los pacientes del grupo B (el 51,6 frente al 35,2% de éxito en el grupo A; p = 0,001). Hubo un total de 31 complicaciones mayores (4,2%); 26 en el grupo A (6,2%) y 5 en el grupo B (1,6%) (p = 0,002). La protocolización del procedimiento fue un factor predictor de la ausencia de complicaciones (odds ratio = 0,406; intervalo de confianza del 95%, 0,214-0,769; p < 0,006). Conclusiones. La aplicación sistemática de un protocolo de anticoagulación y sedación consciente se asocia a la mejora de los resultados y la reducción de las complicaciones en el procedimiento de ablación de fibrilación auricular. Otros factores no evaluados en este estudio, como la curva de aprendizaje de los operadores y la progresiva mejora tecnológica, pueden haber influido en los cambios observados (AU)

Introduction and objectives. The outcomes of atrial fibrillation ablation procedures vary widely between different centers. Our objective was to analyze the results and complications of this procedure in our center and identify factors predicting the efficacy and safety of atrial fibrillation ablation. Methods. In total, 726 atrial fibrillation ablation procedures were performed in our center between 2002 and 2009. Beginning in January 2008, a protocol for anticoagulation and conscious sedation was systematically applied. Outcomes and complications could therefore be compared in 2 well-differentiated groups: group A included 419 procedures performed prior to 2008 and group B included 307 procedures completed after 2008 using the new protocol. Results. During an average follow-up of 8.7 months, 60.9% of patients were arrhythmia-free after one or repeat procedures. After only 1 procedure, the success rate was 41% and significantly higher in group B (51.6% vs 35.2% in group A; P=.001). There were 31 major complications (4.2%), 26 in group A (6.2%) and 5 in group B (1.6%) (P=.002). The implementation of the new protocol was an independent predictor of the absence of complications (odds ratio=0.406; 95% confidence interval, 0.214-0.769; P<.006). Conclusions. Systematic application of an anticoagulation and conscious sedation protocol is associated with improved results and fewer complications of atrial fibrillation ablation. Factors not evaluated in the present study, such as operator experience and ongoing improvements in atrial fibrillation ablation technology, could have influenced these findings (AU)

Improved outcomes and complications of atrial fibrillation catheter ablation over time: learning curve, techniques, and methodology.

INTRODUCTION AND OBJECTIVES: The outcomes of atrial fibrillation ablation procedures vary widely between different centers. Our objective was to analyze the results and complications of this procedure in our center and identify factors predicting the efficacy and safety of atrial fibrillation ablation. METHODS: In total, 726 atrial fibrillation ablation procedures were performed in our center between 2002 and 2009. Beginning in January 2008, a protocol for anticoagulation and conscious sedation was systematically applied. Outcomes and complications could therefore be compared in 2 well-differentiated groups: group A included 419 procedures performed prior to 2008 and group B included 307 procedures completed after 2008 using the new protocol. RESULTS: During an average follow-up of 8.7 months, 60.9% of patients were arrhythmia-free after one or repeat procedures. After only 1 procedure, the success rate was 41% and significantly higher in group B (51.6% vs 35.2% in group A; P=.001). There were 31 major complications (4.2%), 26 in group A (6.2%) and 5 in group B (1.6%) (P=.002). The implementation of the new protocol was an independent predictor of the absence of complications (odds ratio=0.406; 95% confidence interval, 0.214-0.769; P<.006). CONCLUSIONS: Systematic application of an anticoagulation and conscious sedation protocol is associated with improved results and fewer complications of atrial fibrillation ablation. Factors not evaluated in the present study, such as operator experience and ongoing improvements in atrial fibrillation ablation technology, could have influenced these findings.

Low efficacy of atrial fibrillation ablation in severe obstructive sleep apnoea patients.

AIMS: Atrial fibrillation (AF) ablation efficacy varies according to patients' clinical characteristics. Although the association of obstructive sleep apnoea (OSA) and AF is well established, data on AF ablation efficacy in OSA are scarce. The aim of this study was to clarify the effect of OSA on the outcome of AF ablation. METHODS AND RESULTS: A series of 174 consecutive patients without polysomnography submitted to circumferential pulmonary vein ablation were included in the study. All patients were assessed by Berlin Questionnaire (BQ) and underwent an echocardiogram and a clinical evaluation. Patients with a high BQ score, indicating high risk for OSA, participated in a sleep study. Diagnoses were classified according to the apnoea-hypoapnoea index (AHI) as mild (AHI < 10/h), non-severe (AHI < 30/h), or severe (AHI >or= 30/h) OSA. Follow-up consisted of outpatient visits and 24 or 48 h Holter monitoring at 1, 4, and 7 months, and every 6 months thereafter. Any episode of AF or left atrial (LA) flutter was considered recurrence. Fifty-one (29.3%) patients had high BQ scores. The sleep study showed that 17 (9.8%) and 25 (14.4%) of these patients had non-severe and severe OSA, respectively. One-year arrhythmia-free probability after a single ablation procedure was 48.5% in patients with low risk for OSA (low BQ score or AHI < 10/h), 30.4% in the non-severe OSA group (10 < AHI < 30/h) and 14.3% in the severe OSA group (AHI >or= 30). Anteroposterior LA diameter [hazard ratio (HR) = 1.046, 95% confidence interval (CI): 1.005-1.089; P = 0.029] and severe OSA (HR = 1.870, 95% CI: 1.106-3.161; P = 0.019) were the independent predictors of arrhythmia recurrence. CONCLUSION: In patients with AF ablation, the presence of severe OSA is an independent predictor for AF ablation failure.

Efficacy of circumferential pulmonary vein ablation of atrial fibrillation in endurance athletes.

AIMS: Long-term endurance sport practice has been increasingly recognized as a risk factor for lone atrial fibrillation (AF). However, data on the outcome of circumferential pulmonary vein ablation (CPVA) in endurance athletes are scarce. The aim of the study was to evaluate the efficacy of CPVA in AF secondary to endurance sport practice. METHODS AND RESULTS: Patients submitted to CPVA answered a questionnaire about lifetime history of endurance sport practice. Endurance athletes were defined as those who engaged in >3 h per week of high-intensity exercise for at least the 10 years immediately preceding their AF diagnosis. A series of 182 consecutive patients was included (51 +/- 11 years, 65% with paroxysmal AF, 81% men, 42 +/- 6 mm mean left atrial diameter); 107 (59%) patients had lone AF, and 42 of them (23% of the study population) were classified as endurance athletes (lone AF sport group). Freedom from arrhythmia after a single CPVA was similar in the lone AF sport group compared with the remaining patients (P = 0.446). Left atrial size and long-standing AF were the only independent predictors for arrhythmia recurrence after ablation. CONCLUSION: Circumferential pulmonary vein ablation was as effective in AF secondary to endurance sport practice as in other aetiologies of AF.