Initial rhythm control with cryoballoon ablation vs drug therapy: Impact on quality of life and symptoms.

BACKGROUND: Cryoballoon ablation (CBA) as a first-line rhythm control strategy is superior to antiarrhythmic drugs (AADs) for preventing atrial fibrillation (AF) recurrence; the impact of first-line CBA on quality of life (QoL) and symptoms has not been well characterized. METHODS: Patients aged 18 to 75 with symptomatic paroxysmal AF naïve to rhythm control therapy were randomized (1:1) to CBA (Arctic Front Advance, Medtronic) or AAD (Class I or III). Symptoms and QoL were assessed at baseline, 1, 3, 6, 9, and 12 months using the EHRA classification and Atrial Fibrillation Effect on QualiTy-of-Life (AFEQT) and SF-36v2 questionnaires. Symptomatic palpitations were evaluated via patient diary. RESULTS: Overall, 107 patients were randomized to CBA and 111 to AAD; crossovers occurred in 9%. Larger improvements in the AFEQT summary, subscale and treatment satisfaction scores were observed at 12 months with CBA vs AAD (all P <0.05). At 12 months, the mean adjusted difference in the AFEQT summary score was 9.9 points higher in the CBA group (95% CI: 5.5 -14.2, P <0.001). Clinically important improvements in the SF-36 physical and mental component scores were observed at 12 months in both groups, with no significant between group differences at this timepoint. In the CBA vs AAD group, larger improvements in EHRA class were observed at 6, 9 and 12 months (P <0.05) and the incidence rate of symptomatic palpitations was lower (4.6 vs 15.2 days/year post-blanking; IRR: 0.30, P <0.001). CONCLUSIONS: In patients with symptomatic AF, first-line CBA was superior to AAD for improving AF-specific QoL and symptoms. TRIAL REGISTRATION: ClinicalTrials.gov number: NCT01803438.

Cryoballoon ablation vs. antiarrhythmic drugs: first-line therapy for patients with paroxysmal atrial fibrillation.

AIMS: Treatment guidelines for patients with atrial fibrillation (AF) suggest that patients should be managed with an antiarrhythmic drug (AAD) before undergoing catheter ablation (CA). This study evaluated whether pulmonary vein isolation employing cryoballoon CA is superior to AAD therapy for the prevention of atrial arrhythmia (AA) recurrence in rhythm control naive patients with paroxysmal AF (PAF). METHODS AND RESULTS: A total of 218 treatment naive patients with symptomatic PAF were randomized (1 : 1) to cryoballoon CA (Arctic Front Advance, Medtronic) or AAD (Class I or III) and followed for 12 months. The primary endpoint was ≥1 episode of recurrent AA (AF, atrial flutter, or atrial tachycardia) >30 s after a prespecified 90-day blanking period. Secondary endpoints included the rate of serious adverse events (SAEs) and recurrence of symptomatic palpitations (evaluated via patient diaries). Freedom from AA was achieved in 82.2% of subjects in the cryoballoon arm and 67.6% of subjects in the AAD arm (HR = 0.48, P = 0.01). There were no group differences in the time-to-first (HR = 0.76, P = 0.28) or overall incidence [incidence rate ratio (IRR)=0.79, P = 0.28] of SAEs. The incidence rate of symptomatic palpitations was lower in the cryoballoon (7.61 days/year) compared with the AAD arm (18.96 days/year; IRR = 0.40, P < 0.001). CONCLUSIONS: Cryoballoon CA was superior to AAD therapy, significantly reducing AA recurrence in treatment naive patients with PAF. Additionally, cryoballoon CA was associated with lower symptom recurrence and a similar rate of SAEs compared with AAD therapy.

Cryoballoon catheter ablation versus antiarrhythmic drugs as a first-line therapy for patients with paroxysmal atrial fibrillation: Rationale and design of the international Cryo-FIRST study.

BACKGROUND: Radiofrequency current (RFC) catheter ablation for patients with paroxysmal atrial fibrillation (AF) has been shown to be safe and effective in first-line therapy. Recent data demonstrates that RFC ablation provides better clinical outcomes compared to antiarrhythmic drug (AAD) in the treatment of early AF disease. Furthermore, studies comparing RFC and cryoballoon have established comparable efficacy and safety of pulmonary vein isolation (PVI) for patients with symptomatic paroxysmal AF. OBJECTIVES: The Cryo-FIRST trial was designed to compare AAD treatment against cryoballoon PVI as a first-line therapy in treatment naïve patients with AF. Efficacy and safety will be compared between the two cohorts and amongst subgroups. METHODS: The primary hypothesis is that cryoablation is superior to AAD therapy. To test this hypothesis, patients will be randomized in a 1:1 design. Using a 90-day blanking period, primary efficacy endpoint failure is defined as (at least) one episode of atrial arrhythmia with a duration >30 sec (documented by 7-day Holter or 12-lead ECG). Secondary endpoints (Quality-of-Life, rehospitalization, arrhythmia recurrence rate, healthcare utilization, and left atrial function) and adverse events will also be evaluated. Study enrollment will include 218 patients in up to 16 centers. CONCLUSIONS: This study will be a multi-national randomized controlled trial comparing cryoablation against AAD as a first-line treatment in patients with paroxysmal AF. The results may help guide the selection of patients for early AF disease therapy via cryoballoon ablation.

Predictors of early and late left atrial tachycardia and left atrial flutter after catheter ablation of atrial fibrillation: long-term follow-up.

BACKGROUND: The aim of the study was identification of the predictors of left atrial tachycardia and left atrial flutter (LATAFL) after radiofrequency catheter ablation of atrial fibrillation (CAAF). METHODS: We followed 598 patients (71% male, 41% paroxysmal AF; median follow-up: 36 months) after a single step-wise CAAF procedure. The time to first documented LATAFL lasting longer than 30 s, documented in any kind of electrocardiography (ECG), was defined as an end-point. RESULTS: A single CAAF procedure resulted in LATAF in 58 (10%) patients. Additional lesions were performed in 275 (46%) patients. Early LATAFL recurrence (£ 3 months since the index procedure) was observed in 11 (2%) patients. Late LATAFL (> 3 months) was noted in 47 (8%) patients. The univariate predictors of LATAFL recurrence were: type of AF (p = 0.003), the size of LA (p = 0.002) and the type of procedure (p = 0.0001). The identified single independent predictors of LATAFL recurrence were enlarged LA (p = 0.001) and mul-tiple (≥ 2) additional lesions performed during the index procedure (p < 0.0001). CONCLUSIONS: Higher rate of LATAFL recurrence was observed in patients with non-paroxysmal AF, enlarged LA and any additional lesions performed. Two independent predictors of LATAFL recurrence after CAAF were: the enlarged LA and multiple (≥ 2) additional lesions performed during the index procedure.

Cryoballoon ablation of atrial fibrillation: How important is the proper selection of patients?

BACKGROUND: Relation between pre-procedural selection of patients and the success rate after a single cryoballoon ablation (CAB) procedure is unknown. METHODS: CAB was performed in 378 (65% male, median age 58 years, 85% paroxysmal atrial fibrillation [AF]) consecutive patients with symptomatic and drug refractory AF. The combined ALARMEc (Atrial fibrillation type, Left Atrium size, Renal insufficiency, Metabolic syndrome, cardiomyopathy) risk score was calculated for each individual patient. The end-point of the study was the first AF, atrial flutter or atrial tachycardia recurrence after the 3-month blanking period in the 1-year follow-up since the index procedure, in the absence of anti-arrhythmic (class I and III) therapy. RESULTS: Single and multi-catheter approach was used in 79% and 21% of patients, respectively. The acute success rate with single and multi-catheter approach was 79% and 99%, respectively. The overall 1-year success rate after a single CAB procedure was 70%. The 1-year outcome was: 83%, 70%, 60%, 40% and 29% in patients with ALARMEc risk score: 0, 1, 2, 3 and 5, respectively. Total rate of complications was 11%, including transient phrenic nerve palsy in 9.5% of cases. CONCLUSIONS: Multi-catheter approach was needed in 21% of patients to achieve acute pulmonary vein isolation. Patients with low (≤ 1) ALARMEc risk score, preferably young individuals with sole paroxysmal AF (ALARMEc = 0), are best candidates for CBA procedure. Performing CBA in patients with higher (> 2) ALARMEc risk score should be avoided. Phrenic nerve palsy was a transient complication.

Ablación con criobalón en pacientes jóvenes con fibrilación auricular paroxística aislada / Cryoballoon Ablation in Young Patients With Lone Paroxysmal Atrial Fibrillation

Introducción y objetivos Todavía no se conoce la eficacia a largo plazo de la ablación con criobalón de la fibrilación auricular paroxística aislada. Se presentan los resultados de un seguimiento a largo plazo de la intervención de ablación con un solo criobalón. Métodos Se llevó a cabo el aislamiento de la vena pulmonar en 103 pacientes (72 varones; mediana de edad, 52 años) con fibrilación auricular paroxística aislada sintomática. El objetivo de este estudio observacional de cohorte era la primera recurrencia de la arritmia (fibrilación auricular, taquicardia auricular o aleteo auricular) documentada mediante electrocardiograma en un seguimiento de 5 años, en ausencia de tratamiento antiarrítmico. Resultados Se estableció aislamiento completo agudo de la vena pulmonar en el 86% de los pacientes con un solo criobalón. Las tasas de éxito a los 6 meses, 1 año y 5 años tras una sola intervención fueron del 94, el 91 y el 77% respectivamente. Se observó recurrencia de la arritmia en 24 casos, tras una mediana de 14,8 [intervalo, 8,0-16,8] meses. Se controló bien solo con bloqueadores beta a 13 pacientes sintomáticos; 7 pacientes sintomáticos recibieron tratamiento antiarrítmico (de clase I C en 5 pacientes; dronedarona en 2) que se introdujo durante el periodo de aclaramiento. Dos de ellos presentaron una recurrencia temprana de la arritmia solamente durante el periodo de aclaramiento; se mantuvieron sin arritmia en el seguimiento posterior durante el tratamiento con dronedarona. La tasa de complicaciones fue relativamente baja e incluyó una incidencia del 4,8% de parálisis transitoria del nervio frénico. Conclusiones: Una intervención de ablación con un solo criobalón para la fibrilación auricular paroxística aislada produjo tasas altas de eficacia aguda y a medio y largo plazo. La tasa de complicaciones fue relativamente baja e incluyó una incidencia del 4,8% de parálisis transitoria del nervio frénico

Introduction and objectives: Long-term efficacy following cryoballoon ablation of lone paroxysmal atrial fibrillation remains unknown. We describe long-term follow-up results of the single cryoballoon ablation procedure. Methods Pulmonary vein isolation was performed in 103 patients (72 male; median age 52 years) with symptomatic lone paroxysmal atrial fibrillation. The end-point of this observational cohort study was first electrocardiogram-documented recurrence of arrhythmia (atrial fibrillation, atrial tachycardia, or atrial flutter) during the 5-year follow-up, in the absence of anti-arrhythmic treatment. Results Acute complete pulmonary vein isolation was achieved in 86% of the patients with a single cryoballoon. The 6-month, 1-year, and 5-year success rate after a single procedure was 94%, 91%, and 77%, respectively. Arrhythmia recurrence was observed in 24 cases at a median of 14.8 months [range, 8.0-16.8 months]. Thirteen symptomatic patients were well controlled on beta-blockers only. Seven symptomatic patients had anti-arrhythmic treatment (class IC in 5 patients; dronedarone in 2 patients) introduced during the blanking period. Two of them had early arrhythmia recurrence within the blanking period only; they were arrhythmia-free in further follow-up on dronedarone. The rate of complications was relatively low and included a 4.8% incidence of transient phrenic nerve palsy. Conclusions A single cryoballoon ablation procedure for lone paroxysmal atrial fibrillation resulted in high rates of acute, medium-term, and long-term efficacy. The rate of complications is relatively low and includes a 4.8% incidence of transient phrenic nerve palsy incidence of transient phrenic nerve palsy

Cryoballoon ablation in young patients with lone paroxysmal atrial fibrillation.

INTRODUCTION AND OBJECTIVES: Long-term efficacy following cryoballoon ablation of lone paroxysmal atrial fibrillation remains unknown. We describe long-term follow-up results of the single cryoballoon ablation procedure. METHODS: Pulmonary vein isolation was performed in 103 patients (72 male; median age 52 years) with symptomatic lone paroxysmal atrial fibrillation. The end-point of this observational cohort study was first electrocardiogram-documented recurrence of arrhythmia (atrial fibrillation, atrial tachycardia, or atrial flutter) during the 5-year follow-up, in the absence of anti-arrhythmic treatment. RESULTS: Acute complete pulmonary vein isolation was achieved in 86% of the patients with a single cryoballoon. The 6-month, 1-year, and 5-year success rate after a single procedure was 94%, 91%, and 77%, respectively. Arrhythmia recurrence was observed in 24 cases at a median of 14.8 months [range, 8.0-16.8 months]. Thirteen symptomatic patients were well controlled on beta-blockers only. Seven symptomatic patients had anti-arrhythmic treatment (class IC in 5 patients; dronedarone in 2 patients) introduced during the blanking period. Two of them had early arrhythmia recurrence within the blanking period only; they were arrhythmia-free in further follow-up on dronedarone. The rate of complications was relatively low and included a 4.8% incidence of transient phrenic nerve palsy. CONCLUSIONS: A single cryoballoon ablation procedure for lone paroxysmal atrial fibrillation resulted in high rates of acute, medium-term, and long-term efficacy. The rate of complications is relatively low and includes a 4.8% incidence of transient phrenic nerve palsy.

Learning curve in cryoballoon ablation of atrial fibrillation: eight-year experience.

BACKGROUND: We analyzed the procedural experience cryoballoon ablation (CBA) of atrial fibrillation (AF) gained over 8 years in a high-volume centre to understand the influence of the learning curve on feasibility, safety and clinical outcome. METHODS AND RESULTS: In 424 patients (62% male) with drug-refractory AF, CBA was performed between 2005 and 2012. The analyzed period was divided into 8 calendar years. The endpoint of the study was arrhythmia recurrence after the 3-month blanking period in the 1-year follow-up since the index procedure, in the absence of anti-arrhythmic drugs class I and III. A combined AF type, Left Atrium size, Renal insufficiency, MEtabolic syndrome, cardiomyopathy (ALARMEc) risk score was calculated for each patient. The overall 1-year success rate of a single CBA was 73%. Continuous increase in 1-year success rate was observed with successive years of the study. The gradual improvement in outcome was related to gradual fall in ALARMEc risk score in successive patients. A continuous decrease in fluoroscopy and procedure time was observed in each subsequent year. CONCLUSIONS: CBA, followed by the proper selection of patients, facilitates a satisfactory outcome, especially in patients at an early stage of PV-trigger-dependent AF. Still, as with each new technology, it requires completion of a learning curve.

Score associated with the outcome after multiple ablation procedures in patients with atrial fibrillation.

BACKGROUND: Catheter ablation (CA) of atrial fibrillation (AF) is now established therapeutic option. Multiple procedures (MPs) are often needed to achieve the satisfactory outcome. The aim of the study was to assess the outcome after MPs in AF patients categorized to risk-score groups. METHODS: We followed a cohort of consecutive 911 (69% male; median 59 years) patients with AF (58% paroxysmal) who had CAAF performed. ALARMEC (Atrial fibrillation type, Left Atrium size, Renal insufficiency, MEtabolic syndrome, cardiomyopathy) risk score was calculated for each patient. The end point was maintenance of sinus rhythm at the follow-up of 60 months. RESULTS: We performed 1,199 CAAF procedures. One, two, and three procedures were performed in 663 (73%), 208 (23%), and 40 (4%) patients, respectively. Outcome after the first procedure (56%) was improved with MPs (76%). MPs > 2 were performed in 1%, 3%, 5%, 6%, and 10% patients with ALARMEC score of 0, 1, 2, 3, and 4, respectively. MPs were successful in 89%, 86%, 81%, 65%, and 43% of patients with ALARMEC score of 0, 1, 2, 3, and 4, respectively. Outcome in 174 (19%) patients on antiarrhythmic drugs (AADs) was 85%, 68%, 75%, 44%, and 39% in ALARMEC score: 0, 1, 2, 3, and 4, respectively. Outcome in 737 (81%) patients without AAD was 90%, 85%, 80%, 77%, and 69% in ALARMEC score of 0, 1, 2, 3, and 4, respectively. CONCLUSION: The moderate success rate after index procedure of CAAF can be further improved with multiple ones and AAD.

Ipsilateral circumferential radiofrequency ablation of atrial fibrillation with irrigated tip catheter: long-term outcome and pre-procedural predictors.

BACKGROUND: Predictors of long-term outcome of atrial fibrillation (AF) ablation are unknown. The predictors of 5-year follow-up (FU) after single ipsilateral circumferential antrum pulmonary vein isolation (PVI) with irrigated tip catheter were investigated. METHODS AND RESULTS: In 356 patients (74% male) with AF (44% paroxysmal AF [PAF]) PVI was performed. Success was defined as absence of AF, atrial flutter or tachycardia (AFLAT) recurrence. A total of 161 patients (45%) were free of AFLAT. The univariate predictors of AFLAT recurrence were: type of AF (non-PAF vs. PAF, P=0.0001), size of LA (normalized left atrium area [NLA] ≥11.5 vs. NLA <11.5, P=0.0001), renal function (glomerular filtration rate [GFR] <68ml/min vs. GFR ≥68ml/min, P=0.001) and hypertension (HT vs. no HT, P=0.025). The independent predictors of AFLAT-free survival were non-PAF (hazard ratio [HR], 1.67; 95% confidence interval [CI]: 1.23-2.26, P=0.0005), NLA ≥11.5 (HR, 1.40; 95% CI: 1.03-1.90, P=0.007) and GFR <68ml/min (HR, 1.70; 95% CI: 1.21-2.37, P=0.008). CONCLUSIONS: Single PVI results in a moderate success rate in patients with AF during 5-year FU without the use of a 3-D mapping system. Higher success was observed in patients with PAF, non-enlarged LA and good renal function.

Repeated catheter ablation of atrial fibrillation: how to predict outcome?

BACKGROUND: Pre-procedural predictors (PP) of atrial fibrillation (AF) recurrence (AFR) after repeated catheter ablation of AF (RCAF) are unknown. The aim of this study was identification of PP of outcome after RCAF. METHODS AND RESULTS: In 213 patients (73% male) with drug-refractory AF (47% paroxysmal AF; PAF) RCAF was performed. CHADS2, CHA2DS2-VASc and ALARMEc (AF type, Left Atrium size, Renal insufficiency, MEtabolic syndrome, cardiomyopathy) scores were calculated for each patient. Complete success was defined as no AFR. After RCAF, 125 patients (59%) were free of atrial flutter or atrial tachycardia (AFLAT) on long-term follow-up (FU). The univariate predictors of AFR were: type of AF (non-PAF vs. PAF, P=0.001), normalized left atrium area (NLA ≥10.25 vs. NLA <10.25, P=0.012) and estimated glomerular filtration rate (<68ml/min vs. ≥68ml/min, P=0.048). The independent predictors of AFLAT-free survival after RCAF were non-PAF (P=0.002) and NLA ≥10.25 (P=0.018). Among combined predictors, only ALARMEc score, and neither CHADS2 or CHA2DS2-VASc, predicted outcome after RCAF (P<0.0001). CONCLUSIONS: RCAF results in a moderate success rate on very long-term FU. Lower success was observed in patients with non-PAF and enlarged LA. ALARMEc score allows for clear description of expected outcome after RCAF.

Cryoballoon ablation of paroxysmal atrial fibrillation: 5-year outcome after single procedure and predictors of success.

AIMS: Long-term efficacy following cryoballoon (CB) ablation of atrial fibrillation (AF) remains unknown. This study describes 5 years follow-up results and predictors of success of CB ablation in patients with paroxysmal atrial fibrillation (PAF). METHODS AND RESULTS: In total, 163 patients were enrolled with symptomatic, drug refractory PAF. Pulmonary vein isolation (PVI) with CB technique was performed. Primary endpoint of this consecutive single-centre study was first electrocardiogram-documented recurrence of AF, atrial tachycardia or atrial flutter (AFLAT). Five years success rate after single CB ablation was 53%. In 70% of the patients acute complete PVI was achieved with a single 28 mm balloon. The univariate predictors of AFLAT recurrence were (1) size of left atrium, with normalized left atrium (NLA) ≥10.25 [hazard ratios (HR) of 1.81, 95% confidence interval (CI): 1.28-2.56] when compared with NLA <10.25 (35% vs. 53%, P = 0.0001) and (2) renal function, with impaired glomerular filtration rate (GFR) <80 ml/min (HR of 1.26, 95% CI: 1.02-1.57) when compared with GFR ≥80 ml/min (45% vs. 53%, P = 0.041). Normalized left atrium ≥10.25 was the sole independent predictor for outcome (HR 2.11; 95% CI: 1.34-3.31; P = 0.0001). CONCLUSIONS: Sinus rhythm can be maintained in a substantial proportion of patients with PAF even 5 years after circumferential PVI using CB ablation. The rate of decline in freedom from AFLAT was highest within the first 12 months after the index procedure. The patients with enlarged left atrium and/or impaired renal function have lower outcome.

Differences in clinical and echocardiographic parameters between paroxysmal and persistent atrial flutter in the AURUM 8 study: targets for prevention of persistent arrhythmia?

PURPOSE: Cavotricuspid isthmus-dependent atrial flutter (AFL) can occur in a paroxysmal or persistent pattern. The aim of this study was to identify clinical, echocardiographic, and electrophysiological risk factors independently associated with persistence of AFL. METHODS: Patients of the recently published AURUM 8 study with paroxysmal versus persistent AFL were compared with respect to clinical and echocardiographic baseline characteristics as well as procedural parameters. The AURUM 8 study is a randomized, multicenter clinical trial comparing the efficacy and safety of gold versus platinum-iridium 8-mm-tip ablation. AFL was paroxysmal in 218 patients and persistent in 210 patients. RESULTS: Univariate analysis revealed that patients with persistent AFL had higher New York Heart Association class (P = 0.002), shorter time since 1st AFL episode (median 0.18 vs 0.34, P = 0.037), a higher prevalence of previous coronary artery bypass grafting surgery (17% vs 9%, P = 0.02), left ventricular hypertrophy (17% vs 8%, P = 0.005), dyspnea during AFL (P < 0.001), mitral regurgitation (P = 0.002), tricuspid regurgitation (P = 0.049), and pulmonary hypertension (P = 0.01). Palpitations during AFL were less frequent in patients with persistent AFL (P = 0.001). Multivariate analysis revealed that age, weight, AFL diagnosis after initiation of class IC or III antiarrhythmic drugs for atrial fibrillation, history of left ventricular hypertrophy, dyspnea during AFL and mitral regurgitation on echocardiography were significant independent variables associated with persistent AFL. A history of atrial fibrillation and palpitations during AFL were independently associated with paroxysmal AFL. CONCLUSIONS: We were able to identify clinical and echocardiographic risk factors associated with persistence of typical AFL. Treatment of these risk factors can potentially not only prevent the transition from paroxysmal to persistent AFL, but maybe also the development or initiation of AFL in general.

Catheter ablation of stable ventricular tachycardia before defibrillator implantation in patients with coronary heart disease (VTACH): an on-treatment analysis.

BACKGROUND: In the Ventricular Tachycardia Ablation in Coronary Heart Disease (VTACH) study, an intention-to-treat approach was used and may have diminished the observed degree of treatment effect. We present a subanalysis of the VTACH study by treatment actually received. METHODS AND RESULTS: The VTACH study was a prospective, open, randomized controlled trial, undertaken in 16 European centers, comparing defibrillator implantation with and without ventricular tachycardia (VT) ablation in patients with stable VT, previous myocardial infarction, and reduced left-ventricular ejection fraction. Of the 52 patients in the ablation group, 7 (13%) did not receive VT ablation and 19% of patients assigned to implantable cardioverter defibrillator (ICD) only treatment group crossed over and had an ablation. The primary endpoint (first recurrence of any documented VT or ventricular fibrillation [VF]) was reached after a median of 19.5 months in the ablation group and 5.9 months in the ICD only group (P = 0.01). Overall, 685 VT/VF events occurred per year of follow-up in 22 patients of the ablation group and 4,986 events in 43 patients of the control group (P = 0.024). In the ICD only group, median numbers of VT/VF episodes were 25 (IQR 5.8-45.3) and 1.5 (IQR 0-24.8) per patient and year before and after crossover (n = 12), respectively. CONCLUSION: On-treatment analysis of the VTACH study emphasizes the effectiveness of VT ablation in patients receiving ICD treatment because of monomorphic VT post myocardial infarction. VT ablation clearly prolonged time to recurrence of VT/VF episodes and markedly decreased VT/VF burden.

Major determinants of myocardial injury after pulmonary vein isolation with radiofrequency ablation.

BACKGROUND: Radiofrequency (RF) current is used as a common energy source to perform pulmonary vein isolation (PVI) in patients with atrial fibrillation. We applied measurements of the blood concentration of cTnI as a surrogate parameter for the injured cell mass. AIM: To clarify which parameters are major determinants of myocardial injury, estimated by cTnI, after PVI with RF ablation. METHODS: The study population consisted of 82 consecutive patients in whom PVI with RF ablation was performed. In 41 patients, additional linear lesions (LL) were needed. Blood samples were obtained during venous puncture before a procedure and a further one, six and 24 hours after ablation. RESULTS: Pathological cTnI values were observed in all patients in the first hour and further increased in time. The median of peak cTnI value in the LL group was significantly (p 〈 0.05) higher than the respective value in patients without LL made: 1.16 (0.85;1.98) and 0.94 (0.65;1.14) ng/mL, respectively. Significantly higher cTnI values (p = 0.043) were observed in patients who maintained sinus rhythm in long term follow-up. CONCLUSIONS: The only independent predictor of myocardial injury after PVI with RF ablation, expressed as an increase in cTnI level, is cumulative energy applied. The larger the myocardial injury, the greater the PVI effectiveness.

Impact of impaired renal function and metabolic syndrome on the recurrence of atrial fibrillation after catheter ablation: a long term follow-up.

BACKGROUND: The goal of this study was to analyze impact of metabolic syndrome (MetS) and impaired renal function on long-term follow-up after catheter ablation of atrial fibrillation (AF). METHODS AND RESULTS: A total of 702 consecutive patients with AF (age = 58 year, history of AF = 5 year, male = 478, paroxysmal atrial fibrillation = 416, coronary artery disease = 62, hypertension = 487) considered for catheter ablation were enrolled in the study. The MetS was diagnosed at admission in 276 patients. The renal function was estimated by glomerular filtration rate (eGFR). Pulmonary vein isolation (PVI) was performed either with cryoballoon technique (n = 260) or circumferential PVI (n = 442) with a 3.5-mm irrigated tip catheter. A 7-day-Holter electrocardiogram was performed at each follow-up visit. Any episode of documented AF after an initial 3-month blanking period was considered as clinical endpoint. Out of 702 patients, 370 (52.7%) were free of AF recurrences at median follow-up of 15 six interquartile range (12.7-42.3) months. The patients with MetS had significantly lower success rate than those without (128/276 (46.4%) vs 242/426 (56.8%), P = 0.006). Among 103 patients with eGFR < 68 mL/min only 35 (34%) were free of recurrences compared with 335/599 (55.9%) in patients with GFR ≥ 68 mL/min (P = 0.001). Both parameters were revealed in multivariate analysis to be independent predictors for outcome after catheter ablation. CONCLUSION: The results of our study clearly demonstrated that outcome after 1st catheter ablation of AF is poor in patients with MetS and/or impaired renal function. This observation has a potential clinical impact for the follow up management of these patients.

Which standard biomarkers are useful for the evaluation of myocardial injury after pulmonary vein isolation with cryoballoon?

BACKGROUND: Many studies have used creatinine kinase (CK), myocardial bound for CK (CK-MB), and cardiac troponin I (cTnI) and T (cTnT) to evaluate myocardial cells injury after ablation. We applied measurements of the blood concentration of cardio-specific biomarkers as surrogates for the injured cell mass. AIM: To clarify which of the standard biomarkers are useful in the evaluation and quantification of lesions produced by cryoballoon ablation (CBA) during pulmonary vein isolation. METHODS: The CBA was performed in 33 patients with atrial fibrillation. Blood samples were obtained before CBA and one, six, and 24 h after CBA. We analysed CK, CK-MB and cTnI. RESULTS: A significant increase of all biomarkers was observed at each hour of collection as compared to the baseline measurement. Maximum median peak levels occurred at 6 h. Pathological values of CK, CK-MB and cTnI were observed in 94%, 100% and 100% of patients, respectively. Both maximum CK and CK-MB values correlated with median temperature (p < 0.05) reached during CBA. Additionally, CK-MB correlated with total cryo-time (p < 0.03). CONCLUSIONS: The CK-MB is the best biochemical marker for the evaluation of myocardial injury after CBA. The cTnI can be useful as an additional parameter of myocardial injury after CBA.

Effectiveness of Cardiac Resynchronization Therapy by QRS Morphology in the Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy (MADIT-CRT).

BACKGROUND: This study aimed to determine whether QRS morphology identifies patients who benefit from cardiac resynchronization therapy with a defibrillator (CRT-D) and whether it influences the risk of primary and secondary end points in patients enrolled in the Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy (MADIT-CRT) trial. METHODS AND RESULTS: Baseline 12-lead ECGs were evaluated with regard to QRS morphology. Heart failure event or death was the primary end point of the trial. Death, heart failure event, ventricular tachycardia, and ventricular fibrillation were secondary end points. Among 1817 patients with available sinus rhythm ECGs at baseline, there were 1281 (70%) with left bundle-branch block (LBBB), 228 (13%) with right bundle-branch block, and 308 (17%) with nonspecific intraventricular conduction disturbances. The latter 2 groups were defined as non-LBBB groups. Hazard ratios for the primary end point for comparisons of CRT-D patients versus patients who only received an implantable cardioverter defibrillator (ICD) were significantly (P < 0.001) lower in LBBB patients (0.47; P < 0.001) than in non-LBBB patients (1.24; P = 0.257). The risk of ventricular tachycardia, ventricular fibrillation, or death was decreased significantly in CRT-D patients with LBBB but not in non-LBBB patients. Echocardiographic parameters showed significantly (P < 0.001) greater reduction in left ventricular volumes and increase in ejection fraction with CRT-D in LBBB than in non-LBBB patients. CONCLUSIONS: Heart failure patients with New York Heart Association class I or II and ejection fraction ≤ 30% and LBBB derive substantial clinical benefit from CRT-D: a reduction in heart failure progression and a reduction in the risk of ventricular tachyarrhythmias. No clinical benefit was observed in patients with a non-LBBB QRS pattern (right bundle-branch block or intraventricular conduction disturbances). CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00180271.