Early recurrences after atrial fibrillation ablation: prognostic value and effect of early reablation

Very early recurrence predicts long-term outcome in patients after atrial fibrillation catheter ablation: a prospective study

Background

Long-term recurrence (LR) is a tendency that re-occurs within 3 months after catheter ablation for atrial fibrillation (AF). Whether very early recurrence (VER) within 7 days of post ablation is a prognostic factor of LR or not is unclear. For this reason, present study sought to examine the relationship between VER and LR.

Methods

In this prospective analysis 378 consecutive patients underwent an initial catheter ablation for paroxysmal or persistent AF. The association between VER and LR was analyzed by univariate and multivariate Cox regression, as well as time-dependent receiver operator characteristic (ROC) analysis.

Results

After a mean follow-up of 14.71 ± 8.58 months, 81 (65.90%) patients with VER experienced LR and were associated with lower event of free survival from LR (Log rank test, P < 0.001). Multivariate Cox regression analysis revealed that VER (HR = 7.02, 95% CI = 4.78–10.31; P < 0.001), left atrial enlargement (HR = 2.92, 95% CI = 1.88–4.54; P < 0.001), tendency in advanced age (HR = 1.50, 95% CI = 0.99–2.28; P = 0.054), and tendency in male (HR = 0.71, 95% CI = 0.50–1.01; P = 0.060) were independent predictors of LR. According to time-dependent ROC analysis, it was found that VER was more sensitive than common risk factors in predicting LR (0.74 vs 0.66, P < 0.001) and combination model further improved the C statistic for predicting LR (0.82 vs 0.66, P < 0.001).

Conclusions

After a single procedure of catheter ablation, patients with VER were strongly associated with LR and combination of VER and common risk factors could further improve prediction of patients who were at high risk for LR.

Pulmonary Vein Re-Isolation as a Routine Strategy Regardless of Symptoms: The PRESSURE Randomized Controlled Trial

OBJECTIVES

The goal of this study was to determine whether a strategy of early re-isolation of pulmonary vein (PV) reconnection in all patients, regardless of symptoms, would reduce the recurrence of atrial fibrillation (AF) and improve quality of life.

BACKGROUND

Lasting pulmonary vein isolation (PVI) remains elusive. PV reconnection is strongly linked to the recurrence of arrhythmia.

METHODS

A total of 80 patients with paroxysmal AF were randomized 1:1 after contact force-guided PVI to receive either standard care or undergo a repeat electrophysiology study after 2 months regardless of symptoms (repeat study). At the initial procedure, PVI was demonstrated by entrance/exit block and adenosine administration after a minimum 20-min wait. At the repeat study, all sites of PV reconnection were re-ablated. Patients recorded electrocardiograms daily and whenever symptomatic for 12 months using a handheld monitor. Recurrence was defined as ≥30 s of atrial tachyarrhythmia (AT) after a 3-month blanking period. The Atrial Fibrillation Effect on Quality-of-Life Questionnaire was completed at baseline and at 6 and 12 months.

RESULTS

All 40 patients randomized to repeat study attended for this after 62 ± 6 days, of whom 25 (62.5%) had reconnection of 41 (26%) PVs. There were no complications related to these procedures. Subjects recorded a total of 32,203 electrocardiograms (380 [335 to 447] per patient) during 12.6 (12.2 to 13.2) months of follow-up. AT recurrence was significantly lower for the repeat study group (17.5% vs. 42.5%; p = 0.03), as was AT burden (p = 0.03). Scores on the Atrial Fibrillation Effect on Quality-of-Life Questionnaire were higher in the repeat study group at 6 months (p < 0.001) and 12 months (p = 0.02).

CONCLUSIONS

A strategy of routine repeat assessment with re-isolation of PV reconnection improved freedom from AT recurrence, AT burden, and quality of life compared with current standard care. (The Effect of Early Repeat Atrial Fibrillation [AF] on AF Recurrence [PRESSURE]; NCT01942408).

What's Old is New Again - A Review of the Current Evidence of Colchicine in Cardiovascular Medicine

Colchicine is a well-established drug approved by the Food and Drug Administration (FDA) for the prevention and treatment of gout. It possesses unique anti-inflammatory properties. Interests in the usage of colchicine in cardiovascular medicine have been rekindled recently with several large trials been carried out to investigate its efficacy in treatment of various cardiac conditions including pericarditis, postpericardiotomy syndrome, atrial fibrillation and coronary artery disease. In this review, the basic pharmacological properties of colchicine will be discussed, and the evidences of its benefits for different applications in cardiovascular medicine will be reviewed.

What Does The Blanking Period Blank?

In the management of paroxysmal, drug-refractory atrial fibrillation, pulmonary vein isolation has become a widely accepted treatment option. Currently, the arrhythmias following any form of myocardial ablation are not considered within a period of three months, known as "the blanking period". Although this period is authority- rather than evidence-based, it has become universally recognized. Indeed, several mechanisms play a role to determine the transient increased risk of post-procedural atrial tachyarrhythmias, occurring early after the procedure. Acute inflammatory changes may be responsible for immediate recurrence, since application of ablative energy on atrial tissue has a pro-inflammatory- and potentially arrhythmogenic effect. Atrial arrhythmias within the first 3 months after ablation are very common (35% to 65% of cases) and their significance as predictor of late recurrences is more significant during the first month. Furthermore, the current biological evidences indicate that the edema of the surrounding and ablated tissue is no longer present after 1 month. In our letter we advocate the reasons why a blanking period of four weeks should appear more reasonable, fostering its clinical importance and utility.

Mechanisms and clinical significance of early recurrences of atrial arrhythmias after catheter ablation for atrial fibrillation

Early recurrence of atrial arrhythmias (ERAA) after ablation is common and strongly predicts late recurrences and ablation failure. However, since arrhythmia may eventually resolve in up to half of patients with ERAA, guidelines do not recommend immediate reintervention for ERAA episodes occurring during a 3-mo post-ablation blanking period. Certain clinical demographic, electrophysiologic, procedural, and ERAA-related characteristics may predict a higher likelihood of long-term ablation failure. In this review, we aim to discuss potential mechanisms of ERAA, and to summarize the clinical significance, prognostic implications, and treatment options for ERAA.

Effect and Significance of Early Reablation for the Treatment of Early Recurrence of Atrial Fibrillation After Catheter Ablation

There are few reports on early reablation (ER) for early recurrence of atrial fibrillation (AF) after catheter ablation. The present study evaluated the efficacy and significance of ER for early recurrence within a blanking period of 3 months after ablation of both paroxysmal and persistent AF, using a propensity-matched analysis. Of 874 patients who underwent catheter ablation of AF, 389 (45%) had early recurrence. Of these, 78 patients underwent an ER procedure. A total of 132 matched patients (66 in the ER and 66 in the non-ER groups, 82 patients with paroxysmal AF) were included in the analysis. During a mean follow-up of 15.4 months, the patients who underwent ER had a significantly lower recurrence rate than those who did not (29 [44%] vs 42 patients [64%], p = 0.023). The benefit of ER was especially apparent in patients with paroxysmal AF (p = 0.008) but not in those with persistent AF (p = 0.774). However, 24 patients (36%) in the non-ER group did not experience recurrence after a blanking period without any reablation procedure. The total number of reablation sessions was higher in the ER group than in the non-ER group (1.2 ± 0.5 vs 0.4 ± 0.6, p <0.001). Nonetheless, mean number of arrhythmia outpatient clinic visits at follow-up was significantly fewer in the ER group than in the late reablation group. In conclusion, ER for early recurrence of AF after catheter ablation might be effective for preventing recurrence during follow-up, especially for paroxysmal AF.

Value of Implantable Loop Recorders in Monitoring Efficacy of Radiofrequency Catheter Ablation in Atrial Fibrillation

BACKGROUND The aim of this study was to evaluate the value of the implantable loop recorder (ILR) in diagnosing atrial fibrillation (AF) and assessing the postoperative efficacy of radiofrequency catheter ablation (RFCA). MATERIAL AND METHODS A total of 32 patients who successfully underwent RFCA were selected. These patients discontinued antiarrhythmic medication with no AF recurrence for more than 3 months after RFCA, and underwent ILR placement by a conventional method. The clinical manifestations and information on arrhythmias recorded by the ILR were followed up to assess the efficacy of AF RFCA. RESULTS The mean follow-up period was 24.7±12.5 months. Of 32 patients with ILR information, 27 had successful RFCA and 5 had recurrent AF. The follow-up results obtained by traditional methods showed 29 patients with successful RFCA and 3 with recurrent AF (P<0.05). Among the 18 patients with clinical symptoms, 13 had recorded cardiac arrhythmic events (72.2%) and 5 showed sinus rhythm (27.8%). The ILRs recorded 18 patients with arrhythmic events (56.3%), including 12 cases of atrial arrhythmias, among whom 5 recurred at 9, 12, 16, 17, and 32 months after AF RFCA; there were also 2 patients with ventricular tachycardia (VT) and 4 with bradycardia. CONCLUSIONS The value of ILR in assessing the efficacy of AF RFCA was superior to that of traditional methods. ILR can promptly detect asymptomatic AF, and can monitor electrocardiogram features after RFCA, thus providing objective evidence of efficacy.

Trends and predictors of repeat catheter ablation for atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) ablation is superior to pharmacologic therapy in achieving maintenance of normal sinus rhythm in selected patient populations. However, the procedure is resource intensive, and repeat ablations are sometimes required. We examined the predictors and trends of repeat ablation using a large national administrative claims database.

METHODS

Privately insured and Medicare Advantage patients who underwent catheter ablation for AF between January 1, 2004, and September 30, 2014, were included in the study. The primary outcome was repeat AF ablation during enrollment. We examined the associations between repeat ablation and patient demographics (age, gender, socioeconomic demographics), comorbid conditions (CHA2DS2-Vasc score and Charlson index), and year of the index ablation. Cox proportional hazard models were used to identify predictors of repeat ablation.

RESULTS

We included 8,648 adult patients in the analysis. Median age was 61.0 (interquartile range [IQR] 54-68) years, and 70.9% were men. Median follow-up was 1.1 (IQR 0.5-2.3) years. A total of 1,263 patients underwent repeat ablation (14.6%) over a total of 14,280 person-years (12.1% at 1 year). The hazard ratio (HR) for repeat ablation was higher in younger patients (HR 0.75 [0.61-0.91; P < .01] for age 65-75 and 0.55 [0.4-0.75; P < .001] for age ≥ 75 compared with age 18-54), those with higher household income (HR 1.24 [1-1.54; P < .05] for household income ≥ $100,000 compared with household income < $40,000), patients treated in the south (HR 1.15 [1-1.31]; P < .05), and those on antiarrhythmic medications (HR 1.15 [1.01-1.31]; P < .05). In particular, younger patients (ages 18-54 years) continued to undergo repeat ablations over the entire follow-up period, and the cumulative rate was approximately 40% among those followed for 5 years. Clinical characteristics including those included in the CHA2DS2-Vasc score and Charlson index did not predict likelihood of repeat ablation. The rate of repeat ablation remained constant over the available follow-up.

CONCLUSION

Approximately 1 in 8 patients treated with catheter ablation for AF will undergo a second procedure within 1 year, although the rate is as high as 40% in young patients at 5 years. The rate of repeat ablation appears to be associated with demographic characteristics (younger age and higher household income) rather than medical comorbidities.

Electrophysiological Perspectives on Hybrid Ablation of Atrial Fibrillation

To overcome limitations of minimally invasive surgical ablation as a standalone procedure in eliminating atrial fibrillation (AF), hybrid approaches incorporating adjunctive endovascular catheter ablation have been proposed in recent years. The endovascular component targets residual conduction gaps and identifies additional electrophysiological targets with the goal of minimizing recurrent atrial arrhythmia. We performed a systematic review of published studies of hybrid AF ablation, analyzing 432 pooled patients (19% paroxysmal, 29% persistent, 52% long-standing persistent) treated using three different approaches: A. bilateral thoracoscopy with bipolar radiofrequency (RF) clamp-based approach; B. right thoracoscopic suction monopolar RF catheter-based approach; and C. subxiphoid posterior pericardioscopic ("convergent") approach. Freedom from recurrence off antiarrhythmic medications at 12 months was seen in 88.1% [133/151] for A, 73.4% [47/64] for B, and 59.3% [80/135] for C, with no significant difference between paroxysmal (76.9%) and persistent/long-standing persistent AF (73.4%). Death and major surgical complications were reported in 8.5% with A, 0% with B and 8.6% with C. A critical appraisal of hybrid ablation is presented, drawing from experiences and insights published over the years on catheter ablation of AF, with a discussion of the rationale underlying hybrid ablation, its strengths and limitations, where it may have a unique role in clinical management of patients with AF, which questions remain unanswered and areas for further investigation.

Second-generation cryoballoon ablation for paroxysmal atrial fibrillation: Predictive role of atrial arrhythmias occurring in the blanking period on the incidence of late recurrences

BACKGROUND

Although consensus documents on catheter and surgical ablation of atrial fibrillation (AF) suggest a uniform "blanking period" of 3 months, recent evidence suggested that early recurrences of atrial tachyarrhythmias (ERATs) are strongly associated with late recurrences (LRs), especially if ERATs occurred in the last part of the "blanking period".

OBJECTIVE

The present study sought to assess the role of ERATs in predicting LRs in a large cohort of patients with paroxysmal AF who have undergone second-generation cryoballoon ablation.

METHODS

Consecutive patients with drug-resistant paroxysmal AF who underwent pulmonary vein isolation using CB-A technology as the index procedure were retrospectively included in our analysis. The exclusion criteria were any contraindications for the procedure, including the presence of an intracavitary thrombus, uncontrolled heart failure, contraindications to general anesthesia, and persistent AF.

RESULTS

A total of 331 consecutive patients (104 women [31%]; mean age 56.7 ± 13.3 years) were enrolled. Atrial tachyarrhythmias/AF recurrences were detected in 57 patients (17.2%). The highest prevalence of ERATs was observed in the first 2 weeks (55%) after pulmonary vein isolation. Of note, all the ERATs occurring 1.5 months after AF ablation relapsed after 3 months and were confirmed as definitive recurrences. Late recurrence of AF and atrial tachycardia occurred in 20 of 29 patients with ERATs (69.0%) and 28 of 302 patients without ERATs (9.3%) (P < .0001). A multivariate Cox regression analysis showed that the early recurrence within the blanking period was significantly and independently associated with an increased risk of developing a late recurrence (hazard ratio 6.79; 95% confidence interval 3.52-10.14; P < .0001).

CONCLUSION

Our findings reveal that ERATs are strongly associated with an LR after paroxysmal AF ablation using CB-A technology (hazard ratio 6.79; 95% confidence interval 3.52-10.14; P < .0001). Of note, when ERATs occurred later than 1.5 months, patients systematically experienced an LR.

An atrial fibrosis-based approach for atrial fibrillation ablation

Since the emergence of atrial fibrillation (AF) ablation as a reliable method of restoring sinus rhythm, various approaches have been used to improve the efficacy while maximizing the safety of ablation. A major hurdle to optimizing outcomes for AF ablation has been the failure to recognize that the substrate of the individual patient plays a significant role in optimizing AF treatment. Using delayed-enhancement MRI for the detection of left atrial fibrosis, our group has been able to correlate these structural remodeling changes to outcomes of stroke, AF recurrence and congestive heart failure. This has provided us with information to optimize care of our AF patients based on screening for a fibrotic atrial cardiomyopathy, for which AF is the arrhythmic manifestation. By employing an MRI-guided approach for AF ablation, we have been able to optimize AF management and enhance the delivery of personalized medicine for our patients.

Early recurrence of atrial arrhythmias following pulmonary vein antral isolation: Timing and frequency of early recurrences predicts long-term ablation success

BACKGROUND

Early recurrence of atrial arrhythmia (ERAA) is common after atrial fibrillation (AF) ablation and is associated with long-term recurrence. However, the association between timing or frequency of ERAA and long-term ablation success remains unclear.

OBJECTIVE

We aimed to examine whether timing or frequency of ERAA after pulmonary vein antral isolation (PVAI) affects long-term ablation success.

METHODS

Three hundred AF patients (100 paroxysmal, 100 persistent, 100 long-standing persistent; mean age 59.5 ± 9.6 years, 79% male) undergoing PVAI were included. All patients underwent 30-day monitoring with mobile continuous outpatient telemetry after PVAI and were followed for >1 year. ERAA was defined as AF or organized atrial tachycardia (OAT) in the first 6 weeks, and was categorized as early (weeks 1-2), intermediate (weeks 3-4), or late (weeks 5-6). Long-term ablation success was defined as the absence of AF/OAT lasting >30 seconds off antiarrhythmic drugs 1 year after a single ablation (excluding first 6 weeks).

RESULTS

ERAA occurred in 169 patients (53%); of those, 79 (46.7%) had single ERAA and 90 (53.3%) had multiple ERAAs. ERAA occurred less commonly with paroxysmal versus persistent or long-standing persistent AF (46% vs 57% and 66%; P = .017). ERAA was associated with worse ablation success at 1 year (38.1% vs 79.5% [no ERAA]; P < .001). Multiple (vs single) ERAA more strongly predicted long-term ablation failure (OR: 4.5; 95% CI [2.3-8.8]).

CONCLUSIONS

ERAA after PVAI is associated with decreased long-term ablation success. Patients experiencing multiple ERAA events are at greatest risk for long-term arrhythmia recurrence and represent a subgroup in whom early reablation may be considered.

The Impact of Left Atrial Surface Area and the Second Generation Cryoballoon on Clinical Outcome of Atrial Fibrillation Cryoablation

AIMS

In this observational study, we examine the significance of the left atrial (LA) surface area and compare the clinical usage of the Arctic Front Advance (CBA) versus Arctic Front (CB) cryoballoon with the intent to investigate the impact of each in terms of long-term freedom from atrial fibrillation (AF) for patients with nonvalvular AF.

METHODS

Pulmonary vein isolation (PVI) was performed while using a cryoballoon ablation catheter in conjunction with an intraluminal circular diagnostic mapping catheter, Achieve. The consecutive patients ablated with CBA were matched with patients previously ablated with CB, using propensity score matching. The primary endpoint of this observational single-center retrospective study was the first observation of electrocardiogram-documented recurrence of atrial arrhythmias lasting >30 seconds.

RESULTS

The patient demographic data were similar in the CBA- and CB-group (N = 188 patients each group). In all patients in the CBA-group and in 95% of the patients in the CB group, acute procedural PVI of all veins was achieved with the single usage of a 28-mm cryoballoon. The one-year freedom from atrial arrhythmias was significantly better in the CBA- versus the CB-group of patients, 90% versus 64%, respectively. During 15-month clinical follow-up in CBA group, patients with LA area above 23 cm(2) were more likely to experience recurrence of AF (23%) than patients with LA area below 23 cm(2) (7%).

CONCLUSIONS

Comparing one-year outcomes, the CBA is superior to the CB with regards to maintenance of normal sinus rhythm. When using the CBA catheter, an enlarged LA is associated with a higher recurrence of arrhythmia.

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.

Recurrence of atrial fibrillation within three months after pulmonary vein isolation for patients with paroxysmal atrial fibrillation: Analysis using external loop recorder with auto-trigger function

BACKGROUND

Pulmonary vein isolation (PVI) via catheter ablation has been shown to be a highly effective treatment option for patients with symptomatic paroxysmal atrial fibrillation (AF). The recurrence of AF within 3 months after PVI is not considered to be the result of ablation procedure failure, because early recurrence of AF is not always associated with late recurrence. We examined the usefulness of an external loop recorder with an auto-trigger function (ELR-AUTO) for the detection of atrial fibrillation following PVI to characterize early recurrence and to determine the implications of AF occurrence within 3 months after PVI.

METHODS

Fifty-three consecutive symptomatic patients with paroxysmal AF (age 61.6±12.6 years, 77% male) who underwent PVI and were fitted with ELR-AUTO for 7±2.0 days within 3 months after PVI were enrolled in this study.

RESULTS

Of the 33 (62.2%) patients who did not have AF recurrence within 3 months after PVI, only 1 patient experienced AF recurrence at 12 months. Seven (35%) of the 20 patients who experienced AF within 3 months of PVI experienced symptomatic AF recurrence at 12 months. The sensitivity, specificity, positive predictive value, and negative predictive value of early AF recurrence for late recurrence were 87.5%, 71.1%, 35.0%, and 96.9%, respectively.

CONCLUSIONS

AF recurrence measured by ELR-AUTO within 3 months after PVI can predict the late recurrence of AF. Freedom from AF in the first 3 months following ablation significantly predicts long-term AF freedom. ELR-AUTO is useful for the detection of symptomatic and asymptomatic AF.

The predictive value of echocardiographic parameters associated with left ventricular diastolic dysfunction on short- and long-term outcomes of catheter ablation of atrial fibrillation

AIMS

Recurrence of atrial fibrillation (AF) is frequently observed after AF catheter ablation. However, the predictive value of echocardiographic parameters associated with left ventricular diastolic dysfunction (LVDD) has not been well studied.

METHODS AND RESULTS

In 124 consecutive patients (mean age 61 ± 10 years, 60% male) with paroxysmal (n = 70) or persistent AF (n = 54) undergoing AF catheter ablation, mitral early diastolic peak (E-wave) and late peak (A-wave) velocities, E/A ratio, deceleration time (DT) of mitral early velocity, early diastolic mitral annulus peak velocity (e'), and E/e' ratio were determined by transthoracic echocardiography. Early (ERAF) and late AF recurrence (LRAF) were monitored with 7-day Holter electrocardiograms directly after catheter ablation and after 6 and 12 months. Early AF recurrence occurred in 34% of the patients, while LRAF was observed in 27% of the patients. Patients with ERAF had higher E-wave (0.9 ± 0.2 vs. 0.8 ± 0.2 m/s, P = 0.035) and lower A-wave velocity (0.5 ± 0.2 vs. 0.6 ± 0.2 m/s, P = 0.038), higher E/A ratio (1.8 ± 0.9 vs. 1.5 ± 0.9, P = 0.089), and slower DT (214 ± 67 vs. 243 ± 68 ms, P = 0.073), while E/e', left atrial diameter, and left ventricular ejection fraction were similar. In multivariable regression analysis, the E/A ratio was the only independent predictor of ERAF (odds ratio 2.905, 95% confidence interval 1.072-7.870, P = 0.036). None of the echocardiographic parameters influenced the late therapy outcome.

CONCLUSION

Early results of the catheter ablation, but not the late rhythm outcome, are influenced by an impaired mitral inflow pattern, which is associated with LVDD.

Monitoring Atrial Fibrillation After Catheter Ablation

Although catheter ablation is an effective treatment for recurrent atrial fibrillation (AF), there is no consensus on the definition of success or follow-up strategies. Symptoms are the major motivation for undergoing catheter ablation in patients with AF, however it is well known that reliance on perception of AF by patients after AF ablation results in an underestimation of recurrence of the arrhythmia. Because symptoms of AF occurrence may be misleading, a reliable assessment of rhythm outcome is essential for the definition of success in both clinical care and research trials. Continuous rhythm monitoring over long periods of time is superior to intermittent recording using external monitors to detect the presence of AF episodes and to quantify the AF burden. Today, new devices implanted subcutaneously using a minimally invasive technique have been developed for continuous AF monitoring. Implantable devices keep detailed information about arrhythmia recurrences and might allow identification of very brief episodes of AF, the significance of which is still uncertain. In particular, it is not known whether there is any critical value of daily AF burden that has a prognostic significance. This issue remains an area of active discussion, debate and investigation. Further investigation is required to determine if continuous AF monitoring with implantable devices is effective in reducing stroke risk and facilitating maintenance of sinus rhythm after AF ablation.

Colchicine for prevention of atrial fibrillation recurrence after pulmonary vein isolation: mid-term efficacy and effect on quality of life

BACKGROUND

Our group previously showed that colchicine treatment is associated with decreased early recurrence rate after ablation for atrial fibrillation (AF).

OBJECTIVE

The purpose of this study was to test the mid-term efficacy of colchicine in reducing AF recurrences after a single procedure of pulmonary vein isolation in patients with paroxysmal AF. Assessment of quality-of-life (QOL) changes was a secondary objective.

METHODS

Patients with paroxysmal AF who were scheduled for ablation were randomized to a 3-month course of colchicine 0.5 mg twice daily or placebo and were followed for a median of 15 months (with a 3-month blanking period). QOL was assessed with a general-purpose health-related QOL tool (26-item World Health Organization QOL questionnaire) at baseline and after 3 and 12 months.

RESULTS

Two hundred twenty-three randomized patients underwent ablation, and 206 patients were available for analysis (144 male, age 62.2 ± 5.8 years). AF recurrence rate in the colchicine group was 31.1% (32/103) vs 49.5% (51/103) in the control group (P = .010), translated in a relative risk reduction of 37% (odds ratio 0.46, 95% confidence interval 0.26-0.81). The number needed to treat was 6 (95% confidence interval 3.2-19.8). Physical domain QOL scores at 12 months were 63.6 ± 13.8 in the colchicine group and 52.5 ± 18.1 in controls, whereas psychological domain scores were 56.1 ± 13.7 vs 44.7 ± 17.3, respectively (P <.001, for both).

CONCLUSION

Colchicine treatment after pulmonary vein isolation for paroxysmal AF is associated with lower AF recurrence rates after a single procedure. This reduction is accompanied by corresponding improvements in physical and psychological health-related QOL scores.

Incidence and significance of early recurrences of atrial fibrillation after cryoballoon ablation: insights from the multicenter Sustained Treatment of Paroxysmal Atrial Fibrillation (STOP AF) Trial

BACKGROUND

Early recurrence of atrial fibrillation (ERAF) is common after radiofrequency catheter ablation for AF. We sought to determine the incidence and prognostic significance of ERAF after cryoballoon ablation. Moreover, the benefit of early reablation for ERAF after cryoballoon ablation is undetermined.

METHODS AND RESULTS

The Sustained Treatment of Paroxysmal Atrial Fibrillation (STOP AF) trial randomized 245 patients with paroxysmal AF to medical therapy versus cryoballoon-based pulmonary vein ablation. Patients were followed for 12 months. ERAF was defined as any recurrence of AF >30 seconds during the first 3 months of follow-up. Late recurrence (LR) was defined as any recurrence of AF >30 seconds between 3 and 12 months. Of the 163 patients randomized to cryoablation, 84 patients experienced ERAF (51.5%). The only significant factor associated with ERAF was male sex (hazard ratio [HR], 2.18; 95% confidence interval [CI], 1.03-4.61; P=0.041). LR was observed in 41 patients (25.1%), and was significantly related to ERAF (55.6% LR with ERAF versus 12.7% without ERAF; P<0.001). Among patients with ERAF, only current tobacco use (HR, 3.84; 95% CI, 1.82-8.11; P<0.001) was associated with LR. Conversely, early reablation was associated with greater freedom from LR (3.3% LR with early reablation versus 55.6% without; HR, 0.04; 95% CI, 0.01-0.32; P=0.002).

CONCLUSIONS

ERAF after cryoballoon ablation occurs in ≈50% of patients and is strongly associated with LR. Early reablation for ERAF is associated with excellent long-term freedom from recurrent AF.

Which are the most reliable predictors of recurrence of atrial fibrillation after transcatheter ablation?: a meta-analysis

CONTEXT

Transcatheter ablation of atrial fibrillation (AF) has undergone important development, with acceptable midterm results in terms of the safety and recurrence. A meta-analysis was performed to identify the periprocedural complications, midterm success rates and predictors of recurrence after AF ablation.

METHODS AND RESULTS

4357 patients with paroxysmal AF, 1083 with persistent AF and 1777 with long standing AF were included. The pooled analysis showed that there was an in-hospital complication rate of tamponade requiring drainage of 0.99% (0.44-1.54; CI 99%), stroke with neurological persistent impairment of 0.22% (0.04-0.47; CI 99%), and stroke without of 0.36% (0.03-0.70; CI 99%) After a follow up of 22 (13-28) months and 1.23 (1.19-1.5; CI 99%) procedures per patient, the AF recurrence rate was 31.20% (24.87-34.81; CI 99%). The persistent AF patients exhibited a greater risk of recurrence after the first ablation (OR 1.78 [1.14, 2.77] CI 99%), but a trend towards non significance was present in the patients with more than one procedure (OR 1.69 [0.95, 3.00] CI 99%). The most powerful predictors of an AF ablation failure in the overall population were a recurrence within 30-days (OR 4.30; 2.00-10.80), valvular AF (OR 5.20; 2.22-9.50) and a left atrium diameter of more than 50mm (OR 5.10 2.00-12.90; all CI 95%).

CONCLUSIONS

Persistent AF remains burdened from higher recurrence rates, however not so following redo-procedures. Three predictors, valvular AF, a left atrium diameter longer than 50mm and recurrence within 30 days, could be appraised to drive selection of patients and therapeutic strategy.

Association between C-reactive protein and atrial fibrillation recurrence after catheter ablation: a meta-analysis

BACKGROUND

Atrial fibrillation (AF) is associated with inflammation. Increased serum C-reactive protein (CRP) levels are important representatives of an inflammatory state of AF. A variety of studies have evaluated whether increased CRP levels have an association with AF recurrence after catheter ablation. However, the results remain inconsistent, therefore, this meta-analysis was conducted to offer suggestions.

HYPOTHESIS

Increased baseline CRP have an association with AF recurrence after catheter ablation.

METHODS

Electronic databases including PubMed, Embase, Medline, ISI Web of Knowledge, and ScienceDirect were searched until December 31, 2012 for any CRP-associated studies. Overall and subgroup analyses were performed. Standardized mean difference (SMD) and 95% confidence interval (CI) were used to evaluate the associations between CRP levels and postablation AF recurrence. Statistical analysis was performed with Review Manager 5.2 and Stata 11.0.

RESULTS

Seven available studies were identified, which included 526 patients (179 recurrence vs 347 no recurrence). Overall, increased baseline CRP levels had significant positive association with postablation AF recurrence. The SMD in the CRP levels was 0.65 units (95% CI: 0.30-0.99), and the z-score for overall effect was 3.70 (P = 0.0002). The heterogeneity test showed that there were moderate differences between individual studies (P = 0.006, I(2) = 67%). Metaregression revealed that different sample sizes of studies possibly accounted for the heterogeneity. Positive associations were also found in subgroup analyses based on sample size. When stratifying for ethnicity, similarly significant associations were found in both European (Caucasian) and Asian populations.

CONCLUSIONS

Investigations demonstrate that baseline CRP levels are greater in patients with postablation AF recurrence. Further studies with larger sample size and delicate design for CRP should be conducted.

Conduction recovery in patients with recurrent atrial fibrillation after pulmonary vein isolation using multi-electrode duty cycled radiofrequency ablation

INTRODUCTION

The pulmonary vein ablation catheter (PVAC) is designed for pulmonary vein isolation (PVI). Electrical reconnection of pulmonary veins is believed to result in AF recurrence. The purpose of this study was to establish the location and extent of PV reconnection after PVI with the PVAC catheter.

METHODS AND RESULTS

Eighty-two patients (79 % male, age 60 ± 9 years) that underwent a redo procedure for recurrent AF after PVAC ablation were assessed for prevalence and location of reconnection. The number of reconnected PV's was 0, 1, 2, 3, or 4 in 2 (2.4 %), 14 (17 %), 23 (28 %), 28 (34 %), and 15 (18 %) patients, respectively. Reconnection of left superior, left inferior, left common, right superior, and right inferior PV's was found in 66, 63, 83, 57, and 67 %, respectively (p = 0.48). In the left PV's, reconnection was located significantly more anterior than posterior; LSPV anterior 32/70 vs posterior 13/70 (p < 0.01), LIPV anterior 26/70 vs posterior 9/70 (p < 0.01). In the right PV's reconnection was distributed equally in all quadrants. Different modes of RF delivery during PVAC ablation (bipolar/unipolar 2:1 [n = 35] vs. 4:1 [n = 47]) yielded comparable rates of PV reconnection. During follow-up (median 296 days) no AF/AT was documented in 57 patients (70 %).

CONCLUSION

Almost all patients (98 %) with AF after PVAC ablation show reconnection of at least one PV. All PV's are equally likely to show reconnection. In the left PV's, reconnection was found more often anteriorly than posteriorly. During pulmonary vein isolation with the PVAC catheter, prevalent sites of reconnection deserve close attention to increase success.

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.

Adenosine testing after cryoballoon pulmonary vein isolation improves long-term clinical outcome

BACKGROUND

Adenosine infusion after pulmonary vein isolation (PVI) with radiofrequency energy reveals dormant muscular sleeves and predicts atrial fibrillation (AF) recurrence. The aim of our study was to determine whether adenosine could reveal dormant PV sleeves after cryoballoon isolation and study its effect on long-term recurrence of AF.

METHODS

Patients with paroxysmal AF underwent cryoballoon PVI. After PVI, adenosine 25 mg was infused to test for dormant muscular sleeves in each vein. If reconnection under adenosine was shown, further cryoballoon ablation was performed until no more reconnection occurred. Follow-up was performed with ECG, 24-h Holter recording, and a symptom questionnaire at three monthly intervals. Transtelephonic Holter monitoring was performed for 1 month before and 3 months after PVI. Patients who underwent cryoballoon PVI without adenosine administration were used as controls for comparison.

RESULTS

In the study group (n = 34, 24 males), adenosine revealed dormant sleeves in 9/132 (8 %) veins, and 7/34 (21 %) patients. All but one vein was further treated until the dormant sleeves were isolated. During a mean follow-up of 520 ± 147 days, 23/34 (68 %) patients were free of AF without antiarrhythmic drugs (AADs). In the control group (n = 65, 46 males), 29/65 (46 %) were free of AF without AADs. There were significantly less AF recurrences in the study group (p = 0.04).

CONCLUSIONS

Adenosine administration after cryoballoon PVI reveals dormant muscular sleeves in 21 % of patients. Clinical follow-up shows that adenosine testing is effective in reducing AF recurrence after cryoballoon ablation.

Predictors of Recurrence After Radiofrequency Ablation of Persistent Atrial Fibrillation

Radiofrequency catheter ablation that targets the pulmonary veins is well established as a mainstay for drug-refractory, paroxysmal atrial fibrillation (AF). However, in patients with persistent AF, the ideal approach remains elusive. Further, despite the various additional ablation strategies that have been investigated in patients with persistent AF, the rate of recurrent atrial tachyarrhythmias after ablation remains relatively high. In this review, the predictors of recurrent atrial tachyarrhythmias after catheter ablation of persistent AF will be discussed.

Use of an Implantable Monitor to Detect Arrhythmia Recurrences and Select Patients for Early Repeat Catheter Ablation for Atrial Fibrillation

Background—

Catheter ablation of atrial fibrillation (AF) has proved effective in curing highly symptomatic patients with paroxysmal AF. The aim of this prospective, randomized study was to identify the optimal treatment of patients with AF recurrences after the first ablation.

Methods and Results—

Two hundred eighty-six patients with paroxysmal AF underwent ablation (circumferential pulmonary vein isolation with linear lesions) and were monitored with an implantable cardiac monitor (Reveal XT, Medtronic). Patients without AF recurrences during the 3-month postablation period were assigned to group 1; those with AF recurrences to group 2. Patients in group 2 were randomly assigned to group 3 or group 4. Group 3 patients were treated only with antiarrhythmic drugs for 6 weeks, with no early reablation during the 3-month postablation period. In the case of AF recurrence after the 3-month postablation period, patients underwent reablation. Group 4 patients were treated according to the onset mechanism of AF recurrences, as detected and stored by the implantable cardiac monitor: antiarrhythmic drug therapy, but no reablation if AF was not preceded by triggers; early reablation if premature atrial beats or atrial tachycardias or flutter triggered AF. All patients were followed up for 1 year to assess maintenance of sinus rhythm in each group. On 12-month follow-up examination, of the 119 (42%) patients in group 1, 112 (94%) had no AF recurrences. Among the 83 patients in group 3, only 27 (33%) had no recurrences. Of the 84 group 4 patients, 67 (80%) had no AF recurrences ( P <0.0001 versus group 3).

Conclusions—

Patients with recurrences after the first AF ablation are likely to respond to a second early ablation when AF is triggered by supraventricular arrhythmias or premature contractions.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT01164319.

Clinical significance of early recurrences of atrial tachycardia after atrial fibrillation ablation

BACKGROUND

atrial tachycardia (AT) commonly recurs within 3 months after radiofrequency catheter ablation for atrial fibrillation (AF). However, it remains unclear whether early recurrence of atrial tachycardia (ERAT) predicts late recurrence of AF or AT.

METHODS

of 352 consecutive patients who underwent circumferential pulmonary vein isolation with or without linear ablation(s) for AF, 56 patients (15.9%) with ERAT were identified by retrospective analysis. ERAT was defined as early relapse of AT within a 3-month blanking period after ablation.

RESULTS

during 21.7 ± 12.5 months, the rate of late recurrence was higher in patients with ERAT (41.1%) compared with those without ERAT (11.8%, P < 0.001). In a multivariable model, positive inducibility of AF or AT immediately after ablation (65.2% vs 36.4%, P = 0.046; odd ratio, 3.9; 95% confidence interval, 1.0-14.6) and the number of patients who underwent cavotricuspid isthmus (CTI) ablation (73.9% vs 42.4%, P = 0.042; odd ratio, 4.5; 95% confidence interval, 1.1-19.5) were significantly related to late recurrence in the ERAT group. The duration of ablation (174.3 ± 62.3 vs 114.7 ± 39.5 minutes, P = 0.046) and the procedure time (329.3 ± 83.4 vs 279.2 ± 79.7 minutes, P = 0.027) were significantly longer in patients with late recurrence than in those without late recurrence following ERAT.

CONCLUSIONS

the late recurrence rate is higher in the patients with ERAT compared with those without ERAT following AF ablation, and is more often noted in the patients who underwent CTI ablation and had a prolonged procedure time. Furthermore, inducibility of AF or AT immediately after ablation independently predicts late recurrence in patients with ERAT.

Early recurrence of atrial tachyarrhythmias following radiofrequency catheter ablation of atrial fibrillation

The use of blanking periods, the immediate period postablation during which transient tachyarrhythmia episodes are not considered recurrences, has been predicated on the assumption that not all early recurrences of atrial tachyarrhythmias (ERAT) will lead to later recurrences and, as such, does not necessarily represent treatment failure. While ERAT can be expected to occur in approximately 38% of patients within the first 3 months of atrial fibrillation (AF) ablation, only half of these patients will manifest later recurrences. Clinical features related to the patient's history of AF, the index ablation procedure, and particularities of the ERAT can help identify patients at higher risk of later recurrence in whom aggressive attempts to control rhythm, including early cardioversion and reintervention, may be justified.

Acute pericardial effusion following atrial fibrillation ablation: characteristics and relationship with arrhythmia recurrences

BACKGROUND

Pericardial effusion (PE) can occur during or after atrial fibrillation (AF) ablation, and may induce atrial arrhythmia.

AIM

To characterize the impact of PE on arrhythmia recurrences following AF ablation.

METHODS

Patients referred for a first radiofrequency AF ablation were studied prospectively. Transthoracic echocardiography was performed before and 24h after the procedure. If PE was present, transthoracic echocardiography was repeated at 1 month to evaluate PE evolution. Early arrhythmia recurrences (EARs) were defined as any arrhythmia documented within 1 month of the procedure.

RESULTS

PE was diagnosed in 18/81 patients (22%); and was present in significantly more patients with persistent versus paroxysmal AF (14/40 [35%] vs 4/41 [10%]; P=0.008). PEs were mild (mean 6 ± 3mm), mainly asymptomatic (89%), and none required pericardiocentesis. Early and late arrhythmia recurrences were present in 25/81 (31%) and 29/81 (36%), respectively. The incidence of PE was significantly higher among patients with EARs versus those without (12/25 [48%] vs 6/56 [11%]; P=0.0004). By multivariable analysis, PE and duration in AF were the two independent predictors of EARs. PE incidence was similar in patients with and without late arrhythmia recurrences. At 1 month, no patients had PE on transthoracic echocardiography.

CONCLUSION

PE following radiofrequency AF ablation is frequent, particularly following persistent AF ablation. This effusion is generally mild, mainly asymptomatic, and independently associated with EARs.

Characteristics and significance of very early recurrence of atrial fibrillation after catheter ablation

INTRODUCTION

Early restoration of sinus rhythm following ablation of atrial fibrillation (AF) facilitates reverse atrial remodeling and improves the long-term outcome. The purpose of this study was to determine the predictors and outcome in patients with very early AF recurrences (< 2 days).

METHODS AND RESULTS

Ablation was performed in 339 consecutive AF patients (paroxysmal AF = 262). Biatrial voltage was mapped during sinus rhythm. If recurrent AF occurred within 2 days following the ablation, electrical cardioversion was performed to restore sinus rhythm. Very early recurrences of AF occurred in 39 (15%) patients with paroxysmal AF and 26 (34%) with nonparoxysmal AF. Patients with very early recurrence had a higher incidence of nonparoxysmal AF (40% vs 18.6%, P< 0.001), requirement of electrical cardioversion during procedure, larger left atrial (LA) diameter (43 ± 7 vs 39 ± 6 mm, P< 0.001), lower left ventricular ejection fraction (54 ± 10% vs 59 ± 7, P< 0.001), longer procedural time, and lower LA voltage (1.5 ± 0.7 vs 1.9 ± 0.8 mV, P< 0.001). A multivariate analysis revealed that the independent predictors of a very early recurrence were a longer procedural time and lower LA voltage. During a follow-up of 13 ± 5 months, a very early recurrence did not predict the long-term outcome of a single procedure recurrence in the patients with paroxysmal AF, but was associated with a late recurrence in the nonparoxysmal AF patients.

CONCLUSION

Very early recurrence occurred in patients with paroxysmal AF is not associated with long-term recurrence. Nonparoxysmal AF is an independent predictor of late recurrence of AF in patients with very early recurrence.