Catheter Ablation for Atrial Fibrillation on Uninterrupted Warfarin: Can It Be Done Without Echo Guidance?

Effect of uninterrupted dabigatran or rivaroxaban on achieving ideal activated clotting time to heparin response during catheter ablation in patients with atrial fibrillation

BACKGROUND

Uninterrupted use of oral anticoagulants before atrial fibrillation (AF) ablation can reduce the incidence of perioperative thromboembolic events. However, the effect of new oral anticoagulants on activated clotting time (ACT) in response to heparin during AF ablation in Chinese populations remains unknown. The aim of the present retrospective study was to investigate the value of ACTs in response to intraoperative heparin administration in patients using dabigatran or rivaroxaban.

METHODS

From January 2018 to December 2021, a total of 173 patients undergoing AF ablation were included in the study, in which 101 patients were treated with dabigatran, 72 patients were treated with rivaroxaban. The intraoperative ACT values were examined in both groups. The incidence of periprocedural complications was evaluated.

RESULTS

Initial heparin dosage (88 ± 19 U/kg vs. 78 ± 27 U/kg, P < 0.05), total heparin dosage (137 ± 41 U/kg vs. 106 ± 52 U/kg, P < 0.05) during the ablation procedure were higher in the dabigatran group than those in the rivaroxaban group. Mean ACT (280 ± 36 s vs. 265 ± 30 s, P < 0.05), and the percentage of ACTs within the therapeutic range (250-350 s) (74% ± 26% vs. 60% ± 29%, P < 0.05) were significantly lower in the dabigatran group than those in the rivaroxaban group, particularly in male patients. Furthermore, the average time of achieving the target ACT (250-350 s) was also found longer in the dabigatran group (P < 0.05) as compared with the rivaroxaban group. No significant difference was found in the incidence of periprocedural complications between the two groups.

CONCLUSIONS

The anticoagulant effect of uninterrupted rivaroxaban therapy appears to be more stable and efficient than dabigatran administration during catheter ablation in patients with AF.

Efficacy of statins combined with amiodarone in the treatment of atrial fibrillation: A meta-analysis

Objectives:

Atrial fibrillation (AF) is a common arrhythmia in clinics with a high mortality rate. Recently, statins combined with amiodarone and amiodarone alone were used in the treatment of AF. This systematic review study aims to investigate the clinical efficacy and usefulness of statins combined with amiodarone and amiodarone alone in treating AF.

Methods:

Pubmed, Embase, Web of Science, Medline, Cochrane Library, and China National Knowledge Infrastructure were used to search for the relevant studies and full-text articles involved in evaluating statin-amiodarone versus amiodarone alone for AF. All included articles were quality assessed, and the data analysis was conducted with Review Manager 5.4.

Results:

Eight (8) relevant studies with 758 AF patients were included in this analysis. In the Meta-analysis, Statin-amiodarone treatment reduced AF recurrence (RR, 0.61; 95% CI, 0.50–0.75; p < 0.00001), C-reactive protein (CRP) level (MD, 0.96; 95%CI, 0.64–1.29, p < 0.00001) and Left atrial diameter (LAD) (MD, 0.81; 95%CI, 0.06–1.56; p = 0.03) compared with amiodarone alone for AF. However, no difference was observed for change of total cholesterol (TC) (MD, 1.32; 95%CI, −0.24–2.88; p = 0.10).

Conclusion:

Statin-amiodarone effectively reduced CRP level, LAD and reduced the recurrence of AF than amiodarone alone.

Interrupted versus uninterrupted anticoagulation therapy for catheter ablation in adults with arrhythmias

BACKGROUND

The management of anticoagulation therapy around the time of catheter ablation (CA) procedure for adults with arrhythmia is critical and yet is variable in clinical practice. The ideal approach for safe and effective perioperative management should balance the risk of bleeding during uninterrupted anticoagulation while minimising the risk of thromboembolic events with interrupted therapy.

OBJECTIVES

To compare the efficacy and harms of interrupted versus uninterrupted anticoagulation therapy for catheter ablation (CA) in adults with arrhythmias.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, and SCI-Expanded on the Web of Science for randomised controlled trials on 5 January 2021. We also searched three registers on 29 May 2021 to identify ongoing or unpublished trials. We performed backward and forward searches on reference lists of included trials and other systematic reviews and contacted experts in the field. We applied no restrictions on language or publication status.

SELECTION CRITERIA

We included randomised controlled trials comparing uninterrupted anticoagulation with any modality of interruption with or without heparin bridging for CA in adults aged 18 years or older with arrhythmia.

DATA COLLECTION AND ANALYSIS

Two review authors conducted independent screening, data extraction, and assessment of risk of bias. A third review author resolved disagreements. We extracted data on study population, interruption strategy, ablation procedure, thromboembolic events (stroke or systemic embolism), major and minor bleeding, asymptomatic thromboembolic events, cardiovascular and all-cause mortality, quality of life (QoL), length of hospital stay, cost, and source of funding. We used GRADE to assess the certainty of the evidence.  MAIN RESULTS: We identified 12 studies (4714 participants) that compared uninterrupted periprocedural anticoagulation with interrupted anticoagulation. Studies performed an interruption strategy by either a complete interruption (one study) or by a minimal interruption (11 studies), of which a single-dose skipped strategy was used (nine studies) or two-dose skipped strategy (two studies), with or without heparin bridging. Studies included participants with a mean age of 65 years or greater, with only two studies conducted in relatively younger individuals (mean age less than 60 years). Paroxysmal atrial fibrillation (AF) was the primary type of AF in all studies, and seven studies included other types of AF (persistent and long-standing persistent). Most participants had CHADS2 or CHADS2-VASc demonstrating a low-moderate risk of stroke, with almost all participants having normal or mildly reduced renal function. Ablation source using radiofrequency energy was the most common (seven studies). Ten studies (2835 participants) were conducted in East Asian countries (Japan, China, and South Korea), while the remaining two studies were conducted in the USA. Eight studies were conducted in a single centre. Postablation follow-up was variable among studies at less than 30 days (three studies), 30 days (six studies), and more than 30 days postablation (three studies). Overall, the meta-analysis showed high uncertainty of the effect between the interrupted strategy compared to uninterrupted strategy on the primary outcomes of thromboembolic events (risk ratio (RR) 1.76, 95% confidence interval (CI) 0.33 to 9.46; I2 = 59%; 6 studies, 3468 participants; very low-certainty evidence). However, subgroup analysis showed that uninterrupted vitamin A antagonist (VKA) is associated with a lower risk of thromboembolic events without increasing the risk of bleeding. There is also uncertainty on the outcome of major bleeding events (RR 1.10, 95% CI 0.59 to 2.05; I2 = 6%; 10 studies, 4584 participants; low-certainty evidence). The uncertainty was also evident for the secondary outcomes of minor bleeding (RR 1.01, 95% CI 0.46 to 2.22; I2 = 87%; 9 studies, 3843 participants; very low-certainty evidence), all-cause mortality (RR 0.34, 95% CI 0.01 to 8.21; 442 participants; low-certainty evidence) and asymptomatic thromboembolic events (RR 1.45, 95% CI 0.85 to 2.47; I2 = 56%; 6 studies, 1268 participants; very low-certainty evidence). There was a lower risk of the composite endpoint of thromboembolic events (stroke, systemic embolism, major bleeding, and all-cause mortality) in the interrupted compared to uninterrupted arm (RR 0.23, 95% CI 0.07 to 0.81; 1 study, 442 participants; low-certainty evidence). In general, the low event rates, different comparator anticoagulants, and use of different ablation procedures may be the cause of imprecision and heterogeneity observed.

AUTHORS' CONCLUSIONS

This meta-analysis showed that the evidence is uncertain to inform the decision to either interrupt or continue anticoagulation therapy around CA procedure in adults with arrhythmia on outcomes of thromboembolic events, major and minor bleeding, all-cause mortality, asymptomatic thromboembolic events, and a composite endpoint of thromboembolic events (stroke, systemic embolism, major bleeding, and all-cause mortality).  Most studies in the review adopted a minimal interruption strategy which has the advantage of reducing the risk of bleeding while maintaining a lower level of anticoagulation to prevent periprocedural thromboembolism, hence low event rates on the primary outcomes of thromboembolism and bleeding. The one study that adopted a complete interruption of VKA showed that uninterrupted VKA reduces the risk of thromboembolism without increasing the risk of bleeding. Hence, future trials with larger samples, tailored to a more generalisable population and using homogeneous periprocedural anticoagulant therapy and ablation source are required to address the safety and efficacy of the optimal management of anticoagulant therapy prior to ablation.

Uninterrupted Direct Oral Anticoagulants Without a Change in Regimen for Catheter Ablation for Atrial Fibrillation Is an Acceptable Protocol

Background: In patients undergoing catheter ablation (CA) for atrial fibrillation (AF), the use of uninterrupted direct oral anticoagulants (DOACs) is the current protocol. This study evaluated bleeding complications following the uninterrupted use of 4 DOACs in patients undergoing CA for AF without any change in the dosing regimen. Moreover, we assessed differences between once- and twice-daily DOAC dosing in patients undergoing CA for AF who continued on DOACs without any change in the dosing regimen.

Methods and Results: This study was a retrospective single-center cohort study of consecutive patients. All patients continued DOACs without interruption or changes to the dosing schedule, even in the case of morning procedures. The primary endpoint was the incidence of major bleeding events within the first 30 days after CA. In all, 710 consecutive patients were included in the study. Bleeding complications were less frequent in the uninterrupted twice- than once-daily DOACs group. However, the incidence of cardiac tamponade across all DOACs was low (0.98%; 7/710), suggesting that uninterrupted DOACs without changes to the dosing regimen may be an acceptable strategy. The rate of total bleeding events, including minor bleeding (12/710; 1.6%), was also satisfactory.

Conclusions: Uninterrupted DOACs without any change in dosing regimen for patients undergoing CA for AF is acceptable. Bleeding complications may be less frequent in patients receiving DOACs twice rather than once daily.

Heparin dosing in uninterrupted anticoagulation with dabigatran vs. warfarin in atrial fibrillation ablation: RE-CIRCUIT study

AIMS

To describe heparin dosing requirements in patients who underwent catheter ablation of atrial fibrillation with uninterrupted anticoagulation using dabigatran etexilate (dabigatran) or warfarin to attain therapeutic activated clotting time (ACT) in the RE-CIRCUIT® study. The RE-CIRCUIT study showed significantly fewer major bleeding events in the dabigatran vs. warfarin treatment group. Unfractionated heparin was administered during the procedure to maintain ACT >300 s.

METHODS AND RESULTS

Patients were randomly assigned to dabigatran 150 mg bid or international normalized ratio-adjusted warfarin. Ablation was performed with uninterrupted anticoagulation and continued for 8 weeks after the procedure. Heparin was administered after placement of femoral sheaths before or immediately after transseptal puncture. Ablation was performed in 635 patients (dabigatran, 317; warfarin, 318); data were available from 396 patients administered heparin (dabigatran, 191; warfarin, 205). Most frequent time window from last dose of study drug to septal puncture was 0 to <4 h in the dabigatran (41.3%) and 16 to <24 h in the warfarin arms (44.7%). Overall mean (standard deviation) heparin dose was similar between the dabigatran and warfarin groups [12 402 (10 721) vs. 11 910 (8359) IU, respectively]. Heparin dosing requirement to reach therapeutic ACT was lowest when time from last dose of dabigatran to septal puncture was 0 to <4 h.

CONCLUSION

Patients treated with dabigatran required a similar amount of unfractionated heparin as those treated with warfarin to achieve an ACT of >300 s during ablation. More heparin units were required when the time from the last dose of dabigatran to septal puncture increased.

Interrupted or Uninterrupted Oral Anticoagulants in Patients Undergoing Atrial Fibrillation Ablation

BACKGROUND AND PURPOSE

The safety and efficacy of uninterrupted, minimally interrupted (one dose skipped) or completely interrupted (24 h skipped) oral anticoagulant therapy in patients with atrial fibrillation (AF) ablation are poorly defined. We conducted a network meta-analysis to explore the effect of interrupted or uninterrupted oral anticoagulants in patients with AF undergoing ablation.

METHODS

The Cochrane Library, PubMed and Embase databases were systematically searched for studies comparing uninterrupted, minimally interrupted or completely interrupted non-vitamin K antagonist oral anticoagulants (NOACs) with continuous or interrupted warfarin in patients undergoing AF ablation.

RESULTS

Twelve randomized clinical trials (RCTs) with a total of 5597 patients with AF undergoing catheter ablation were included. For thromboembolism, minimally interrupted NOACs (OR 0.03, 95% CI 0.01-0.35), uninterrupted NOACs (OR 0.04, 95% CI 0.01-0.23) and continuous VKAs (OR 0.05, 95% CI 0.01-0.21) were better than interrupted warfarin. The risk of total bleeding appeared higher in the completely interrupted NOAC group compared with the minimally interrupted NOACs (OR 2.74, 95% CI 1.18-6.37), uninterrupted NOACs (OR 2.15, 95% CI 1.05-4.38) and uninterrupted warfarin (OR 2.04, 95% CI 1.02-4.08). To reduce the risk of total bleeding, minimally interrupted NOACs (OR 0.15, 95% CI 0.08-0.27), uninterrupted NOACs (OR 0.19, 95% CI 0.14-0.42) and uninterrupted warfarin (OR 0.24, 95% CI 0.15-0.39) were better than interrupted warfarin. In the event of major bleeding, there was no significant difference in the interrupted NOAC, uninterrupted NOAC, interrupted VKA and uninterrupted VKA groups.

CONCLUSIONS

These three NOAC strategies may have similar safety and efficacy in terms of thromboembolism and major bleeding complications. The total bleeding risk of completely interrupted oral anticoagulants is higher than that of uninterrupted and minimally interrupted NOACs. For thromboembolism, minimally interrupted NOACs, uninterrupted NOACs and continuous VKAs were better than interrupted warfarin.

Uninterrupted Dabigatran versus Warfarin for Ablation in Atrial Fibrillation

BACKGROUND

Catheter ablation of atrial fibrillation is typically performed with uninterrupted anticoagulation with warfarin or interrupted non-vitamin K antagonist oral anticoagulant therapy. Uninterrupted anticoagulation with a non-vitamin K antagonist oral anticoagulant, such as dabigatran, may be safer; however, controlled data are lacking. We investigated the safety of uninterrupted dabigatran versus warfarin in patients undergoing ablation of atrial fibrillation.

METHODS

In this randomized, open-label, multicenter, controlled trial with blinded adjudicated end-point assessments, we randomly assigned patients scheduled for catheter ablation of paroxysmal or persistent atrial fibrillation to receive either dabigatran (150 mg twice daily) or warfarin (target international normalized ratio, 2.0 to 3.0). Ablation was performed after 4 to 8 weeks of uninterrupted anticoagulation, which was continued during and for 8 weeks after ablation. The primary end point was the incidence of major bleeding events during and up to 8 weeks after ablation; secondary end points included thromboembolic and other bleeding events.

RESULTS

The trial enrolled 704 patients across 104 sites; 635 patients underwent ablation. Baseline characteristics were balanced between treatment groups. The incidence of major bleeding events during and up to 8 weeks after ablation was lower with dabigatran than with warfarin (5 patients [1.6%] vs. 22 patients [6.9%]; absolute risk difference, -5.3 percentage points; 95% confidence interval, -8.4 to -2.2; P<0.001). Dabigatran was associated with fewer periprocedural pericardial tamponades and groin hematomas than warfarin. The two treatment groups had a similar incidence of minor bleeding events. One thromboembolic event occurred in the warfarin group.

CONCLUSIONS

In patients undergoing ablation for atrial fibrillation, anticoagulation with uninterrupted dabigatran was associated with fewer bleeding complications than uninterrupted warfarin. (Funded by Boehringer Ingelheim; RE-CIRCUIT ClinicalTrials.gov number, NCT02348723 .).

Network meta-analysis of efficacy and safety of competitive oral anticoagulants in patients undergoing radiofrequency catheter ablation of atrial fibrillation

PURPOSE

The aim of this network meta-analysis was to evaluate the comparative efficacy and safety of dabigatran, rivaroxaban, apixaban, interrupted vitamin K antagonist (I-VKA), and continuous VKA (C-VKA) in patients undergoing radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF).

METHODS

PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials were searched to identify clinical trials comparing dabigatran, rivaroxaban, or apixaban with I-VKA or C-VKA, or against each other, in AF patients undergoing RFCA. A network meta-analysis was conducted to directly and indirectly compare the efficacy and safety of competitive anticoagulation regimens with a Bayesian random-effects model.

RESULTS

A total of 39 studies enrolling 27,766 patients were included. C-VKA demonstrated significant superiority over I-VKA in reducing thromboembolic events (risk difference [RD] -0.0068, 95 % confidence interval [CI] -0.0106 to -0.0032) and major bleeding complications (RD -0.0044, 95 % CI -0.0098 to -0.0006). Rivaroxaban compared with I-VKA was associated with a lower risk of thromboembolism (RD -0.0073, 95 % CI -0.0134 to -0.0012), being at the best ranking position among all of the compared anticoagulation regimens in terms of both the efficacy and safety. None of the remaining comparisons reached statistically significant difference in the rate of thromboembolism or major bleeding.

CONCLUSIONS

The present study suggests that C-VKA is superior to I-VKA for AF patients undergoing RFCA. Rivaroxaban is the highest probability to be the optimal alternative to C-VKA among the three non-VKA oral anticoagulants in AF ablation.

Atrial fibrillation and silent stroke: links, risks, and challenges

Atrial fibrillation (AF) is the most common cardiac arrhythmia, with a projected number of 1 million affected subjects in Germany. Changes in age structure of the Western population allow for the assumption that the number of concerned people is going to be doubled, maybe tripled, by the year 2050. Large epidemiological investigations showed that AF leads to a significant increase in mortality and morbidity. Approximately one-third of all strokes are caused by AF and, due to thromboembolic cause, these strokes are often more severe than those caused by other etiologies. Silent brain infarction is defined as the presence of cerebral infarction in the absence of corresponding clinical symptomatology. Progress in imaging technology simplifies diagnostic procedures of these lesions and leads to a large amount of diagnosed lesions, but there is still no final conclusion about frequency, risk factors, and clinical relevance of these infarctions. The prevalence of silent strokes in patients with AF is higher compared to patients without AF, and several studies reported high incidence rates of silent strokes after AF ablation procedures. While treatment strategies to prevent clinically apparent strokes in patients with AF are well investigated, the role of anticoagulatory treatment for prevention of silent infarctions is unclear. This paper summarizes developments in diagnosis of silent brain infarction and its context to AF.

Recurrence of atrial tachyarrhythmia during the second month of the blanking period is associated with more extensive pulmonary vein reconnection at repeat electrophysiology study

BACKGROUND

Current guidelines recommend a 3-month blanking period after pulmonary vein isolation (PVI) as early recurrence of atrial tachyarrhythmia (ERAT) may be due to transient proarrhythmic factors. However, studies have suggested that these factors resolve by 1 month. PV reconnection (PVrc) is strongly associated with postblanking AT recurrence in paroxysmal atrial fibrillation. We hypothesized that ERAT occurring beyond 4 weeks after PVI is associated with PVrc at repeat electrophysiology study.

METHODS AND RESULTS

Forty patients with paroxysmal atrial fibrillation underwent mandatory repeat electrophysiology study 2 months after PVI, regardless of symptoms, to document the number of reconnected PVs. Antiarrhythmic drugs, including β-blockers, were discontinued 4 weeks after PVI. Patients were instructed to record a 30-second ECG everyday between the 2 procedures using a portable monitor, with additional recordings for symptoms. ERAT was defined as ≥30 seconds of AT. Patients recorded a total of 3293 ECGs. Four (10%) patients had ERAT in the first 4 weeks (M1) only, 2 (5%) in month 2 (M2) only, and 11 (28%) in both. PVrc of 1 PV was identified in 12 (30%) patients and of >1 PV in 13 (32%) patients. ERAT in M2 was associated with PVrc, whereas M1 was not (11/13 [85%] versus 0/4 [0%]; P=0.006). M2 ERAT was strongly associated with PVrc of >1 PV (10/13 [77%] versus 3/27 [11%] without M2 ERAT; P<0.0001).

CONCLUSIONS

ERAT occurring beyond 4 weeks after PVI is associated with PVrc and particularly of PVrc of >1 PV. ERAT confined to M1 is unrelated to underlying PVrc. The relationship between ERAT beyond 4 weeks after PVI and postblanking AT recurrence merits further investigation.

Uninterrupted rivaroxaban vs. uninterrupted vitamin K antagonists for catheter ablation in non-valvular atrial fibrillation

Aims

VENTURE-AF is the first prospective randomized trial of uninterrupted rivaroxaban and vitamin K antagonists (VKAs) in patients with non-valvular atrial fibrillation (NVAF) undergoing catheter ablation (CA).

Methods and results

Trial size was administratively set at 250, the protocol-specified target. Events were independently and blindly adjudicated. We randomly assigned 248 NVAF patients to uninterrupted rivaroxaban (20 mg once-daily) or to an uninterrupted VKA prior to CA and for 4 weeks afterwards. The primary endpoint was major bleeding events after CA. Secondary endpoints included thromboembolic events (composite of stroke, systemic embolism, myocardial infarction, and vascular death) and other bleeding or procedure-attributable events. Patients were 59.5 ± 10 years of age, 71% male, 74% paroxysmal AF, and had a CHA2DS2-VASc score of 1.6. The average total heparin dose used to manage activated clotting time (ACT) was slightly higher (13 871 vs. 10 964 units; P < 0.001) and the mean ACT level attained slightly lower (302 vs. 332 s; P < 0.001) in rivaroxaban and VKA arms, respectively. The incidence of major bleeding was low (0.4%; 1 major bleeding event). Similarly, thromboembolic events were low (0.8%; 1 ischemic stroke and 1 vascular death). All events occurred in the VKA arm and all after CA. The number of any adjudicated events (26 vs. 25), any bleeding events (21 vs. 18), and any other procedure-attributable events (5 vs. 5) were similar.

Conclusion

In patients undergoing CA for AF, the use of uninterrupted oral rivaroxaban was feasible and event rates were similar to those for uninterrupted VKA therapy.

Name of the Trial Registry

Clinicaltrials.gov trial registration number is NCT01729871.

Peri-procedural interrupted oral anticoagulation for atrial fibrillation ablation: comparison of aspirin, warfarin, dabigatran, and rivaroxaban

Aims

Atrial fibrillation ablation requires peri-procedural oral anticoagulation (OAC) to prevent thromboembolic events. There are several options for OAC. We evaluate peri-procedural AF ablation complications using a variety of peri-procedural OACs.

Methods and results

We examined peri-procedural OAC and groin, bleeding, and thromboembolic complications for 2334 consecutive AF ablations using open irrigated-tip radiofrequency (RF) catheters. Pre-ablation OAC was warfarin in 1113 (47.7%), dabigatran 426 (18.3%), rivaroxaban 187 (8.0%), aspirin 472 (20.2%), and none 136 (5.8%). Oral anticoagulation was always interrupted and intraprocedural anticoagulation was unfractionated heparin (activated clotting time, ACT = 237 ± 26 s). Pre- and post-OAC drugs were the same for 1591 (68.2%) and were different for 743 (31.8%). Following ablation, 693 (29.7%) were treated with dabigatran and 291 (12.5%) were treated with rivaroxaban. There were no problems changing from one OAC pre-ablation to another post-ablation. Complications included 12 (0.51%) pericardial tamponades [no differences for dabigatran (P = 0.457) or rivaroxaban (P = 0.163) compared with warfarin], 12 (0.51%) groin complications [no differences for rivaroxaban (P = 0.709) and fewer for dabigatran (P = 0.041) compared with warfarin]. Only 5 of 2334 (0.21%) required blood transfusions. There were two strokes (0.086%) and no transient ischaemic attacks (TIAs) in the first 48 h post-ablation. Three additional strokes (0.13%), and two TIAs (0.086%) occurred from 48 h to 30 days. Only one stroke had a residual deficit. Compared with warfarin, the neurologic event rate was not different for dabigatran (P = 0.684) or rivaroxaban (P = 0.612).

Conclusion

Using interrupted OAC, low target intraprocedural ACT, and irrigated-tip RF, the rate of peri-procedural groin, haemorrhagic, and thromboembolic complications was extremely low. There were only minimal differences between OACs. Low-risk patients may remain on aspirin/no OAC pre-ablation. There are no problems changing from one OAC pre-ablation to another post-ablation.

Safety of Continuous Periprocedural Rivaroxaban for Patients Undergoing Left Atrial Catheter Ablation Procedures

Background—

This study aimed to evaluate the safety of continuous periprocedural rivaroxaban administration during left atrial radiofrequency ablation (RFA) in comparison with uninterrupted oral vitamin K antagonist administration. Data about the use of rivaroxaban in the setting of left atrial RFA procedures are lacking.

Methods and Results—

The study cohort included 544 patients (mean age, 63±10 years) who underwent left atrial RFA procedures between February 2012 and May 2013. All patients (n=272) receiving uninterrupted periprocedural rivaroxaban 15 or 20 mg/d before the procedure (rivaroxaban) were matched by age, sex, and type of rhythm disorder with an equal number of patients managed with uninterrupted vitamin K antagonist phenprocoumon (international normalized ratio, 2–3). During RFA, heparin was given intravenously to maintain an activated clotting time at 270 to 300 s. The safety end point was a composite of bleeding, thromboembolic events, and death. There were no thromboembolic complications and no deaths in either group. The prevalence of major bleeding complications was similar in both groups (1 tamponade in RivG and 1 groin hematoma requiring transfusion in phenprocoumon). Minor bleeding complications occurred equally in both groups (20 of 272; 7% in the rivaroxaban versus 33 of 272, 12% in the phenprocoumon; P =0.08). In multivariable analyses, female sex was associated with a greater risk of complications (odds ratio, 1.96; 95% confidence interval, 1.10–3.49).

Conclusions—

In patients undergoing left atrial RFA, continuous periprocedural rivaroxaban use seems to be as safe as uninterrupted periprocedural phenprocoumon administration.

The Safetyof Dabigatran Versus Warfarin in Patients Undergoing Atrial Fibrillation Ablation

The safety and optimal strategy of the use of dabigatran versus uninterrupted warfarin in atrial fibrillation ablation is currently unclear. We performed a retrospective analysis between July 2011-October 2012 of all patients undergoing an AF ablation who received uninterrupted warfarin therapy (199) and the routine cessation of Dabigatran therapy (126) 4 days pre-ablation. Major safety endpoints included: pericardial effusion (requiring pericardiocentesis), peripheral thromboembolism, CVA, and groin hematoma requiring blood transfusion. Minor endpoints included pericardial effusion and groin hematoma. Dabigatran was restarted the following day after ablation. The warfarin group was older, had a higher CHADS₂, CHA₂DS₂VASc and HASBLED scores and greater prevalence of aortic plaque. The major complication rate was 2.0% in the warfarin group and 2.4% in the dabigatran group (P= 0.83). The minor complication rate was 2.5% in the warfarin group and <1% in the dabigatran group (P= 0.27). In the dabigatran group, there was one renal thromboembolic event 4 days post-ablation. All patients in the warfarin group who suffered a major complication required a blood transfusion. Cessation of dabigatran therapy 4 days pre AF ablation has a comparable safety profile to uninterrupted warfarin therapy.

Optimal rhythm-control strategy for recurrent atrial tachycardia after catheter ablation of persistent atrial fibrillation: a randomized clinical trial

AIM

Although catheter ablation (CA) has replaced antiarrhythmic drugs (AAD) as first-line treatment in selected patients with atrial fibrillation (AF), optimal treatment of recurrent atrial tachycardia (AT) after AF ablation remains unclear. This parallel randomized controlled study compared CA vs. AAD for recurrent AT after persistent AF ablation.

METHODS AND RESULTS

Two-hundred and one patients (aged 59.1 ± 10.9 years, 68.7% male) with recurrent AT after persistent AF ablation were enrolled and randomized to either CA (n = 101) or AAD (n = 100) treatment. Primary endpoint was freedom from recurrent atrial tachyarrhythmia (ATa, including AT and AF) at 24-month follow-up. Composite secondary endpoints comprised procedural complications, long-term morbidity and improvement in quality of life (QoL). On an intention-to-treat basis, the CA group had a higher rate of freedom from recurrent ATa (56.4 vs. 34.0%; P = 0.001). Adjusted Cox regression analysis showed a significant treatment effect with a hazard ratio of 0.538 (95% CI: 0.355-0.816) in favour of CA. There was a higher proportion of periprocedural complications in the CA group (7.9 vs. 0; P = 0.012), and of long-term adverse events in the AAD group (10.9 vs. 24.0%; P = 0.014). Quality of life was significantly higher for CA.

CONCLUSIONS

This study demonstrates superiority of CA over AAD for recurrent AT after persistent AF ablation with regard to SR maintenance, long-term safety and QoL improvement. However, CA use might be limited by a higher risk for periprocedural complications.

The Prevalence of Low Left Atrial Appendage Emptying Velocity and Thrombus in Patients Undergoing Catheter Ablation for Atrial Fibrillation on Uninterrupted Peri-procedural Warfarin Therapy

Introduction: The 2012 HRS/EHRA/ECAS guidelines encourage pre-procedural transesophageal echocardiography (TEE) prior to ablation for atrial fibrillation (AF), but acknowledge a lack of consensus in patients maintained on therapeutic warfarin before, during and after the procedure. This is partly because the incidence of left atrial appendage (LAA) thrombus is so low, that it is hard to draw clear conclusion regarding the characteristics of patients who develop thrombus. We hypothesize that the presence of low LAA emptying velocities, which predisposes to thrombus, and/or thrombus itself can be predicted in patients undergoing ablation, based upon clinical characteristics and transthoracic echocardiography (TTE). Methods: In this multicentre study, we undertook TTE and transesophageal echocardiograms (TEE) in 586 patients (age 59.9±0.4 years old, 64.5% male) undergoing catheter ablation for AF who were anticoagulated on warfarin (target international normalized ratio 2-3.5) for ≥3 consecutive weeks prior to procedure and maintained on warfarin for the procedure. Results: Low peak LAA emptying velocities (<40cm/s) were identified in 111 (24.7%) patients and LAA thrombus was identified in 3 patients (0.5%) despite having therapeutic INRs. The 3 patients with thrombus had LAA emptying velocities of 23, 29 and 31 cm/s. None of the remaining patients had a peri-procedural stroke. Patients with peak LAA emptying velocities <40cm/s or thrombus on TEE had significantly (p<0.05) higher CHA₂DS₂-VASc scores (1.7± 0.1 v's 1.4±0.1), and were more likely to have impaired LVSF (odds ratio [95% CI]: 2.66 [1.52-4.66]), a LA diameter >4.6cm on TTE (2.40 [2.13-5.41]), or persistent AF (2.60 [1.63-4.14]) compared to those with a higher LAA velocity without thrombus. Conclusion: In patients on uninterrupted warfarin therapy, a CHA₂DS₂-VASc score ≥1 or LA diameter >4.6cm on TTE identifies 91.5% of those at risk of developing thrombus with LAA emptying velocity of <40 cm/s and 100% of those with thrombus in our cohort.

Resource Use and Cost Implications of Switching Among Warfarin Formulations in Atrial Fibrillation Patients

Background:

Despite the uncertainty surrounding the safety of switching warfarin formulations, limited data exist on the resource use and costs associated with this switching pattern.

Objective:

To evaluate health care resource use and costs associated with switching warfarin formulations among patients with atrial fibrillation (AF) in a managed care organization.

Methods:

Patients diagnosed with AF (ICD-9 427.31) between July 2004 and August 2008 and who received warfarin therapy were identified in the HealthCore Integrated Research Database and categorized into 3 groups: users of generic warfarin formulations from a single drug manufacturer (generic-only group), users of branded warfarin formulations only (brand-only group), and patients who used generic and branded warfarin therapy interchangeably or who may have used generic drugs from 1 or more manufacturers (generic/brand switching group). Patients were followed 12 months or longer after their index warfarin prescription date to compare all-cause resource use and costs using multivariable regression analysis.

Results:

The analysis included 12,908 patients: 71.82% were in the generic-only group, 9.61% were in the brand-only group, and 18.57% were in the generic/brand switching group. Patients in the generic/brand switching group were more likely to be hospitalized (relative risk [RR] = 1.43, p < 0.0001) or to use emergency department services (RR = 1.20, p < 0.01), compared to the brand-only users. Hospitalizations were more likely (RR = 1.26, p < 0.001) to occur among generic-only users versus brand-only users. Adjusted mean pharmacy costs per member per month were lower in the generic/brand switching group compared to the brand-only group ($257 vs $273, p = 0.038), but inpatient costs were higher ($1250 vs $972, p < 0.001), resulting in higher ($2125 vs $1847, p < 0.001) total costs. Generic-only users had lower pharmacy costs compared to brand-only users ($246 vs $273, p < 0.001), but total health care costs trended to be higher in the generic-only group ($1957 vs $1847, p = 0.053).

Conclusions:

The use of both generic and branded formulations of warfarin interchangeably, or the use of generics from more than 1 manufacturer, was associated with increased use of all-cause health care resources and total costs in patients with AF.

2012 HRS/EHRA/ECAS expert consensus statement on catheter and surgical ablation of atrial fibrillation: recommendations for patient selection, procedural techniques, patient management and follow-up, definitions, endpoints, and research trial design

This is a report of the Heart Rhythm Society (HRS) Task Force on Catheter and Surgical Ablation of Atrial Fibrillation, developed in partnership with the European Heart Rhythm Association (EHRA), a registered branch of the European Society of Cardiology and the European Cardiac Arrhythmia Society (ECAS), and in collaboration with the American College of Cardiology (ACC), American Heart Association (AHA), the Asia Pacific Heart Rhythm Society (APHRS), and the Society of Thoracic Surgeons (STS). This is endorsed by the governing bodies of the ACC Foundation, the AHA, the ECAS, the EHRA, the STS, the APHRS, and the HRS.