Retrospective review of Arctic Front Advance Cryoballoon Ablation: a multicenter examination of second-generation cryoballoon (RADICOOL trial)

Background

Pulmonary vein isolation (PVI) via catheter ablation is an approved therapy for patients with drug-refractory and symptomatic atrial fibrillation (AF). Furthermore, cryoballoon is now considered to be as effective as focal radiofrequency catheter ablation. This study examines the second-generation cryoballoon performance in a US multicenter review of real-world practices.

Methods

By retrospective chart collections, the long-term efficacy and safety of the cryoballoon procedure were assessed in 15 US centers. All patients had a history of drug-refractory symptomatic paroxysmal AF and were treated with a cryoballoon PVI strategy at the index ablation.

Results

Four hundred fifty-two patients were evaluated, and acute PVI was achieved in 99% of patients by cryoballoon catheter ablation. In 0.88% of patients (4/452), an additional focal ablation catheter was used to achieve acute PVI during the ablation procedure. Average procedure time was 128 (range 82 to 260) min, using an average of 17 (range 1 to 19) min of fluoroscopy. The most frequent adverse event was transient phrenic nerve injury (1.5%; 7/452 patients) which all resolved by the end of the procedure with no diaphragmatic dysfunction at discharge. There were no strokes, transient ischemic attacks, cardiac tamponade, atrioesophageal fistulas, or deaths during the study. At the 12-month efficacy endpoint, single-procedure success of freedom from atrial arrhythmia was 87% (393/452 patients).

Conclusions

This real-world examination of the US practice demonstrates that second-generation cryoballoon ablation by PVI strategy is safe and effective among patients with paroxysmal AF.

     

Single 3-min freeze per vein ablation strategy with the second-generation cryoballoon for atrial fibrillation in a large cohort of patients: long term outcome after a single procedure

Purpose

The purpose of the present study was to assess the long-term success rate of a single 3-min freeze per vein ablation strategy in the setting of pulmonary vein isolation (PVI) by means of second-generation cryoballoon (CB-A; Arctic Front Advance, Medtronic, Minneapolis, MN, USA) in a large cohort of patients.

Methods

Three hundred and one patients with drug resistant atrial fibrillation (AF) having undergone PVI by means of CB-A using a single 3-min freeze per vein ablation strategy were included in the analysis.

Results

Paroxysmal AF (PAF) was documented in 70.8% of the patients, while 29.2% presented with persistent AF (PersAF). The mean number of CB applications was 1.09?±?0.3 in the left superior pulmonary vein (LSPV), 1.04?±?0.2 in the left inferior pulmonary vein (LIPV), 1.12?±?0.3 in the right superior pulmonary vein (RSPV), and 1.12?±?0.3 in the right inferior pulmonary vein (RIPV). All PVs were successfully isolated with a 28-mm CB-A only. After a mean follow-up of 38.1?±?7.5 months, 207 (68.8%) patients were free of atrial tachyarrhythmia (ATa) recurrences following a single procedure. Specifically, 72.8% of patients presenting with PAF and 59.1% of individuals with PersAF did not experience a recurrence.

Conclusions

A single 3-min freeze per vein strategy is effective in treating AF on a long term follow-up of 38 months. Specifically, it can afford freedom from ATa recurrences in 72.8% of patients affected by PAF and 59.1% of patients initially presenting with PersAF after a single CB-A procedure.

     

Very long-term outcomes after a single catheter ablation procedure for the treatment of atrial fibrillation—the protective role of antiarrhythmic drug therapy

Background

Pulmonary vein isolation (PVI) is the cornerstone of AF ablation, but its long-term clinical outcomes, predictors of relapse, and optimal pharmacological treatment remain controversial.

Objective

The objectives of this paper were to (1) assess very long-term AF recurrence, (2) identify predictors of relapse, and (3) evaluate the impact of continued antiarrhythmic drug (AAD) treatment after ablation.

Methods

Multicenter observational registry including all consecutive patients with drug-resistant AF who underwent a first PVI between 2006 and 2008 (n?=?253 (age 55 years (IQR 48–63)), 80% males, 64% with paroxysmal AF. Endpoint was AF/AT/AFL relapse after a 3-month blanking period. Predictors and protective factors of AF relapse were assessed with multivariate Cox regression.

Results

A total of 144 patients (57%) relapsed over a median 5-year (IQR 2–9) follow-up—annual relapse rate of 10%/year. Female sex (aHR 1.526, 95% CI 1.037–2.246, P?=?0.032), non-paroxysmal AF (aHR 1.410, 95% CI 1.000–1.987, P?=?0.050), and LA volume/BSA (aHR 1.012, 95% CI 1.003–1.021, P?=?0.008) were identified as independent predictors of relapse. A total of 139 patients (55%) continued AAD (55% on amiodarone) after blanking period. One-year overall PVI success rate of patients under AAD was 86 vs 76% with no AAD (P?<?0.001)—annual relapse rates were 8%/year vs 14%/year (P?<?0.001), respectively. AAD was associated with a long-term reduction in AF relapse (aHR 0.673, 95% CI 0.509–0.904 P?=?0.004).

Conclusion

Half the patients remained free from AF 5 years after a single procedure. Female sex, non-paroxysmal AF, and LA volume/BSA independently predicted recurrence, whereas continuing AAD after the 3-month blanking period reduced relapse.

Condensed abstract

In a multicenter registry of AF patients undergoing a first PVI, 57% relapsed over a median 5-year follow-up. Female sex, non-paroxysmal AF and LA volume/BSA were identified as independent predictors of relapse. Maintaining AAD therapy after the blanking period was associated with a long-term reduction in AF relapse.

     

Long-term follow-up in patients treated by stent implantation for post-ablation pulmonary vein stenosis

Purpose

Symptomatic severe pulmonary vein stenosis (PVS) after catheter ablation of atrial fibrillation (AF) is a rare but well-recognized complication. Treatment options include pulmonary vein angioplasty with or without drug eluting balloons or angioplasty with stent implantation. The treatment of choice is unclear. In our center, pulmonary vein stenting is the treatment of choice for significantly stenotic veins. We present the long-term clinical outcome of 9 patients treated with stent implantation.

Methods

Between 2001 and 2015, 3048 patients with AF were treated with catheter ablation at our institution, of which 9 developed symptomatic PVS. A total of 11 PVS were treated. Pre-procedural imaging (CT, MR, transesophageal echocardiography, angiography) was performed in all patients.

Results

Mean time from ablation to stenting was 18 months. Three patients had recurrent pneumonia and the remaining reduced functional capacity (NYHA 2). All patients were in functional capacity NYHA 1 (p?<?0.05) after a mean follow-up of 64 (18–132) months. Three patients still had paroxysmal AF, of which two have undergone repeated ablation.

Conclusions

Symptomatic PVS after AF ablation can be successfully treated by stent implantation with durable results and good clinical outcome. AF ablation is still a feasible option after stent deployment.

     

Pulmonary vein isolation combined with spironolactone or renal sympathetic denervation in patients with chronic kidney disease,uncontrolled hypertension,paroxysmal atrial fibrillation,and a pacemaker

Background

Atrial fibrillation (AF) commonly occurs in chronic kidney disease (CKD), occasioning adverse outcomes. Merging pulmonary vein isolation (PVI) and renal sympathetic denervation (RSD) may decrease the recurrence of AF in subjects with CKD and uncontrolled hypertension. We considered that RSD could reduce the recurrence of AF in patients with CKD by modulating sympathetic hyperactivity. We aimed to evaluate the impact of RSD or spironolactone 50 mg/day associated with PVI in reducing systolic blood pressure (BP), AF recurrence, and AF burden in patients with a history of paroxysmal AF and mild CKD.

Methods

This was a single-center, prospective, longitudinal, randomized, double-blind study. The individuals were randomly divided into two groups (PVI?+?spironolactone, n?=?36, and PVI?+?RSD, n?=?33). All of them were followed for exactly 1 year to assess maintenance of sinus rhythm and to monitor the other variables.

Results

Ambulatory BP measurements were reduced in both groups and at the 12th month also differed between groups. Significantly more patients in the PVI?+?RSD (61%) than in the PVI?+?spironolactone group (36%) were AF-free at the 12th month of follow-up, P?=?0.0242. Toward the end of the study, the mean AF burden was lower in the PVI?+?RSD group as compared to PVI?+?spironolactone group, at the 9th month: ??=???10% (P?<?0.0001), and at the 12th month: ??=???12% (P?<?0.0001), respectively.

Conclusions

PVI?+?RSD is safe and appears to be superior to PVI?+?spironolactone in BP reduction, augmentation of AF event-free rate, reduction of AF burden, and improvement of renal function.

     

Long-Term Outlook after Successful Fibrin Glue Ablation of Cryptoglandular Transsphincteric Fistula-in-Ano

Purpose

Initial success rates for fibrin glue ablation of cryptoglandular transsphincteric fistulas have been disappointing. We examined long-term outcomes after initially successful fibrin glue ablation of cryptoglandular transsphincteric fistulas.

Methods

Retrospective review identified 36 adult patients with cryptoglandular transsphincteric fistula Tisseel VH® fibrin glue ablation that was performed from May 2000 to March 2005. Fibrin glue ablations were performed under supervision of fellowship-trained colorectal surgeons. Follow-up interval was based on time until recurrence of fistula or time of last fistula-free evaluation.

Results

Twenty-four men and 12 women patients had a mean age of 50 (range, 27–85) years. Twenty patients responded to initial fibrin glue ablation treatment. Two additional patients healed with secondary fibrin glue ablation. Sixty-six percent (22/33 patients) of cryptoglandular transsphincteric fistulas were closed at three months. Eleven patients failed fibrin glue ablation at a mean of 33 (range, 6–41) days. Seventeen of 22 short-term success patients (3 months) were available for long-term follow-up. Ninety-four percent (16/17 patients) remained healed at final long-term follow-up. The remaining patient recurred just before the six-month follow-up.

Conclusions

Despite the suboptimal early success rate of fibrin glue ablation for cryptoglandular transsphincteric fistulas, when a fistula does close for at least six months this appears to be a durable closure. A single patient recurred after appearing healed at the three-month check.

     

Electrical isolation of the superior vena cava by laser balloon ablation in patients with atrial fibrillation

Purpose

The aim of the present study is to evaluate the feasibility and safety of SVC electrical isolation by LB ablation in patients with atrial fibrillation (AF) referred for pulmonary vein isolation (PVI).

Methods

Electrical disconnection of the SVC was attempted by LB in 13 consecutive patients (59?±?10.5 years, 11 male) with AF following PVI. PVI was successfully achieved by standard LB in all before attempting SVC isolation.

Results

A laser beam was delivered with 6.3?±?2.3 W and 8.4?±?2.7 W (P?=?0.001) during 5.38?±?2.4 min and 9.75?±?1.6 min (P?=?0.024) to achieve SVC and PV, respectively. Isolation of the SVC by LB was accomplished in 8 patients (61%) without complications. Phrenic nerve palsy developed in 3 patients (23%), which resulted in early procedure termination before isolation. Technical problems or interposition of a pacemaker lead to prevented SVC isolation in the remaining 2 patients. After a mean follow-up of 19?±?3 months, no patient recovered from phrenic nerve palsy.

Conclusions

SVC isolation by LB is feasible but associated with a high risk of phrenic nerve palsy. Limitation of laser delivery time and power appears insufficient to prevent this complication.

     

Atrial resynchronization therapy in patients with atrial fibrillation and heart failure with and without systolic left ventricular dysfunction: a pilot study

Purpose

The superiority of catheter ablation (CA) for persistent (and long-standing persistent) atrial fibrillation (AF) is currently not well defined. We performed a meta-analysis of randomized controlled trials (RCTs) to assess the clinical outcomes of CA compared with medical therapy in persistent AF patients.

Methods

We systematically searched PubMed, EMBASE, the Cochrane Library, and clinicaltrials.gov for RCTs comparing CA with medical therapy in patients with persistent AF. For CA vs medical rhythm control, the primary outcome was freedom from atrial arrhythmia. For CA vs medical rate control, the primary outcome was the change in the left ventricular ejection fraction (LVEF).

Results

Eight studies with a total of 809 patients were included in the final analysis. Compared with medical rhythm control, CA was superior in achieving freedom from atrial arrhythmia (RR 2.08, 95% CI [1.67, 2.58]; P?<?0.00001). Similar result was found in CA arm without antiarrhythmic drug use after operation (RR 1.82, 95%CI [1.33, 2.49]; P?=?0.0002). CA was also superior in reducing the probability of cardioversion (RR 0.59, 95%CI [0.46, 0.76]; P?<?0.0001) and hospitalization (RR 0.54, 95%CI [0.39, 0.74]; P?=?0.0002). Compared with the medical rate control in persistent AF patients with heart failure (HF), CA significantly improved the LVEF (MD 7.72, 95%CI [4.78, 10.67]; P?<?0.00001) and reduced Minnesota Living with Heart Failure Questionnaire scores (MD 11.1395% CI [2.52–19.75]; P?=?0.01).

Conclusions

CA appeared to be superior to medical therapy in persistent AF patients and might be considered as a first-line therapy for some persistent AF patients especially for those with HF.

     

Renal function after repeat catheter ablation for long-standing persistent atrial fibrillation

Background

Renal impairment and atrial fibrillation (AF) often coexist. Catheter ablation is an effective way to reduce the burden of AF and improve symptoms; however, little is known about the relationship between renal function and AF and its role in the progression of AF for patients undergoing repeat catheter ablation.

Methods

In all, 171 patients with long-standing persistent AF ablation were enrolled in the study. The patients were divided into two groups according to their delta estimated glomerular filtration rate (eGFR) values, which was defined as the eGFR before the repeat procedure minus the eGFR before the initial procedure. Patients with decreasing eGFR (delta eGFR <?0) were categorized as group I, while individuals with no change or increasing eGFR (delta eGFR≥?0) were categorized as group II. eGFR was estimated at baseline and at the 12-month and 24-month follow-up visits.

Results

After a mean follow-up of 31.4?±?13.2 months, group I had a significantly higher arrhythmia recurrence rate than group II (71.2 vs. 49.2?%, p?<?0.001). On multivariable analyses, eGFR changes after the repeat procedure were associated with arrhythmia recurrence, hypertrophic cardiomyopathy, and CHA₂DS₂-VASc score. Patients with arrhythmia recurrence and those with a CHA₂DS₂-VASc score of ≥?3 were more likely to show an eGFR decline at follow-up.

Conclusion

Patients with long-standing persistent AF, with a failed initial ablation procedure and undergoing a repeat ablation procedure, appear to have a higher risk of arrhythmia recurrence. During the follow-up period, patients without arrhythmia recurrence and those with a CHA₂DS₂-VASc score of <?3 show improved renal function.

     

Impact of 3D mapping on procedural characteristics and outcomes in cryoballoon pulmonary vein isolation for atrial fibrillation

Purpose

The use of 3D mapping during cryoballoon pulmonary vein isolation (PVI) is optional with added cost but potential benefit in aiding vein identification, reducing fluoroscopy, and post-ablation testing. Data are limited evaluating procedural characteristics and outcomes in patients undergoing cryoballoon PVI with mapping vs. no mapping. In the present study, we compare procedural characteristics and recurrence-free rates in patients undergoing cryoballoon PVI among patients using CARTO®, NavX?, or no mapping system.

Methods

We evaluated a single center registry of patients undergoing cryoballoon PVI from 2013 to 2016, retrospectively. Patients undergoing a redo procedure or additional RF ablation were excluded. Baseline and procedural characteristics were compared among CARTO, NavX, and no mapping groups. Post-PVI patients were assessed for atrial arrhythmia recurrence after a 3-month blanking period. Recurrence was based on typical symptoms or ECG/event monitor evidence of atrial fibrillation (AF). Kaplan-Meier analysis was used to compare arrhythmia-free survival between groups.

Results

We included 432 patient procedures, 98 using mapping systems (45 NavX, 53 CARTO), and 334 without. When using the CARTO mapping system compared to NavX or no mapping, there were longer procedure times (168 vs.109 vs.115 min, p?<?0.001) and LA dwell times (110 vs.81 vs.87 min, p?<?0.001). Additionally, both CARTO and NavX, when compared to no mapping, had longer fluoroscopy times (32 vs.31 vs.26 min, p?<?0.001). Overall, total ablation time was increased for patients without mapping systems compared to NavX. There were no significant differences in 1-year recurrence-free rates between CARTO, NavX, and no mapping groups (64.9 vs. 65.0 vs. 64.6%, p?=?0.278).

Conclusion

Use of CARTO is associated with increased procedure and LA dwell times compared to NavX or no mapping. Mapping system use yielded longer fluoroscopy times without an improvement in atrial fibrillation recurrence. Given the additional cost of mapping, the role for routine use in cryoballoon PVI is unclear.

     

Rabbit model to simulate the residual conduction gaps after radiofrequency ablation on the anterior wall of left atrial appendage

Purpose

The optimal radiofrequency (RF) power and lesion duration using contact force (CF) sensing catheters for atrial fibrillation (AF) ablation are unknown. We evaluate 50 W RF power for very short durations using CF sensing catheters during AF ablation.

Methods

We evaluated 51 patients with paroxysmal (n?=?20) or persistent (n?=?31) AF undergoing initial RF ablation.

Results

A total of 3961 50 W RF lesions were given (average 77.6?±?19.1/patient) for an average duration of only 11.2?±?3.7 s. As CF increased from ?40 g, the RF application duration decreased from 13.7?±?4.4 to 8.6?±?2.5 s (p??40 g of force. As CF increased, the force time integral (FTI) increased from 47?±?24 to 376?±?102 gs (p?p?

Conclusions

Short duration 50 W ablations using CF sensing catheters are safe and result in excellent long-term freedom from AF for both paroxysmal and persistent AF with short procedure times and small amounts of total RF energy delivery.

     

Efficacy and safety of catheter ablation vs. rate control of atrial fibrillation in systolic left ventricular dysfunction

Purpose

It is unclear what constitutes the optimal strategy for management of atrial fibrillation (AF) in patients with systolic left ventricular (LV) dysfunction. We hypothesized that catheter ablation of AF had benefits compared with rate control in patients with systolic LV dysfunction.

Methods

PubMed, Embase, and the Cochrane Library were searched for randomized controlled trials and nonrandomized, observational studies. Weighted mean differences (WMD) and 95?% confidence intervals (CIs) were calculated to compare the improvement of left ventricular ejection fraction (LVEF), functional capacity, and quality of life between a catheter ablation group and a rate control group.

Results

Six trials with 324 patients were included in the analysis. Patients in the catheter ablation group had greater improvement of LVEF (WMD: 8.89; 95?% CI: 6.93–10.86; p?<?0.001), 6-min walk distance (WMD: 46.9; 95?% CI: 28.5–65.4; p?<?0.001), and lower Minnesota Living With Heart Failure Questionnaire (MLHFQ) scores (WMD: ??19.6; 95?% CI: ??23.6–??15.7; p?<?0.001) compared with patients in the rate control group. Overall, there were only ten procedure-related events and the procedure-related events rate was 4.9?% per procedure and 5.6?% per patient.

Conclusion

The present analysis suggests that catheter ablation of AF has benefits in terms of an improvement in LVEF, in functional capacity, and in quality of life compared with rate control in patients with systolic LV dysfunction, and the risk of complications related to procedures is acceptable.

     

Current State of Left Atrial Appendage Closure

Purpose of Review

Atrial fibrillation (AF), the most common sustained arrhythmia, is a major cause of stroke and systemic embolism, and is increasing in prevalence. Device closure of the left atrial appendage (LAA) represents a non-pharmacologic approach to stroke prevention in AF patients. This review presents the rationale for LAA closure (LAAC), describes current transcatheter approaches to LAAC, and summarizes the current evidence for LAAC for stroke prevention, highlighting the main randomized trials and the most recent data available.

Recent Findings

Meta-analysis of randomized clinical trials demonstrates similar rates of all-cause stroke with transcatheter LAAC compared with vitamin K antagonist therapy and significantly less bleeding with LAAC after cessation of mandated post-procedure pharmacology. Recent prospective observational studies, including those evaluating outcomes after commercial approval in the USA, show significantly improved procedure safety compared with earlier experiences.

Summary

LAAC appears to be an attractive alternative strategy for stroke prevention in AF patients, particularly in those who can take short-term oral anticoagulation (OAC), but are not optimal candidates for long-term OAC. Recent data suggests the procedure can be safely performed in patients with contraindications to OAC. Further, robust studies are needed to evaluate safety and efficacy in OAC-contraindicated patients, to compare outcomes with non-vitamin K antagonist OACs, and to explore the relative safety and efficacy of different LAAC devices.

     

Acute pericarditis following second-generation cryoballoon ablation for atrial fibrillation

Purpose

Acute pericarditis is a minor complication following atrial fibrillation (AF) ablation procedures. The aim of the study was to evaluate the incidence and clinical aspects of pericarditis following cryoballoon (CB) ablation of AF investigating a possible association with procedural characteristics and a possible relationship with post-ablation recurrences.

Methods

Four hundred fifty consecutive patients (male 73%, age 59.9?±?11.2 years) with drug-resistant paroxysmal AF who underwent CB ablation as index procedure were enrolled. Exclusion criteria were any contraindication for the procedure including the presence of intracavitary thrombus and uncontrolled heart failure and contraindications to general anesthesia.

Results

Acute pericarditis following CB ablation occurred in 18 patients (4%) of our study population. Pericardial effusion occurred in 14 patients (78%) and was mild/moderate. The total number of cryoapplications and the total freeze duration were significantly higher in patients with pericarditis compared with those without (respectively, p?=?0.0006 and p?=?0.01). Specifically, the number of applications and freeze duration in right inferior pulmonary vein were found significantly higher in patients with pericarditis (p?=?0.007). The recurrence rate did not significantly differ between the two study groups (respectively, 16.7 vs 18.1%; p?=?0.9).

Conclusions

The incidence of acute pericarditis following CB ablation in our study population accounted for 4% and was associated with both total freezing time and number of cryoapplications. The clinical course was favorable in all these patients and the occurrence of acute pericarditis did not affect the outcome during the follow-up period.

     

Assessment of autonomic nervous system modulation after novel catheter ablation techniques for atrial fibrillation using multiple short-term electrocardiogram recordings

Purpose

The effect of novel catheter ablation techniques for atrial fibrillation (AF) on the autonomic nervous system (ANS) is unclear. This study aimed to assess the ANS after three novel catheter ablation techniques for paroxysmal AF by evaluating heart rate variability (HRV) parameters using a 3-min electrocardiogram recording.

Methods

Two hundred and thirty-five patients who underwent catheter ablation for paroxysmal AF (119 in irrigated-tip, 51 in contact-force sensing-guided, and 65 patients in second-generation cryoballoon ablation) were included. HRV analysis was performed at baseline and 1, 3, 6, and 12 months after the ablation.

Results

The three ablation groups had similarly decreased HRV parameters after the ablation, and this change was maintained > 1 year. A reduction in parasympathetic nervous function was more apparent after the ablation, compared to changes in the sympathetic nervous function. Of the total population, 45 patients had recurrence. Ln high frequency (HF) 12 months after the ablation was significantly higher in the recurrence group than in the non-recurrence group (1.52 ± 0.47 vs. 1.26 ± 0.57 ms², p = 0.007). Multivariate analysis demonstrated that AF duration (hazards ratio 1.09, 95% confidence interval 1.04–1.15, p = 0.001) and ln HF 12 months after ablation (hazards ratio 1.91, 95% confidence interval 1.12–3.25, p = 0.017) were independent predictors of AF recurrence after the ablation.

Conclusions

ANS modulation after the three catheter ablation methods was similar and maintained > 1 year after the procedure. Higher parasympathetic nervous function at 1 year after ablation was associated with AF recurrence after the ablation.

     

Value of an old school approach: safety and long-term success of radiofrequency current catheter ablation of atrioventricular nodal reentrant tachycardia in children and young adolescents

Purpose

Radiofrequency current energy (RFC) ablation is still considered as the gold standard for atrioventricular nodal reentrant tachycardia (AVNRT). Success-rates for AVNRT ablation vary irrespective of the ablation technology and strategy. This study aimed to access safety, efficacy, and long-term outcome of RFC catheter ablation for the treatment of AVNRT in children and adolescents aged <?19 years with special focus on modulation versus ablation of the AV nodal slow pathway (SP).

Methods

A total number of 1143 patients (pts) <?19 years were referred for invasive electrophysiological testing due to paroxysmal supraventricular tachycardia (SVT).

Results

Diagnosis of AVNRT was confirmed in 412 pts, and RFC-guided ablation was attempted in 386 pts (age 13.0?±?3.5 years). No permanent complications were observed. RFC application resulted in SP-ablation in 171/386 (44.3%) and in SP modulation in 208/386 (53.9%) children, whereas attempts for RFC treatment failed in 7 pts. Follow-up was completed for 396/412 patients (96.1%). Within a mean follow-up period of 54.9?±?39.7 months, in 51/379 pts (13.5%) AVNRT recurrence was observed. The median time until tachycardia recurrence was 19.5 months. No difference for AVNRT recurrence was found comparing SP ablation versus SP modulation (p >?0.05), whereas the recurrence rate was significantly higher in patients with non-inducible SVT and therefore empiric SP treatment as compared to patients with inducible AVNRT (p =?0.01).

Conclusions

RFC-guided ablation for AVNRT in children and adolescents is safe and leads to an acceptable long-term freedom from recurrences. SP modulation and SP ablation resulted in comparable acute and long-term success rates. Late AVNRT recurrences can occur even after years of freedom from tachycardia-related symptoms.

     

Implantierbare Loop-Rekorder bei Vorhofflimmern und nach Katheterablation

Background

Implantable loop recorders (ILR) are an established diagnostic method for detection of cardiac arrhythmias including atrial fibrillation.

Objective

The aim of this work is to provide an overview of available data and indications of ILR in atrial fibrillation, especially after catheter ablation, in order to illustrate practice-oriented recommendations.

Materials and methods

We conducted a selective PubMed literature search.

Results and Discussion

ILR can record asymptomatic/rare atrial fibrillation episodes and prevent thromboembolic events by allowing timely initiation of oral anticoagulation. They can be used to assess therapeutic success after percutaneous or surgical ablation, if despite increased thromboembolic risk, no oral anticoagulation is desired. ILR equipped with remote monitoring function and special P wave detection algorithms may improve diagnostic confidence.

     

Left Atrial Appendage Closure for Stroke Prevention in Atrial Fibrillation

Purpose of Review

Anticoagulant therapy effectively reduces the incidence of stroke in patients with atrial fibrillation (AF) but is underutilized and frequently contraindicated. The left atrial appendage (LAA) is the primary site of thrombus formation in AF patients. Surgical and percutaneous appendage closure has been evaluated as a site-specific therapy to reduce systemic thromboembolism.

Recent Findings

We will review LAA closure techniques, examine recent outcome data, and discuss the indications for, and potential complications of, each approach.

Summary

Randomized data examining surgical LAA closure and epicardial closure with the LARIAT device are lacking. High quality, randomized data supports the efficacy of the WATCHMAN device for stroke prevention in patients with AF.

     

A contemporary view of atrioventricular nodal physiology

Purpose

Catheter ablation is an effective treatment for premature ventricular complexes (PVCs). Activation mapping is accurate but requires PVCs at the time of the ablation. Pace-mapping correlation (PMC) is a supplemental tool recently developed as an integrated module for an electro-anatomical mapping platform. Our study sought to investigate whether pace-mapping technology provides similar ablation results in patients with low versus high idiopathic PVC burden at the time of ablation and the relationship between sites with the highest PMC and the earliest local activation time (LAT).

Methods

A total of 59 consecutive patients undergoing catheter ablation for idiopathic PVCs were enrolled. Twelve out of 59 patients (20%) were classified in the low PVC burden group (defined as <?2 PVCs/min) and 47/59 (80%) in the high PVC burden group.

Results

The most common origin of PVCs was the right ventricular outflow tract (RVOT) followed by aortic cusps, coronary sinus, parahisian region, and aorto-mitral continuity. Procedural and 1-month success rate were 95 and 87% respectively. PVC burden at the time of ablation did not influence the success rate. The median distance between the earliest LAT points and the highest PMC points was 6.4 (4.9–10.6) mm.

Conclusions

Pace-mapping correlation is useful and accurate in localizing the origin of idiopathic PVCs irrespective of the initial PVC burden. It provides optimal ablation results when combined with LAT. Success rate at mid-term follow-up is higher when the origin of PVCs is located in the RVOT as compared to other locations.

     

Atrial Fibrillation (AF) in Endurance Athletes: a Complicated Affair

Purpose of review

A complex relationship exists between exercise and atrial fibrillation (AF). Moderate exercise reduces AF risk whereas intense strenuous exercise has been shown to increase AF burden. It remains unclear at which point exercise may become detrimental. Overall, endurance athletes remain at lower cardiovascular risk and experience fewer strokes. The questions that arise therefore are whether AF is an acceptable byproduct of strenuous exercise, whether athletes who experience AF should be told to reduce exercise volume and how should they be managed. This review aims to critically review the literature and advise on how best to manage athletes with AF.

Recent findings

Emerging evidence suggests that female athletes may exhibit lower risk of AF, but data is limited in female endurance athletes.

Summary

AF is more prevalent in endurance athletes, particularly men and those who competed at a young age. Data is lacking in females and ethnic minorities. Current evidence suggests that treatment options for AF in athletes are similar to those used in the general population; however, medical therapy may be poorly tolerated. Catheter ablation is effective and can allow return to full competition.