Pulmonary Vein Isolation Procedure Research Articles

Prolongation of QT interval after pulmonary vein isolation for paroxysmal atrial fibrillation.

Pulmonary vein isolation (PVI) affects the ganglionated plexi (GP) around the atrium leading to a modification of intrinsic cardiac autonomic system (ANS). In animal models, GP ablation has the potential risk of QT prolongation and ventricular arrhythmias. However, the impact of PVI on QT intervals in human remains unclear. We analyzed electrocardiograms of 117 consecutive patients with paroxysmal atrial fibrillation (AF) who underwent their first PVI procedures and maintained sinus rhythm without antiarrhythmic drugs at all evaluation points (4 h, 1 day, 1 month, and 3 months after PVI). Heart rate significantly increased at 4 h, 1 day, and 1 month. Raw QT interval prolonged at 4 h (417.1 ± 41.6 ms, p < .001) but shortened at 1 day (376.4 ± 34.1 ms, p < .001), 1 month (382.2 ± 31.5 ms, p < 0.001), and 3 months (385.1 ± 32.8 ms, p < 0.001) compared with baseline (391.6 ± 31.4 ms). Bazett-corrected QTc intervals were significantly prolonged at 4 h (430.8 ± 27.9 ms, p < .001), 1 day (434.8 ± 22.3 ms, p < .001), 1 month (434.8 ± 22.3 ms, p < .001), and 3 months (420.1 ± 21.8 ms, p < .001) compared with baseline (404.9 ± 25.2 ms). Framingham-corrected QTc intervals significantly prolonged at 4 h (424.1 ± 26.6 ms, p < .001) and 1 day (412.3 ± 29.3 ms, p < .01) compared with baseline (399.2 ± 22.7 ms). Multiple regression analysis revealed that female sex is a significant predictor of raw QT and QTc interval increase at 4 h after PVI. Raw QT and QTc were prolonged after PVI, especially in the acute phase. Female sex is a risk factor for QT increase.

Comparison between minimal fluoroscopy and conventional approaches for visually guided laser balloon pulmonary vein isolation ablation.

Although balloon-based techniques, such as the laser balloon (LB) ablation have simplified pulmonary vein isolation (PVI), procedural fluoroscopy usage remains higher in comparison to radiofrequency PVI approaches due to limited 3-dimensional mapping system integration. In this prospective study, 50 consecutive patients were randomly assigned in alternating fashion to a low fluoroscopy group (LFG;n = 25) or conventional fluoroscopy group (CFG;n = 25) and underwent de novo PVI procedures using visually guided LB technique. There was no statistical difference in baseline characteristics or cross-overs between treatment groups. Acute PVI was accomplished in all patients. Mean follow up was 318 ± 69 days. Clinical recurrence of atrial fibrillation after PVI was similar between groups (CFG: 19% vs LFG: 15%; P = .72). Total fluoroscopy time was significantly lower in the LFG than the CFG (1.7 ± 1.4 vs16.9 ± 5.9 minutes; P < .001) despite similar total procedure duration (143 ± 22vs148 ± 22 minutes; P = .42) and mean LA dwell time (63 ± 15vs59 ± 10 minutes; P = .28). Mean dose area product was significantly lower in the LFG (181 ± 125vs1980 ± 750 μGym2 ; P < .001). Fluoroscopy usage after transseptal access was substantially lower in the LFG (0.63 ± 0.43vs11.70 ± 4.32 minutes; P < .001). Complications rates were similar between both groups (4% vs2%; P = .57). This study demonstrates that LB PVI can be safely achieved using a novel low fluoroscopy protocol while also substantially reducing fluoroscopy usage and radiation exposure in comparison to conventional approaches for LB ablation.

P333Left atrial function by echocardiography is independent of degree of left atrial electrical scar

Abstract Introduction Assessment of left atrial function via transthoracic echocardiography (TTE) is performed most commonly by measuring the transmitral A wave in sinus rhythm. Left atrial (LA) fibrosis plays an important role in the pathogenesis and perpetuation of Atrial Fibrillation (AF). It may be identified by bipolar voltage (BiV) mapping, which can easily be performed at the beginning of a Pulmonary Vein Isolation (PVI) procedure. The relationship between the degree of LA fibrosis, characterised with mapping, and LA function, determined by echocardiography, has not previously been elucidated. Methods Patients were enrolled in a project to evaluate the degree of fibrosis during PVI procedures. Pre-procedure TTEs of those presenting in sinus rhythm were assessed and the transmitral A wave was measured and compared to the degree of scarring seen. The high density electroanatomic maps (HD-EAMs) created during the PVIs were analysed using a novel VHA algorithm after the procedure. All points with voltages &amp;lt; 0.5mV were defined to have electrical scar. Patients were classified into 4 quartiles based on the levels of scar seen (Figure 1). Results 39 patients were included in the evaluation. Average age was 60.6 +/- 13.2 years. 32 (82.0%) of the patients were male. Mean CHADS2VASc score was 1.5. The mean percentage of scar was calculated as 19.6 +/- 15.9%. The average A wave was 0.62 +/- 0.18 ms-1. Pearson’s correlation coefficient showed no relationship between LA scar and either A wave velocities (r = 0.26, p = 0.11) or E:A ratio (r=-0.02, p = 0.91). A significant correlation between A wave velocity and CHADS2VASc was observed (r = 0.49, p = 0.001). Conclusion Our study demonstrates no relationship between degree of LA scarring and reduced LA function on TTE as assessed by the A wave. It has been established that structural remodelling in AF (such as atrial dilatation) may occur independently of the electrical remodelling. A potential explanation for our findings is that the electrical scarring in AF, which results in alterations in refractory periods, precedes the negative remodelling which ultimately results in reduced atrial function. This hypothesis would need to be further evaluated in larger studies. Abstract Figure 1

P1020Persistent AF patients with limited areas of low voltage have a similar benefit from pulmonary vein isolation as compared to paroxysmal AF patients: insight from the SMOP study

Abstract Background Pulmonary vein isolation (PVI) performed with radio-frequency catheter ablation (CA) is an effective therapy for atrial fibrillation (AF). However previous data have suggested that PVI is less effective in persistent (PER) vs. paroxysmal (PAR) AF. Atrial fibrosis and scar, indeed, are an important substrate involved in persistent AF, and some author correlate them to an increased rate of recurrences after CA. For this reason several adjunctive ablation strategies have been suggested for invasive treatment in PER AF pts. However, there is a lack of evidence on their effectivness in current literature. Objective the aim of our study was to assess the rate of AF recurrences in PAR and PER AF patients after a first pulmonary vein isolation (IVP) procedure, and their relationship with low voltage areas of the left atrium assessed by means of high density mapping performed before CA. Methods we analyzed 214 patients of the SMOP-AF study (Substrate Mapping as Outcome Predictor in Atrial Fibrillation Ablation), a prospective multi-centric registry enrolling patients with both PAR and PER AF undergoing a first radio-frequency CA procedure aimed to obtain permanent PVI . High-density mapping was performed in sinus rhythm using the CARTO system before PVI. Areas with less than 0,5 mV on mapping were defined as low voltage zone (LVZ); LVZ was indexed on the atrial area. Comparisons were made by cross-tables and Chi-square test or Student T test. Results Patients with PER AF (n = 44, 21%) were older (63 ± 9 vs 58 ± 10 yrs, p = 0.01), but notably with no difference in LVEF and atrial dimensions as compared to pts with PAR AF. In addition no statistical difference was observed in procedural variables, except for a greater LVZ area on atrial mapping (8 ± 18 % vs. 5 ± 15 %, p = 0.04) and a longer p wave duration (115 ± 21 msec vs. 103 ± 18 msec, p = 0.01) in pts with PER AF. The incidence of recurrence in the overall population was 15.3% at 3 months and 13.7% from 3 to 12 months: there was no statistical difference in success-rate between PER and PAR pts (respectively 79,5% vs 86% p value = 0.315 in blanking period and 85,3% vs 86,5% p value = 0.8 at 3-12 months follow-up). No statistical difference was observed for ablation variables (number of lesion, contact force, force time integral) in pts with vs. without recurrences. Conclusion Our study showed that pulmonary vein isolation alone seems to be as effective in paroxismal and persistent AF patients with low degree of left atrial fibrosis. Our data call into question the idea that PVI alone is not effective in PER AF. High density mapping of the LA could help to identify a subset of PER AF patients with a limited extension of low voltage areas (i.e around 10% of the overall LA surface) that could benefit from PVI without adjunctive ablation strategies. Our data needs to be confirmed in a longer follow-up.

P1027Left atrial hypertension invasively measured during pulmonary vein isolation as a predictor of atrial fibrillation recurrence

Abstract Background The clinical role of left atrial hypertension (LAH) in patients with atrial fibrillation (AF) and its role as predictor in those undergoing pulmonary vein (PV) isolation is still unknown. Purpose The aim of the present study was to analyse the prevalence of LAH in patients with nonvalvular AF and preserved left ventricular ejection fraction having undergone PV isolation and its implication for AF catheter ablation. Methods Consecutive patients with drug resistant AF who underwent PV isolation at San Maurizio Regional Hospital of Bolzano (Italy) as index procedure were retrospectively included in this analysis. Left atrial hypertension was defined as the LA mean pressure &amp;gt;15 mm Hg. Results A total of 98 consecutive patients (71 males, 72%; mean age 60.3 ± 8.4 years) with drug resistant, non valvular AF and preserved LV ejection fraction having undergone index PV isolation procedure were included in the analysis. Eleven patients (11%) underwent radiofrequency ablation and 87 (89%) cryoballoon ablation. The mean LA pressure was 10.7 ± 4.5 mmHg; LAH occurred in 24 (24%) patients. At a mean follow up of 14.6 ± 7.1 months (median 14 months), the success rate without antiarrhythmic therapy was 71.4% (70/98; considering the blanking period). On multivariate analysis, LAH remained the only independent predictor of definitive AF recurrence (HR 3.02, 1.36-6.72, p = 0.007). Conclusion Left atrial hypertension was found in 24% of patients undergoing PV isolation and was found to be significantly related to both early and late AF recurrences. Univariate and multivariate Cox regressi Univariate analysis Multivariate analysis Early Recurrence (during BP) HR 95%CI P value HR 95%CI P value Age (years) 1.06 1.02-1.10 0.005 1.05 1.00-1.09 0.03 LA volume (ml/m2) 1.02 1.00-1.05 0.04 1.02 1.00-1.05 0.05 LA hypertension 2.46 1.32-4.57 0.004 1.97 1.03-3.79 0.04 Recurrence after the BP HR 95%CI P value HR 95%CI P value Age (years) 1.05 1.00-1.11 0.04 1.04 0.98-1.09 0.15 LA hypertension 3.51 1.62-7.60 0.001 3.02 1.36-6.72 0.007 BP recurrence 1.83 0.84-3.99 0.13 AF atrial fibrillation. BMI: body mass index. LA: left atrium. CAD: coronary artery disease. BP: blanking period. HR: hazard ratio. CI: confidence intervals.

664Local catheter impedance drop during pulmonary vein isolation predicts conduction block in patients with paroxysmal atrial fibrillation: initial results of the LOCALIZE clinical trial

Abstract Funding Acknowledgements Boston Scientific Background Radiofrequency (RF) catheter ablation for pulmonary vein isolation (PVI) requires resistively heating cardiac tissue to create conduction block. Creation of an RF lesion results in an impedance drop and the magnitude of this drop depends on the temperature and amount of myocardium being heated. Pre-clinical and clinical evaluation of an advanced local impedance (LI) metric found that greater LI drops were indicative of more effective lesion formation. Purpose To evaluate whether LI drop is associated with conduction block after first pass encirclement of the PVs in patients with paroxysmal AF. Methods LOCALIZE is an ongoing, single-arm, multi-center clinical trial (clinicaltrials.gov NCT03232645). LOCALIZE consists of an index PVI procedure (results presented here) and a 3-month follow-up mapping procedure. In the index procedure, electroanatomical maps of the left atrium were created and ipsilateral PVs were divided into 8 anatomical segments (n = 16 per patient). PVI was performed using point-by-point ablation with blinding of operators to LI. Following initial encirclement and a 20-minute wait period, coronary sinus-paced electroanatomical maps were created to identify gaps within anatomical segments. Gaps were annotated on the map and subsequently ablated. Mean LI drop within each segment was calculated offline as an estimate of regional RF energy delivery (Figure - Left). The diagnostic accuracy of LI drop for predicting segment block was assessed using receiver operating characteristic (ROC) analysis in segments with inter-lesion spacing ≤6mm. Results Forty-seven patients with paroxysmal AF underwent PVI at 5 centers (age 62 ± 11 years, male 55.3%). All patients left the index procedure with all PVs isolated. When blinded to LI (n = 3,064 ablations), median baseline LI was 106 (IQR: 97-115) Ω and median LI drop was 18.4 (12.7-24.9) Ω. After first pass encirclement, blocked segments had a significantly larger LI drop (20.2 [14.6-26.0] Ω) than segments with gaps (10.6 [6.9-15.1] Ω, p &amp;lt; 0.01, Figure - Right). The association between LI drop and block was further evaluated along anatomical anterior/posterior wall thickness differences. Anterior block segments were found to have significantly larger LI drops (21.0 [15.9-27.2] Ω) than posterior block segments (16.6 [12.7-23.7] Ω, p &amp;lt; 0.01). ROC analysis of segments with inter-lesion spacing ≤6mm identified optimal LI cut-off values of 16Ω in anterior segments and 11Ω posteriorly, which had positive predictive values for conduction block of 95.6% and 96.7%, respectively. Conclusions The magnitude of LI drop is predictive of acute PVI segment conduction block in patients with paroxysmal AF. The thinner posterior wall required smaller LI drops for block compared to the thicker anterior wall. With inter-lesion spacing of ≤6mm, reaching a LI drop of ≥16Ω anteriorly and ≥11Ω posteriorly was highly predictive of acute segment block in de novo PVI. Abstract Figure. Local impedance drop in de novo PVI

P456Ultrasound guidance for femoral venous access in patients undergoing pulmonary vein isolation: a quasi-randomized study

Abstract Background The most common complications of electrophysiology (EP) procedures are related to vascular access. Purpose Our study aimed to compare the ultrasound (US)-guided (Group 1) vs. palpation-based (Group 2) technique for femoral venous access in atrial fibrillation (AF) ablation procedures. Methods Between January 2018 and October 2019, 355 patients undergoing pulmonary vein isolation (PVI) on uninterrupted anticoagulant treatment were included. They were allocated to Group 1 or 2 based on which of the two procedure rooms their procedure was scheduled in, with only one of the rooms equipped with an US machine including an 8 MHz linear transducer. Major and minor complications and the rate of prolonged hospitalization were compared in the two groups. Major vascular complication was defined as groin hematoma, arteriovenous fistula, or pseudoaneurysm. Hematoma was considered as a major vascular complication if it met type 2 or higher Bleeding Academic Research Consortium (BARC) criteria (requiring nonsurgical, medical intervention by a health care professional; leading to hospitalization or increased level of care, or prompting evacuation). Results Of the 355 patients 105 were allocated to Group 1 and 250 included in Group 2. Compared to the standard technique, the use of US significantly reduced both major (from 5.60% to 0.95%, p = 0.047) and minor (from 6.40% to 0.95%, p = 0.029) vascular complications. The absolute risk reduction (ARR) of minor/major vascular complications was 10.10% equated to a relative risk reduction (RRR) of 84.13%, and a number needed to treat (NNT) of 10 to prevent one bleeding event. No difference was found for the rate of prolonged hospitalization (5.04% vs. 0.95%, p = 0.119). Conclusion With the use of US for the femoral vein puncture in patients undergoing PVI procedure the rate of both major and minor vascular complications were lower.

P435Reproducibility and predictive value of a simple novel method to measure pulmonary vein activity in persistent atrial fibrillation FARS AF CL study

Abstract Funding Acknowledgements No disclosure Introduction. Pulmonary vein (PV) firing can trigger or act as a rapid driver to maintain atrial fibrillation (AF). Automated 1-minute measurement of fragmented and non-fragmented PV activity cycle length (CL) showed contradictory results to predict ablation outcome in persistent AF. Purpose. This study investigated the reproducibility of a novel non-automated simple method to measure non-fragmented fastest discrete consecutive AF signal cycle length and the value of this measurement in the PVs to predict long-term success after pulmonary vein isolation (PVI) only ablation in persistent AF. Methods. Consecutive 75 patients with persistent AF undergoing first-time PVI between 2015 and 2018 were included. The mean of 10 FAstest Repetitive Similar morphology discrete signal cycle lengths (FARS-AF CL) were measured twice with &amp;gt; 2 minutes between in the coronary sinus (CS), superior vena cava (SVC), left and right atrial appendage (LAA, RAA) and PVs. FARS discrete AF signals were defined as (I) signal duration ≤80 msec; (II) repetitive similar morphological characteristics; (III) fastest consecutive 10 intervals during 1-minute observation. The reproducibility of the FARS–AF CL measurement was compared to traditional 10 consecutive interval measurements of fragmented CS signals. The CL gradient between the PV and the LA was quantified by the computing the ratio of the PV and LAA or CS CL. Results. Good correlation was found between two FARS CL measurements in the CS, PVs, LAA and RAA (Correlation Kendall area: 0.882, 0.675-0.941, 0.859, 0.944, respectively). The correlation between two traditional CL measurements of fragmented CS signals was low (Correlation Kendall area:-0.006). After a mean follow-up of 20 months, freedom from atrial arrhythmias was achieved in 50 (66%) patients after the single PVI procedure with or without the use of AADs. Patient without recurrence were more likely to have FARS CL ≤140 msec (8 vs. 42%, p= 0.002), higher FARS PV CL/LAA CL and FARS PV CL/CS CL ratio (96 ± 13% vs. 86 ± 23 %, p= 0.04; 95 ± 13% vs. 82 ± 22%, p= 0.036). Patients with recurrence at follow-up had more dilated left atria (LAVI: 44 ± 12 vs. 38 ± 9 ml/m2, p= 0.02; LA diameter: 49 ± 6 vs. 45 ± 6 mm, p= 0.01), less AF termination during the procedure (16 vs. 37%, p= 0.049) and less first pass isolation (44 vs. 68%, p= 0.04). Multivariable Cox regression analysis showed that LAVI (p = 0.035) and FARS-PV CL (0.011) were significant predictors of arrhythmia free survival. After adjusting for LAVI, FARS-PV CL remained a significant predictor of AF recurrence (p = 0.028). Conclusions. Traditional non-automated AF CL measurement of fragmented CS signals is poorly reproducible. FARS-AF CL measurements in the PVs, RA and LA structures are highly reproducible. FARS-AF CL measurement in the PVs could predict the success of PVI-only procedure in persistent AF independent of left atrial size.

Patient-reported outcomes after cryoballoon ablation are equivalent between moderate sedation and general anesthesia.

Moderate sedation (MS) during cryoballoon ablation (CBA) avoids risks of general anesthesia (GA) and improves electrophysiology (EP) lab throughput. However, one barrier to the use of MS is the potential for patient discomfort. The objective of this study was to compare patient-reported outcome measures following CBA for paroxysmal atrial fibrillation (pAF) under MS and GA. Consecutive patients undergoing a first CBA for pAF under GA or MS were prospectively enrolled. The sedation method was assigned based on patient and provider preference, and perceived airway risk. The primary outcomes were quality of recovery (measured using a validated 40 question survey; QoR-40) and likelihood to recommend (LTR) the procedure and sedation method (measured by Likert scale). Secondary outcomes were acute pulmonary vein (PV) isolation rate, procedure, fluoroscopy and ablation times, and complication rates. Forty-seven GA and 53 MS patients were included. The mean age was 64.9 ± 9.4 years and mean CHA2 DS2 -VASc score was 2.0 ± 1.4. QoR-40 scores were 184.6 ± 16.4 for GA and 187.6 ± 10.2 for MS (P = .28). LTR responses were similar between groups. Mean procedure times were 148.2 ± 56.0 minutes for GA and 129.4 ± 31.4 minutes for MS (P = .038). Fluoroscopy and ablation times were similar between groups. A total of 100% (409/409) of PVs were acutely isolated. One hemopericardium occurred in the MS group requiring pericardiocentesis. MS for CBA offers an alternative to GA that is safe and well-tolerated by patients with comparable success rates and improved EP lab throughput.

Supplemental Radiofrequency Ablation After Acutely Unsuccessful Cryoballoon Pulmonary Vein Isolation is Associated With Increased Risk of Recurrent Atrial Fibrillation.

BackgroundCryoballoon (CB) ablation is widely performed for pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). Anatomic variations in patient pulmonary vein (PV) anatomy are believed to impact short‐ and long‐term procedural success of CB PVI.Methods and ResultsWe hypothesized that failure of initial PV isolation with a standard technique (ie, requiring >2 freeze cycles per PV and/or radiofrequency ablation [RFA] to achieve PV isolation) during index CB PVI procedures would be associated with decreased freedom from AF. We examined a cohort of 177 consecutive patients with drug‐refractory AF who underwent CB PVI with a 28‐mm balloon second‐generation CB device. Mean follow‐up time was 19±9 months. Forty‐three patients had AF recurrence after the 90‐day blanking period after ablation. In 40 patients, acute isolation of one or more PVs could not be achieved by CB ablation with the standard technique (single freeze with or without bonus freeze). To obtain complete acute PVI, 15 patients received extra freeze applications, 20 required supplemental RFA, and 5 received both extra freeze applications and supplemental RFA. Multivariate regression analysis revealed supplemental RFA use during index CB PVI procedures was independently associated with a threefold increased risk of AF recurrence (adjusted hazard ratio, 3.01; 1.45–10.87; P=0.003).ConclusionsUse of supplemental RFA during CB PVI procedures to assist with isolation of one or more PVs was independently associated with increased risk of AF recurrence. Use of additional freezes to achieve PVI did not increase the risk for recurrent AF.

Atrial fibrillation source area probability mapping using electrogram patterns of multipole catheters

BackgroundCatheter ablation therapy involving isolation of pulmonary veins (PVs) from the left atrium is performed to terminate atrial fibrillation (AF). Unfortunately, standalone PV isolation procedure has shown to be a suboptimal success with AF continuation or recurrence. One reason, especially in patients with persistent or high-burden paroxysmal AF, is known to be due to the formation of repeating-pattern AF sources with a meandering core inside the atria. However, there is a need for accurate mapping and localization of these sources during catheter ablation.MethodsA novel AF source area probability (ASAP) mapping algorithm was developed and evaluated in 2D and 3D atrial simulated tissues with various arrhythmia scenarios and a retrospective study with three cases of clinical human AF. The ASAP mapping analyzes the electrograms collected from a multipole diagnostic catheter that is commonly used during catheter ablation procedure to intelligently sample the atria and delineate the trajectory path of a meandering repeating-pattern AF source. ASAP starts by placing the diagnostic catheter at an arbitrary location in the atria. It analyzes the recorded bipolar electrograms to build an ASAP map over the atrium anatomy and suggests an optimal location for the subsequent catheter location. ASAP then determines from the constructed ASAP map if an AF source has been delineated. If so, the catheter navigation is stopped and the algorithm provides the area of the AF source. Otherwise, the catheter is navigated to the suggested location, and the process is continued until an AF-source area is delineated.ResultsASAP delineated the AF source in over 95% of the simulated human AF cases within less than eight catheter placements regardless of the initial catheter placement. The success of ASAP in the clinical AF was confirmed by the ablation outcomes and the electrogram patterns at the delineated area.ConclusionOur analysis indicates the potential of the ASAP mapping to provide accurate information about the area of the meandering repeating-pattern AF sources as AF ablation targets for effective AF termination. Our algorithm could improve the success of AF catheter ablation therapy by locating and subsequently targeting patient-specific and repeating-pattern AF sources inside the atria.

Catheter-based renal denervation as adjunct to pulmonary vein isolation for treatment of atrial fibrillation: a systematic review and meta-analysis.

Renal denervation (RDN) can reduce sympathetic activity and blood pressure (BP) in hypertensive patients, which both have an impact on atrial fibrillation. We performed a systematic meta-analysis on the effects of renal denervation (RDN) in addition to pulmonary vein isolation (PVI) in patients with atrial fibrillation. All published randomized controlled trials investigating the effects of RDN as adjunctive treatment to PVI for rhythm control of atrial fibrillation were included. Primary endpoint was recurrence of atrial fibrillation after 12 months on average. A total of six randomized controlled studies including 689 patients with hypertension and symptomatic atrial fibrillation were included. In five studies, patients had uncontrolled BP despite prescription of an average of three antihypertensive agents. PVI was performed with irrigated radio-frequency catheters in 387 patients, and in 302 with cryoballoon. Cardiac ablation catheters were used for RDN in 78% of all cases. In the remaining 22%, RDN was performed using a designated, nonirrigated radio-frequency catheter system. After 12 months, the mean odds ratio for recurrence of atrial fibrillation for PVI with RDN compared with PVI alone was 0.43 (95% confidence interval 0.32-0.59). After RDN, BP was reduced significantly whereas no changes were reported in the PVI-only groups. No relevant complications associated to RDN were documented. This meta-analysis supports the concept of RDN as an adjunctive treatment for atrial fibrillation. Further studies with standardized PVI and RDN procedures are needed.

In silico analysis of the relation between conventional and high-power short-duration RF ablation settings and resulting lesion metrics.

Use of lesion metric indices is a proposed strategy to support pulmonary vein isolation procedures and these indices show good correlations with lesion sizes. The aim of this in silico study is to provide a detailed analysis of radiofrequency (RF) settings, including high-power short-duration (HPSD) settings, and resulting lesion metric indices. A software program was designed which simulated virtual RF ablations. Lesion metric indices (Ablation index: AI, Lesion size index: LSI) were calculated based on underlying RF settings (contact force [CF], power, duration). In series of calculations, the applied settings were varied within defined ranges (CF: 1-80 g, power: 1-60 W, duration: 1-60 seconds). Overall, n = 388 000 virtual ablations were calculated. The resulting lesion metric indices were compared with each other and analyzed in relation to respective RF settings. Increasing contact force from 1 to 10 g resulted in a 4.4-fold LSI value, whilst increasing contact force from 10 to 20g resulted in a 1.5-fold value (P < .01). When RF power was increased by 10 W, lesion metric indices increased between 1.3- and 1.6-fold. A prolongation of RF duration by 10 seconds resulted in a 1.2-to-1.3-fold increase of lesion metric indices. HPSD RF applications of 50 W, 11 to 13 seconds, and 60 W, 8 to 10 seconds resulted in equivalent lesion metric indices when compared with 30 W, 30 seconds conventional ablations. The findings support the clinical use of contact forces within a 10 to 20 g range. AI is more sensitive to RF duration, whereas LSI is more sensitive to contact force. HPSD RF settings can successfully be derived from lesion metric indices.

Sex-specific efficacy and safety of cryoballoon versus radiofrequency ablation for atrial fibrillation: An individual patient data meta-analysis

Atrial fibrillation (AF) is a growing health burden, and pulmonary vein isolation (PVI) using cryoballoon (CB) or radiofrequency (RF) represents an attractive therapeutic option. Sex-specific differences in the epidemiology, pathophysiology, and clinical presentation of AF and PVI are recognized. We aimed at comparing the efficacy, safety, and procedural characteristics of CB and RF in women and men undergoing a first PVI procedure. We searched for randomized controlled trials and prospective observational studies comparing CB and RF ablation with at least 1 year of follow-up. After merging individual patient data from 18 data sets, we investigated the sex-specific (procedure failure defined as recurrence of atrial arrhythmia, reablation, and reinitiation of antiarrhythmic medication), safety (periprocedural complications), and procedural characteristics of CB vs RF using Kaplan-Meier and multilevel models. From the 18 studies, 4840 men and 1979 women were analyzed. An analysis stratified by sex correcting for several covariates showed a better efficacy of CB in men (hazard ratio for recurrence 0.88; 95% confidence interval 0.78-0.98, P = .02) but not in women (hazard ratio 0.98; 95% confidence interval 0.83-1.16; P = .82). For women and men, the energy source had no influence on the occurrence of at least 1 complication. For both sexes, the procedure time was significantly shorter with CB (-22.5 minutes for women and -27.1 minutes for men). CB is associated with less long-term failures in men. A better understanding of AF-causal sex-specific mechanisms and refinements in CB technologies could lead to higher success rates in women.

Cryoablation for atrial fibrillation.

Cryoballoon ablation for the treatment of atrial fibrillation has established itself as an effective and efficient modality for achieving pulmonary vein isolation. Over the past 13 years more than 100,000 Cryoballoon ablation procedures have been performed with the first to fourth generation cryoballoons. Over that time there have been significant advances in our understanding regarding the optimal procedural techniques. The purpose of this "topic in review" is to focus on the practical aspects of performing a Cryoballoon ablation procedure, within the context of the contemporary literature. Specifically there is a focus on how contemporary studies can inform clinical decision making and ensure operators are able to perform a safe and effective procedure.

Cardiac Tamponade after catheter ablation for atrial fibrillation in a patient with complete situs inversus and dextrocardia

Complete situs inversus is a congenital condition which involves complete transposition of all thoracic and abdominal organs. This condition poses a technically challenging issue for the procedure of transcatheter pulmonary vein isolation to treat atrial fibrillation. We have recently experienced one case of situs inversus complicated with cardiac tamponade after successful ablation. The patient is a 67-year-old woman with a history of situs inversus totalis. She presented to our emergency department with repeated episodes of drug-resistant paroxysmal atrial fibrillation. Radiofrequency ablation was preferred. During the procedure, we performed interatrial septal puncture under intracardiac ultrasound guidance and isolation of all 4 pulmonary veins was achieved. Ten minutes after removing the sheaths from left atrium the patient developed cardiac tamponade and prompt pericardiocentesis was needed. Pericardial effusion resolved on the next day and she was discharged 3 days later. No recurrence of atrial fibrillation has been documented after the procedure. Judging from clinical progress, pericardial effusion is speculated to occur after removal of the sheath.

Renal denervation: can we press the "ON" button again in 2020?

In December 2018, an article summarizing available results of randomized studies on renal denervation (RDN), entitled “Renal denervation: can we press the ON button again?” was published in the Advances in Interventional Cardiology. Since then, several positive reports, including SPYRAL HTN OFF-MED Pivotal trial have been presented. In the current review the authors discuss the latest data on RDN in arterial hypertension treatment and try to answer the burning question: can we press the ON button again in 2020? The results of recently published studies potentially justify new recommendations for the use of RDN in clinical practice in appropriately selected patients in the new hypertension guidelines. The current review also summarizes the results of trials on RDN applied in another potential indication – atrial fibrillation. Six most important, prospective, randomized trials assessing RDN as adjunct therapy to pulmonary vein isolation for treatment of atrial fibrillation were discussed. In 5 studies, patients had uncontrolled BP despite treatment with three antihypertensive agents. The ratio for recurrence of atrial fibrillation for pulmonary vein isolation with RDN procedure was reduced by 57% as compared to pulmonary vein isolation (PVI) alone. BP was also reduced significantly after RDN in this subset of patients. Further multicenter studies involving standardized PVI and RDN procedures are needed.

Cryoballoon pulmonary vein isolation as a standard approach for interventional treatment of atrial fibrillation. A review and a practical guide to an effective and safe procedure.

Since the cryoballoon was introduced into clinical practice, approximately half a million patients have undergone a pulmonary vein isolation (PVI) using this tool throughout the world. This single-shot technique makes the pulmonary vein isolation procedure easier and has the potential to expand access to the interventional treatment of atrial fibrillation (AF), eventually leading to a reduction of the AF-related disease burden. Several studies and metanalyses have assessed the acute and long-term efficacy of cryoballoon-based PVI. The reported success rate of PV isolation during the procedure is about 98%. Despite this, the long-term effectiveness of the procedure (AF free survival) assessed at 1 year after the ablation is in the range of 70–82%. The AF-free survival rate significantly depends on the clinical characteristics of the studied group and the presence of risk factors, especially the type of AF (paroxysmal vs. persistent), LA size and the presence of heart failure. For a safe and effective procedure the electrophysiologist should be aware of all minute details of the procedure including several tricks developed by the most experienced operators and the pre-procedural and post-procedural management recommendations. Detailed knowledge of complications of cryoballoon (CB)-based ablation is mandatory. This review concentrates on the practical aspects and recommendations for a cryoballoon ablation procedure. The review is based on the authors’ experience, including 800 procedures performed over 11 years with a low complication rate, and is presented within the context of the literature.

Is the Time of Atrial Fibrillation Recurrence After Duty-Cycled Radiofrequency Ablation Affected by the Pattern of Pulmonary Vein Reconnections?

BackgroundPulmonary vein isolation (PVI) with multielectrode duty-cycled radiofrequency (PVAC) has been shown to be effective in the treatment of atrial fibrillation (AF). We describe pulmonary vein (PV) reconnection at repeat ablation in patients with AF recurrence after PVAC PVI and analyze the correlation between the time of AF recurrence and the observed PV reconnection patterns.MethodsEighty-five patients undergoing a redo PVI for recurrent AF 9.2 ± 3.8 months after an initial PVAC PVI procedure was retrospectively enrolled.ResultsA total of 93% had PV reconnections with a mean of 2.97 ± 1.2 reconnected PVs/patients and 75% of formerly isolated PVs were found reconnected. The highest reconnection rates (94%) were observed for left common trunks (CTs). A total of 33% patients had three and four reconnected PVs, respectively, while 7% were without PV reconnection. There was a moderate but significant negative correlation between the time of AF recurrences and the extending of PV reconnections at redo PVI for patients with proven PV reconnection (r = -0.32, P = 0.005), whereas five out of six patients without PV reconnection had recurrences within the first 9 months after PVI.ConclusionsAt redo ablation most patients with recurrence of AF after PVAC PVI had PV reconnection(s). Patients with PV reconnection(s) showed a moderate negative correlation between the number of reconnected PVs and the time of AF recurrence with more extensive PV reconnections resulting in earlier PV recurrences after the blanking period. Patients without PV reconnection experienced early AF recurrences, indicating non-PV triggers contribute to AF recurrences in these patients.

Ultrasound guidance for femoral venous access in electrophysiology procedures\u2014systematic review and meta-analysis

PurposeThe most common complications of electrophysiology (EP) procedures are related to vascular access. Our study aims to conduct a meta-analysis comparing ultrasound (US)-guided vs. palpation-based technique for femoral venous access in EP procedures.MethodsElectronic databases were searched and systematically reviewed for studies comparing femoral vein puncture with/without US in EP procedures. The primary outcome was the rate of major vascular complications; secondary outcomes were minor vascular complications, inadvertent artery puncture, postprocedural groin pain, and puncture time. Predefined subgroup analysis was conducted separately for patients undergoing pulmonary vein isolation procedure (PVI). A random-effects model was used to derive risk ratios (RR) with 95% confidence interval (CI).ResultsNine studies involving 8232 patients met our inclusion criteria. Compared with the standard technique, the use of US reduced major vascular complications (from 2.01 to 0.71%, p < 0.0001). The rate of minor vascular complications (RR = 0.30, 95% CI, 0.14–0.62, p = 0.001) and inadvertent artery puncture were lower with US-guided puncture (RR = 0.31, 95% CI, 0.17–0.58, p = 0.0003). Puncture time was shorter (mean difference = − 92.1 s, 95% CI, − 142.12 – − 42.07 s, p = 0.0003) and postprocedural groin pain was less frequent (RR = 0.57, 95% CI, 0.41–0.79, p = 0.0008) in the US group. Subgroup analysis of patients undergoing PVI also showed significant reduction of major vascular complications (RR = 0.27, 95% CI, 0.12–0.64, p = 0.003) and inadvertent artery puncture (RR = 0.35, 95% CI, 0.21–0.59, p < 0.0001).ConclusionReal-time US-guidance of femoral vein puncture in EP procedures is beneficial: it reduces major and minor vascular complications, inadvertent artery puncture, postprocedural groin pain, and puncture time.