bluuebunny/crossref_metadata_2025_split huggingface dataset:
Real world outcomes of minimally invasive epicardial surgical left atrial appendage exclusion in atrial fibrillation patients with high risk of stroke and bleeding
Authors: Friedman DANIEL , Rose DAVID , Calkins HUGH , Digiorgi PAUL , Ramlawi BASEL , Awasthi Y , Ferguson M , Pulugan Z , Tiegland C , Brennan M 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: Private company. Main funding source(s): AtriCure, Inc

Introduction
The left atrial appendage (LAA) is the site of thrombus formation in patients with atrial fibrillation (AF) and first line therapy for reducing the risk of stroke is oral anticoagulation (OACs). A subset of patients with AF carry a very high risk of stroke and bleeding and are ineligible for OAC and percutaneous LAA occlusion; these patients may be suitable for minimally invasive thoracoscopic epicardial surgical LAA exclusion (LAAE) which can be used with a wide variety of LAA morphologies with a ~98% rate of complete exclusion. While use of LAAE is well studied as a concomitant procedure, there are relatively few data on its use as a stand-alone procedure.

Purpose
To compare real-world outcomes of LAAE versus no-LAAE in AF patients at high risk of stroke and bleeding who are not on OACs.

Methods
We performed an analysis of Medicare beneficiaries with AF who were not on OACs and received LAAE (ICD10-PCS code 02L74CK, Oct 2015 – Dec 31, 2017) in the absence of a concomitant surgical or catheter AF ablation procedure. Patients were propensity-matched (1:4) to otherwise similar patients who did not receive LAAE (control), using age, gender, race, region, AF type, CHA2DS2-VASc, HAS-BLED, and co-morbidities. The primary endpoint was hospital readmission for a thromboembolic event (ischemic stroke, systemic embolism, or transient ischemic attack). Kaplan Meier event rates were calculated and 95% CI were generated via bootstrapping.

Results
A total of 243 patients who underwent LAAE and 1.7M control patients met study criteria. In the matched cohort, the mean age was 75 years, 61% were men, 77% had non-paroxysmal AF, and the mean CHADS2-VASC and HAS-BLED scores were 5.5 and 4.2, respectively. The 1-year rate of thromboembolism in the LAAE and control arms were 7.3% (95% CI 4.3% -10.9%) and 13.6 (95% CI 11.0% -16.4%) (Figure), respectively, with an absolute and relative risk reduction of 6.2% (95% CI 2.0-10.3, p-value=0.001, NNT 17) and 0.54 (95% CI 0.29-0.68, p=0.001).

Conclusion
Among high-risk AF patients who were not on OAC, LAAE was associated with a clinically meaningful and significantly lower risk of TE. Additional studies are needed to confirm these finding.
Multipolar pulsed-field ablation for the treatment of left atrial reentry tachycardia
Authors: Kueffer T , Seiler J , Madaffari A , Muehl A , Noti F , Haeberlin A , Servatius H , Tanner H , Baldinger S , Reichlin T , Roten L 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
A multipolar pulsed field ablation (PFA) catheter was recently introduced for pulmonary vein isolation and combines the benefits of high procedural efficacy and safety. It may also be used to treat left atrial (LA) reentry tachycardia.

Purpose
To describe our initial experience using a multipolar PFA catheter for the treatment of LA reentry tachycardia.

Methods
We included all patients with LA reentry tachycardia treated with a multipolar PFA catheter at our institution. Using 3D electro-anatomical mapping (3D-EAM), we identified the tachycardia mechanism and applied linear lesions either at the left atrial roof, mitral isthmus or on the anterior wall, as appropriate. Positioning of the PFA catheter was verified by integration into 3D-EAM. Applications were performed using 2.0kV with the catheter in basket or flower configuration, depending on ablation site. Bidirectional block across linear lesions was verified using standard criteria. Additional focal radiofrequency ablation (RFA) was used to achieve bidirectional block if necessary.

Results
We treated 17 LA reentry tachycardia with a multipolar PFA catheter in 13 patients (median age 69 (59-73) years; 5 females). The tachycardia mechanism was identified as roof-dependent in five, peri-mitral in eight and anterior scar-related in four cases. PFA lesion sets consisted of 12 posterior wall isolations (i.e. roof lines), four mitral isthmus lines (MIL) and eight anterior lines. For ablation of the mitral side of the anterior line, we always used the PFA catheter in basket configuration, while we targeted the posterior wall and the superior side of the anterior line exclusively with the catheter in flower configuration. To ablate the MIL we used both flower and basket configurations. Three roof-dependent, six peri-mitral, and four anterior scar-related tachycardias were successfully terminated by PFA (76%). Additional RFA was necessary for two MIL, two anterior lines and no roof line (17%). Finally, we achieved bidirectional block across all lines. PFA triggered, vagal-mediated and reversible AV block was observed in one case. Otherwise, there were no acute procedural complications.

Conclusion
Linear lesion sets are feasible and safe using a multipolar PFA catheter. Posterior wall isolation by PFA for the treatment of roof-dependent LA reentry tachycardia is highly efficient while anterior lines and MIL remain challenging and may need complementary RFA or a PFA catheter designed for focal or linear ablations.
Comparison of intracardiac echocardiography-guided versus conventionally performed cavotricuspidal isthmus ablation in patients with atrial flutter
Authors: Janosi K , Debreceni D , Turcsan M , Simor T , Kupo P 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Cavotricuspidal isthmus (CTI) is the target of the catheterablation for patients with typical atrial flutters. Intracardiac echocardiography (ICE) allows safe, real-time visualization of the anatomical structures thus can help reduce the use of fluoroscopy and improve procedural outcomes.

Purpose
We aimed to compare procedural and follow-up data of ICE vs. only-fluoroscopy guided procedures for CTI ablation in patients who underwent catheter ablation due to atrial flutter in our Institute.

Methods
154 consecutive patients were enrolled in our single-center retrospective study. In 70 patients, procedures were performed using fluoroscopy guidance only, while 84 patients underwent ICE-guided CTI ablation.

Results
ICE-guidance significantly reduced fluoroscopy time (137 ± 60.2 s vs 918 ± 609.5 s; p&lt;0.01), fluoroscopy dose (2.23 ± 1.44 mGy vs. 44.09 ± 25.23 mGy; p&lt;0.01) and total procedure time (67.6 ± 25.8 min vs. 79.6 ± 23.9 min; p&lt;0.01). Total ablation time (826 ± 445 s vs. 978.5 ± 676.8 s; p&lt;0.01) and the time from the first to last ablation (25 ± 14 min vs. 43 ± 26.5 min; p&lt;0.01) was also shorter in the ICE-guided group. Acute success rate was 100% and no major complications occurred in either group. Long-term success rate was 90.9% during the 2.13 ± 1.17 years follow-up period and did not differ between the groups (ICE-guided group: 94.1%, fluoroscopy-only group: 87.1%; p=0.14).

Conclusion
ICE-guidance for CTI ablation can significantly reduce fluoroscopy exposure, procedure time and ablation time compared to the traditional, fluoroscopy-only approach.
Long-term outcomes in patients with potential reversible causes of bradycardia
Authors: Passos M , Fialho I , Lopes J , Mateus C , Beringuilho M , Baltazar J , Santos M , Augusto J 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Hyperkalemia and negative chronotropic drugs are well known causes of reversible bradycardia. Their synergic combination may result in BRASH syndrome (Bradycardia, Renal failure, Atrioventricular blockade, Shock, and Hyperkalemia), a consequence of the vicious cycle between bradycardia, renal failure and worsening hyperkalemia, leading ultimately to multiorgan dysfunction. In potentially reversible bradycardia, drug discontinuation or metabolic correction is recommended before permanent pacemaker (PPM) implantation.

Objectives
To determine the long-term prognosis in patients with potentially reversible symptomatic bradycardia.

Methods
We retrospectively reviewed 176 patients who presented to the emergency department with symptomatic bradycardia, between January 2015 and August 2016. Patients without any reversible cause of bradycardia were excluded. Participants were stratified into three groups according to the reversible causes of bradycardia: patients with hyperkalemia, with or without acute renal injury (ARI) (group 1); patients taking negative chronotropic drugs, with or without ARI (group 2); patients with BRASH syndrome (combination of hyperkalemia and negative chronotropic drugs, with or without ARI) (group 3). The primary endpoint was PPM implantation after discharge. Secondary endpoints included: bradycardia-related rehospitalization, heart failure (HF) hospitalization, all-cause mortality and a composite of all the previous endpoints.

Results
A total of 105 patients were included (52.4% female; mean age 79.8±8.6 years). Group 1 was comprised by 15 patients (14.3%), group 2 by 69 patients (65.7%) and group 3 by 21 patients (20%, figure 1). The incidence of each event is presented in figure 2. During a mean follow-up of 3.2±2.1 years, PPM was implanted in 60 patients (57.1%) – 51 during hospital stay (85%) and 9 after discharge (15%). Across all groups, approximately 50% of the patients needed PPM implantation at some point, without significant differences between groups (p=0.508). Group 3 had the lowest need of in-hospital PPM (38.1%) but the highest bradycardia-related readmissions (9.5%). Nevertheless, post-discharge PPM implantation was still higher in group 1 (33.3%), followed by group 3 (22.2%). There were no significant differences in the post-discharge PPM implantation rate between groups (p=0.76). In groups 1 and 3 the composite endpoint (73.3% and 76.2%, respectively) was significantly more frequent than in group 2 (44.9%, p=0.046 and p=0.012, respectively).

Conclusions
Nearly half of the patients with an episode of reversible bradycardia needed a PPM at some point. Given the advanced age of most patients with bradycardia secondary to metabolic derangement and/or drug toxicity, it is possible that this unveils underlying conduction system disease, which is likely to recur without PPM implantation.
Heart rate acceleration during cardioneuroablation is a weak predictor of significantly reduced parasympathetic modulation of sinus node
Authors: Stiavnicky P , Wichterle D , Jansova H , Stojadinovic P , Haskova J , Peichl P , Cihak R , Kautzner J 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Ablation of superior parasympathetic ganglia is associated with acceleration of sinus rhythm (SR). This has been considered a favorable sign during cardioneuroablation (CNA) for the treatment of functional bradyarrhythmias.

Aim
We studied whether the relative increase in SR frequency (DeltaSR) during CNA is a reliable predictor of significantly reduced parasympathetic modulation of the sinus node (SAN).

Methods
In patients undergoing CNA under general anesthesia, the gradual reduction in parasympathetic modulation of SAN during the procedure was assessed by extracardiac right vagal nerve stimulation (ECVS). The response to ECVS was quantified by the ratio of the maximum P-P interval (induced by ECVS) and the baseline SR cycle length (MaxPPratio). The ECVS was performed repeatedly after partial ablation steps, and therefore several pairs of DeltaSR and MaxPPratio values were obtained in the course of the single procedure. A MaxPPratio &lt;1.5 was arbitrarily chosen as the criterion of significant attenuation of vagally induced responses. The optimum dichotomy of Delta-SR for the prediction of the MaxPPratio &lt;1.5 was found according to the criterion of the minimum distance of the ROC curve from the point (0; 1).

Results
The study included 64 patients (mean age: 42 ± 16 years, 48% men). A total of 188 intraprocedural pairs of DeltaSR and MaxPPratio (2.9 ± 2.1 pairs per procedure) covering the wide distribution of their values (19 ± 14 bpm for DeltaSR and 2.9 ± 2.8 for MaxPPratio) were obtained. One half of ECVS tests (51%) met the criterion of MaxPPratio &lt;1.5. In the analysis of receiver operating characteristic, DeltaSR as a predictor of significantly reduced parasympathetic modulation of SAN showed an area under the curve (AUC) of 0.69 with 95% confidence interval (CI) of 0.62 - 0.77 (Figure). The optimum cut-off (DeltaSR ≥20 bpm) had a sensitivity (SENS), specificity (SPEC), positive (PPV), and negative predictive value (NPV) of 61%, 78%, 75%, and 66%, respectively.

Conclusion
Acceleration of SR during CNA is not a relevant surrogate of significantly reduced parasympathetic modulation of SAN. Elimination or significant suppression of responses of SAN to ECVS serves as an excellent procedural endpoint that might contribute to the favorable clinical outcome of the CNA.
Optimal catheter-tissue contact value for ablation of ventricular arrythmias originating from the left ventricular papillary muscles
Authors: Baran J , Skrzynska M , Piotrowski R , Sikorska A , Krynski T , Kulakowski P 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Good catheter-tissue contact is mandatory to create effective ablation lesions. The minimal contact force (CF) value for successful ablation of arrhythmias originating from the left ventricle (LV) was reported at the 8-10 g level, however, optimal CF values for ablation of arrhythmias arising from papillary muscles (PM) are not known.

Purpose
To determine optimal CF value for ablation of arrhythmias from LV PM.

Methods
Twenty-four consecutive patients (mean age 57,9 ± 11,9 years, 16 males) who from May 2017 to June 2020 underwent ablation of premature ventricular complexes (PVC) originating from LV PM were included. The primary endpoints were an acute procedural success (total elimination of PVC) and long-term success (median 27 months). Ablation was performed with the use of the CARTO electro-anatomical system and intracardiac echocardiography (ICE).

Results
Acute success – complete abolition of PVC, was obtained in 23 (96%) patients. The fluoroscopy time was 3,9 ± 3,5 min and the procedure duration was 114,8 ± 38 min. The mean number of applications was 8,74 ± 6,78 and the mean application time - 518,5 ± 437,25 sec. The mean CF during successful ablations was 3,1 ± 1,5 g, with 3 ± 1,1 g and 3,18 ± 1,8 g for anterolateral and posteromedial PM, respectively (p= 0,809975). The mean CF during one unsuccessful ablation was 3 g. At control Holter ECG, the mean PVC burden in all patients was reduced from 28,36 ± 14,48 % to 2,42 ± 2 %: in the anterolateral PM group from 18 ± 8 % to 2,6 ± 2 % (p= 0,005415) and in the posteromedial PM group - from 34,8 ± 13,7 % to 1,7 ± 1,3 % (p= 0,012694). During long-term follow-up (median 27, IQR 17-34) there was one recurrence among 23 patients who had acutely successful procedures.

Conclusion
The values of CF for successful ablation of PVC originating from LV PM are lower than those for ablation in other parts of LV. The values slightly exceeding 3 g seem to be sufficient to achieve ablation success.
Long-term impact of activation circuit-based ventricular tachycardia ablation on ventricular arrhythmia burden
Authors: Freire Barbas De Albuquerque F , Portugal G , Silva Cunha P , Valente B , Lousinha A , Delgado AS , Paulo M , Rosa T , Bras M , Cruz Ferreira R , Oliveira M 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Ventricular arrhythmias (VA) are a major cause of morbidity and mortality in heart failure patients. Ventricular tachycardia (VT) ablation is an established treatment for the reduction of recurrent implantable cardioverter-defibrillator (ICD) therapies in this population. In patients with substrate-related VT, mapping of the entire tachycardia circuit, when feasible, may allow for more accurate targeting of the clinical VT.

Purpose
To assess the long-term impact of catheter ablation based on activation mapping of substrate-related VT on VA burden.

Methods
Consecutive patients submitted to VT ablation between January 2013 and October 2021 were included. A comprehensive review of clinical records and device monitoring was performed to assess VA burden, defined as all ICD therapies and clinically documented VTs, before and after ablation. The primary outcome was reduction in the overall burden of VA after ablation. The impact of ablation on VA burden was assessed by fixed-effects Poisson regression; comparison at fixed time intervals was performed with a paired-sample Wilcoxon signed-rank test (STATA 12, JASP).

Results
A total of 134 VT ablation procedures were performed during the study period. Of these, there were 21 procedures where complete mapping of the VT activation circuit was achieved, corresponding to 18 patients. Mean age was 56.7 years, 88% male sex, mean left ventricular ejection fraction 39 ± 13%, BNP 540 ± 627 pg/mL. Etiology was ischemic in 44%, non-ischemic dilated cardiomyopathy in 39%, arrhythmogenic right ventricular dysplasia in 11% and hypertrophic cardiomyopathy in 6%. Mechanical support was in situ in 3 patients (two with temporary VA ECMO and one with LVAD as destination therapy); all but one patient had an ICD. Procedural duration was 209 ± 61 minutes. One patient developed complete AV block; no other peri-procedural complications were observed. During follow-up two patients died due to heart failure, one patient died from refractory cardiogenic shock with refractory incessant VT and one patient underwent orthotopic heart transplant. The mean follow-up time after ablation was 2.2 ± 1.9 years. A significant reduction in VA burden was observed (Figure 1) at 3 months (92.5% reduction, p=0.002) and 6 months after ablation (83.3% reduction, p=0.041). After fixed-effects Poisson regression, there was an estimated long-term reduction of 75% (CI 12-93%, p=0.031) of VA burden after VT circuit ablation.

Conclusion
Targeted circuit ablation is feasible in a subset of patients referred to VT ablation and leads to a significant sustained decrease in VA burden and device therapies.
Establishing safe, effective ablation in the diseased human ventricle: an analysis of generator impedance and electrogram attenuation
Authors: Bates A , Paisey JR , Yue A , Banks P , Roberts PR , Ullah W 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: Private company. Main funding source(s): Biosense Webster Inc

Background
Predictors of effective and safe lesion delivery in the human left ventricle have not been established. Generator impedance (GI) drop and electrogram (EGM) attenuation are indices which can be used as surrogates for ablation lesion parameters. Tissue pops are a complication of myocardial overheating preceded by a rise in GI and can have adverse consequences.

Purpose
To establish the relationships between Ablation Index (AI), Force Time Integral (FTI) and contact force with GI and EGM attenuation. To establish factors early in ablation that are predictive of a GI rise.

Methods
Patients undergoing ventricular tachycardia ablation were recruited. All ablations were performed with contact force sensing surround flow catheters. Electrograms were collected pre and post ablation, with GI, AI, FTI measured during. Ablations were divided into low (LVM, &lt; 0.50mV), intermediate (IVM, 0.51 – 1.50mV) and normal voltage (NVM, &gt; 1.50mV) based upon pre-ablation bipolar EGM amplitude. Ablations with a 5% rise in GI from maximal drop were noted and predictors of this explored.

Results
In 15 patients, 402 ablations were analysed. Filtered percentage GI drop correlated with AI and FTI, (p &lt; 0.0005, Spearman’s ρ = 0.522 and 0.524) and reached a plateau at 763AI and 713gs, a filtered GI drop of 7.5% (Figure 1). Shallower curves occurred progressively from NVM to IVM to LVM, (p &lt; 0.0005), (Figure 2)
The bipolar EGM significantly attenuated with ablation, (median attenuation 0.14mV, [29.3%], p &lt;0.0005), but percentage attenuation did not correlate with AI or FTI.
Parameters associated with a GI rise during ablation were greater mean CF to maximum GI drop, (p = 0.002), greater initial percentage GI drop at 5 seconds, (p &lt; 0.0005), power of 50W (p = 0.005), and perpendicular orientation, (p = 0.006). Percentage GI drop at 5 seconds was the best predictor of ablations with a GI rise, (AUCROC 0.773; 95% CI 0.708 – 0.838; optimal cut-off 2.44%). Mean contact force to maximum GI drop was a poor predictor of a GI rise (AUCROC 0.647; 95% CI 0.577 – 0.718, optimal cut-off 14.7g).

Conclusion
During left ventricular ablation, AI of 763 and FTI of 713gs should be targeted, with a lower impedance drop observed for more scarred myocardium. A GI drop of &lt;2.5% at 5 seconds and contact force &lt; 15g should be used to optimise ablation safety.
Area weighted unipolar voltage to predict heart failure death in patients with ischemic cardiomyopathy and ventricular tachycardia
Authors: Rademaker R , Kimura Y , Beukers HC , Piers SR , Wijnmaalen AP , De Riva Silva M , Dekkers OM , Zeppenfeld K 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Patients with ischemic cardiomyopathy (ICM) referred for catheter ablation (CA) of ventricular tachycardia (VT) are at risk for end-stage heart failure (HF) due to adverse remodeling of the left ventricle (LV). Local unipolar voltages (UV) decrease with loss of viable myocardium. A UV mapping derived parameter that corrects for oversampling of the infarct area may reflect the total amount of remaining LV viable myocardium.

Objective
To evaluate if the newly proposed parameter, `area weighted unipolar voltage’ (awUV), can predict HF related death/LVAD/Heart transplant (HFD) in ICM.

Methods
Voltage maps from consecutive patients with ICM referred for CA of VT, were transferred to Paraview after valve area removal. AwUV was calculated by mathematically interpolating all mapping points weighted for relative distances divided by the LV endocardial surface. Unipolar low voltage areas (ULVA, UV&lt;8.27mV) were measured as percentage of the total LV surface. Associations between clinical and mapping derived parameters and HFD (HF-related death/LVAD/heart transplant) were evaluated and validated in a second cohort of consecutive patients.

Results
Eighty-nine patients in the study group (age 68±8; LVEF 33% [IQR 24-40%]; ULVA 64% [IQR 46-86%]; awUV 7.01 [IQR 5.01-8.52]) and 69 patients in the validation group (age 68±9; LVEF 39% [IQR 29-44%]; ULVA 59% [IQR 43-77%]; awUV 7.60 [IQR 6.16-8.69]) were included. Follow-up was 32±17 months in the study group, 28±17 months in the validation group. HFD was 20% in the study group, 10% in the validation cohort. Patients with HFD had lower LVEF and awUV, and larger ULVA than patients without HFD (LVEF 23±10% vs. 35±11%; awUV: 5.12±1.92 vs. 7.75±2.64; LVA 86±21% vs. 60±23%, all P&lt;0.001). Univariable analysis showed that LVEF, ULVA and awUV were associated with HFD (HR and 95% CI: LVEF 1.10 [1.05 – 1.16]; LVA 1.05 [1.02 – 1.08]; awUV 2.18 [1.58 – 3.40], all P&lt;0.01). AwUV was superior to ULVA to predict HFD in likelihood ratio calculations (awUV: LR 5.66, P=0.02; LVA: 1.76 P=0.18) and ROC analysis (AUC awUV: 0.86; LVA 0.78). The optimal cut-off for awUV of&lt;5.27 was highly accurate to predict HFD in the validation cohort (log-rank P&lt;0.001).

Conclusion
The newly proposed parameter awUV, easily available from routine voltage mapping, may be useful at identifying ICM patients at risk for HFD.