bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development and internal-external validation of a prediction model for premature ventricular contraction unresponsive to the medical treatment
Authors: Atici A , Tanboga H İ , Barman H A , Sahin İ , Baycan Ö , Kup A , Celik M , Demirkiran A , Cevik E , Soysal A U , Karaduman M , Yilmaz İ , Yilmaz Y , Caliskan M , Aras D 
Published: November 2023

Abstract

Background
Ventricular premature contractions (PVCs) are the most common ventricular arrhythmias. However, to date, no risk stratification tool exists to assess response to medical therapy in patients with frequent PVCs (&gt;5% per 24 hours). We aimed to develop and validate a clinical prediction model evaluating response to medical therapy in frequent PVCs.

Methods
We conducted a retrospective cohort study of patients with frequent PVCs who were considered for medical treatment. The study outcome was unresponsiveness to the medical treatment (24-hour PVC count not diminishing by at least 80%) in patients with frequent PVCs at 3-6 months follow-up. Potential predictors were, age (years), PVC burden (%), LVEF % (&lt;55, ³55), PVC QRS width (msec), mean heart rate (beat/min), sinus beat QTc (msec), PVC coupling interval, gender, presence of multifocal PVC and Non-sustained VT. Binary logistic regression analyses were performed to develop and internally validate the model. Finally, we used internal-external cross validation using leave-one-out center.

Results
1644 patients were included in the study (mean age 52.2±13.5 years and 56.3% male). The frequency of unresponsiveness to the medical treatment in patients with frequent PVC was 31.2% (n=513). In the model, PVC burden (%), LVEF% (&lt;55, ³55) and PVC QRS width were found to be the three strongest predictors. The apparent and internal validation discriminations of the model (C-statistics in internal validation 0.910) were quite satisfactory. Model discriminations and calibration metrics with internal-external cross validation were similar to the apparent model and were deemed acceptable (https://demonoreflow.shinyapps.io/dynnomapp/).

Conclusions
We developed and validated a model that accurately predicts unresponsiveness to medical treatment in patients with frequent PVC. Our model, once externally validated, has the potential to facilitate management decisions by providing individualized risk estimates in patients with frequent PVC for whom ablation may be suggested as a first line treatment modality.Figure-1Figure-2
Early ICD implantation and survival after out-of-hospital cardiac arrest
Authors: Myredal A , Rawshani A R A Z , Sultanian P E D R A M 
Published: November 2023

Abstract

Background
It is unclear whether an implantable cardioverter-defibrillator (ICD) is generally beneficial in survivors of out-of-hospital cardiac arrest (OHCA) of cardiac etiology.

Aim
We studied the association between ICD implantation and survival in patients with cardiac etiology or initial shockable rhythm in OHCA, using the Swedish Registry for Cardiopulmonary Resuscitation (SRCR).

Methods
All cases in the SRCR during 2010 to 2020 with cardiac etiology or initial shockable rhythm who were discharged alive included. We examined the association between ICD and survival using propensity score. Propensity scores (919 candidate predictors before feature selection) were estimated using gradient boosting, Bayesian additive regression trees, neural networks, extreme gradient boosting and logistic regression. Cox regression was used to model survival. The primary outcome was death or recurrent cardiac arrest.

Results
The 90-days event rate was 25% in the ICD group, compared with 52% in those without ICD. With regards to the average treatment effect (ATE) the overall hazard ratio 0.38 (95% CI 0.26-0.56) for ICD vs. no ICD. The overall average treatment effect on those treated (ATT) was 0.31 (95% CI 0.22-0.44). In the 15 subgroup analyses, every point estimate were below 1, with the most pronounced association noted in those with a history of acute myocardial infarction (HR 0.07 [95% CI 0.02-0.32]). All ATE and ATE estimates were aligned.

Conclusions
Mortality in survivors of OHCA occurs early after discharge, and prompt implantation of an ICD is associated with 62% lower probability of death and recurrent cardiac arrest overall.
Neurohormonal status is associated with long-term appropriate implantable cardioverter defibrillator therapy for life-threatening ventricular arrhythmia
Authors: Beygui F , Roule V , Guedeney P , Werner T , Zeitouni M , Ollitraut P , Silvain J , Alexandre J , Collet J P , Milliez P , Montalescot G 
Published: November 2023

Abstract

Background
Neurohormonal status is associated with the risk of life-threatening ventricular arrhythmia.

Purpose
We aimed to assess whether neurohormonal status in patients with an implantable cardioverter defibrillator (ICD) is correlated with the risk of long-term appropriate shock or overdrive delivered by the ICD for life-threatening arrhythmia.

Methods
A total of 331 clinically stable patients with ICD without any past history of shock or overdrive for life-threatening ventricular arrhythmia were enrolled in a two-center prospective cohort and followed up for a median time of 7.9 years. At enrolment, patients’ medical history, treatment, clinical and imaging data were recorded and, blood and, blood samples were drawn for the assessment of standard biological parameters as well as 3 neurohormones (aldosterone, A type NT-pro-Atrial natriuretic peptide (ANP) and MR-pro-Adrenomedullin (ADM).
The primary endpoint of the study was the occurrence of appropriate shock or overdrive delivered by the ICD (ICD therapy).
A multivariable cox model adjusted on age, gender, primary or secondary prevention ICD as well as all baseline variables unequally distributed between groups with or without ICD therapy was used for the assessment of the relationship between the 3 neurohormones and the primary endpoint.

Results
The population consisted of patients with a mean age of 60±15 years, among which 59(18%) women and 160(48%) with a secondary prevention indication for ICD. At baseline all data were similar between patients with or without ICD therapy with the exception of weight, systolic blood pressure, left ventricular ejection fraction (LVEF) and serum potassium and creatinine levels. No other variable, including MADIT and SHOCKED score were significantly associated with the risk of ICD therapy.
Death was recorded in 114(34%) patients and a total of 78(24%), 76(23%) and 106(33%) patients had appropriate shock, overdrive and ICD therapy respectively during the follow-up.
On multivariable analysis, highest levels of ANP and lowest levels of ADM but not aldosterone were independently associated with life-threatening ventricular arrhythmia requiring ICD therapy (table). Other correlates of ICD therapy were lower LVEF and, higher weight, serum potassium and creatinine concentrations. ANP and ADM had a stepwise additive impact on the risk of ICD therapy. (Figure 1)

Conclusions
In a stable all comer population with ICD and no history of ICD therapy, blood levels of neurohormones ANP and ADM are associated with the risk of life-threatening ventricular arrhythmia requiring ICD-delivered shock or overdrive independent of other correlates. ANP and ADM concentrations may be useful in identifying patients at high risk of such arrhythmia and who may most benefit from ICD implantation.
Mortality benefit of implantable cardioverter-defibrillators for primary prevention of sudden cardiac death: a real-world analysis
Authors: Auricchio A , Ahmed A , Mittal S , Pickett R A , Wilkoff B L , Jacobsen L , Marti A K , Soderland D M , Curtis A B 
Published: November 2023

Abstract

Background
Nearly 1,000 people suffer an out-of-hospital sudden cardiac arrest daily in the United States, with only 10% surviving when treated by emergency medical services. Implantable cardioverter-defibrillators (ICDs) are a proven first-line treatment in limiting sudden cardiac death, but the evidence has become dated. We sought to assess the survival benefit of ICDs in a contemporary population.

Purpose
Using a real-world database, we aimed to determine the current impact of ICDs on mortality in primary prevention patients.

Methods
Data were obtained from a de-identified electronic health record database. We included patients that met ICD primary prevention indication (PPI) implantation criteria between 2012 and 2019, had one year of available data before the PPI, and survived for at least one year post-PPI. Patients were split into 2 groups based on ICD implant status (implanted vs not implanted) within one year after PPI. The primary endpoint was the overall mortality rate, beginning at one-year post-PPI. Propensity matching was performed to account for baseline differences between patients that did and did not receive an ICD, and all-cause mortality rates were compared using the Kaplan-Meier method and Cox proportional hazard model.

Results
A total of 25,296 patients were identified as having a PPI for ICD implantation, of which 2,118 (8.4%) were implanted with an ICD within a year. Implanted patients were younger than non-implanted patients (63.4 vs 66.1 years) and had a smaller proportion of females (25.0% vs 36.7%). After 4 to 1 propensity matching, patients who did not have an ICD implanted had a mean age of 63.6 years and were 25.1% female. In the matched cohort, the 5-year all-cause mortality rate was 37.6% (CI: 33.2%-41.7%) in PPI patients who received an ICD and 44.9% (CI: 42.8%-47.0%) in those that did not receive an ICD. A Cox proportional hazard model revealed a 25.3% lower risk of all-cause mortality in PPI patients implanted with an ICD compared to PPI patients without an ICD (HR: 0.747; CI: 0.670-0.834; p&lt;0.001 [Figure 1]).

Conclusion
In a large cohort of PPI patients that survived at least one year after indication, those implanted with an ICD during that year had a 25.3% lower risk of all-cause mortality than similar patients who did not receive an ICD, consistent with landmark trials. Thus, ICD implantation continues to be associated with a reduction in all-cause mortality in PPI patients at risk for sudden cardiac death.
Assessing the benefit of a replacement implantable cardioverter-defibrillator device for primary prevention of sudden cardiac death
Authors: Auricchio A , Curtis A B , Mittal S , Pickett R A , Jacobsen L , Lande J D , Wilkoff B L 
Published: November 2023

Abstract

Background
Implantable cardioverter-defibrillators (ICDs) have been shown to reduce the burden of sudden cardiac death in at-risk populations. However, data reflecting contemporary device programming and medication would be valuable, particularly when evaluating patients for a replacement ICD when they did not receive therapy from their original device.

Purpose
This real-world analysis examined the incidence of ICD therapy after routine generator replacement due to battery depletion in patients who didn’t receive therapy from their first ICD.

Methods
Data were obtained from a query of a deidentified database from 2007 to present. The final analysis included patients that underwent a generator replacement after 2012 due to battery depletion and who had received no therapy from their first ICD. Patients were divided into two groups based on their ICD indication status (primary prevention [PP] or secondary prevention [SP]). The main endpoint was time to first appropriate shock therapy, antitachycardia pacing (ATP) therapy, or any therapy (ATP or shock) after ICD replacement. Time to first therapy was plotted using the Kaplan-Meier method. Appropriateness of therapy was modeled via LASSO regression using characteristics present in both our dataset and the adjudicated PainFree SST trial. The model was fit on episodes from 80% of PainFree SST patients and validated on the remaining 20% before applying it to our dataset.

Results
A total of 8,383 patients were identified who met the criteria outlined above. Of these patients, 7,299 (66.3 ± 12.6 years old; 30.3% female) had a PP indication for an ICD and 1,084 (64.2 ± 14.0 years old; 30.3% female) had an SP indication. The mean longevity of initial ICD implants before replacement was similar in PP and SP patients (91.4 ± 16.2 vs 90.9 ± 16.3 months). At 7 years post-replacement, the incidence of first shock, ATP, or any therapy received by PP patients who did not receive first-device therapy was 16%, 23% and 27% respectively. After applying the model to estimate appropriateness of therapy, the appropriate therapy rates were 14%, 22%, and 26%, respectively (Figure 1). Similarly, SP patients who received no first-device therapy had an incidence of modeled first appropriate shock, ATP, and any therapy 7 years after ICD replacement of 12%, 20%, and 25%, respectively. The modeled 7-year inappropriate shock rate post-replacement was 4% in all patients.

Conclusion
In this large, long-term, real-world evaluation of ICD PP patients who hadn’t experienced a treated event with their initial device, 1 in 4 eventually received appropriate therapy from their second device. The results suggest that the underlying risk persists in these patients and device replacement may be necessary to protect them from experiencing a deadly event.
Comparison of two commercially available cryoballoon ablation systems
Authors: Diofano F , Pflieger C , Teumer Y , Bothner C , Rottbauer W , Dahme T , Weinmann K 
Published: November 2023

Abstract

Background
Cryoballoon pulmonary vein isolation (PVI) is an established anatomical single-shot procedure for the treatment of atrial fibrillation (AF).

Purpose
We compared efficiency of two commercially available cryoballoon ablation systems (CBS) to treat AF.

Methods
We prospectively enrolled 121 consecutive AF patients and treated them with either a compliant or a non-compliant CBS.

Results
Evaluation of procedural characteristics revealed a significantly longer procedure duration (p=0.007) and fluoroscopy time (p=0.008) in the group of the compliant CBS. The nadir cryoballoon temperature was lower using the compliant system compared to the non-compliant CBS (p&lt;0.0001), likewise the time to isolation was not different between both groups. The non-compliant CBS showed a better occlusion for the right superior pulmonary vein (RSPV, p=0.039) leading to a higher rate of isolation with first freeze (p=0.004) and lower number of ablations at the RSPV (p=0.015).
A mean follow-up period of 310.8±189.7 days within a 90-day blanking period. 68% of patients treated with the non-compliant and 65% of patients treated with the compliant CBS showed freedom from atrial arrhythmia recurrence (p=0.724). Kaplan-Meier estimation showed no significant difference between both groups (LogRank p=0.768).

Conclusion
The novel compliant CBS showed a longer procedure duration and fluoroscopy time, as well as, a lower nadir cryoballoon temperature. The non-compliant CBS was more effective in isolation of the RSPV. Acute PVI success and long-term freedom from atrial arrhythmia recurrence after a mean follow-up of ten months did not differ between groups.
Low voltage and low wave speed are rarely present outside the left atrium-pulmonary veins junction in paroxysmal atrial fibrillation but frequently present in persistent forms
Authors: Parreira L , Silva J , Marinheiro R , Mesquita D , Amador P , Farinha J , Chambel D , Encarnacao C , Contreiras P , Lopes C , Duarte L , Lopes J , Valcovo A , Caria R 
Published: November 2023

Abstract

Background and aim
Multielectrode high-density catheters have enabled acquisition of comprehensive and dense maps of electrogram’s amplitude and timing. However, automated activation and voltage mapping are flawed by catheter orientation in relation to the wavefront activation. Omnipolar mapping technology (OT) uses both unipolar and bipolar signals to obtain OT signals and increases the accuracy of automatic point acquisition allowing for a high- density map in a quick and efficient way. The aim of this study was to automatically assess with OT, the left atrium (LA) voltage and wave speed propagation map in sinus rhythm (SR) according to the type of atrial fibrillation (AF).

Methods
We studied 14 consecutive patients referred for ablation of AF, either paroxysmal (PAF) (n=6) or persistent (Pers-AF) (n=8) using catheters with OT. Patients with Pers-AF were cardioverted, and a SR map was obtained before ablation in all patients and voltage and propagation wave speed maps were obtained. The cut-off for low voltage areas (LVAs) was less than 0.1 mV and for low wave speed (LWS) was less than 0.4 mm/ms. Results were compared according to the type of AF.

Results
The results are depicted in the Table. The median duration of AF in Pers-AF was 18 (5-24) months. Patients with Pers-AF had larger LA volumes and displayed presence of LVAs and LWS areas in 100% of cases in comparison with 17% and 33% of cases respectively for PAF patients (p=0.003 and p=0.015). Also, the total LVAs and LWS areas in cm2 were significantly higher, (p=0.001 and p=0.005)). The LVAs and the LWS areas were more frequently located outside the PV-LA junction in Pers-AF than in PAF, respectively 75% vs 0% and 88% vs 0%, p=0.010 and p=0.005 (Figure).

Conclusions
Patients with PAF never presented LVAs or LWS outside the PV-LA junction. On the contrary, patients with Pers-AF had frequently anatomical and electrophysiological abnormalities in the LA body. These findings may suggest the need for a wider ablation strategy in Pers-AF.Normal voltage in purple ; LWS in white
Pulmonary vein isolation versus PVI + adjunctive strategy (substrate modification and renal denervation therapy) for the reduction of 12-month AF recurrence
Authors: Cabrera J , Ozaeta K , Hung P , Tiongco R , Bailon D 
Published: November 2023

Abstract

Background of the Study
This meta-analysis assessed the latest evidence on the use of adjunct ablation strategies to standard pulmonary vein isolation (PVI) for treating atrial fibrillation (AF). Adjunct treatments were further classified as substrate modification (posterior wall isolation, linear ablation and ablation of complex fractionated atrial electrograms) or renal denervation (RDN).

Purpose
While ablation maintains sinus rhythm more effectively than antiarrhythmic drug therapy, recurrent AF remains common after 12 months, occurring in up to 40-60% of patients undergoing standard PVI ablation. Treatment strategies have diversified in a response to these challenges. These include reduction of the arrhythmogenic substrate, modulation of autonomic inputs and improvement of risk factors, such as hypertension.

Methods
A systematic literature search from MEDLINE and PubMed electronic databases was performed until November 2022. The primary outcome was 12-month AF recurrence defined as AF lasting ≥30 seconds on follow-up. The secondary outcome was incidence of procedure-related major adverse events (MAEs), defined as death, clinical strokes, acute heart failure decompensation, pericardial effusion causing tamponade, arteriovenous fistulas, and atrioesophageal fistulas.

Results
Nine studies comprising 1686 patients were included in the final analysis. AF recurrence was 487/1082 (45%) in the PVI + Adjunct group and 204/604 (33.8%) in PVI Alone. Pooled analysis showed that PVI + adjunct was inconclusively associated with less incidence of 12-month AF recurrence (RR 0.79, 95% CI 0.60–1.04, I2 = 70%, p-value 0.09). Subgroup analyses of six RCTs under the PVI with substrate modification arm showed non-significant increase in 12-month AF recurrence in PVI + substrate modification (RR 0.85, 95% CI 0.6-1.21, p-value 0.38). Subgroup analyses of the 3 RCTs on hypertensive AF patients showed strong evidence of decreased 12-month AF recurrence in PVI + RDN compared to PVI alone (RR 0.65, 95% CI 0.48-0.89, p-value 0.007). Secondary outcome of major adverse procedure-related events in overall pooled analysis showed 8 events in 604 patients undergoing PVI alone, and 23 events in 1082 patients undergoing PVI + adjunct ablation. There is no significant difference in the number of reported MAE in PVI alone over PVI + adjunct (RR 1.16 [0.49-2.75], p = 0.73).

Conclusion
Overall, PVI with adjunctive strategies did not significantly reduce 12-month AF recurrence after ablation. Among these strategies, RDN demonstrated a significant reduction in the primary endpoint, whereas substrate modification did not. There was no significant difference in MAEs reported between standard therapy versus those with adjunctive treatment. We conclude that PVI ablation strategies should be individualized, and modification of both triggers and risk factors for AF show better rhythm control on follow-up.
Efficiency and safety in AF ablation using a novel loop-shaped cryoablation catheter
Authors: Hovhannisyan G , Hamann J , Dawid M , Payo A L , Quick S , Ibrahim K , Christoph M 
Published: November 2023

Abstract

Background
Different single shot ablation systems are under development to improve the efficiency and safety of pulmonary vein isolation for the treatment of atrial fibrillation (AF).

Purpose
Evaluation of effectiveness and safety of a novel cryoloop catheter (figure 1) for pulmonary vein isolation.

Methods
In a single centre prospective registry, patients with drug-refactory AF underwent pulmonary vein isolation (PVI) using a novel loop-shaped cryoablation catheter. For efficiency assessment the following parameters were registered: 1: the number of successfully isolated pulmonary veins (PV) confirmed by entrance- and exit block; 2: total procedure time, left atrial dwell time, total cryoablation time and applications as well as total fluoroscopy time; 3: freedom from atrial arrhythmia after 6 months. For safety assessment the following parameters were studied: 1: periinterventional adverse events like pericardial effusion, thromboembolic events and bleedings according to BARC classification; 2: endoscopic detected esophageal lesions (EDEL); 3: phrenic nerve palsy; 4: computed tomography angiography (CTA) detected PV stenosis until 6 months after PVI.

Results
In total, 25 subjects were enrolled in the current registry and received PVI with the loop-shaped cryoablation catheter. In terms of efficiency, successful acute PVI could be achieved in 91/100 treated PVs. Total procedure, atrial dwell, cryoablation and total fluoroscopy times were 130.5 ± 24.2 min, 101.4 ± 19.8 min, 40.8 ± 11.0 min and 22.5 ± 5.5 min, respectively. On average, 4.5 cryoenergy applications per PV were required for acute PVI. Out of the blanking period of 3 months, after 6 months 18/25 subjects (72%) were free from any atrial arrhythmia. With respect to safety, no pericardial effusion, thromboembolic event or bleeding complication occurred. 2/25 subjects experienced a transient phrenic nerve palsy. Additionally, no EDEL or PV stenosis could be detected.

Conclusion
The present single centre registry confirmed the effectiveness and safety of the novel loop-shaped cryoablation catheter for the treatment of atrial fibrillation.Figure 1: cryoloop catheter