bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kidney function by creatinine and cystatin c and adverse cardiovascular outcomes in patients with atrial fibrillation
Authors: Schweigler A , Hennings E , Aeschbacher S , Rodondi N , Stauber A , Moschovitis G , Bolt L , Mueller A , Coslovsky M , Meyer-Zuern C , Bonati L E O H , Conen D , Osswald S , Kuehne M , Krisai P 
Published: November 2023

Abstract

Background
Atrial fibrillation (AF) patients with chronic kidney disease are at an increased risk for ischemic and bleeding events and all-cause mortality. Accurate kidney function estimation is key for risk assessment. Creatinine is commonly used to calculate the Glomerular Filtration Rate (GFR). However, cystatin c has been described to be more sensitive than creatinine independent of muscle mass, autoimmune disease, inflammation or consuming diseases. Thus, cystatin C might be superior for risk assessment in patients with AF.

Aim
We aimed to investigate the associations between kidney function, assessed by creatinine and cystatin c, and major adverse cardiovascular events (MACE), its individual components, and major bleedings.

Methods
We enrolled 3865 AF patients into two prospective, multicenter cohort studies. Creatinine and cystatin c were measured at baseline and clinical outcome events were assessed yearly. We calculated GFR using the Chronic Kidney Disease Epidemiology Collaboration [CKD-EPI] formula based on either creatinine (GFRcr), cystatin c (GFRcy) or both (GFRc2). Primary outcome was MACE, defined as a composite of stroke or systemic embolism, myocardial infarction and cardiovascular death. Secondary outcomes were the individual components of MACE and major bleeding. Multivariable adjusted Cox regression analyses were built to investigate the associations between kidney function and adverse outcome events.

Results
Mean age was 71 ± 10 years and 28% were female. Mean creatinine and cystatin levels were 103 ± 32 μmol/l and 1.2 ± 0.4 mg/l, respectively, translating to a GFRc2 of 63.8 ± 21.7 ml/min/1.73 m2. Over a median follow-up of 6 years, the incidence rates for MACE (per 100 person-years) across quartiles (Q1-Q4) of GFRc2 were 22.0, 19.6, 17.4 and 15.9, respectively (Figure). When using multivariable adjusted Cox regression analysis, MACE was significantly associated with GFRcr (per 1 standard deviation: HR 0.87 (95%CI 0.77; 0.97) p=0.01), GFRcy (HR 0.68 (CI 0.58; 0.78), p&lt;0.001) and GFRc2 (HR 0.75 (CI 0.66; 0.86), p&lt;0.001). This association was mainly driven by cardiovascular death (Table). Major bleeding was associated with GFRcy (HR 0.73 (0.60-0.88) p=0.001) and GFRc2 (HR 0.80 (0.67-0.95), p=0.01), but not with GFRcr (HR 0.91 (95% CI 0.78-1.07) p=0.25).

Conclusion
Among AF patients, GFR equations including cystatin c were associated both with MACE and bleeding events, while creatinine based GFR equations were only associated with MACE. Therefore, Cystatin c based GFR equations might offer more comprehensive risk stratification in AF patients.Figure 1Table 1
Clinical characteristics and ablation outcomes of recurrent atrial tachyarrhythmia after maze operation -a multicenter study in a single city
Authors: Kawai S , Tanaka A , Sakamoto K , Inoue S , Nagaoka K , Okahara A , Tokutome M , Matsuura H , Takase S , Nozoe M , Tsutsui H , Mukai Y 
Published: November 2023

Abstract

Backgrounds
Catheter ablation of atrial tachyarrhythmia after Maze operation is challenging.

Methods and Results
Twenty-eight cases who underwent catheter ablation of post-Maze procedure atrial tachyarrhythmia (42 sessions; 1.5 per patient) in our 5 teaching affiliate hospitals were retrospectively analyzed. Cox-IV Maze procedure and left atrial Maze were performed in 19 cases and 5 cases, respectively. Median interval between surgery and index ablation was 35 months. In total, 46 atrial tachyarrhythmias were studied. Atrial tachycardia (AT) was the most common (n=36), whereas 4 atrial fibrillation (AF) and 2 focal AT were also observed. Identified tachyarrhythmia circuits were as follows; 16 mitral AT, 9 left atrial localized reentry (4 septal, 3 posterior, 1 left atrial appendage, 1 anterior), 6 right atrial lateral incision-related AT, 5 cavo-tricuspid isthmus (CTI)-dependent AT, 3 roof-dependent AT, 2 right atrial localized reentry (1 coronary sinus (CS), 1 CTI), 2 focal AT (1 para His, 1 CS), 1 bi-atrial AT, 1 pulmonary vein tachycardia, and 1 slow-fast AVNRT (Figure 1). Termination of targeted tachyarrhythmia was confirmed in 34 sessions (81%). AT/AF recurrence free rate at 12, 24, 36 months of follow-up were 91.8%, 81.6%, and 65.3%, respectively (Figure 2). Seven cases underwent multiple sessions (2 2nd sessions, 3 3rd sessions, 2 4th sessions). In these cases, de-novo atrial tachyarrhythmias were detected.

Conclusions
Most of the tachyarrhythmias after Maze operation were incision/gap-related ATs, among which mitral AT and LA localized reentry were the most prevalent. Although these challenging tachyarrhythmias can be treated with the contemporary mapping techniques, de-novo tachyarrhythmias can emerge in a remote period.Maze AT Figure 1Maze AT Figure 2
Transverse conduction across the crista terminalis with pseudo-focal activation pattern in patients with upper loop reentry atrial tachycardia
Authors: Ishihara T , Takasugi N , Tochibora R , Masuda Y , Sahashi Y , Naruse G , Watanabe T , Yamada Y , Kanamori H , Okura H 
Published: November 2023

Abstract

Background
Upper loop reentry (ULR) is a rare form of macroreentrant atrial tachycardia (AT) and an area of slow conduction exists in the crista terminalis (CT) where ablation is successful in eliminating the circuit. Transverse conduction across the CT during ULR AT has not yet been fully investigated.

Purpose
To investigate the transverse CT conduction during ULR AT

Methods
One hundred and five consecutive patients with macroreentrant AT were enrolled. The diagnosis of ULR was made based on endocardial activation mapping and entrainment pacing from multiple sites around the superior vena cava (SVC). Pseudo-focal pattern was defined as follows; (1) unsuccessful termination of ULR AT after extensive ablation along the CT and (2) distance from the earliest activation site (breakthrough) to the linear scar along the CT &gt;5 mm and a later activation site exists between the breakthrough and the CT.

Results
Nine (8.6%) of the 105 patients were diagnosed with ULR AT and studied. Seven (77.8%) of the ULR patients had a history of cardiac surgery or cavotricuspid isthmus ablation. Pseudo-focal pattern was observed in 4 (44.4%) patients who exhibited a linear scar along the CT connecting the SVC with the inferior vena cava. The median missing tachycardia cycle length (TCL) was 49.5 ms on the endocardial activation map. The median distance between the early-meets-late line (linear scar along the CT) and the breakthrough was 12 mm. RF application at the breakthrough successfully eliminated the ULR AT in all patients.

Conclusions
Nearly half of the patients with ULR AT exhibited pseudo-focal pattern suggesting a transverse conduction across the CT utilizing an epicardial connection such as the intercaval bundle. Ablating the breakthrough site is a better therapeutic option than ablating within the linear scar along the CT.Patient characteristicsRepresentative case
Pacemaker implantation after cardiac surgery: a contemporary analysis
Authors: Taha A , David A , Ragnarsson S , Szamlewski P , Jamaly S , Jeppsson A , Martinsson A 
Published: November 2023

Abstract

Background
Cardiac surgery entails an increased risk for bradyarrhythmias. Currently known rates for permanent pacemaker (PPM) implantation after cardiac surgery are derived from non-contemporary studies.

Purpose
We sought to explore the one-year incidence and indications for PPM implantation after different cardiac surgical procedures in the modern era.

Methods
All patients in Sweden from 2006 to 2020 who underwent first-time cardiac surgery without previous PPM or implantable cardioverter-defibrillator (ICD) were included in this nationwide population-based study using data from three national registries (SWEDEHEART, National Patient Registry and Swedish ICD & Pacemaker Registry). Patients who received an ICD (n=1,714) and patients undergoing heart transplantation (n=376) were excluded. Sex- and age-matched controls from the general population were used for comparison.

Results
A total number of 83,484 patients and 82,921 controls were included. Median follow-up was 6.3 years (range 0-15 years). A PPM was implanted in 8.0% (n= 6,707) of the patients, out of these 46.2% (n= 3,101) had pacemaker implanted during the first postoperative year. Atrioventricular block was the main indication in 1,988 (64.1%) of the patients and 1,113 (35.9%) received a PPM due to sinoatrial disease. The incidence rate per 100 patient-years for PPM implantation during the first postoperative year was 1.4 (95% confidence interval 1.3-1.5) for those who underwent coronary artery bypass grafting (CABG), 15.8 (14.6-18.4) following mitral valve surgery, 7.0 (6.6-7.5) after aortic valve surgery and 9.6 (8.6-10.3) for those with combined CABG and valve surgery. The median time from surgery to PPM implantation was 10 days (IQR 7 – 28, Figure 1A and Figure 1B). Compared to the control population, the risk for PPM implantation after cardiac surgery was higher even beyond the first post-operative year.

Conclusions
The need for PPM after cardiac surgery is highest during the first 30 postoperative days and mostly due to atrioventricular block. The incidence rate for PPM implantation after mitral valve surgery was higher than that following CABG, aortic valve, or combined CABG and/or valvular surgery.Figure 1AFigure 1B
The impact of sick sinus syndrome on flow velocity of the left atrial appendage in patients with atrial fibrillation
Authors: Takahashi S , Mine T , Fukuda Y , Yoshikawa F , Takai K , Iio C , Takada M , Fujita K , Nishibori Y , Maruyama T 
Published: November 2023

Abstract

Background
Sick sinus syndrome (SSS) itself has been suspected as one of potential embolic stroke sources, however, the mechanism remains unclear. Reduced flow velocity of left atrial appendage (LAAFV) plays a major role in thrombus formation in patients with atrial fibrillation (AF). We evaluated the contribution of SSS to LAAFV in patients with AF.

Methods
We studied 153 consecutive patients (age 69±10, 100 males, 79 paroxysmal AF, CHADS2 score 1.6±1.2) who underwent catheter ablation (CA) for AF at our hospital and our college of medicine. All patients enrolled in this study underwent transesophageal echocardiography (TEE) and transthoracic echocardiography prior to CA. LA global mean voltage and LA activation time were also measured using High-density LA mapping during CA. Clinical characteristics and laboratory data was obtained before CA for AF. SSS was defined as sinus arrest with 3 seconds or more by Holter ECG, or pacemaker implantation due to SSS.

Results
Reduced LAAFV was associated with old age (R²=0.0783, P=0.0005), female (R²=0.0260, P=0.0285), non-paroxysmal AF (R²=0.1403, P&lt;0.0001), hypertension (R²=0.0226, P=0.0338), history of congestive heart failure (R²=0.0890, P=0.0007), high CHADS2 score (R²=0.1248, P&lt;0.0001), high level of BNP (R²=0.2054, P&lt;0.0001), AF rhythm during TEE (R²=0.1577, P&lt;0.0001), low LV ejection fraction (R²=0.0255, P=0.0488), large LA diameter (R²=0.1544, P&lt;0.0001), high E wave (R²=0.1168, P&lt;0.0001), low LA global mean voltage (R²=0.1775, P&lt;0.0001), long LA activation time (R²=0.1383, P&lt;0.0001) and SSS (n=29, R²=0.0957, P=0.0002). On multiple linear regression analysis, SSS, AF rhythm during TEE, BNP, female was independently related to reduced LAAFV (Table).

Conclusion
SSS itself might be related to reduced LAAFV in patients with AF.Table
Eight year follow-up data on a leadless pacing system real life experience in comparison to data of the prospective trial
Authors: Winter S , Tuscher T , Nguyen D Q , Sinning J M 
Published: November 2023

Abstract

Introduction
The Micra™ leadless intracardiac pacing system has been introduced and implemented into clinical routine in 2015, with its next generation MICRA AV ™ in 2020. Feasibility, implantation safety, and acute success have been proven in the setting of controlled studies. Even apart from controlled studies, this new technology was beneficial for the individual patient. We aimed to report our single center follow-up (FU) data with a follow-up of up to six years.

Methods
In 272 patients (136 men; age: 81±5,7 y), Micra™ implantation was performed.
Pacemaker interrogation was performed one to seven days after implantation and during FU (1; 3; 6, then every 6 month) up to 84 months. Data were assessed in a real-life setting and compared with existing data of a controlled prospective trial.

Results
The implantation was successful in all 272 attempts with only one pericardial effusion as major complication. During follow up there were two patients developing severe heart failure symptoms resulting in an implantation of a CRT-device and switching of the leadless pacemaker system.
The average acute thresholds, sensing and impedance after system release were: 0.57±0.34V@0.24ms; 10,02±3,96mV and 752±1201Ohm. During follow up of up to 7 years neither, pacemaker failure, nor infections were reported. Measurements were reevaluated for long-term thresholds, sensing and impedance: 0.75 ± 0.38V @ 0.24 ms; 18,38 ±2,75 mV and 525 ± 102 Ohm. During seven years, no significant changes from acute to long-term measurements were detectable. In comparison to the controlled trial, our measurements of this real-life cohort were very similar.

Conclusion
In a real-life setting, the implantation of the leadless Micra™ system demonstrates a high rate of implantation success without major complications. We were also able to show stable long-term system parameters in the clinical setting of up to seven years of follow up with a very good battery longevity of about 12,3 years.
Aveir Leadless Pacemaker implantation in pediatric population: a case series
Authors: Masilamani M S J , Cortez D 
Published: November 2023

Abstract

Background
While the Medtronic Micra pacemaker provided a small device for leadless pacemaker implantation, the Aveir device allows chronic retrievability and mapping prior to fixation. We present the first Aveir leadless pacemaker implantations in a pediatric population.

Purpose
To describe the first retrievable leadless pacemaker implants in children.

Methods
Retrospective review of pediatric Aveir implants occurred between November 2022 and December 2022. All patients were implanted via internal jugular vein insertion utilizing the Aveir sheath and catheter deployment system with mid-atrial approach taken prior to insertion of the catheter across the tricuspid valve. All patients had initial mapping of capture threshold, impedance and R-wave noted prior to deployment. Indications for pacing included sinus pauses and intermittent atrioventricular block.

Results
Three patients underwent Aveir leadless pacemaker implantation with weights of 32.3kg, 44kg, and 51kg. Capture thresholds were all 0.75Volts@0.2 milliseconds with impedance range of 370-1110 ohms, and R-waves of 8-14 millivolts (mV). Follow-up at 3 months ranged from 0.5V@0.2ms to 1V@0.2ms with impedances ranging 400-700 ohms, and R-wave 7-14 mV. At VVI 50-55bpm, with pacing ranged from 5% to 14%, predicted longevities ranged from 20 to 24.5 years at 3 months follow-up.

Conclusion(s)
Retrievable leadless pacemaker implantation is feasible in children and may offer good longevities for intermittent pacing need.Aveir Leadless Pacemaker in RVAveir Leadless Pacemaker in RV
Impact of leadless pacemaker therapy on tricuspid regurgitation
Authors: Mendoza I M , Ukani Z , Rodriguez E R , Rangel A R 
Published: November 2023

Abstract

Background
The association between conventional transvenous pacemaker leads and tricuspid regurgitation (TR) has been well described. Leadless pacemakers (LP) have risen as an alternative to conventional transvenous pacemakers in order to avoid lead associated complications. Prior studies have included a mix of leadless pacemaker types including: Nanostim, Micra, etc. This is the first study exploring only one model of LP.

Purpose
The purpose of the study was to investigate the impact of leadless pacemaker therapy on tricuspid regurgitation.

Methods
Adult patients who underwent Micra leadless pacemaker implantation at a single center from 2016 to 2022 were identified retrospectively. Patients who had an echocardiogram prior to the procedure and within 24 months after the procedure were included. Echocardiograms were reviewed to assess for change in presence or in severity of tricuspid regurgitation.

Results
There were 310 patients in total who received LP at our hospital. Of these, 104 met inclusion criteria. 189 patients were excluded because they did not have an echocardiogram before or after the procedure. 17 more were excluded because their post procedure echo was done more than 2 years later. The average age of our patient population was 78. Of the 104 total patients, 97 had some TR before LP implantation (Trace 41%, Trace-Mild 4%, Mild 31%, Mild-Moderate 7%, Moderate 13%, Moderate-Severe 1%, Severe 2%). After implantation, 34 patients had worsening TR (33%), 23 patients had improved TR (22%), and 47 patients had no change in TR severity (45%) p=0.053.

Conclusion
Overall, the results did not show a statistically significant improvement or worsening in TR severity after LP implantation. Further studies should be done to validate these findings, to evaluate the effect of a larger sample size, and to examine whether controlling for additional confounders maintains or contradicts this finding.
Cardioneuroablation for symptomatic bradyarrhythmia: for whom it fails?
Authors: Wichterle D , Stiavnicky P , Jansova H , Peichl P , Stojadinovic P , Haskova J , Borisincova E , Cihak R , Kautzner J 
Published: November 2023

Abstract

Background
Cardioneuroablation (CNA) has been proposed as a new therapeutic approach in selected patients with symptomatic functional bradyarrhythmia including recurrent neurally-mediated syncope.

Purpose
In patients after CNA, we investigated the potential predictors of the recurrence of clinically significant bradyarrhythmia.

Methods
A retrospective study included 187 consecutive patients (age: 40±12 years; 57 % of males; predominant AV nodal phenotype of the disorder in 37 % of patients; post-atropine sinus rate acceleration by 72±31 %) who underwent their first CNA at our centre from 2014 to 2022 and were followed for the minimum of 3 months. Biatrial radiofrequency ablation was performed under general anaesthesia by irrigated-tip catheter at empirical sites of ganglionated plexi (GP) with the navigation by 3D electroanatomic mapping system and intracardiac echocardiography. Anterior right GP and posteromedial left GP were always targeted to modulate the innervation of both sinoatrial and atrioventricular nodes, irrespective of the clinical manifestation of the disease. The loss of responsiveness of both nodes to extracardiac vagus nerve stimulation (frequently bilateral) was the procedural endpoint. The association of baseline, procedural, and early follow-up characteristics with the recurrence of clinically significant bradyarrhythmia was analyzed.

Results
CNA with the procedural duration of 154±32 min and radiofrequency time of 14±7 min resulted acutely in sinus rate acceleration by 27±13 bpm, shortening of AH interval by 16±28 ms, an increase of Wenckebach point by 26±28 bpm, shortening of AV node effective refractory period by 114±128 ms, and sinus node recovery time by 462±867 ms. At the 3-month visit, the sinus rate was still significantly higher (83±14 bpm) than at baseline (61±13 bpm); with acceleration by 23±14 bpm. During a median follow up of 33 months (IQR: 18-48 months), recurrence of clinically significant bradyarrhythmia was documented in 18 (10 %) patients. Re-CNA was performed in 11 patients and was scheduled in 3 patients. In 6 (3 %) patients, a pacemaker was finally implanted. Compared to the rest of the population, patients with bradyarrhythmia recurrence were non-significantly younger (36±12 vs. 40±12 years, P=0.16) and had non-significantly less acceleration of sinus rate at the 3-month post-CNA visit (by 18±11 vs. 23±13 bpm, P=0.10) suggesting a trend to more pronounced reinnervation of the sinus node.

Conclusion
Long-term clinical efficacy of CNA is reasonably high. We did not identify practically useful predictors of CNA failure. This investigation was significantly limited by the low rate of clinical events.
Regional differences in extracellular volume increase arrhythmia vulnerability in aortic stenosis patients with and without diffuse fibrosis: a computational study
Authors: Sobota V , Augustin C M , Nordmeyer S , Vigmond E J , Bayer J D 
Published: November 2023

Abstract

Background
Extracellular volume (ECV) determined by magnetic resonance imaging (MRI) is considered a marker of myocardial fibrosis and a predictor of mortality. In addition to diffuse fibrosis, aortic stenosis (AS) patients present increased ECV. However, the impact of regional ECV differences on arrhythmia vulnerability in AS patients has not been assessed.

Purpose
To investigate regional ECV differences in AS patients and to determine their impact on ventricular arrhythmia vulnerability.

Methods
MRI was performed in 51 AS patients (32 males, 19 females) before and 3 months after aortic valve replacement (AVR). Regional differences in ECV were measured between mid-ventricular and basal planes. To investigate their impact on arrhythmia vulnerability, a computational biventricular model was developed from MRI data of the patient who presented the highest ECV difference between the planes in absence of a scar determined by late gadolinium enhancement (male 75y, post-AVR, ECV mid 25.5%, ECV base 31.3%, Figure A). The model was divided in two regions and extracellular conductivities (GE) were adjusted in each region as described previously (1), with additional GE reduction in the high ECV region representing increased interstitial fibrosis. This approach resulted in GE being 26.4% lower for ECV of 31.3% when compared to ECV of 25.5%. A model with uniform ECV of 25.5% was used as a control. Myocardial tissue was modelled with a cell radius of 16 micrometers, as reported in AS patients (2). The right ventricular apex was paced with S1=750 ms for 10 beats, followed by rapid pacing with different cycle lengths spanning the 20 ms window before the loss of stimulus capture to test arrhythmia inducibility. The simulations were repeated with an additional GE reduction by 30% and 60% in both regions to mimic conduction delays from diffuse fibrosis.

Results
Cardiac MRI showed significantly higher ECV in the basal plane of AS patients when compared to the mid-ventricular plane, both before and after AVR (Figure B), with the largest ECV found after AVR (mid-ventricular: p&lt;0.0001; basal: p=0.0011). No sex-specific differences were found. Simulations in the model with patient-derived ECV showed slightly longer QRS and lower CV than the model with uniform ECV (Table). By contrast, myocardial fibrosis had a larger impact on CV slowing. Arrhythmia was inducible when either diffuse fibrosis was present or ECV at the ventricular base was increased (Table).

Conclusion
Regional differences in ECV were found in the ventricles of AS patients. Computer simulations suggest that these differences have a minimal effect on ventricular conduction when compared to diffuse fibrosis. However, they might increase arrhythmia vulnerability even in the absence of diffuse fibrosis. Additional studies are necessary to investigate the effects of each on arrhythmia maintenance and cardiac mechanics.