bluuebunny/crossref_metadata_2025_split huggingface dataset:
Automatic left atrial segmentation from cardiac CT using computer graphics imaging and deep learning
Authors: Feng R , Deb B , Ganesan P , Rogers A J , Ruiperez-Campillo S , Clopton P , Tjong F V , Chang H J , Rodrigo M , Zaharia M , Narayan S M 
Published: October 2022

Abstract

Introduction
Segmenting left atrial (LA) substructures, including the LA body, appendage (LAA), and pulmonary veins (PVs), from computed tomography (CT) is central to electroanatomic mapping for ablation and functional studies in patients with atrial fibrillation (AF). However, this process requires manual outlining which needs special training, is subjective, and is difficult to scale. Computer graphics imaging (CGI) has been applied in media, film, and computer-aided design to reliably segment complex structures using their basic geometric representations.

Purpose
We hypothesized that LA substructures can be “virtually” dissected using CGI to separate geometric contours of the “convex ellipsoid” LA, “tubular” PVs, and “conical” LAA. We further hypothesized that the results of virtual dissection can be used to train a deep learning (DL) model to segment raw CT scans.

Methods
First, a mathematical method based on CGI techniques – erosion and dilation – was developed to “virtually dissect” the convex LA body from the original concave shell in publicly available digital atria with diverse simulated morphologies (Fig. 1A). The PVs and LAA were then automatically revealed and labeled by a 3D subtraction approach. Second, we refined precise LA/PV/LAA boundaries by tuning hyper-parameters from N=5 patient shells (Fig. 1B). Third, we used virtual dissection to train a DL model to segment CTs in N=20 patient atria (Fig. 1C). Finally, we applied this pipeline to segment raw CTs in a validation cohort of N=105 patients (23.8% women, 63.8±10.3Y; Fig. 1D).

Results
Virtual dissection accurately identified LA/PV/LAA boundaries in the training set (Dice coefficients 89–98%). In the independent test cohort (N=105), this automated pipeline accurately segmented raw CTs with Dice 81–95% (Fig. 1D) compared to a panel of experts (p&lt;0.001).

Conclusion
CGI of basic cardiac geometry combined with deep learning in small datasets can accurately segment raw CT scans in large populations. This computational pipeline may automate and simplify cardiac image processing and ablation procedures, and could be applied to the ventricle or other organ systems for diverse therapeutic strategies or to train machine learning.

Funding Acknowledgement
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Institutes of Health
Deep vein thrombosis after leadless pacemaker implantation
Authors: Hayashi T , Shishido K S , Moriyama N M , Tobita K T , Murakami M M , Saito S S 
Published: October 2022

Abstract

Background
A leadless pacemaker has been used widely. The necessity of using large sheath (23 Fr) is one of the disadvantages of implanting leadless pacemaker. There are some reports about deep vein thrombosis (DVT)after leadless pacemaker, but the accurate number of DVT after leadless pacemaker implantation is unknown.

Method
This retrospective study analyzed patients who were implanted leadless pacemaker from January 2018 to August 2022. We included the patients who were conducted ultrasound for DVT both before and after leadless implantation. The primary endpoint was incidence of DVT by ultrasound one day after leadless pacemaker implantation in the leg where sheath was inserted.

Results
89 patients were included in this study. The mean age of this study was 86.2±7.4 years old and 88 patients (99%) were implanted leadless pacemaker from their right femoral vein. 49 patients (55%) took anticoagulant before leadless pacemaker implantation. About the primary endpoint, 12 patients (13.5%: 8 patients without anticoagulant and 4 patients with anticoagulant) had newly asymptomatic DVT. After the univariate analysis, patients with low body weight (OR: 0.90, CI: 0.83–0.98, p=0.011), short height (OR: 0.87, CI: 0.79–0.96, p=0.005) and small diameter of the femoral vein (OR: 0.65, CI: 0.46–0.92, p=0.015) tended to have DVT. The use of anticoagulant did not affect the incidence of DVT (OR: 0.365, CI: 0.10–1.3, p=0.114).

Conclusion
Asymptomatic DVT by ultrasound is found in 13.5% of patients after leadless pacemaker. The small body patients might have easier to have DVT after leadless pacemaker. We should consider performing ultrasound to check for DVT in high-risk patients after leadless pacemaker implantation.

Funding Acknowledgement
Type of funding sources: None.
Mortality and 30-day readmission rate following leadless pacemaker implantation: insights from the Nationwide Readmissions Database
Authors: Tonegawa-Kuji R , Kanaoka K , Mori M , Nakai M , Iwanaga Y 
Published: October 2022

Abstract

Background
Clinical trials and registry data showed encouraging outcomes for leadless pacemaker (LP) implantation. However, reports of patient characteristics, trends, and clinical outcomes in a real-world population are limited.

Purpose
To provide real-world evidence of the rates, trends, and patient characteristics associated with in-hospital complications and 30-days readmission after LP implantations.

Methods
Using the all-payer, nationally representative Nationwide Readmissions Database between 2017 and 2019, we analyzed leadless or conventional pacemaker implantations. The national trends of in-hospital mortality, in-hospital complication rates and 30-day readmission rates after pacemaker implantation and their national trends were analyzed. Mixed-effects multivariable logistic regression analysis was performed to identify factors associated with in-hospital death and 30-days readmission in LP patients.

Results
A total of 137,732 admissions (age: 78 [70–85], 5,986 LP implantations) were analyzed (Figure 1). The in-hospital mortality, overall in-hospital complication rate, and 30-days readmission rates after LP implantations were 5.0%, 16%, and 16%, respectively. In LP recipients, the national estimate of in-hospital mortality declined from 10.9% in the second quarter of 2017 to 4.3% in the fourth quarter of 2019 (P&lt;0.001) (Figure 2a). Furthermore, the national estimate of overall complication rate declined from 20.6% in the second quarter of 2017 to 13.0% in the fourth quarter of 2019 (P&lt;0.001) (Figure 2b). Conversely, non-elective 30-day readmission rate did not show any increasing or decreasing trends in LP recipients (P=0.74) (Figure 2c). In LP recipients, female sex (odds ratio [OR] 1.42, 95% confidence interval [CI] 1.04–1.93), history of heart failure (OR 2.02, 95% CI 1.46–2.79), and first quartile annual pacemaker implantation hospital volume (OR 2.49, 95% CI 1.56–3.97, fourth quartile annual pacemaker implantation hospital volume used as a reference standard) were factors associated with in-hospital death.

Conclusions
Analysis of the nationally representative claims database in the US showed in-hospital mortality, complication rates, and non-elective 30-day readmission rate of 5.0%, 16%, and 16% respectively, for LP implantation performed during hospitalization. Although in-hospital mortality and complication rates showed a decreasing trend over time, ongoing surveillance is needed for the safety of LP implantation.

Funding Acknowledgement
Type of funding sources: Public hospital(s). Main funding source(s): Intramural research fund (21-6-9)for cardiovascular diseases of national cerebral and cardiovascular center.
3 Tesla magnetic resonance imaging in patients with cardiac electronic implantable devices: a single center experience
Authors: Nikorowitsch J , Tahir E , Erley J , Muellerleile K , Metzner A , Adam G , Blankenberg S , Kirchhof P , Toennis T , Fluschnik N 
Published: October 2022

Abstract

Background
Cardiac magnetic resonance imaging (MRI), a key method guiding medical diagnosis and therapy, is increasingly performed at 3 Tesla (T) field strength. Growing evidence suggests a relatively safe conductance of 1.5 T MRI in patients with cardiac implantable electronic devices (CIEDs), leading to conditional certification of some CIEDs for MRI. However, data on the safety of MRI imaging at 3 T in patients with CIEDs are scarce.

Purpose
We analysed the safety of clinically indicated 3 T MRI in patients with “3T MRI-conditional” and “3 T MRI-non-conditional” CIEDs.

Methods
We performed a retrospective single-center analysis of consecutive patients with CIEDs labelled by the manufacturer as “MRI non-conditional”, “1.5 T MRI-conditional” and “3 T MRI-conditional”. Patients underwent clinically indicated 3 T MRI of different thoracic and non-thoracic body regions from April 2020 to February 2022. Devices were interrogated and programmed appropriately before and after scanning. Statistics included median and interquartile range. Measurements of device and lead function and integrity before and after scanning were assessed. Adverse events included all-cause death, arrhythmias, loss of capture, inappropriate anti-tachycardia therapies, electrical reset and lead or generator failure during or shortly after MRI scan.

Results
One hundred twenty-eight 3 T MRI scans were performed in 94 patients (mean age 72±16 years, 36.2% female). 3T MRI scans were performed in patients with “non-MRI-conditional” devices (n=9), “1.5 T MRI-conditional” devices (n=22), and “3 T MRI-conditional” devices (n=97). Patients were pacemaker-dependent in 24 MRI scans. After MRI, lead impedance had changed by 100 Ohms or more in seven cases (4 atrial and 3 right ventricular leads). P-wave (−25%) reduction was noted in one, R-wave (−50%) reduction in two cases. Right atrial and ventricular threshold exceeded the limit of 0,5V in one case each only in “3 T MRI-conditional” devices. No clinically relevant adverse events occurred.

Conclusion
3 T MRI was safely conducted in patients with “3 T MRI-conditional” and “non-MRI conditional” CIEDs in our single-center study. Pending verification in independent series, our data suggest that clinically indicated 3T MRI scans should not be withheld from patients with cardiac pacemakers or defibrillators.

Funding Acknowledgement
Type of funding sources: None.
Subcutaneous Implantable Defibrillator programming: an analysis of Italian clinical practice and its evolution
Authors: Rordorf R , Viani S , Biffi M , Pieragnoli P , Nigro G , Migliore F , Francia P , De Filippo P , Dello Russo A , D'Onofrio A , Bisignani G , Ottaviano L , Caravati F , Valsecchi S , Vicentini A 
Published: October 2022

Abstract

Background
The UNTOUCHED study (designed in 2017 and published in 2021) demonstrated high success rate for termination of ventricular arrhythmias, and very low inappropriate shock rate in subcutaneous implantable cardioverter-defibrillator (S-ICD) recipients. The prescribed device programming included a conditional zone between 200 and 250 beats per minute (bpm) with discrimination algorithms employed to avoid delivering inappropriate shocks in this range, and a shock zone based on the rate alone for arrhythmias &gt;250 bpm. Whether these results influenced clinical practice is unknown.

Methods
We assessed the programming at implantation and changes in programmed parameters at follow-up (≥1 year) in a cohort of S-ICD recipients enrolled in the Rhythm Detect registry at 56 centers.

Results
From 2013 to 2021, 1521 consecutive patients (aged 49±15 years; 79% male, 52% dilated cardiomyopathy, 31% arrhythmic syndromes, 16% hypertrophic cardiomyopathy) were analyzed. At implantation, the programmed sensing vector was the Primary in 59% of patients, the Secondary in 35%, the Alternate in 6%. At follow-up, the sensed vector was changed in 13% of patients. The programmed conditional zone cutoff was set to 200 [200–220] bpm (median [25–75 percentile]), and the shock zone cutoff to 230 [210–250] bpm. At follow-up, the conditional zone cutoff was reprogrammed in 13% of patients, but the median value in the overall population did not change (200 [200–220] bpm; p&gt;0.05). The shock zone cutoff was reprogrammed in 43% of cases, and the overall median value was 250 [230–250] bpm (p&lt;0.001 versus implantation). Sorting patients by implantation date, we observed that in the first 764 patients (implanted ≤2017) the shock zone cutoff was set to 210 [210–230] bpm at implantation and to 240 [230–250] bpm at follow-up (reprogrammed in 66% of cases). While in patients implanted &gt;2017, it was already set to 250 [230–250] bpm at implantation and to 250 [240–250] bpm at follow-up (reprogrammed in 20% of cases, p&lt;0.001 versus ≤2017).

Conclusions
S-ICD programming parameters are rarely changed during follow-up (approximately 13% of patients). The only exception in clinical practice was the shock zone cutoff. Centers have begun to program high cutoffs in recent years. This happened at the time of implantation for new S-ICD recipients and at follow-up for pre-existing implants. This behavior is consistent with a substantial adoption of published trial findings and could contribute to reduce the incidence of inappropriate shocks in clinical practice.

Funding Acknowledgement
Type of funding sources: None.
Ventricular tachycardia ablation before an implantable cardioverter defibrillator in secondary prevention: is always the best option?
Authors: Martinho A , Almeida J , Antonio N , Elvas L , Goncalves L 
Published: October 2022

Abstract

Background
Among patients with an aborted episode of malignant ventricular arrhythmias without a reversible cause, the Implantable Cardioverter Defibrillator (ICD) is considered an important therapy for secondary prevention of sudden cardiac death (SCD). Some authors propose primary catheter ablation and deferred ICD implantation may be the preferred approach in patients with substrate-related ventricular tachycardia.

Purpose
We want to evaluate the need of secondary time ablation in patients with secondary prevention ICD, when submitted only a medical therapy after the index event.

Methods
We conducted a retrospective, observational study of 90 patients who consecutively implanted ICD after an aborted episode of malignant ventricular arrhythmias without a reversible/known cause between 2014 and 2020. Patients with Brugada Syndrome, Wolff-Parkinson-White syndrome, QT related diseases and previous ventricular tachycardia (VT) ablation were excluded. Baseline clinical characteristics were analyzed, and a 1-year follow-up was performed: cardiovascular (CV) death, sustain VT), ventricular fibrillation (VF), antitachycardia pacing (ATP), ICD shock, VT ablation.

Results
Mean age was 58±18 years, 80% (n=72) were male and 65.5% (n=59) had a non-ischemic etiology. Most of the patients (61%; n=56) present with hemodynamic unstable VT or syncope, and 38% (n=34) with SCD [most due to VF (n=30)]. After the index event 41.1% (n=37) and 83.8% (n=75) initiate antiarrhythmic and beta-blocker (BB), respectively. During 1-year follow-up (FUP) 11.1% (n=10) had a sustain VT and 2.2% (n=2) VF leading to ATP and appropriated shock in 11.1% (n=10) and 10% (n=9), respectively. There was 2 CV death [due to acute heart failure (HF)], 8 HF hospitalization and 3 VT ablation during follow-up. The presence of chronic kidney disease at baseline was the only parameter related to 1-year CV death (1.3% vs 18.2%, p=0.039) and HF hospitalization (0% vs 18.2%, p=0.014). The antiarrhythmic after index event was associated with a significant less sustain VT [10% vs 45%, OR 0.114 (IC 95% 0.014 to 0.927] and consequently ATP (adjusted for age) and had a numerical benefit in ICD shock (2.7% vs 15.1%, p=0.076) and need of a secondary time ablation (0% vs 5.7%, p=0.266).

Conclusion
The ICD implant with antiarrhythmic therapy, as a primary approach to secondary prevention (vs ablation), after an aborted episode of malignant ventricular arrhythmias still showed to be a secure and viable first option.

Funding Acknowledgement
Type of funding sources: None.
T-wave alternans poorly prognostic in primary prophylactic ICD patients: a prospective EU-CERT-ICD study
Authors: Pelli A , Junttila M J , Kentta T V , Schlogl S , Zabel M , Malik M , Reichlin T , Willems R , Vos M A , Harden M , Friede T , Sticherling C , Huikuri H 
Published: October 2022

Abstract

Background
New methods to identify patients who truly benefit from primary prophylactic implantable cardioverter defibrillation (ICD) are urgently needed. T-wave alternans (TWA) represents a beat-to-beat fluctuation in the morphology of the ST-segment and T-wave. It has been shown to associate with arrhythmogenesis of heart and sudden cardiac death [1]. We hypothised that TWA might associate with benefit from ICD implantation in primary prevention.

Methods
In EU-CERT-ICD study, we prospectively enrolled 2327 primary prophylactic ICD candidates from 15 European countries. A 24-hours Holter-monitoring was taken from all recruited patients at enrolment. TWA was assessed from Holter-monitoring using MMA method with Getemed Cardioday software. To assess the benefit from ICD treatment, we used outcomes all-cause mortality, appropriate shock and survival benefit. We conducted Cox regression model, competing risk regression model and propensity score adjusted Cox regression model. TWA was assessed both as contiguous variable and with cut-off points &lt;47 μV and &lt;60 μV.

Results
Final cohort included 1,734 valid T-wave alternans samples, 1,211 patients with ICD and 523 control patients with conservative treatment, with mean follow-up time 2.3 years. TWA &lt;60 μV predicted lower all-cause mortality in ICD patients in univariate cox regression model (HR 1.484, 95% CI 1.024–2.151, p=0.0374). In multivariate models, TWA did not predict death or appropriate shocks in ICD patients. In addition, TWA did not predict death in control patients. In propensity score adjusted Cox regression model, TWA did not predict ICD benefit.

Conclusion
T-wave alternans is poorly prognostic in primary prophylactic ICD patients. Altough it may predict life-threatening arrhythmias and sudden cardiac death in several patient populations, it cannot be used in assessing benefit from implantable cardioverter defibrillator in primary prevention among patients with ejection fraction ≤35%.

Funding Acknowledgement
Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Community's 7th Framework Program FP7/2007-2013
Intracardiac echocardiographically guided permanent pacemaker implantation is a feasible imaging tool with comparable procedural efficacy and safety
Authors: Shin S Y , Jung M , Byeon K , Kang K 
Published: October 2022

Abstract

Background
Amongst cardiovascular interventions, pacemaker implantation procedure is one of the most hazardous in terms of radiation exposure due to its proximity and unprotected radiation exposure. In order to reduce radiation hazards, alternative imaging tool to guide pacemaker implantation should be sought. The aim of this study is to investigate the feasibility, efficacy, and safety of intracardiac echocardiographically (ICE) guided pacemaker implantation.

Methods
We retrospectively investigated pacemaker implantation with ICE guidance. ICE catheter was placed in right atrium (RA). Right ventricular (RV) lead was placed in RV apex within home view (low RA, 2-4 O'clock). Then RA lead was placed in RA appendage within mid RA 1-2 O'clock view. Fluoroscopy was used only for verifying lead redundancy (2 or 3 second duration before pocket closure). Other procedure steps were similarly performed as in conventional fluoroscopic method. Radiation dosage, patient safety, total procedure time, and lead parameters were assessed and compared.

Results
From June 2013 to March 2021, a total of 270 patients underwent pacemaker implantation either with ICE or with fluoroscopy. Amongst them, ICE guided implantation was attempted in 35 patients. In order to exclude potential bias caused by the operator's learning curve, we excluded early 5 cases out of ICE group. Radiation exposure was markedly decreased within ICE group (2.3±4.4 Gy cm2 in ICE group vs. 27.2±50.5 Gy cm2 in fluoroscopy group, P&lt;0.001). The total procedure time and complication rate showed no significant difference between groups. In ICE group, atrial lead parameters were better than those of fluoroscopy group (impedance 454±57 Ω vs. 533±125 Ω, P&lt;0.001).

Conclusion
In 30 patients with ICE guided pacemaker implantation, radiation exposure was markedly decreased without any trade-offs in terms of patients' safety and procedural success. Furthermore, operation team members' physical stress reduction also might be potentially guaranteed.

Funding Acknowledgement
Type of funding sources: None.
The eligibility of patients with an inherited cardiac disease for therapy with a subcutaneous implantable cardioverter-defibrillator
Authors: Proost V M , Van Der Stuijt W , Pepplinkhuizen S , Knops R E , Wilde A A M 
Published: October 2022

Abstract

Introduction
The subcutaneous implantable cardioverter-defibrillator (S-ICD) is considered especially beneficial in young patients with an inherited cardiac disease, but data on these patient groups is limited.

Purpose
To evaluate the eligibility of patients with an inherited cardiac disease for therapy with a subcutaneous implantable cardioverter-defibrillator

Methods
We retrospectively analysed all patients with an inherited cardiac disease who received an S-ICD in our tertiary center between February 2009 and June 2021. ECG parameters and data on appropriate and inappropriate shocks were collected. Different diagnoses were compared using a chi-square test.

Results
We analysed 109 patients who were diagnosed with IVF (DPP6-based, N=41, 37.6%), HCM (N=36, 33.0%), Brugada syndrome (BrS, N=13, 11.9%), ARVC (N=9, 8.3%), PLN (N=3, 2.8%), LQTS (N=2, 1.8%) and other cardiomyopathies (N=5, 4.6%). Mean follow-up was 5.5±3.4 years. ECG parameters did not significantly change during follow-up. HCM patients were most likely to receive an appropriate shock (10/36, P=0.01), followed by ARVC (2/9, P=0.57) and Brugada patients (1/13, P=0.40). Patients with LQTS had most frequently inappropriate shocks (1/2, P=0.06), followed by BrS (4/13, P=0.008) and HCM patients (4/36, P=0.8).

Conclusion
Patients with an inherited cardiac disease are eligible for S-ICD therapy, but comes with a risk of inappropriate shocks, especially in patients with LQTS and BrS.

Funding Acknowledgement
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Dutch Heart Foundation (CVON 2018-10 PREDICT2)