bluuebunny/crossref_metadata_2025 huggingface dataset:
Best constants of Banach-Stone type theorems in subgroups of 𝐶(𝐾)
Authors: Dong Yunbai , Leung Denny , Li Lei , Wang Liguang
Published: October 2021

Assume that

X
,
Y

X, Y

are compact Hausdorff spaces. Let

C
(
X

)
+

C(X)_+

,

C
(
Y

)
+

C(Y)_+

be the sets of all positive real functions on

X
,
Y

X,Y

respectively. Let

T
T

be a surjective map from a point separating multiplicative subgroup

G
⊂
C
(
X

)
+

G\subset C(X)_+

onto a point separating multiplicative subgroup

H
⊂
C
(
Y

)
+

H\subset C(Y)_+

satisfying

T
1
=
1

T1=1

and
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="StartFraction 1 Over upper M EndFraction double-vertical-bar f dot g Superscript negative 1 Baseline double-vertical-bar less-than-or-equal-to double-vertical-bar upper T f dot left-parenthesis upper T g right-parenthesis Superscript negative 1 Baseline double-vertical-bar less-than-or-equal-to upper M double-vertical-bar f dot g Superscript negative 1 Baseline double-vertical-bar">

1
M

‖
f
⋅

g

−
1

‖
≤
‖
T
f
⋅
(
T
g

)

−
1

‖
≤
M
‖
f
⋅

g

−
1

‖

\begin{equation*} \frac {1}{M}\|f\cdot g^{-1}\|\leq \|Tf\cdot (Tg)^{-1}\|\leq M \|f\cdot g^{-1}\| \end{equation*}

for all

f
,
g
∈
G

f, g\in G

and for some constant

M
≥
1

M\geq 1

. Then there exists a homeomorphism

τ
\tau

from the Šilov boundary

∂
H

\partial H

of

H
H

onto the Šilov boundary

∂
G

\partial G

of

G
G

such that
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="StartFraction f left-parenthesis tau left-parenthesis y right-parenthesis right-parenthesis Over upper M squared EndFraction less-than-or-equal-to left-parenthesis upper T f right-parenthesis left-parenthesis y right-parenthesis less-than-or-equal-to upper M squared dot f left-parenthesis tau left-parenthesis y right-parenthesis right-parenthesis">

f
(
τ
(
y
)
)

M
2

≤
(
T
f
)
(
y
)
≤

M
2

⋅
f
(
τ
(
y
)
)

\begin{equation*} \frac {f(\tau (y))}{M^2}\leq (Tf)(y)\leq M^2\cdot f(\tau (y)) \end{equation*}

for all

f
∈
G

f\in G

and all

y
∈
∂
H

y\in \partial H

. The constant

M
2

M^2

in the inequality above is optimal.

A similar argument yields a generalization of the classical Banach-Stone Theorem to isometries defined from an additive subgroup of

C
0

(
X
)

C_0(X)

into

C
0

(
Y
)

C_0(Y)

for locally compact Hausdorff spaces

X
X

and

Y
Y

.
Reducing Your Risk of Alzheimer’s Dementia: Building a Better Brain as We Age
Authors: Bennett David A
Published: October 2021

Alzheimer’ dementia is a large and growing public health problem. Of utmost importance for limiting the impact of the disease on society is the prevention of dementia, that is, delay onset either by years whereby death ensues prior to dementia onset. The Religious Orders Study and the Rush Memory and Aging Project are two harmonized cohort studies of aging and dementia that include organ donation at death. Ongoing since 1994 and 1997, respectively, we published on the association of numerous experiential, psychological, and medical risk factors for dementia, many of which are potentially modifiable. Here, selected findings are reviewed based on a presentation at the 2020 National Academy of Neuropsychology given virtually in Chicago in October of 2020.
Cloning of the cycloisomaltotetraose-forming enzymes using whole genome sequence analyses of Agreia sp. D1110 and Microbacterium trichothecenolyticum D2006
Authors: Fujita Akihiro , Kawashima Akira , Noguchi Yuji , Hirose Shuichi , Kitagawa Noriaki , Watanabe Hikaru , Mori Tetsuya , Nishimoto Tomoyuki , Aga Hajime , Ushio Shimpei , Yamamoto Koryu
Published: October 2021

We performed whole genome sequence analyses of Agreia sp. D1110 and Microbacterium trichothecenolyticum D2006 that secrete enzymes to produce cyclo-{→6)-α-d-Glcp-(1→6)-α-d-Glcp-(1→6)-α-d-Glcp-(1→6)-α-d-Glcp-(1→} (CI4) from dextran. Full-length amino acid sequences of CI4-forming enzymes were identified by matching known N-terminal amino acid sequences with products of the draft genome. Domain searches revealed that the CI4-forming enzymes are composed of Glycoside Hydrolase family 66 (GH66) domain, Carbohydrate Binding Module family 35 (CBM35) domain, and CBM13 domain, categorizing the CI4-forming enzymes in the GH66. Furthermore, the amino acid sequences of the two CI4-forming enzymes were 71% similar to each other and up to 51% similar to cycloisomaltooligosaccharide glucanotransferases (CITases) categorized in GH66. Differences in sequence between the CI4-forming enzymes and the CITases suggest mechanisms to produce specific cycloisomaltooligosaccharides, and whole genome sequence analyses identified a gene cluster whose gene products likely work in concert with the CI4-forming enzymes.
MoNET: an R package for multi-omic network analysis
Authors: Li Jin , Chen Feng , Liang Hong , Yan Jingwen
Published: October 2021

Motivation

The increasing availability of multi-omic data has enabled the discovery of disease biomarkers in different scales. Understanding the functional interaction between multi-omic biomarkers is becoming increasingly important due to its great potential for providing insights of the underlying molecular mechanism.

Results

Leveraging multiple biological network databases, we integrated the relationship between single nucleotide polymorphisms (SNPs), genes/proteins and metabolites, and developed an R package Multi-omic Network Explorer Tool (MoNET) for multi-omic network analysis. This new tool enables users to not only track down the interaction of SNPs/genes with metabolome level, but also trace back for the potential risk variants/regulators given altered genes/metabolites. MoNET is expected to advance our understanding of the multi-omic findings by unveiling their transomic interactions and is likely to generate new hypotheses for further validation.

Availability and implementation

The MoNET package is freely available on https://github.com/JW-Yan/MONET.

Supplementary information

Supplementary data are available at Bioinformatics online.
Prospective evaluation of the learning curve and electrical characteristics of left bundle branch area pacing
Authors: Heckman L I B , Luermans J G L M , Jastrzebski M , Stipdonk A M W , Westra S , Weijs B , Den Uijl D , Linz D , Mafi-Rad M , Prinzen F W , Vernooy K
Published: October 2021

Background

Left bundle branch area pacing (LBBAP) has recently been introduced as a physiological pacing technique with a synchronous ventricular activation.

Objective

To prospectively evaluate the feasibility and learning curve, as well as the electrical characteristics of LBBAP.

Methods

In 80 consecutive LBBAP pacemaker patients, ECG characteristics during intrinsic rhythm, RV septum pacing (RVSP) and LBBAP were evaluated. From the ECG's QRS duration and LVAT (stimulus to V6 R-wave peak time, RWPT) were measured. Also, the left bundle branch potential (LBBpot) to V6 RWPT interval was measured and compared to the LVAT. After conversion of the ECG into VCG (Kors conversion matrix), QRS area, as measurement for electrical dyssynchrony, was calculated.

Results

Permanent lead implantation was successful in 77/80 patients (96%) undergoing an attempt at LBBAP. LBBAP lead implantation time as well as fluoroscopy time were significantly shorter during last 25% of implantation compared to first 25% of implantations (17±5 min vs. 33±16 min and 12±7 min vs. 21±13 min, respectively, panel A and B). LBB capture was obtained in 54/80 patients (68%). In 36/45 patients (80%) with intact AV conduction and narrow QRS an LBBpot was present. The mean interval between the LBBpot and the onset of QRS was 22±6 ms.

In the patients with narrow QRS (n=45), QRS duration increased significantly during both RVSP (139±24 ms) and LBBAP (123±21 ms), compared to intrinsic rhythm (95±13 ms).

QRS area on the other hand, increased during both RVSP (73±20 μVs) but decreased during LBBAP (41±15 μVs), to values close to intrinsic rhythm (32±16 μVs, panel C). For all patients, QRS area was significantly lower in patients with LBB capture compared to patients without capture (43±18 μVs vs 54±21 μVs, respectively).

In patients with LBB capture (n=54), LVAT was significantly shorter compared to patients without LBB capture (75±14 vs. 88±9 ms, respectively). In the patients with LBB capture, there was a significant correlation between the LBBpot – V6 RWPT and S – V6 RWPT intervals (Pearson correlation 0.739, P<0.001).

Conclusion

LBBAP is a safe and feasible technique, with a clear learning curve that seems obtained after ± 40–60 implantations. LBB capture is obtained in two-thirds of patients. Although QRS duration remains prolonged, LBBAP largely restores ventricular electrical synchrony to values close to intrinsic (narrow QRS) rhythm.

Funding Acknowledgement

Type of funding sources: None.
Characteristics of patients with atrial high rate episodes detected by implanted defibrillator and resynchronisation devices
Authors: Miyazawa K , Pastori D , Martin D , Choucair W , Halperin J , Lip G
Published: October 2021

Aims

Atrial high rate episodes (AHRE) are associated with increased risks of thromboembolism and cardiovascular mortality. However, the clinical characteristics of patients developing AHRE of various durations are not well studied.

Methods

This was an ancillary analysis of the multicenter, randomized IMPACT trial. In the present analysis, we classified patients according to duration of AHRE ≤6 minutes, >6 minutes to ≤6 hours, >6 hours to ≤24 hours and >24 hours, and investigated the association between clinical factors and the development of each duration of AHRE.

Results

Of 2,718 patients included in the trial, 945 (34.8%) developed AHRE. The incidence rates of each AHRE duration category were 10.7, 24.0, 0.14, and 0.07%, respectively. Using Cox regression analysis, heart failure was inversely associated with AHRE <6 minutes (hazard ratio [HR] 0.58, 95% confidence interval [CI] 0.40–0.85, p=0.005), while age ≥65 years and history of atrial fibrillation (AF) and/or atrial flutter (AFL) were risk factors for AHRE >6 minutes. Female gender was inversely associated with AHRE >6 minutes to ≤6 hours (HR 0.72, 95% CI 0.54–0.96, p=0.027) and >6 hours to ≤24 hours (HR 0.70, 95% CI 0.49–1.02, p=0.061). Hypertension was associated with AHRE >24 hours (HR 2.13, 95% CI 1.24–3.65, p=0.006).

Conclusion

AHRE >6 minutes to ≤6 hours were most prevalent among all AHRE duration categories. Age and history of AF/AFL were risk factors for AHRE >6 minutes. Women were at lower risk for AHRE >6 minutes to ≤24 hours, while hypertension was associated with AHRE >24 hours.

Funding Acknowledgement

Type of funding sources: None. Cumulative incidence of each AHRE burden
External validation of H2ARDD score for the prediction of heart failure events in patients with atrial fibrillation
Authors: Taniguchi N , Miyasaka Y , Suwa Y , Harada S , Nakai E , Shiojima I
Published: October 2021

Background

Heart failure is an important consequence in patients with atrial fibrillation (AF) which is associated with worse prognosis. The H2ARDD score, calculated from 5 clinical risk factors, was reported as a predictor of heart failure events in patients with AF. However, this score has not been externally validated.

Purpose

The purpose of this study was to evaluate and validate the usefulness of the H2ARDD score for the prediction of heart failure events in AF patients.

Methods

We used prospective data of patients with AF followed up from 2007 to 2017 in our institute. Patients with active cancer were excluded according to the previous report. H2ARDD score was calculated as follows; history of heart disease=2 points, anemia=1 point, renal dysfunction=1 point, diabetes =1 point, diuretic use=1 point (range from 0 to 6 points). Outcome of interest was defined as heart failure events including new-onset heart failure and death with heart failure. Heart failure was ascertained based on the Framingham criteria. Univariable and multivariable Cox-proportional hazards model were used to assess the risk of heart failure events. Heart failure events-free survival was estimated with Kaplan-Meier methods, and the predictive accuracy of the H2ARDD score for the prediction of heart failure events was measured by the area under the receiver operating characteristic (ROC) curve.

Results

Of 562 AF patients, 522 (age 69±10 year–old, 64.9%men) met study criteria. Patients who had a history of heart disease was 185 (35%), diabetes mellitus was 135 (26%), anemia was 54 (10%), renal dysfunction was 221 (43%), and diuretic use was 193 (37%). The mean H2ARDD score was 1.88±1.57. Of all study patients, 84 (16.2%) developed heart failure events during a mean follow–up of 54±42 months. Patients who developed heart failure events in 1 year was 24 (4.6%). In multivariable Cox–proportional hazards model, H2ARDD score was shown as an significant predictor for heart failure events (hazard ratio: 1.56, 95% confidence interval: 1.36 - 1.79, P<0.0001), independently of age (per 10 years, hazard ratio: 1.35, 95% confidence interval: 1.03 – 1.78, P<0.05). In the Kaplan–Meier analyses stratified by H2ARDD score (0–1, 2–3, 4–6), patients who had a higher H2ARDD sore had significantly worse heart failure event-free survival (log-rank P<0.0001) (Figure 1). The area under the ROC curve for the prediction of heart failure events in 1-year was 0.812 (95% confidence interval: 0.737 – 0.887, P<0.0001), and the best cut-off value was ≥4 points (sensitivity: 67%, specificity: 83%) (Figure 2).

Conclusion

H2ARDD score was demonstrated as a significant independent predictor for the prediction of heart failure events, with high predictive accuracy. H2ARDD score may be useful for heart failure risk stratification of AF patients.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2
Digoxin vs. beta-blocker therapy in atrial fibrillation: analysis from the ESC-EHRA EORP Atrial Fibrillation General Long-Term (AFGen LT) Registry
Authors: Ding W.Y , Proietti M , Boriani G , Marin F , Blomstrom-Lundqvist C , Fauchier L , Potpara T.S , Lip G.Y.H
Published: October 2021

Background

There is a long-standing and unresolved controversy over the effects of digoxin on mortality. Furthermore, there is scarce evidence comparing the use of digoxin to beta-blocker in the general population with atrial fibrillation (AF). In this study, we aimed to evaluate the effects of digoxin over beta-blocker therapy among patients with AF.

Methods

Patients from the EORP-AF General Long-Term Registry with AF who were treated with either digoxin or beta-blocker were included. All patients were over 18 years old and had documented evidence of AF within 12 months prior to enrolment. The outcomes of interest were all-cause mortality, cardiovascular (CV) mortality, non-CV mortality and number of patients with unplanned hospitalisation (total and AF-related). These were recorded until the last known follow-up available.

Results

Of 6377 patients, 549 (8.6%) and 5828 (91.4%) were treated with digoxin and beta-blockers, respectively. Patients in the digoxin group were older (73 vs. 71 years, p<0.001) with reduced renal function (eGFR 65.4 vs. 68.7 mL/min/1.73m2, p=0.002), and had (in general) greater burden of comorbidities in terms of chronic kidney disease, chronic obstructive pulmonary disease, heart failure, hypertension and peripheral artery disease. Nonetheless, the use of anticoagulation therapy was comparable between both groups (p=0.112).

Over 24 months follow-up, there were 550 (8.6%) all-cause mortality and 1304 (23.6%) patients with unplanned emergency hospitalisation. Digoxin use was associated with increased all-cause mortality (hazard ratio [HR] 1.90 [95% CI, 1.48–2.44]), both from CV and non-CV causes (CV: HR 2.21 [95% CI, 1.49–3.26]); non-CV: HR 1.70 [95% CI, 1.04–2.79]). There was no statistical difference in terms of unplanned emergency hospitalisation (HR 0.99 [95% CI, 0.80–1.21]) and AF-related hospitalisation (HR 0.78 [95% CI, 0.58–1.06]) between both groups.

Using multivariable cox regression analysis, digoxin compared to beta-blocker therapy was independently linked to increased all-cause mortality (HR 1.52 [95% CI, 1.11–2.09]) and CV mortality (HR 1.82 [95% CI, 1.11–2.97]), but was not related to non-CV mortality (HR 1.31 [95% CI, 0.71–2.41]), emergency hospitalisation (HR 0.91 [95% CI, 0.71–1.16]) or AF-related hospitalisation (HR 0.88 [95% CI, 0.62–1.24]), after adjustment for known risk factors.

Conclusion

We demonstrated that the use of digoxin was independently associated with excess all-cause mortality, driven by CV death, but was non-inferior to beta-blocker in terms of preventing unplanned emergency or AF-related hospitalisation, after accounting for important risk factors.

Funding Acknowledgement

Type of funding sources: None.
Third-generation laser balloon ablation: rapid mode applicability is associated with shorter time to pulmonary vein isolation
Authors: Martignani C , Ziacchi M , Statuto G , Bartoli L , Spadotto A , Angeletti A , Massaro G , Diemberger I , Sorrentino S , Capobianco C , Giacopelli D , Bassini M , Grassini D , Galie N , Biffi M
Published: October 2021

Background

The rapid mode feature implemented in the latest version of the laser balloon system (LB3, HeartLight, X3, Cardiofocus) offers an automated continuous 360° lesion for pulmonary vein isolation (PVI). However, data on its clinical applicability and the potential reduction of procedural times are not yet available.

Purpose

To explore the use of the rapid mode and its association with PV total and fluoroscopy times in our initial experience with LB3.

Methods

This analysis included consecutive patients who underwent PVI procedure with LB3. We attempted to perform a complete circular ablation line using the rapid mode at 13 W, but if needed to achieve successful isolation, rapid mode was interrupted and manual mode (5.5–8.5 W) applications were used. The percentage of rapid mode use on the 360° lesion was measured for each PV. Total and fluoroscopy times to complete PVI were also collected.

Results

A total of 110 PVs were identified in 27 LB3 procedures and successfully isolated with a mean procedural time of 85±31 min. Sixty (55%) PVs were treated by using rapid mode for more than 50% (180°) lesion and 13 (12%) of them had a pure rapid mode ablation (without necessity of manual mode applications). Right inferior PV had the highest use of rapid mode (median value 70%). The main reasons for manual applications were poor PV occlusion, imperfect ostium visualization and presence of blood. PVs with >50% rapid mode use were treated in a significantly shorter time (21.2±13.7 vs 26.8±12.4, p=0.043). Fluoroscopy time did not differ significantly (4.7±4.2 vs 5.4±4.9, p=0.48). Three pinhole balloon ruptures were observed during rapid mode energy application in the second, third and twenty-fifth procedure. No other complications occurred.

Conclusions

Few PVs could be isolated using pure rapid mode; however, its applicability for more than 50% lesion was observed more frequently and significantly reduced the time to isolation.

Funding Acknowledgement

Type of funding sources: None. Time to isolation using Rapid Mode
10-year clinical outcomes after radiofrequency catheter ablation for atrial fibrillation. A single center experience
Authors: Alderete Martinez J.F , Shizuta S , Yoneda F , Nishiwaki S , Tanaka M , Komasa A , Kohjitani H , Yoshizawa T , Kimura T
Published: October 2021

Background

Radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) is becoming a routine procedure to treat patients with drug-refractory symptomatic AF. However, data regarding very long-term clinical outcomes is limited. The aim of the present study was to evaluate the 10-year clinical outcomes of patients who underwent RFCA for paroxysmal and persistent AF.

Methods

We retrospectively enrolled 503 consecutive patients (mean age 66,9±9,51 years; 71,6% male) who underwent RFCA for drug-refractory symptomatic AF between February 2004 and June 2011. Follow-up information was obtained using medical records and/or telephonic interviews with the patient, relatives and/or referring physicians.

Results

Among 503 patients enrolled in this study, 362 had paroxysmal atrial fibrillation (PAF) and 141 had persistent atrial fibrillation (PeAF) (72% and 28%, respectively). Mean follow-up was 8,84±3,05 years. The 10-year event-free rate for recurrent atrial tachyarrhythmia (AT) after the first procedure was 44,5% (49,4% for PAF vs 31,9% for PeAF; p=0,002 by log-rank test) and 81,9% after the last procedure (87,3% for PAF and 67,9% for PeAF; p≤0,001 by log-rank test). AT recurrence was observed most commonly during the first 12 months of the initial procedure (56%), with only 18% of them occurring after 60 months. Multivariate analysis revealed that persistent AF (hazard ratio=1,366; 95% confidence interval 1,058–1,76; p=0,017) and duration of AF >5 years (hazard ratio=1,357; 95% confidence interval 1,064–1,732; p=0,005) were independent risk factors for AT recurrence. Regarding adverse events, there were 24 (4,8%) hospitalizations for acute decompensated heart failure, 20 (4%) ischemic strokes and 14 (2,8%) bleeding complications requiring hospital admissions. Patients taking oral anticoagulation and antiarrhythmic drugs at the end of the study accounted for 32,8% and 16,7% respectively.

Conclusions

RFCA for AF provided favorable results in terms of arrhythmia event-free survival in long-term follow-up with better results in patients with paroxysmal AF. Persistent AF and long-standing AF (beyond 5 years) were associated with AT recurrence. Despite the large number of patients who discontinued oral anticoagulation, thromboembolic adverse events were rare.

Funding Acknowledgement

Type of funding sources: None.
Comparison of coronary flow reserve feasibility and values in different stress echocardiography protocols: dobutamine, dipyridamole, exercise and rapid pacing
Authors: Wierzbowska-Drabik K , Picano E , Cortigiani L , Kasprzak J.D
Published: October 2021

Background and aims

To compare the feasibility of Coronary Flow Velocity Reserve (CFVR) assessment in the left anterior descending (LAD) artery in four types of stress echocardiography (SE): dobutamine (DOB), dipyridamole (DIP), rapid pacing (PAC) and bicycle exercise (EXE).

Methods and results

We subjected 369 patients (mean age: 67±11 years) to SE with DOB (up to 40 mcg/kg/min, n=230), DIP (0.84 mg/kg, n=73), PAC (n=22) or EXE (n=44). CFVR was measured as the ratio of peak diastolic coronary flow velocity (CFV) during exercise, pharmacological stress or pacing and peak diastolic CFV at rest in distal or mid LAD.

The feasibility was excellent during PAC (100%), DOB (95%) and DIP (95%) and lower during EXE (73%, p<0.01 vs other groups) when assessed in all consecutive patients. When assessed in patients having readable LAD flow at rest the feasibility achieved even higher values, being however still lowered in EXE group, see Figure 1.

In multivariate analysis only the EXE protocol was a predictor of LAD flow loss during SE, with OR = 8.23 (95% CI 2.17 – 31.33), p=0.0019. CFVR was lower with PAC (1.8±0.4) as compared to DIP (2.2±0.6, p=0.0061) and DOB (2.2±0.6, p=0.0025), but similar to EXE (2.0±0.6, p=0.178), and correlated best with the peak heart rate in EXE and PAC, see Figure 2.

Conclusion

CFVR in LAD can be obtained during all forms of SE, but the feasibility is significantly higher with PAC and pharmacological tests as compared to EXE, which was identified in our study as the independent predictor of the loss of LAD flow recording at the peak of stress test. Moreover, CFVR values were the lowest in PAC group which however encompassed the older patients with more advanced coronary artery disease. Significant correlation between HR and CFVR observed in EXE and PAC suggests that in this type of SE cut-off value of CFVR should be probably indexed to maximal HR achieved.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2
Electrical anatomy of the left atrium during atrial fibrillation
Authors: Adragao P , Nascimento Matos D , Costa F , Galvao Santos P , Rodrigues G , Carmo J , Carmo P , Cavaco D , Morgado F , Mendes M
Published: October 2021

Introduction

Twenty years ago, pulmonary veins (PV) ostia were identified as the left atrium (LA) areas with the shortest refractory period during sinus rhythm. Pulmonary veins isolation (PVI) became standard of care, but clinical results are still suboptimal. Today, a special tool using the Carto® electroanatomical mapping (EAM) allows for AF cycle length mapping (CLM), to identify the areas in the left atria with shortest refractory period, during atrial fibrillation. Using this EAM tool, our study aimed to find the LA areas with the shortest refractory period to better recognize electrical targets for catheter ablation.

Methods

Retrospective analysis of an unicentric registry of individuals with symptomatic drug-refractory AF who underwent PVI with Carto® EAM. CLM was performed with a high-density mapping Pentaray® catheter before and after PVI and in 4 redo procedures. We assessed areas of short cycle length (SCL) (defined as 120 to 250ms), and their relationships with complex fractionated atrial electrograms (CFAE), and low-voltage zones (from 0.1 to 0.3mV).

Results

A total of 18 patients (8 men, median age 63 IQR 58–71 years) were included. Most patients presented with persistent AF (n=12, 67%), and 4 patients (22%) had a previous PVI. The mean shortest measured cycle length in AF was 140ms (SD ±27ms). All patients presented areas of SCL located in the PVs or their insertion, 70% in the posterior/roof region adjacent to the left superior pulmonary vein (LSPV) (figure 1) and 60% in the anterior region of the right superior pulmonary vein (RSPV). These two areas remained the fastest even after PVI. The anterior mitral region rarely presented SCL (17%). SCL were related to low-voltage areas in 94% and were adjacent to CFAE. Low-voltage areas and CFAE were more frequent and had a larger LA dispersion than SCL.

Conclusion

We confirmed in 3D mapping that PVs are the LA zones with shortest refractory period, not only in sinus rhythm but also during AF. The persistence of SCL areas in the border zones of the PVI lines suggest the benefit of a more extensive CLM guided ablation. Larger studies are needed.

Funding Acknowledgement

Type of funding sources: None. Short cycle length mapping
Is balloon cryoablation effective in common pulmonary trunk?
Authors: Graca Rodrigues T.E , Cunha N , Brito J , Silverio-Antonio P , Couto Pereira S , Silva B , Silva P , Barreiros C , Lima Da Silva G , Cortez-Dias N , Carpinteiro L , Pinto F.J , Sousa J
Published: October 2021

Introduction

Common pulmonary trunk (CPT) accounts for the most frequent pulmonary vein anatomical variation. The most frequent technique used for pulmonary vein isolation (PVI) is point-by-point radiofrequency, using cryoablation (CB) is still debatable. Some few studies have shown the feasibility and safety of CB in CPT atrial fibrillation (AF) patients (pts), most of them performed angio-CT prior to ablation.

Purpose

To analyzed AF pts with and without CPT submitted to CB in regarding of success rate and safety.

Methods

Single-center retrospective study of consecutive AF pts refractory to antiarrhythmics submitted to CB between 2017 and 2020. Before the procedure auriculography was performed in all pts to verify variations in pulmonary veins, however the procedure was not modify regarding the presence of CPT. Clinical records were analyzed to determine baseline characteristics, success rate and complications. Monitoring was performed with a 7-day event loop recorder at 3, 6 and 12 months and annually from the 2nd year. Success was defined by recurrence of AF (duration >30 seconds). Kaplan Meier survival curves were used to estimate the risk of events and the groups were compared using Chi-square and Mann-Whitney analysis.

Results

A total of 232 pts (60±12 years, 68% males) underwent CB. 29 pts had CPT (28 – common left pulmonary trunk and 2 – common right pulmonary trunk). Baseline characteristics were similar between groups, except for CHA2DS2VASc score and prior cerebrovascular disease history which were higher in CPT pts (3±2 vs 2±2, p=0.001; 24.1% vs 6.8%, p=0.007, respectively). The mean baseline CHA2DS2VASc was 2±2 and the median post-CB follow-up was 135 (IQ 32–249) days.

Both the 1 and 3 year arrhythmic recurrence after AF ablation was not significantly different when comparing CPT and non CPT group with a 3 year success rate of 95.8% in pts with CPV against 86.5% in pts without CPT (p=0.299).

There was no difference between groups (p=0.296; p=0,164, respectively) regarding the time of the procedure, radiation dose and rate of complications.

Conclusions

In our experience, balloon cryoablation for PVI is a safe and successful procedure in patients with CPT anatomical variation.

Funding Acknowledgement

Type of funding sources: None.
Real-world comparison of different periprocedural antithrombotic strategies for atrial fibrillation catheter ablation
Authors: Carvalho R , Rodrigues T , Rocha R , Ribeiro J , Silva G.L , Carpinteiro L , Cortez-Dias N , Sousa J
Published: October 2021

Introduction

Atrial Fibrillation (AF) catheter ablation carries high bleeding and thromboembolic risks, requiring a detailed assessment of overall risk-benefit profile regarding antithrombotic strategy. Vitamin K Anticoagulant (VKA) and Non-Vitamin K Antagonist Oral Anticoagulant (NOAC) have been used in the latest years in this setting, and with different interruption protocols periprocedural. Our goal was to evaluate the rate of acute adverse events (AAE) and compare them according to antithrombotic strategy used periprocedural, in a real-world basis.

Methods

A single-center retrospective study, including adult patients admitted to first AF catheter ablation, from 2004 to 2020. Different antithrombotic strategies (anticoagulation with VKA uninterrupted, anticoagulation with NOAC uninterrupted, no therapy or antiaggregation/interrupted ACO) were compared concerning the rate of any clinically relevant AAE; the composite of major AAE (hemopericardium and stroke/transient ischemic attack [TIA]) and minor AAE associated with vascular access. Descriptive statistics and logistic regression were used to compare groups according to the antithrombotic strategy with an alpha level of 0.05.

Results

Among the 868 patients included (mean age 59±12 yo, 67,5% [n=586] men), pulmonary vein isolation was performed under uninterrupted anticoagulation in 640 (73,7%), of which 595 patients with NOAC (68,5%) and 45 with VKA (5,2%). AF was paroxysmal, persistent and long-standing persistent in 63,4% (n=550), 21,4% (n=185) and 15,4% (n=133) patients, respectively. Mean CHADS-VASc score was 1,86±1,48. Over time there was a shift in the distribution of the type of antithrombotic therapy used, consistent with changes in recommendations (Graph 1).

The composite outcome occurred in 6,8% (n=62), including hemopericardium in 1,8% (n=16), stroke/TIA in 0,7% (n=6) and events related to vascular access in 1,4% (n=13) [Table 1]. No anticoagulation therapy or antiaggregation/interrupted ACO was more associated to the outcome, driven by major AAE, although the difference did not meet statistical significance (p=0,06) [Table 1]. No difference was found between VKA and NOAC group. Additionally, there was no diference in the incidence of hemorrhagic AAE since the implementation of an uninterrupted anticoagulation strategy periprocedural.

Conclusion

In our population of patients submitted to AF catheter ablation, an uninterrupted anticoagulation strategy is associated with lower rate of AAE, either with VKA or NOAC. Our real-world results are reassuring of the benefit of an uninterrupted strategy, and consistent with recent controlled trials.

Funding Acknowledgement

Type of funding sources: None. Antithrombotic therapies over timeClinically relevant acute adverse events
Do we need imaging support to minimize radiation exposure in cryo-ablation for atrial fibrillation? The VLADIMIR strategy
Authors: Guisasola Cienfuegos M , Lazaro Rivera C , Marco Del Castillo A , Otero Escudero M.M , Ramos Jimenez J , Borrego Bernabe L , Fontenla Cerezuela A , Lopez Gil M , Salguero Bodes R , Arribas-Ynsaurriaga F , Rodriguez Munoz D
Published: October 2021

Introduction and objective

Cryoballoon pulmonary vein isolation (CB-VPI) is non-inferior to radiofrequency ablation in patients with atrial fibrillation. Although protocols aiming to reduce radiation exposure have been developed, most of them use intracardiac echocardiography (ICE) or electroanatomic mapping (EAM) systems, which significantly increase procedure costs or may not be widely available. Previous studies aiming at fluoroscopy reduction have been published, achieving median fluoroscopy times around 10 minutes.

We developed a novel strategy to achieve Very Low rADIoscopic exposure to Minimize Ionizing Radiation during cryoablation of atrial fibrillation (VLADIMIR) (Table 1). The aim of this study was to assess its impact in acute procedural and clinical outcomes.

Methods

Consecutive patients undergoing CB-VPI were prospectively enrolled, treated with the VLADIMIR strategy and compared to a retrospective cohort of patients having undergone CB-VPI performed by the same operators with conventional fluoroscopy strategy. Primary end-points were fluoroscopy time and total dose area product (DAP). Secondary end-points were intraprocedural or early post-procedural complications.

Results

A total of 84 patients were enrolled. 50 patients underwent CB-VPI with conventional fluoroscopy strategy and in 34 patients the Vladimir strategy was applied. Vladimir group had significant lower median fluoroscopy time (2.98 min vs 20.65 min, p<0.001) and significant lower median DAP (4.15 Gy·cm2 vs 34.12 Gy·cm2, p<0.001) as compared with conventional fluoroscopy strategy group. Results from prespecified subgroup analysis between operators (senior vs fellow trainee) were consistent. No significant differences were found between both groups in periprocedural complications (Table 2).

Conclusion

The Vladimir protocol significantly reduces fluoroscopy time and radiation exposure during CB-VPI without affecting the rate of periprocedural complications.

Funding Acknowledgement

Type of funding sources: None. Table 1. The VLADIMIR strategyTable 2
Predictive performance of different bleeding risk scores in patients with atrial fibrillation and acute coronary syndrome or undergoing percutaneous coronary intervention
Authors: Lyu S , Zhu J , Yu L , Yang Y
Published: October 2021

Background

Standard scoring system for bleeding risk assessment has not been developed in patients with atrial fibrillation (AF) and acute coronary syndrome (ACS) or undergoing percutaneous coronary intervention (PCI). The study aims to evaluate the predictive value of the HAS-BLED, ORBIT, ARTIA, PARIS, and PRECISE-DEAPT score in patients with AF and ACS/PCI who received both anticoagulant and antiplatelet therapy.

Methods

A total of 930 patients with AF and ACS/PCI receiving both anticoagulant and antiplatelet therapy were consecutively recruited and followed up for 1 year. The primary endpoint was defined according to the bleeding academic research consortium (BARC) criteria as major (BARC 3a, 3b, 3c, and 5) and any bleeding (BARC 2, 3a, 3b, 3c, and 5). The secondary endpoints included major or minor bleeding according to TIMI criteria. Univariate and multivariate logistic regression were performed to evaluate the association between bleeding risk scores and outcomes. Receiver operating characteristic (ROC) curves were constructed and c-statistics were calculated to evaluate the predictive performance of different bleeding risk scores.

Results

BARC class ≥2 bleedings occurred in 36 patients (3.9%), while BARC class ≥3 bleedings were seen in 134 patients (14.4%). The HAS-BLED, ORBIT, ARTIA, PARIS, and PRECISE-DEAPT score were significantly associated with incidences of BARC class ≥2 and ≥3 bleedings during 1-year follow-up (all p<0.05). The ROC analysis showed that the predictive performance of the five bleeding risk scores for BARC class ≥3 bleedings were low-to-moderate [c-statistic: HASBLED 0.584 (0.552–0.616), ATRIA 0.624 (0.592–0.655), ORBIT 0.623 (0.591–0.654), PARIS 0.633 (0.601–0.664), PRECISEDAPT 0.616 (0.584–0.647)]. Multivariable logistic regression indicated that previous bleeding history and hemoglobin were independent predictors of BARC class ≥3 bleedings. Compared to the HAS-BLED score, the model constructed by previous bleeding history and hemoglobin displays a significant improvement in bleeding risk prediction (0.704 vs. 0.584, p=0.013).

Conclusions

In patients with AF and ACS/PCI receiving both anticoagulant and antiplatelet therapy, the HAS-BLED, ORBIT, ARTIA, PARIS, and PRECISE-DEAPT score displayed low-to-moderate performance for predicting BARC class ≥3 bleedings during 1-year follow-up. More accurate scoring systems for bleeding risk evaluation should be developed for these patients in the future.

Funding Acknowledgement

Type of funding sources: None. Receiver operating characteristic curve
Effectiveness and safety of non-vitamin K antagonist oral anticoagulants versus warfarin among nonvalvular atrial fibrillation patients with prior bleeding events
Authors: Lip G.Y.H , Keshishian A , Kang A , Luo X , Atreja N , Zhang Y , Schuler P , Jiang J , Lovett K , Yuce H , Deitelzweig S
Published: October 2021

Background

Patients with non-valvular atrial fibrillation (NVAF) use oral anticoagulants such as warfarin or non-vitamin K antagonist oral anticoagulants (NOACs) for the prevention of stroke. However, the effectiveness and safety of warfarin and NOACs can be influenced by pre-existing patient comorbidities, such as a history of bleeding, and limited evidence are available to inform the choice of the most appropriate anticoagulant treatment for NVAF patients with bleeding history.

Purpose

This study used five United States insurance claims databases to evaluate the risk of stroke/systemic embolism (S/SE) and major bleeding (MB) among NVAF patients with prior bleeding events who were prescribed NOACs versus warfarin.

Methods

This retrospective observational study used data from 5 databases (CMS Medicare and four commercial databases, covering >180 million beneficiaries) to select adult NVAF patients who were treated with apixaban, dabigatran, rivaroxaban, or warfarin (01JAN2013–30JUN2019). Patients were required to have a prior bleeding event, defined as a hospitalization with a diagnosis for intracranial hemorrhage (ICH), gastrointestinal (GI) bleeding or bleeding at other key sites prior to or during the index treatment episode. In each database, three 1:1 NOAC-warfarin propensity-score-matched (PSM) cohorts were created before pooling the results. Outcome measures were time to first stroke/SE, (ischemic stroke, hemorrhagic stroke, and SE), and time to first MB (gastrointestinal bleeding, intracranial hemorrhage, and MB at other key sites), and were measured from the index treatment episode to treatment discontinuation or switch, death, health plan disenrollment, or end of study period. Hazard ratios of S/SE and MB were calculated using Cox proportional hazards models.

Results

Among the eligible NVAF population, 8.2% of patients had a prior bleeding event (ICH: 12.3%; GI: 60.7%; Other: 27.0%). After PSM, a total of 43,092 apixaban-warfarin, 11,295 dabigatran-warfarin, and 32,723 rivaroxaban-warfarin patient pairs with prior bleeding were selected with a mean follow-up of 8–9 months. Apixaban and rivaroxaban were associated with a lower risk of S/SE, and dabigatran was associated with a similar risk of S/SE when compared to warfarin. Apixaban and dabigatran were associated with a lower risk of MB, and rivaroxaban was associated with a similar risk of MB, compared to warfarin (Figure).

Conclusion

Among NVAF patients with prior bleeding events, NOACs were associated with varying risks of S/SE and MB compared to warfarin. These results can help inform healthcare providers concerning the impact of OAC treatment in NVAF patients with history of bleeding.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Bristol-Myers Squibb Company and Pfizer, Inc.
The 30-day readmission of same-day discharge following pulmonary vein isolation for atrial fibrillation: a propensity score-matched analysis from National Readmission Database
Authors: Sahashi Y , Kuno T , Malik A.H , Briasoulis A
Published: October 2021

Introduction

The complication rate following pulmonary vein isolation (PVI) for atrial fibrillation (AF) has improved in recent decades with the increasing number of PVI worldwide. The effectiveness and safety of same-day discharge for PVI has not been elucidated well using a large nationwide database.

Purpose

The aim of our study was to evaluate the readmission rates within 30-days among patients receiving PVI for AF with the same-day discharge compared with the usual overnight observation protocol.

Methods

We performed a retrospective cohort study using the US Nationwide Readmission Database. Patients were divided into the two groups: the same-day discharge group and the overnight observation group (those who stayed at least one night following PVI). The primary outcome was an all-cause 30-day readmission rate following discharge in patients receiving PVI and a secondary outcome of total healthcare cost. A 1:3 propensity score matching was used to compare the safety within both protocols. Patients with peri-procedural complications such as pericardial, vascular, bleeding requiring transfusion, were excluded from the analysis.

Result

Among 30,776 patients (mean 67.2±11.4 years, 18,004 male (58.5%)) who received PVI from 2016 through 2018, 440 (1.42%) patients were discharged the same-day following PVI (same-day discharge group), and the remaining 30,336 patients stayed at least one night in the hospital (the overnight observation group). A propensity score analysis generated 1,751 matched pairs (440 in the same-day discharge group; 1311 in the observation overnight group). The 30-day readmission following discharge was not significantly higher in the same-day discharge group, compared to the overnight observation group (same-day discharge vs. overnight observation group: 12.7% vs. 9.7%, p=0.23; odds ratio [OR]:1.39, 95%confidence interval [CI]: 0.87–2.22) (Figure). Healthcare cost was significantly higher in the overnight observational group. ($25,237±14,036 vs. $30,749±16,383; p<0.01).

Conclusion

In this large nationwide study using a propensity score matching analysis, there was no significant difference in 30-day readmission rates following the same-day discharge in patients receiving PVI for AF compared with the overnight observation protocol.

Funding Acknowledgement

Type of funding sources: None.
Impact of atrial fibrillation in patients with colorectal cancer: a national inpatient sample database analysis
Authors: Patel N , Amgai B , Chakraborty S , Hajra A , Binit A , Patel Z , Ashish K , Reddy M , Aronow W , Khalid M
Published: October 2021

Background

Atrial fibrillation (AF) is the most common cardiac arrhythmia affecting approximately 1–2% overall population (1). Its causal relationship with colorectal cancer (CRC) is much for debate. According to one hypothesis, the presence of autoantibodies directed against ionic channels or acetylcholine receptors can predispose to the development of atrial fibrillation (2–3). Thus, AF may be regarded as an inflammatory complication in patients with colon cancer. Our study objective was to determine if AF impacts the outcome of patients with CRC.

Method

We analyzed the National Inpatient Sample (NIS) database from Oct-2015 to Dec 2018 using Stata 16.0. The NIS databases are released under the Healthcare Cost and Utilization Project, which includes inpatient admissions from the United States' participating hospitals. Total population with CRC were identified using their respective ICD-10 diagnostic codes then divided based on AF. To determine atrial fibrillation association with mortality and complications, we used multivariate logistic regression analysis using weights to generate nationally representative results. Later, a propensity-matched population analysis was done for the accuracy of the results.

Result

We found 245,305 patients admitted with CRC between Oct 2015 to Dec-2018 in the USA, out of which 28,170 (11.5%) were having AF. The mean age for the patients with AF was 77±10 compare to 65±14 years in those without AF. Patients with AF were associated with higher comorbidities and had a high population percentage with Carlson category three or above. There were 1,456 (5.2%) mortalities in the AF group compared to 5,689 (2.6%) in the other. The higher odds of mortality in patients with AF was present in multivariate logistic regression analysis in both non-propensity matched [1.71 (1.45–2.02), P-value: <0.000] and propensity-matched [1.44 (1.18–1.75), P-value: <0.001] cohorts. Patients with AF were hospitalized longer (9.20±7.8 vs. 6.85±7.0 days), leading to a high admission costs (US$ 25,875±22,875 vs. 20,087±19,314). Odds of complications such as need for blood transfusions [1.61 (1.05–1.29), P-value: 0.005], hemorrhage requiring blood transfusion [1.17 (1.05–1.29), P-value: 0.003], lower-GI bleed [1.31 (1.21–1.43), P-value: <0.001], sepsis [1.45 (1.30–1.62), P-value: <0.001], respiratory failure [1.39 (1.15–1.67), P-value: 0.001] etc. were also higher in group of patients with CRC and AF.

Conclusion

In our retrospective, propensity-matched national inpatient sample analyses of patients admitted with colorectal cancer, atrial fibrillation is associated with higher morbidity and mortality. AF was associated with a high burden of complications with prolonged hospital stay leading to increased health care expenditures.

Funding Acknowledgement

Type of funding sources: None.