bluuebunny/crossref_metadata_2025 huggingface dataset:
Temporal trends in incidence, patient characteristics, microbiology and in-hospital mortality in patients with infective endocarditis: a contemporary analysis of 86,469 cases between 2007 and 2019
Authors: Becher P M , Gossling A , Fluschnik N , Schrage B , Seiffert M , Schofer N , Blankenberg S , Kirchhof P M , Westermann D , Kalbacher D
Published: October 2022

Background

Infective endocarditis (IE) is characterized by high morbidity and mortality rates, despite recent improvements in diagnostics and treatment. We aimed to investigate incidence, clinical characteristics, and in-hospital mortality in a large-scale nationwide cohort.

Methods

Using data from the German Federal Bureau of Statistics, all IE cases in Germany between 2007 to 2019 were analyzed. Logistic regression models were fitted to assess associations between clinical factors and in-hospital mortality.

Results

In total, 86,469 patients were hospitalized with IE between 2007 and 2019. The mean age was 66.5±14.7 years and 31.8% (n=27,534/86,469) were female. Cardiovascular (CV) comorbidities were common. The incidence of IE in the German population increased from 6.3/100,000 to 10.2/100,000 between 2007 and 2019 (Figure 1). Staphylococcus (n=17,673/86,469; 20.4%) and streptococcus (n=17,618/86,469; 20.4%) were the most common IE-causing bacteria. The prevalence of staphylococcus gradually increased over time, whereas blood culture-negative IE (BCNIE) cases decreased (Figure 2). In-hospital mortality in patients with IE was 14.9%. Compared to BCNIE, staphylococcus and gram-negative pathogens were associated with higher in-hospital mortality. In multivariable analysis, factors associated with higher likelihood of in-hospital mortality were advanced age, female sex, CV comorbidities (e.g., heart failure, COPD, diabetes, stroke), need for dialysis or invasive ventilation, and sepsis.

Conclusions

In this contemporary cohort, incidence of IE increased over time and in-hospital mortality remained high (∼15%). While staphylococcus and streptococcus were the predominant microorganisms, bacteremia with staphylococcusand gram-negative pathogens were associated with higher likelihood of in-hospital mortality. Our results highlight the need for new preventive strategies and interventions in patients with IE.

Funding Acknowledgement

Type of funding sources: None.
Long-term clinical course and prognostic factors of heart failure with reduced ejection fraction (HFrEF) patients underwent primary prophylactic implantable cardioverter defibrillator (ICD)
Authors: Sugawara M , Kondo Y , Yoshino Y , Ryuzaki S , Chiba T , Kitagawa M , Ito R , Nakano M I , Kajiyama T , Nakano M A , Kobayashi Y
Published: October 2022

Background

For decades, ICD is a well-established therapy for improving prognosis of structural heart disease with severe cardiac dysfunction, and ICD for primary prophylaxis against sudden cardiac death were routinely provided. However, long-term prognosis and clinical course are different in each individual patient with an ICD, and it is moreover unclear what kind of factors might have influences on their clinical outcomes.

Purpose

The aim of this study is to clarify long-term prognosis and predictors of future major adverse cardiac events (MACEs) in HFrEF patients with an ICD as primary prophylaxis in Japanese population.

Methods

We retrospectively analyzed our ICD database. Patients underwent primary prophylactic ICD implantation from 2006 to 2020 at our institute and met the criteria of ICD recommendation of the latest Japanese guideline. Its requirements are receiving optimal medication therapy, symptomatic heart failure (New York Heart Association classification II or greater), and severe cardiac dysfunction (left ventricular ejection fraction (LVEF) is 35% or less). Additionally, prior NSVT is considered Class I ICD recommendation. In the case of ischemic cardiomyopathy (ICM), ICD implantation was done at least 40 days after myocardial infarction and at least 90 days after revascularization. MACEs were defined as composite outcome of cardiovascular death, heart failure hospitalization, and appropriate ICD therapies.

Results

A total of 148 consecutive patients were enrolled (male, 120 (81%); age, 62.1±11.8 years; LVEF, 23.0±5.86%; left ventricular end-diastolic diameter (LVDd), 67.6±9.26mm; paroxysmal or persistent atrial fibrillation (AF), 38 (26%); NSVT, 113 (76%); use of class III antiarrhythmic drugs, 48 (32%); ICM, 49 (33%); cardiac resynchronization therapy (CRT), 63 (43%)). One hundred twenty patients (81%) were programmed with a shock-only zone over 200 beats per minute. The median follow-up duration was 58.5 months. Among those 148 patients, MACEs were occurred to 60 patients (41%). As a result of dividing all patients into two groups by the occurrence of MACE, LVEF and LVDd were worse in MACE(+) group, whereas, MACE(−) had greater number of co morbidities. The results of cox-regression analysis showed LVDd (HR: 1.07, 95% CI: 1.03–1.12, p<0.001), AF (HR: 2.88, 95% CI: 1.56–5.31, p<0.001) and ICM (HR: 1.78, 95% CI: 1.00–3.16, p=0.049) were the independent predictors of MACEs (Table). However, initial ICD programming was not related to the occurrence of MACE.

Conclusions

The incidence of MACEs in patients with an ICD and severe HFrEF was substantially high in this Japanese population. Etiology of ICM, left ventricle size, and AF were the potential risk factors for future MACEs.

Funding Acknowledgement

Type of funding sources: None.
Other rhythm abnormalities found in 10,593 patients with paroxysmal atrial fibrillation over a 14-day ambulatory ECG monitoring period
Authors: Bardy G , Wang M , Boleyn R , McLendon K
Published: October 2022

Background

The incidence of other arrhythmias in patients with Paroxysmal Atrial Fibrillation (PAF) can affect choice of subsequent diagnostic procedures as well as drug, implanted device and ablation management. In the endless stream of new ECG monitoring technologies, whose primary focus sits on AF identification, other arrhythmias can be minimized in their importance. And yet, in patients with PAF, management is often altered by the presence of both significant and even subtle additional concomitant rhythm abnormalities. Clinically meaningful non-PAF rhythms may not be reliably captured by most cardiac ambulatory ECG monitors, especially those focusing purely on AF.

Purpose

The objective of this study was to identify the extent and types of other unique rhythm abnormalities that might influence management in patients found to have PAF on a routine outpatient ambulatory ECG.

Methods

A total of 10,593 pts wearing an ambulatory ECG monitor had PAF. Monitors were ordered for standard clinical indications predominantly by their managing cardiologists. Patient ECG data was interpreted by 3 serial readers clinically informed on electrophysiological principles of arrhythmia diagnostics. Concomitant rhythm disorders, as manifested on the surface ECG monitor, were then quantified as a percentage of the PAF study population. Patients with chronic AF were excluded from this analysis.

Results

The primary results are summarized in Figure 1. Of 10,593 pts with PAF, only 391 (4%) were found to have only PAF and no other rhythm abnormalities. At least 1 additional rhythm abnormality was found in 96% and 2-to-8 additional rhythm disorders were present in 68% of patients.

Conclusion

Nearly all patients with PAF have additional rhythm abnormalities that can only be identified using a cardiac monitor with high P-wave fidelity. Even modest, and certainly serious, additional ECG rhythm abnormalities can alter physician management of PAF as pertains to selection of additional diagnostic testing, drug choice, device selection, and/or ablation specifics. Simplistic and/or commercial grade ECG monitors cannot provide such detail and carry the risk of misdirecting patient management.

Funding Acknowledgement

Type of funding sources: None.
Various arrhythmia types and their day-by-day occurrence rates over a 14-day period using a P-wave sensitive ambulatory ECG monitored population
Authors: Bardy G , Wang M , Boleyn R , McLendon K
Published: October 2022

Background

Many studies on ECG monitoring and arrhythmia detection use the term “diagnostic yield”, a vague term and one without the type of diagnostic precision that cardiologists value. Moreover, diagnostic yield of specific arrhythmias is not well understood on a day-by-day basis.

Purpose

We used a continuous 14-day ECG monitor to record the incremental occurrence of a broad variety of specific arrhythmias each day from a general outpatient population suspected of having an arrhythmia.

Methods

A total of 546 patients were monitored for 14±1 day in the absence of artifact that would otherwise obscure the rhythm. Without such stipulations, arrhythmias could not be truly categorized as a function of time. Patients were randomly selected who satisfied the aforementioned criteria. The studies were prescribed by the patient's managing physician for standard clinical indications, and they spanned across 237 distinct institutions. The recordings were interpreted by 3 serial readers clinically knowledgeable on electrophysiological principles of arrhythmia diagnostics. All reports were then confirmed in their entirety by a cardiac electrophysiologist. The daily diagnostic rate for specific arrhythmia occurrence was then tabulated. Of note, algorithmic and AI diagnostic approaches were not relied upon for arrhythmia diagnoses.

Results

Select arrhythmia/conduction abnormalities are shown in the attached Figure, demonstrating different arrhythmias manifesting at different rates. In 61% of pts, at least one rhythm disorder was found that could affect patient management over 14 days. In 28% of pts, two disorders were found while 12% had three or more disorders. P-wave specificity on the ECG aided in identifying 67.9% of those unique arrhythmias. When more than one arrhythmia type was identified, they typically occurred on different days. In contrast, the standard 1-day report, if implemented, would have diagnosed only 20% of patients and rarely would have found multiple rhythm abnormalities

Conclusion

Different arrhythmia categories manifest at different rates on a 14-day continuous ECG. Clinical abnormalities in rhythm and/or conduction occur in 61% of patients randomly selected from a broad array of institutions. Moreover, 28% had 2 disorders and 12% had >3 disorders, usually occurring on different days. Lastly, 67.9% of rhythms were identified due to a high fidelity P-wave ECG signal. These findings suggest that a 14-day P-wave sensitive ECG recording has substantive diagnostic value even if a suspected arrhythmia were to occur on day 1. Further, ECG recordings of 1 day (i.e., standard Holter monitor duration) severely diminish diagnostic value and should be avoided.

Funding Acknowledgement

Type of funding sources: None.
Transformation of computerized electrocardiogram data into novel means to differentiate wide complex tachycardias
Authors: Katbamna B , Kashou A H , Shaikh P , Lococo S , Cooper D , Cuculich P , Asirvatham S , Noseworthy P , Desimone C , May A
Published: October 2022

Background

Accurate automated wide QRS complex tachycardia (WCT) discrimination between ventricular tachycardia (VT) and supraventricular wide complex tachycardia (SWCT) can be accomplished using novel calculations derived from computerized electrocardiogram (ECG) data from paired WCT and baseline ECGs.

Purpose

Our aim was to develop and trial novel WCT discrimination approaches for WCT patients with and without a corresponding baseline ECG. Central to this analysis was the creation and use of a novel parameter (i.e., percent monophasic time-voltage area [PMonoTVA] [%]) that may be derived from computerized ECG measurements present on the WCT ECG alone.

Methods

In a two-part study, we derived and tested WCT differentiation models comprised of novel and previously established parameters formulated from computerized data of paired WCT and baseline ECGs. In Part 1, novel and established parameters generated from WCT and baseline ECG data were used to derive, validate, and compare five different binary classification models: (i) logistic regression [LR], (ii) artificial neural network [ANN], (iii) Random Forests [RF], (iv) support vector machine [SVM], and (v) ensemble learning (EL). In Part 2, two unique LR models were derived, validated, and compared using parameters generated from computerized data of the (i) WCT ECG alone (i.e., Solo Model) and (ii) paired WCT and baseline ECGs (i.e., Paired Model).

Results

In Part 1, among 103 patients with VT or SWCT diagnoses established from corroborating electrophysiology studies or intra-cardiac device recordings, favorable diagnostic performance was achieved by all modeling technique subtypes: LR (area under the receiver operating characteristic curve [AUC] 0.95), ANN (AUC 0.91), RF (AUC 0.97), SVM (AUC 0.98), and EL (AUC 0.97). In Part 2, among 235 patients with a VT or SWCT diagnosis established with (Gold Standard cohort) or without (Non-Gold Standard cohort) a corroborating electrophysiology procedure or intra-cardiac device recording, favorable diagnostic performance was achieved by the Solo Model (AUC 0.86) and Paired Model (AUC 0.95) (Table).

Conclusion

Accurate WCT discrimination may be accomplished using novel parameters derived from computerized data of the WCT ECG alone and paired WCT and baseline ECGs.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Institute of Health
Morphology-Voltage-P-wave duration (MVP) score in prediction of incident atrial fibrillation in an elderly epidemiologic cohort
Authors: Baturova M A , Cornefjord G , Carlson J C , Johnson L S B , Smith J G , Platonov P
Published: October 2022

Background

Interatrial block (IAB) on electrocardiography (ECG) and reduced P wave voltage reflect atrial abnormalities which may contribute to development of atrial fibrillation (AF).

Purpose

We aimed to assess the value of a recently proposed ECG risk score that combines the morphology, voltage and length of the P wave (MVP score) for prediction of incident AF in a prospective population-based setting.

Material and methods

The study population is based on the large, prospective Malmö Preventative Project (MPP) cohort. We included subjects without a history of AF, with a readable ECG in sinus rhythm and an echocardiography performed in 2002–2006 (n=983, mean age 70±5 years, 38% females). Median follow-up was 4.2 (IQR 3.7–4.8) years. ECGs were digitally processed using the Glasgow algorithm. Advanced IAB (aIAB) was defined as a P-wave ≥120 ms and biphasic morphology (+/−) in inferior leads, partial IAB (pIAB) as P-wave ≥120 ms and a monophasic positive morphoology in inferior leads. MVP score was calculated based on the P-wave morphology in inferior leads, voltage in lead 1, and P-wave duration (Table 1).Incident AF events (n=66, 7%) were obtained from the Swedish Hospital Discharge Register and Cause of Death Register. Cox regression analysis and Kaplan Meier curve analysis were used to study the association of echocardiographic and P-wave characteristics with the risk of new onset AF.

Results

At baseline the mean MVP score was 1±1, none of the subjects had MVP score above 4. MVP score correlated with left atrial (LA) area: Pearson r=0.192, p<0.001. After adjustment for age, gender and LA enlargement expressed as LA area >20 cm2, new onset AF was associated with MVP score 4 (HR 6.17, 95% CI 1.76–21.64 compared to those with MVP score <4, Figure 1). Neither aIAB (univariate HR 1.93 CI 95% 0.82–4.56), nor pIAB (univariate HR 1.16 CI 95% 0.52–2.55) predicted incident AF.

Conclusion

In a population-based elderly epidemiological cohort, the ECG-based MVP score was significantly associated with incident AF, independently of LA enlargement.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): The Swedish Heart-Lung Foundation
Cardiac dysrhythmias among coronavirus-19 recovered symptomatic patients
Authors: Shamia D , Tsaban G , Baham L , Raviv Y , Haim M
Published: October 2022

Background

The coronavirus (COVID-19) pandemic, which affected millions of people worldwide, is associated with a chronic fatigue sequela, also known as long-COVID. While various adverse effects of COVID-19 on the cardiovascular system were reported, the prolonged sequela of COVID-19 on heart rhythm remains unknown.

Aim

To describe the prevalence of cardiac dysrhythmias among patients who presented with Long Covid following recovery from COVID-19 infection.

Methods

We conducted a prospective study among 87 patients who suffered from Long Covid syndrome following recovery from COVID-19 and were treated in the COVID-19 recovery clinic between December 2020 and June 2021. All patients were referred for transthoracic echocardiography (TTE) and 24-hour Holter examination.

Results

The mean age was 52+13 years, and 52 (59.8%) patients were females. Seventy-nine (90.8%) of the patients had normal sinus rhythm without evidence of any arrhythmias. Atrial premature beats were recorded in 70 (80.5%) patients with a median of 6/day (interquartile range 3–20/day; maximum: 5180/day). Ventricular premature beats were recorded in 50 (57.5%) patients with a median of 4/day (interquartile range 2–19/day; maximum: 6847/day). Overall, seven patients (8%) had sustained atrial dysrhythmias: one had atrial fibrillation, one had atrial flutter, and five had atrial tachycardia. Sixty-six (75.9%) patients underwent TTE, which was mainly unremarkable as 65 patients had a normal left ventricular function, and three (4.5%) patients had evidence of pulmonary hypertension.

Discussion

Cardiac arrhythmias are not uncommon among symptomatic COVID-19 recovered patients. Atrial arrhythmias were most common, with an up to 8% incidence rate. These findings may suggest that atrial dysrhythmias may be associated with long-term symptomatic sequela of COVID-19 infection.

Funding Acknowledgement

Type of funding sources: None.
Validation of coala heart monitor
Authors: Paul Nordin A , Mohammad Ali A , Carnlof C , Drca N
Published: October 2022

Background/Introduction

Atrial fibrillation (AF) can be asymptomatic and it is associated with stroke and heart failure which can present as first symptoms [1,2]. There is increasing evidence of benefits of screening for AF to prevent ischemic stroke by initiating anticoagulation therapy in affected individuals [3]. There are several devices used for screening of AF [4] and one of them is Coala Heart Monitor (CHM), which is a handheld device, connected by blue-tooth to a smartphone for registration of the rhythm from the chest and the thumbs. The aim with this this study was to validate the accuracy of CHM for detecting atrial tachyarrhythmia (ATA) (AF, atrial flutter or atrial tachycardia) compared to 12-lead-ECG.

Methods

Eligible participants were ≥18 years of age, planned for a 12-lead-ECG, with a history of ATA. Exclusion criteria were; pacemaker or implantable cardioverter-defibrillator (ICD)-treatment, ongoing arrhythmia that was not ATA or if the patient was unwilling or unable to provide informed consent. One hundred and eleven 12-lead-ECG were collected and immediately after a 30 + 30 second thumb-and chest-registration from CHM where collected. 12-lead-ECG independently interpreted by two electrophysiologist was used as the reference standard (100% coherence). In one patient neither chest nor thumb-registration could be interpreted due to bad quality, and this was not included in the analysis. Eight thumb-registrations and three chest-registrations could not be interpreted and in these cases the other registration could be interpreted. In one case there was disagreement between interpreter one and two, and in this case a third interpreter was involved.

Results

Mean age was 65.2±12.1 years and 28.8% were female. Prevalence of ATA was 36.4%. The sensitivity for ATA was 100% (95% CI, 96.3% - 100%) and the specificity was 100% (95% CI, 96.3% - 100%).

Conclusion

CHM provides excellent sensitivity and specificity for ATA compared to 12-lead-ECG.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Swedish Research Council
The use of novel 3D dark-blood late gadolinium enhancement MRI to determine the optimal threshold for atrial scar after pulmonary vein isolation ablation
Authors: Bijvoet G P , Hermans B J M , Holtackers R J , Luermans J G L M , Linz D , Maesen B , Mihl C , Nijveldt R , Vernooy K , Wildberger J E , Schotten U , Chaldoupi S M
Published: October 2022

Background

Dark-blood late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) is proved to be superior to bright-blood LGE MRI in localising subtle subendocardial scar in the ventricles, because of improved contrast between myocardial scar and blood. However, dark-blood LGE MRI has not yet been applied to identify atrial scar in the left atrium (LA) and therefore its threshold to determine scar is unknown.

Purpose

To determine the optimal intensity threshold for 3D dark-blood LGE MRI for atrial ablation scar after pulmonary vein isolation (PVI)

Methods

Twelve re-do PVI patients with symptomatic atrial fibrillation (AF) who underwent pre-procedural 3D dark-blood LGE MRI were included. The image intensity ratio (IIR = myocardial intensity normalized to the blood pool) from the LGE MRI were calculated using ADAS-AF. High-density bipolar voltages (BiV) maps were recorded during sinus rhythm prior to ablation. All BiV locations ≤5 mm from the ADAS LA anatomy were compared with the corresponding IIR, using custom-made software in MATLAB. To achieve an equal ratio between scar (BiV ≤0.15 mV) and non-scar (BiV >0.15 mV) for each patient, non-scar pairs were randomly resampled to the same number as scar pairs. This was repeated 10 times and for every random selection, receiver operating characteristics (ROC) analysis was performed to determine the optimal IIR threshold (provided by the Youden's index) for scar defined as BiV <0.15 mV (Figure 1). All IIR thresholds and areas under the curve were averaged to determine the overall performance and optimal IIR threshold.

Results

Of the 12 included patients, 8 had prior cryo PVI, 2 radiofrequency PVI, and 2 surgical/hybrid AF ablation. ROC curve analysis estimated the average optimal threshold for predicting BiV <0.15 mV to be an IIR of 1.106, with a mean area under the curve (AUC) of 0.73 (Figure 1). Figure 2 shows two examples of the IIR map (A), BiV map (B), and the correspondence map (C) providing information on spatial agreement between IIR and BiV. This individual qualitative assessment provides insight into the spatial variation between techniques and may facilitate future studies on the pathophysiological understanding of atrial ablation scarring.

Conclusion

This is the first study to use the novel 3D dark-blood whole heart LGE MRI to evaluate LA ablation scar after PVI. Based on the ROC analyses, an IIR of 1.106 is the optimal threshold for atrial ablation scar, defined as high density bipolar voltage <0.15 mV.

Funding Acknowledgement

Type of funding sources: None.
Artificial intelligence to reduce artifact in cardiac electrophysiological signals
Authors: Ruiperez-Campillo S , Deb B , Feng R , Ganesan P , Tjong F V Y , Clopton P , Rogers A J , Narayan S M
Published: October 2022

Background/Introduction

Signals in Electrophysiology cases are often noisy despite laboratory shielding and filtering, and current noise-reduction methods are suboptimal. Template matching can identify a “nearest type” of electrogram, but libraries of signal shapes may be unavailable. Beat averaging can reduce noise but obscures beat-to-beat variations and is not optimal to analyze dynamically changing signals, such as when moving a catheter in the heart. Smoothing reduces noise yet blurs high frequency components.

Purpose

We set out to test if machine learned autoencoders could reduce noise in single beats without requiring massive training data or beat libraries. Specifically, we hypothesised that noisy electrograms in small datasets of atrial signals could be de-noised using an encoder-decoder neural network (NN) using transfer learning of machines trained to recognize key features in larger datasets of related signals.

Methods

We applied NN to monophasic action potentials (MAPs), because they have visually verifiable shapes. The NN was first trained to reconstruct 5706 left and right ventricular MAPs in 42 patients (67±13y; Fig. 1A). Transfer learning was then used to apply the NN to a much smaller dataset of 641 atrial MAPs in 21 patients (67±5y, 13 women; Fig. 1B, D, F).

Results

NN reconstructed atrial MAPs with a Pearson correlation of 0.87±0.11. After fine-tuning, NN reconstruction accuracy improved dramatically (Pearson 0.99±0.01; p<0.001). In Fig. 1B–G the NN learned key MAP features (upstroke, triangular descent, terminus) and thus could eliminate ventricular artifact and electrical circuit noise without specific training or manual annotation.

Conclusion

Machine learned autoencoders are a novel and powerful approach to de-noise electrophysiological signals in a dynamic, beat-to-beat fashion. The ability to learn fundamental signal features from models trained in large datasets, and apply them via transfer learning to small datasets in different heart chambers may have wide ranging applications for automated signal annotation, mapping and ablation.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): NIH
Left atrial functions in the early period after cryoballoon ablation for paroxysmal atrial fibrillation
Authors: Soysal A , Gulfidan A , Akman Z , Koroglu A E , Tokdil H , Raimoglu U , Yalman H , Aksu T , Atici A , Golcuk E , Ikitimur B , Yalin K
Published: October 2022

Introduction

In patients with paroxysmal atrial fibrillation (PAF), functional changes are observed in the left atrium (LA) after pulmonary vein isolation (PVI) with catheter ablation. Although previous studies have investigated the altered mechanical functions of LA with radiofrequency (RF) ablation, changes in LA functions in the early period after cryoablation have not been clearly demonstrated.

Methods

Thirty three patients (mean age: 57±11; 54.5% men) with PAF underwent cryoablation procedure with second generation cryoballoon (CB-2). All patients were in sinus rhythm before and after the procedure. LA dimensions, LA strain parameters (LAsr-LAscd-LAsct) and left ventricular diastolic function parameters were evaluated by Doppler echocardiography before and 3 months after the procedure.

Results

Acute procedural success was achieved in all cases. No major complications were occurred. A significant recovery in LA reservoir strain (p=0.009) was observed. No significant change was demonstrated in remaining echocardiographic parameters.

Conclusion

LA reservoir strain is an indicator of left atrial compliance and significant improvement in mechanical functions may occur even in the early period after cryoballoon ablation in patients with PAF in contrast to LA function deterioration observed in RF ablation.

Funding Acknowledgement

Type of funding sources: None.
Zero-fluoro AVNRT ablation
Authors: Soether C M , Boehmer A A , Dobre B C , Kaess B M , Ehrlich J R
Published: October 2022

Background

Atrioventricular-nodal reentry tachycardia (AVNRT) is a common supraventricular tachycardia, particularly in younger patients. First-line therapy in symptomatic patients is radiofrequency catheter ablation (RFCA). Catheter placement and ablation are typically performed by fluoroscopy guidance implying a non-negligible exposure of ionizing radiation for patient and laboratory personnel.

Purpose

We aimed to demonstrate feasibility and safety of AVNRT ablation using 3D-electroanatomic mapping (3D-EAM) as sole and additional means of catheter guidance compared to conventional fluoroscopic positioning. Endpoints were: procedure duration, fluoroscopy duration, radiation dose and occurrence of any complication.

Methods

We retrospectively included consecutive patients (n=68, mean age 55±18 years) who underwent RFCA of AVNRT between 01/2020 and 12/2021 in our hospital. One group was a priori allocated to conventional fluoroscopy mapping (convFluoro, n=30), the other procedures were performed under 3D-EAM using Ensite NavX (NavX). From the latter, slow-pathway RFCA could be performed without any fluoroscopy (zeroFluoro) in 20 patients, in 18 cases additionally fluoroscopy was used due to difficult anatomic conditions (NavX+Fluoro). Success of RFCA was defined as slow-pathway elimination.

Results

There was no significant difference in procedure duration between the convFluoro and overall NavX group (74±24 min vs. 87±29 min, P=NS). However, NavX+Fluoro group (comprising more complicated cases) had longer procedure duration compared to convFluoro group (94±30 min vs. 74±24 min, p<0.05). The use of 3D-EAM significantly reduced fluoroscopy duration comparing convFluoro with NavX+Fluoro (12±9 min vs. 7±6 min, p<0.05) and convFluoro with overall NavX-group (12±9 min vs. 3±5 min, p<0.0001). Likewise, radiation dose was significantly decreased by means of 3D-EAM (NavX: 60±113 cG cm2 vs. convFluoro: 169±166 cG cm2, p<0.01). 3D-EAM guided RFCA was successful in all patients (100%), success rate in convFluoro-group was 87% (P=NS). Minor complications occurred in two cases (7%) in the convFluoro-group and 4 cases (11%) in the NavX-group (P=NS). No severe complication, such as pericardial effusion or permanent AV-block occurred in any group.

Conclusion

Zero-fluoroscopy 3D-EAM-guided RFCA in patients with AVNRT is feasible and safe. Without prolonging procedure duration, 3D-EAM can reduce fluoroscopy duration leading to lower radiation exposure and making electrophysiological study safer for laboratory staff and patients.

Funding Acknowledgement

Type of funding sources: None.
Arrhythmia in pregnant women: what management is better?
Authors: Abdrakhmanov A , Ainabekova B , Nuralinov O , Bakytzhanuly A , Smagulova A
Published: October 2022

Background

Arrhythmias in pregnant women are commonly seen but have not been extensively studied. Drug therapy or catheter ablation during pregnancy may be required in cases of maternal arrhythmias. However, the studies did not examine the outcomes of pregnancy in cases with different management of arrhythmias.

Objective

We aimed to determine if there are any differences in pregnancy outcomes in women with disparate types of arrhythmia treatment.

Methods

We conducted a prospective study of all pregnant patients who were admitted to our hospital with arrhythmias from 2017–2020. For patients with benign arrhythmias drug therapy was not required (n=11; 14.5%, 1st group). Antiarrhythmic treatment was justified in cases with frequent symptoms and haemodynamic instability (n=65; 85.5%). Patients with effective antiarrhythmic therapy were included in 2nd group (n=31; 40.8%). In patients with drug refractory and dangerous rhythm disturbances (n=34; 44.7%, 3d group) were performed zero-fluoroscopy catheter ablation.

Results

A total of 76 pregnant women were admitted with arrhythmias. Mean age was 27.24±5.15 years, mean gestation age 21.27±5.34 weeks. Supraventricular tachycardia was the most common arrhythmias (n=41; 53.9%) This was followed by premature contractions (n=27; 35.6%) and ventricular tachycardia (n=8; 10.5%). There was significant difference in frequency of performed catheter ablation for disparate types of arrhythmia: 70.7% for cases of supraventricular tachycardia, 25% - ventricular tachycardia and 11.1% - premature contractions (p=0.000). Ablations were effective in all cases without adverse outcome. All ablations were performed without fluoroscopy. Vaginal delivery was in the majority in all groups (75.6% vs 62.5% vs 74.1%, p=0.736). Similarly, no differences were noted in obstetric complication (14.6% vs 12.5% vs 18.5%, p=0.656). None of them had fetal mortality.

Conclusions

Some patients with arrhythmias needed catheter ablation during pregnancy. There was no significant difference in type of delivery and neonatal outcomes in women with separate management of arrhythmias.

Funding Acknowledgement

Type of funding sources: None.
Transseptal puncture for left atrial ablation: risk factors for cardiac tamponade and a proposed causative classification system
Authors: Roelas M , Vyas R , Maclean E , Mahtani K , Butcher C , Ahluwalia N , Honarbakhsh S , Finlay M , Chow A , Earley M J , Sporton S , Lambiase P D , Schilling R J , Hunter R J , Segal O R
Published: October 2022

Background

Cardiac tamponade is a high morbidity complication of transseptal puncture (TSP).

Purpose

We examined the associations of TSP-related cardiac tamponade (TRCT) for all patients undergoing left atrial ablation at our centre from 2016–2020.

Methods

Patient and procedural variables were extracted retrospectively. Cases of cardiac tamponade were scrutinised to adjudicate TSP culpability. Adjusted multivariate analysis examined predictors of TRCT.

Results

3,239 consecutive TSPs were performed; cardiac tamponade occurred in 51 patients (incidence: 1.6%) and was adjudicated as TSP-related in 35 (incidence: 1.1%; 68.6% of all tamponades). Patients of above-median age (OR 2.4 (1.19–4.2), p=0.006) and those undergoing re-do procedures (OR 1.95 (1.29–3.43, p=0.042) were at higher risk of TRCT. Of the operator-dependent variables, choice of transseptal needle (Endrys vs Brockenbrough, p>0.1) or puncture sheath (Swartz vs Mullins vs Agilis vs Vizigo vs Cryosheath, all p>0.1) did not predict TRCT. Adjusting for operator, equipment and demographics, failure to cross the septum first pass increased TRCT risk (OR 4.42 (2.45–8.2), p=0.001), whilst top quartile operator experience (OR 0.4 (0.17–0.85, p=0.002), transoesophageal echocardiogram (TOE prevalence: 26%, OR 0.51 (0.11–0.94), p=0.023), and use of the SafeSept guidewire (OR 0.22 (0.08–0.62), p=0.001) reduced TRCT risk. An increase in SafeSept wire use over time (2016: 15.6%, 2020: 60.2%) correlated with an annual reduction in TRCT (R2=0.72, p<0.001) and was associated with a relative risk reduction of 70%.

Conclusions

During left atrial ablation, the independent predictors of TRCT were patient age, re-do procedure, operator experience, unsuccessful first pass, TOE-guidance, and use of the SafeSept wire. A novel classification system for the causes of cardiac tamponade is proposed (table 1); this may be of interest to clinical trialists or auditors evaluating patient safety.

Funding Acknowledgement

Type of funding sources: None.
Cryoballoon ablation of left atrial roof with a novel cryoballoon system
Authors: Shigeta T , Yamauchi Y , Oda A , Sudo K , Arai H , Sagawa Y , Okishige K , Goya M , Sasano T
Published: October 2022

Introduction

A novel cryoballoon system (POLARx) has emerged and its efficacy regarding pulmonary vein isolation (PVI) has been already investigated. On the other hand, cryoballoon ablation of left atrial (LA) roof has been performed using a conventional cryoballoon system (Arctic Front Advance Pro [AFA-Pro]) in addition to PVI. However, cryoballoon ablation of LA roof with POLARx has not been investigated yet.

Methods

We performed cryoballoon ablation of LA roof with POLARx in 22 patients after we achieved PVI. After the cryoballoon ablation, complete conduction block at LA roof and isolation of all PVs were confirmed by creating an activation map during high right atrium pacing. If they could not be obtained with solely a cryoballoon, touch up ablation with radiofrequency ablation was permitted. The procedural data during ablation with POLARx was compared with those during ablation with AFA-Pro we had performed in a historical cohort of patients (n=46).

Results

Complete conduction block at LA roof without touch up ablation could be obtained in all the patients in POLARx group and 44 (95.7%) patients in AFA-Pro group. Total procedure time was almost similar in both groups (164.2±35.4 min for POLARx vs 180.3±35.4 min for AFA-Pro, p=0.10). During LA roof line ablation, nadir balloon temperature was significantly lower in POLARx group (right side: −53.6±4.4°C for POLARx vs −45.6±4.6°C for AFA-Pro, p<0.01, central part: −56.4±4.3°C for POLARx vs −46.0±3.7°C for AFA-Pro, p<0.01, left side: −55.1±3.5°C for POLARx vs −45.7±5.3°C for AFA-Pro, p<0.01), and balloon temperature reached −40°C earlier in POLARx (right side: 30.7±8.9 sec for POLARx vs 78.0±39.8 sec for AFA-Pro, p<0.01, central part: 30.6±9.3 sec for POLARx vs 65.9±33.3 sec for AFA-Pro, p<0.01, left side: 30.4±4.2 sec for POLARx vs 78.8±49.6 sec for AFA-Pro, p<0.01). Total freezing time required for LA roof line ablation was significantly shorter in POLARx group (589.3±163.6 sec for POLARx vs 877.5±191.7 sec for AFA-Pro, p<0.01).The scar area created after LA roof line ablation was similar in both groups (9.3±4.1 cm2 for POLARx vs 11.0±4.8 cm2 for AFA-Pro, p=0.23).

Conclusion

Complete conduction block at LA roof could be obtained after cryoballoon ablation with POLARx, in the same way as AFA-Pro. Lower nadir balloon temperature could be expected in shorter freezing time during LA roof line ablation in using POLARx compared with AFA-Pro.

Funding Acknowledgement

Type of funding sources: None.
How to perform effective cryoballooon ablation of left atrial roof: considerations after experiences of more than 1000 cases
Authors: Shigeta T , Yamauchi Y , Oda A , Sudo K , Arai H , Sagawa Y , Okishige K , Goya M , Sasano T
Published: October 2022

Introduction

Although pulmonary vein isolation is the cornerstone of atrial fibrillation (AF) ablation, concomitant cryoballoon ablation of left atrial (LA) roof has been expected to improve clinical outcomes after ablation. We demonstrate characteristics and efficacy of cryoballoon ablation of LA roof through our experiences from a large volume of procedures.

Methods

We had performed cryoballoon ablation of LA roof in 1036 procedures including 202 redo procedures in AF patients since June 2016. Among these procedures, we analyzed 834 patients (309 paroxysmal AF) who had undergone de novo ablation for AF. We confirmed whether the complete conduction block of LA roof line was obtained after the ablation.

Results

LA roof line block was obtained in 767 patients (92.0%) without touch up ablation with a radiofrequency catheter (Group A). LA diameter (LAD) was significantly smaller (43.6±6.6mm vs 47.4±7.5mm, p<0.01) and body mass index (BMI) was significantly lower (24.9±4.0kg/m2 vs 26.3±4.6kg/m2, p=0.01) in those in Group A compared with those without LA roof line block after cryoballoon ablation (Group B). Compared with those in Group B, cryoballoon application number of LA roof (4.1±1.2 vs 4.5±1.6, p<0.01) and mean nadir of cryoballoon temperature during cryoballoon ablation of LA roof (−44.5±5.6°C vs −40.5±7.5°C, p<0.01) were significantly lower in those in Group A. Regarding cryoballoon application number, the number of the cryoballoon application in which a cryoballoon was applied to LA roof with the guiding catheter located in a left superior pulmonary vein (LSPV) was significantly lower in patients in Group A (1.3±0.8 vs 1.6±1.0, p=0.02), and when the number was less than 2, mean nadir of cryoballoon temperature was significantly lower compared with when it was 2 or more than 2 (−44.8±5.8°C vs −42.8±5.6°C, p<0.01). Among those refer to first ablation procedures, one-year Kaplan-Meier atrial arrhythmias free rate estimates, 80.6% for those in Group A and 59.0% for those in Group B (p<0.01). Multivariate analysis identified LA roof line block without touch up ablation as one of the predictors of atrial arrhythmias recurrences. Atrial tachycardia depending on LA roof occurred after cryoballoon ablation of LA roof in 8 patients, although LA roof line block without touch up ablation could be obtained in the index ablation procedure in 6 patients among them.

Conclusion

LA roof line block could be obtained by solely cryoballoon with a reasonable success rate, especially in those with smaller LAD and lower BMI. To obtaine LA roof line block, cryoballoon ablation with the guiding catheter located in LSPV is preferable. LA roof line block without touch up ablation brings better clinical outcomes in those who underwent cryoballoon ablation of LA roof.

Funding Acknowledgement

Type of funding sources: None.
Effectiveness of various radiofrequency ablation catheters in the treatment of typical atrial flutter
Authors: Gorantla A , Alsaiqali M , Sivakumar S , Francois J , Freytes-Santiago L , Jallad A , Budzikowski A
Published: October 2022

Introduction

Although ablation of typical atrial flutter (AFL) can be easily achieved with radiofrequency energy (RF), there are no studies that compare effectiveness of different ablation catheters. Our study aimed to compare the effectiveness of various types of ablation catheters in the treatment of AFL.

Methods

We analysed patients with AFL who underwent RF ablation by a single operator at our institution. Successful ablation was evidenced by presence of bidirectional conduction block (trans-isthmus conduction time ≥130 ms, or doubling of baseline conduction time, or presence of double potentials ≥90ms). Logistic regression was used to compare success rate and linear regression to compare lesion time.

Results

Out of the 222 patients, only 6 patients did not meet success criteria (2.7%). Catheters used were 8 mm tip in 16 patients, internally irrigated (Chili II Boston Scientific) in 47 patients, externally irrigated (non-force sensing) catheters (CoolPath, Abbott) in 40 patients. Externally irrigated force sensing catheter (Tacticath, Abbott) was used with >10 gm of force and (LPLD) setting (30W-45°C-60 sec) in 50 patients, and high-power short duration (HPSD) setting (50W-43°C −12 sec,) in 70 patients. No complications were encountered. Catheter type had no statistically significant association with ablation success. In terms of lesion time, HPSD catheter statistically significantly shortened lesion time by 758.3s, [CI −1128.29, −388.35s] followed by LPLD by 419.0s [CI −808.49, −29.47s]. Table 1 shows the lesion time difference for the catheters used as compared with 8 mm tip.

Conclusions

Typical atrial flutter radiofrequency ablation procedure had a high success rate, not influenced by type of ablation catheter. Contact force ablation catheter on HPSD is associated with shorter total lesion time.

Funding Acknowledgement

Type of funding sources: None.
Prognostic impact of cavotricuspid isthmus ablation for typical atrial flutter in patients with heart failure and reduced ejection fraction
Authors: Boxhammer E , Bellamine M , Szendey I , Kletzer J , Foresti M , Kraus J , Danmayr F , Topf A , Jirak P , Bonsels M , Lichtenauer M , Hoppe U C , Strohmer B , Motloch L J , Larbig R
Published: October 2022

Background

The CASTLE-AF trial in 2018, showed that pulmonary vein isolation provides a survival benefit and a reduced hospitalization rate in patients with heart failure and concomitant atrial fibrillation. Typical atrial flutter (AFL) can also induce heart failure (tachymyopathy) or, if cardiomyopathy of other origin is prevalent, can further worsen it. Cavotricuspid isthmus ablation (CTI) is a simple, invasive electrophysiological procedure that can effectively treat AFL. Prognostic data on the impact of CTI in patients with heart failure and reduced ejection fraction (HFrEF) is lacking.

Purpose

This study focused on the analysis of the clinical impact of CTI vs. medical therapy in patients with HFrEF.

Methods

The present retrospective, international, multi-center study included 104 patients <85 years with AFL and heart failure (LVEF <50%). 64 patients underwent an electrophysiological study with successful CTI (ablation group), whereas 40 patients received medical therapy alone with frequency or rhythm control and guideline-compliant heart failure therapy (medical therapy group). Patients were followed up for a total of 2 years, with particular emphasis on recording the change in LVEF over time. The primary endpoints were cardiovascular mortality and hospitalization for cardiac causes.

Results

Patients after CTI showed a significant increase in LVEF after 1 year (with the exception of valvular cardiomyopathy). The optimization of LVEF was also reflected in the Kaplan-Meier curves, as the ablation group had a significantly lower 2-year, cardiovascular mortality (p<0.001). The hospitalization rate for cardiac causes in the overall cohort showed a tendency towards reduced hospitalizations (p=0.072). Elderly patients also benefited from CTI in this study. Specifically, Patients ≥70 years of age showed a significantly lower re-hospialization rate after CTI (p=0.043) as well as a significantly reduced mortality after 2 years (p=0.012).

Conclusions

CTI in patients with AFL and HFrEF was associated with significant optimization of LVEF and lower rates of hospitalization and mortality after 2 years. Patient age should not be a primary exclusion criterion for CTI because in this study, patients ≥70 years also benefited significantly from intervention in terms of mortality and hospitalization.

Funding Acknowledgement

Type of funding sources: None.
Outcomes of catheter ablation for typical atrioventricular nodal reentrant tachycardia with low power energy
Authors: Kim M , Oh J K , Yoon Y H , Park H W , Roh J H , Lee J H
Published: October 2022

Background

Atrioventricular nodal reentrant tachycardia (AVNRT) is most common supraventricular tachycardia with acceptable outcome of catheter ablation. However, the serious complication of atrioventricular block (AVB) can occur and affects 0.2% to 2.3% of patients during or after procedures.

Purpose

We hypothesized that slow pathway ablation with 20 watt (W) energy would facilitate acceptable clinical outcomes and low procedure related AVB needed permanent pacemaker.

Methods

Prospective single center trial was performed. Slow pathway ablation was performed in 212 patients (mean age 56.5±18.4 years, 131 women) from January 2017 to May 2020. Twenty watt energy was delivered at the posterior region of the triangle of Koch until accelerated junctional rhythm was obtained.

Results

A total of 212 patients who underwent ablation for typical AVNRT were included. The acute success rate, the mean radiofrequency pulses applied per patient were 98.1% and 8.6±6.6, respectively. Transient AVB occurred in 5 patients (2.4%) and no permanent AVB requiring permanent pacemaker implantation occurred. Those who failed 20 W ablation were younger (success group age vs failed group age 58.2±17.4 vs 31.8±17.9 years, p=0.005) and had a faster heart rate just before slow pathway ablation (success group heart rate vs failed group heart rate 69.2±11.3 vs 76.8±5.6 bpm, p=0.59). The recurrence rate of 20 W ablation was 2.6% and the follow-up period was 18.3±4.1 months.

Conclusion

The low power approach for slow pathway ablation is highly effective and safe. If the heart rate just before ablation is lesser than 70 bpm, slow pathway ablation with 20 W energy could be considered. Further well-designed large-randomized studies are needed to define the role and effect of catheter ablation for typical AVNRT with low power energy.

Funding Acknowledgement

Type of funding sources: None.