Atrial Rate Research Articles

Abstract 4124369: Mid-term Outcomes of Transcatheter Versus Surgical Aortic Valve Replacement in Low to Moderate Risk Patients with Severe Aortic Stenosis: A Meta-analysis of Randomised Clinical Trials

Background: Several clinical trials have demonstrated non-inferiority of transcatheter aortic valve replacement (TAVR) compared with surgical aortic valve replacement (SAVR) in patients with severe aortic stenosis (AS) and low to intermediate surgical risk. However, mid-term results are still contentious. Question: Is TAVR superior to SAVR in the mid-term in terms of mortality outcomes or adverse cardiovascular events? Methods: We searched Embase, Pubmed and Cochrane databases for RCTs that compared TAVR with SAVR in patients with symptomatic severe AS with a follow-up of at least 4 years. Outcomes of interest were all-cause mortality and disabling stroke. Results: We included six RCTs involving 6,444 patients with severe AS, of whom 3,282 (50.9%) underwent TAVR. There was no difference in mortality from all causes (RR 1.08; 95%CI 0.94-1.25; p=0.30; I 2 =45%) and disabling stroke (RR 0.95; 95%CI 0.75-1.21; p=0.67; I 2 =9%) between groups. In the subgroup analysis, 5-year mortality (RR 1.28; 95%CI 1.10-1.49; I 2 =0%) was higher in the TAVI group. The new pacemaker implantation rate was higher in the TAVI group (RR 2.22; 95%CI 1.42-3.45; p=0.0004 ; I 2 =91%). However, new atrial fibrillation rate was higher in the SAVR group (RR 0.42; 95%CI 0.37-0.49; p=0.00001; I 2 =62%). Conclusion: Mid-term mortality and disabling stroke of patients with severe AS treated with TAVR or SAVR were similar.

Abstract 4136983: Estimating Atrial Fibrillation Rate in Patients Using Artificial Intelligence Referenced to Tissue Action Potentials

Background: Ablation by pulmonary vein isolation (PVI) is the most effective approach to treat atrial fibrillation (AF), but 30-40% of patients may not respond. Studies including the CAPLA trial suggest that ablating sites of rapid activation on the posterior left atrial wall or elsewhere may improve success. However, AF rate is rarely calibrated and, since electrograms often include noise or far field activity, may overestimate rate (underestimate cycle length) at many sites. Hypothesis: We hypothesized that artificial intelligence (AI) algorithms may more accurately indicate local AF rate, by excluding spurious activations referenced to simultaneous monophasic action potential (MAP) recordings, compared to conventional measurements. Methods: We studied N=303 AF patients at ablation (68.2±8.0 years, 17.8% females, 72.9% non-paroxysmal AF). Patients were matched N=229 into development and one quarter (N=74) into hold-out test cohorts. Patients underwent AF mapping using multipolar catheters, and a subset with MAP catheters (MedFact, GmbH). We used the development set to train an AI algorithm to reliably detect AF activations, which we compared in the test cohort to a standard dV/dt approach referenced to adjacent MAPs within 2 mm (N=20 patients) and manually annotated activations (N=64 patients). Results: Fig A shows AF in a 66 year old woman, where dV/dt often marked non-physiological activations within repolarization shown in the adjacent MAP. Conversely, the AI system excluded spurious deflections and better correlated with experts (black). In summary, Fig. B shows that AI provided a higher F1 score than dV/dt compared to MAPs (median[IQR]: 0.86 [0.5 - 1] vs. 0.67 [0.40 - 0.73], p<0.01) and experts (0.89 [0.73 - 1] vs. 0.72 [0.60 - 0.89]], p<0.01). Fig C shows that the AI approach better identified AF cycle length (rate; blue) than standard approaches (green) that substantially underestimate cycle length (p<0.05). Conclusions: In this large registry, a novel AI-based approach more accurately detected AF rates in clinical electrograms, referenced to experts and action potential recordings, than standard approaches which overestimated rate. AI may improve characterization of AF activity within the atria.

MYH6 Variants Are Associated with Atrial Dysfunction in Neonates with Hypoplastic Left Heart Syndrome

Background: MYH6 variants are the most well-known genetic risk factor (10%) for hypoplastic left heart syndrome (HLHS) and are associated with decreased cardiac transplant-free survival. MYH6 encodes for α-myosin heavy chain (α-MHC), a contractile protein expressed in the neonatal atria. We therefore assessed atrial function in HLHS patients with MYH6 variants. Methods: We performed a retrospective, blinded assessment of pre-stage I atrial function using 2D speckle-tracking echocardiography (2D-STE). Variant carriers were control-matched based on AV valve anatomy, sex, and birth year. Studies were obtained postnatally from awake patients prior to surgical intervention. Right atrial (RA) and right ventricular (RV) strain and strain rate (SR) were measured from the apical four-chamber view. Results: A total of 19 HLHS patients with MYH6 variants had echocardiograms available; 18 were matched to two controls each, and one had a single control. RA active strain (ASct) was decreased in variant carriers (−1.41%, IQR −2.13, −0.25) vs. controls (−3.53%, IQR −5.53, −1.28; p = 0.008). No significant differences were identified in RV strain between the groups. RA reservoir strain (ASr) and conduit strain (AScd) positively correlated with heart rate (HR) in MYH6 variant carriers only (ASr R = 0.499, p = 0.029; AScd R = 0.469, p = 0.043). RV global longitudinal strain (GLS) as well as RV systolic strain (VSs) and strain rate (VSRs) correlated with HR in controls only (GLS R = 0.325, p = 0.050; VSs R = 0.419, p = 0.010; VSRs R = 0.410, p = 0.012). Conclusions: We identified functional consequences associated with MYH6 variants, a known risk factor for poor outcomes in HLHS. MYH6 variant carriers exhibit impaired RA contractility despite there being no differences in RV function between variant carriers and controls. MYH6 variants are also associated with an ineffective RA reservoir and conduit function at high heart rates, despite preserved RV diastolic function. RA dysfunction and reduced atrial “kick” may therefore be a significant contributor to RV failure and worse clinical outcomes in HLHS patients with MYH6 variants.

Pulsed Field Ablation in Atrial Fibrillation: Initial Experience of the Efficacy and Safety in Pulmonary Vein Isolation and Beyond

Regional differences in pulsed field ablation (PFA) adoption for pulmonary vein isolation (PVI) with additional posterior wall ablation (PWA) in Asia remains unknown. We hereby report our experience on the safety and efficacy of PFA in AF ablation. Consecutive AF patients who underwent PFA from September 2022 to January 2024 were included. The primary efficacy endpoint was freedom from atrial arrhythmia recurrence after a 90-day blanking period at 12 months. Safety endpoints included 30 days of all-cause death, cardiac tamponade, stroke, myocardial infarction, and heart failure hospitalization. One hundred and one (72.3% males, 79.2% pAF) patients underwent PFA for AF. Thirty-one (30.7%) had structural heart disease with mean LVEF of 57.4 ± 8.1% and CHA2DS2-VASc score of 1.4 ± 1.3. Twenty-nine (28.7%) underwent additional PWA (PVI + PWA) using PFA. PWA was acutely successful in all patients. Patients who underwent PWA were more likely to have persistent AF and require general anesthesia and electroanatomic mapping (all p < 0.05). Total PFA applications for PVI, LA dwell time, procedural time, and fluoroscopy time were similar between the PVI-only and PVI + PWA groups (all p > 0.05). The 1-year atrial arrhythmia recurrence rates were 10% for pAF and 21% for the persistent AF group. The primary efficacy endpoint was not significantly different between the PVI-only and PVI+PWA groups (12-month KM estimates 90.3% [95% CI, 83.3–97.3] and 82.8% [95% CI, 68.1–97.4], respectively). There were no complications related to PFA use. PFA can be safely, effectively, and efficiently adopted for AF ablation. Additional PWA, if pursued, had similar procedural metrics to the PVI-only strategy without increased complications.

Normal ranges of left atrial phasic strains and strain rates by 2D speckle-tracking echocardiography in pediatrics: a systematic review and meta-analysis

Establishing normal values of left atrial (LA) phasic strains and strain rates is essential for distinguishing between normal and abnormal functions, determining the degree of abnormality, and understanding the clinical significance of reported values in pediatrics. This meta-analysis aimed to establish normal values of two-dimensional speckle-tracking echocardiography (2DSTE)-derived LA phasic strains and strain rates in the pediatric population and identify the sources of inter-study heterogeneity for these values. A comprehensive search of PubMed, Scopus, and Embase databases was conducted using keywords such as “left atrial/left atrium,” “strain/speckle/deformation,” and “echocardiography” combined with pediatric age categories. Inclusion criteria comprised English-language human studies involving healthy subjects under 18 years of age. Subjects were categorized as neonates (up to 1 month), infants (1–12 months), and children (1–18 years). A random-effects model was applied to determine 2DSTE-derived LA strains and strain rates, and a meta-regression analysis was performed to investigate inter-study heterogeneity. Our analysis included 17 studies involving 1448 healthy subjects. For children, the mean values of LA strains during the reservoir, conduit, and contraction phases were 47.3% (95% CI 42.5–52.1%), 32.8% (95% CI 27.8–37.8%), and 12% (95% CI 10.0–14.1%), respectively. The mean values for LA strain rates were 2.4 s−1 (95% CI 1.1–3.8 s−1), 4.3 s−1 (95% CI 0.6–8.0 s−1), and 2.4 s−1 (95% CI 0.4–4.5 s−1), respectively. Inter-study heterogeneity for 2DSTE-derived LA phasic strains and strain rates was attributed to factors such as the number of study participants, publication year, software utilized, gating methods, the number of analyzed segments, the geographical region of the study, and heart rate. This study established the normal range of 2DSTE-derived LA phasic strains and strain rates. Additionally, inter-study heterogeneity was found to be influenced by various demographic, physiologic, and methodological factors.

Identifying at-risk patients for atrial high-rate episodes by machine learning

Abstract Background Current evidence suggests that atrial high rate episodes (AHRE)/subclinical atrial fibrillation (AF) are associated with increasing risk of clinical AF, and subsequently, ischaemic stroke and other adverse cardiovascular events. Purpose To construct a high-performance model by machine learning (ML) for the prediction of AHRE detected by a cardiac implantable electronic device (CIED) capable of atrial sensing in a European cohort. Methods We utilized data from a prospective cohort of patients with CIED. AHRE was defined as an episode lasting at least 5 minutes with atrial rate ≥ 175 beats per minute. We divided the cohort into training and internal validation cohorts in 7:3 and used 5-fold cross-validation in the training cohort to assess model performance and prevent model overfitting. Pre-selected features were imported into eight common ML algorithms to predict AHRE, including light gradient boosting machine (LightGBM), random forest (RF), logistic regression, support vector machine, multiple perceptron, eXtreme gradient boosting machine (XGBoost), Gaussian naïve Bayes, and K nearest neighbours. The importance ranking of the features was interpreted by calculating the SHapley Additive exPlanationation (SHAP) value for each feature within the optimal model. Results A total of 500 consecutive patients with CIEDs (mean age 70.2±13.3; 39.2% female) were included. Of these, 164 patients (32.8%) were found to have AHRE. Among all ML models, RF was the best performing model, which obtained the highest AUC (0.738), recall (0.673) and F1-score (0.584) in the internal validation cohort. The results of SHAP showed that antiplatelet, statin, age, white blood cell count, and cardiomyopathy were the first five important features, indicating that the RF model had good interpretability and reliability. Conclusion Our study is the first to demonstrate in a European cohort the effectiveness and feasibility of ML algorithms in predicting AHRE in patients detected by CIEDs. The best RF models require further external validation to assess generalizability to other cohorts.Figure 1Figure 2

No improvement in atrial arrhythmia rates in patients on baroreflex activation therapy

Abstract Background Atrial arrhythmias encompass a wide range of abnormal cardiac rhythms including atrial fibrillation, atrial flutter, and atrial tachycardia. Patients with heart failure with reduced ejection fraction (HFrEF) have increased risk of atrial arrhythmias, ultimately leading to increased morbidity. Baroreflex Activation Therapy (BAT) employs an implantable device to increase parasympathetic nervous system activity by stimulating the carotid baroreceptors thereby reducing afterload and heart failure symptoms. In our prior study, BAT therapy has been shown to reduce hospitalization rates in patients with HFrEF. However, the effects of BAT on atrial arrhythmia has never been studied. Objective In this study, we analyzed the effects of BAT on atrial arrhythmia rates in patients with HFrEF. Methods Patients with HFrEF with BAT therapy for at least 12-months at a hospital were retrospectively studied. Inclusion criteria includes implantable cardioverter-defibrillator (ICD) placement of at least 12-months pre- and post-BAT therapy. Additionally, patients diagnosed with atrial arrhythmias prior to the study timeline were excluded. Atrial arrhythmia rates 6 and 12-months pre-BAT therapy and 6 and 12-months post-BAT therapy were compared. Atrial arrhythmia episodes were recorded through ICD interrogation every 1-3 months in the clinic. Of the 31 identified patients on BAT therapy, 11 patients fit the inclusion criteria. For the 11 patients in the study, 3 identified as female and 8 identified as male, 6 identified as white, 4 identified as Hispanic, and 1 identified as African-American with a mean age of 59.8 ± 17.4 years. The average left ventricular ejection fraction pre-BAT therapy was 23.8 ± 10.8%. Results The mean average atrial arrhythmia rates for 6-month pre-BAT therapy and 6-month post-BAT therapy were 0.12/month ± 0.40 and 1.32/month ± 2.76 respectively (p=0.18), suggesting no differences in atrial arrhythmia rates at 6-months with BAT therapy. The mean average atrial arrhythmia rates for 12-month pre-BAT therapy and 12-month post-BAT therapy were 0.11/month ± 0.35 and 2.40/month ± 5.84 respectively (p=0.22), suggesting no differences in atrial arrhythmia rates at 12-months with BAT therapy. Conclusion Although BAT therapy has been shown to decrease hospitalization rates, BAT therapy is not associated with decreased atrial arrhythmia rates at 6 months and 12 months.

Atrial rates during treated ventricular tachycardia in patients with implantable cardioverter defibrillators: clinical implications of a vagal sinus node response

Abstract Introduction Autonomic tone plays an important role in the genesis and sustenance of ventricular tachycardia (VT). Whilst sympathetic hyperactivity is an established driver of ventricular arrhythmias, sinus node response during VT varies broadly between patients, and can be paradoxical. Purpose We hypothesized that device-detected changes in sinus node rate could be an important surrogate of the autonomic response to VT, and may exert significant – and potentially modifiable – haemodynamic consequences independent of ventricular activity. Methods Device electrograms were analysed from consecutive patients with dual chamber implantable cardioverter defibrillators (ICDs) requiring anti-tachycardia pacing (ATP) or defibrillation for sustained monomorphic VT. Atrial rates were measured before VT onset (‘baseline’) and again at the point of detection by the device. Sinus node response was characterized as ‘stable’ (atrial rate remained within 10% of baseline), ‘sympathetic’ (atrial rate increased >10%) or ‘vagal’ (atrial rate decreased >10%). Patients who did not maintain ventriculoatrial dissociation or who presented in atrial tachyarrhythmia were excluded. Symptoms and electrical response to ICD therapies were recorded. Results 172 treated episodes of VT were included from 97 patients (median age: 69 years, 65% male, 31% ischaemic cardiomyopathy, median ventricular rate: 205bpm, median ejection fraction: 30%). Sinus node response was stable in 55%, sympathetic in 24% and vagal in 21%. A vagal response was associated with ATP-refractory VT (OR: 2.2 (1.1-4.8) p=0.03) and, when adjusting for ventricular rate, was independently associated with symptoms of presyncope or syncope (adjusted OR: 6 (2.7-13.7), p<0.0001). Conclusions This preliminary analysis suggests that a vagal sinus node response during VT is associated with adverse outcomes in ICD patients. Vagolytic therapy has recently been demonstrated to improve haemodynamic tolerance during VT ablation; whether supportive atrial pacing during VT could mitigate symptoms and potentiate arrhythmia termination in ICD patients warrants further exploration. Figure 1: Change in sinus node rate during sustained monomorphic ventricular tachycardia in patients with dual chamber ICDs, stratified by the occurrence of presyncopal symptoms or syncopeFigure 1

Incidence of silent brain injury in pacemaker implanted patients with atrial high-speed episodes (AHRE)

Abstract Purpose Atrial high rate episodes (AHRE) are tachyarrhythmia attacks that can be detected by implantable cardiac devices. In the European Society of Cardiology (ESC) 2020 AF guideline, AHRE is defined as ≥ 175 bpm for the device-programmed rate criterion and ≥ 5 minutes for the duration criterion. AHRE has been shown to be one of the predisposing factors of AF and stroke. However, the relationship between AHRE and SBI has not been clarified yet. Neuron spesific enolase (NSE) is a valid biomarker for quantifying the volume of neuronal damage. In this study, we aimed to evaluate the incidence of silent brain injury (SBI), defined as elevated NSE levels in AHRE detected patients. Method Between January 2021 and June 2022, 80 patients who underwent routine pacemaker control, met the inclusion and exclusion criteria, and had AHRE detected in their permanent pacemaker records were included in a university faculty of medicine cardiology arrhythmia polyclinic. For the control group, patients who had a permanent pacemaker and did not have AHRE or any other arrhythmia were included. Of patients with AHRE detected in the last 6 months and those who had an AHRE attack within the last 72 hours were examined. Results Individuals included in the study were divided into subgroups according to AHRE duration. Group 1 (non-AHRE) 80 (50.0%), Group 2 (AHRE lasting <5 min) 24 (15.0%), Group 3 (≥5 min - <1h) 33 (20.6%), 19 (11.9%) patients in Group 4 (lasting ≥1 h - <24 h) and 4 (2.5%) patients in Group 5 (lasting ≥24 h). There was a statistically significant difference in NSE median values between groups (p=<0.001). In Mann Whitney U test with Bonferronni correction, the median values of all other groups were significantly different from each other (p=<0.001). In the correlational analysis, there was a statistically significant positive relationship between AHRE duration and NSE values (r=0.842; p=<0.001). Additionally, there was correlation between AHRE duration and age (r=0.235; p=0.036), CHA2DS2-VASc score (r=0.226, p=0.044) and LA diameter (r=0.300; p=0.007). NSE levels were positively correlated with AHRE duration (r=0.842; p=<0.001) and LA diameter (r=0.242; p=0.030). Conclusion AHRE duration was longer in patients with advanced age, increased CHA2DS2-VASc score, and increased LA diameter. This may play a role in explaining the underlying pathophysiological changes in AHRE before AF develops. Since NSE levels are related to LA diameter as well as AHRE duration, it can be thought that increasing LA diameter contributes to the development of thrombus.

Atrial fibrillation recurrence rates in patients with transthyretin cardiac amyloidosis undergoing pulmonary vein isolation: a comparative retrospective study with propensity score matching

Abstract Background Atrial fibrillation (AF) affects up to 70% of individuals diagnosed with transthyretin cardiac amyloidosis (ATTR CA) [1]. AF ablation is frequently considered in the management of these patients, but there is a lack of data about outcomes of the procedure in this population. Purpose This study aims to evaluate AF recurrence rates and long-term AF recurrence-free survival in patients with ATTR CA undergoing pulmonary vein isolation (PVI). Methods A single-center retrospective study was conducted, including all patients diagnosed with ATTR CA who underwent PVI from 2016 to 2023. We compared patients with amyloidosis (cases) to those without (controls), employing propensity score matching for age, gender, AF type (paroxysmal vs. persistent), BMI, diabetes, arterial hypertension diagnosis, antiarrhythmic drug therapy post-index ablation, and left atrium (LA) volume assessed by 3D rotational angiography (3DRA). Results 16 patients with CA were matched to 16 patients without (32 patients in total). After matching, the populations demonstrated comparable baseline characteristics (figure 1). The study consistently revealed a higher AF recurrence rate, after PVI, in the CA group (81.3%) compared to the control group (37.5%) at the last follow-up (p-value 0.01) (median follow-up 1255 ± 1055 days in CA and 1491 ± 464 days in control group), as well as a significantly lower long-term AF-recurrence free survival (log-rank p = 0.01 – figure 2). Additionally, the recurrence rate at 1-year post-procedure was 56.25% in the CA group and 18.75% in the control group (p-value 0.03). Conclusions Pulmonary vein isolation remains a viable treatment option for individuals with ATTR CA. However, it proved less effective (or less durable) than in the general population without the disease, both at 1-year follow-up and for longer periods, as shown also with recurrence-free survival rate. Further studies are warranted to determine the optimal treatment strategy for this specific population.Baseline Characteristics fig. 1Kaplan Meyer fig. 2

Lesion size index-guided radiofrequency catheter ablation using an impedance-based three-dimensional mapping system to treat sustained atrial tachycardia in a horse.

Sustained atrial tachycardia at an atrial rate of 191/min on the surface ECG was detected in a 6-year-old Warmblood mare. The vectorcardiogram obtained from a 12-lead ECG suggested a caudo-dorsal right atrial origin of the arrhythmia. Impedance-based three-dimensional electro-anatomical mapping, using the EnSite™ Precision Cardiac Mapping System revealed a clockwise macro-reentry around a line of conduction block in the caudomedial right atrium. Ten radiofrequency applications were applied to isolate the caudal vena cava myocardial sleeves at a power of 35 W and mean contact force of 14 ± 3 g until a lesion size index of 6 was reached. Sinus rhythm was restored at the first energy application. Successful isolation was confirmed by demonstrating entrance and exit block. Holter monitoring 5 days post-ablation revealed no abnormalities. To date, 9 months after treatment, no recurrence has been observed. The use of lesion size index-guided ablation and isolation of the arrhythmogenic substrate in the caudal vena cava may minimise the risk of recurrence.

The negative chronotropic effects of (±)-propranolol and (±)-4-NO2-propranolol in the rat isolated right atrium are due to blockade of the 6-nitrodopamine receptor.

The positive chronotropic action induced by 6-nitrodopamine (6-ND) is selectively blocked by β1-adrenoceptor antagonists at concentrations that do not affect the positive chronotropic effect induced by dopamine, noradrenaline, and adrenaline. Here, the effects of ( ±)-propranolol, ( ±)-4-NO2-propranolol, and ( ±)-7-NO2-propranolol were investigated in the rat isolated right atrium. The atrium was mounted in glass chambers containing gassed (95%O2:5%CO2) and warmed (37°C) Krebs-Henseleit's solution, and the isometric tension registered (PowerLab system). ( ±)-Propranolol, ( ±)-4-NO2-propranolol, and ( ±)-7-NO2-propranolol caused concentration-dependent falls in the spontaneous atrial frequency (pIC50: 4.80 ± 0.10, 4.64 ± 0.10, and 4.95 ± 0.10, respectively). The calculated pA2 values for ( ±)-propranolol, ( ±)-4-NO2-propranolol, and ( ±)-7-NO2-propranol on noradrenaline-induced positive chronotropism were 8.44 ± 0.08, 6.41 ± 0.07, and 9.21 ± 0.29, respectively. The positive chronotropism induced by 6-ND (10pM) was blocked by ( ±)-propranolol (1µM) and ( ±)-4-NO2-propranolol (30nM), whereas ( ±)-7-NO2-propranolol (1µM) had no effect on 6-ND-induced responses. The pIC50 of ( ±)-propranolol, ( ±)-4-NO2-propranolol, and ( ±)-7-NO2-propranolol were significantly shifted to the right in L-NAME-treated atria. The discrepancy between pA2 values of ( ±)-propranolol and its respective pIC50 indicates that the falls in atrial rate induced by ( ±)-propranolol should not be attributed to b-adrenergic antagonism. The reduced chronotropism by ( ±)-propranolol was unaffected by the sodium channel inhibitors tetrodotoxin and lidocaine but that was abolished in atria pre-treated with ( ±)-4-NO2-propranolol. The finding that ( ±)-propranolol reduces spontaneous atrial rate only in concentrations that affect 6-ND-induced positive chronotropism confirms the role of this catecholamine as an endogenous modulator of heart chronotropism. ( ±)-4-NO2-Propranolol behaves as a selective antagonist of 6-ND in the rat isolated atrium.

Pulsed Field Ablation to Treat Paroxysmal Atrial Fibrillation: Safety and Effectiveness in the AdmIRE Pivotal Trial.

Evidence from clinical trials of early pulsed field ablation (PFA) systems in treating atrial fibrillation has demonstrated their promising potential to reduce complications associated with conventional thermal modalities while maintaining efficacy. However, the lack of a fully integrated mapping system, a staple technology of most modern electrophysiology procedures, poses limitations in lesion creation and workflow options. A novel variable-loop PFA catheter integrated with an electroanatomic mapping system has been developed that allows for real-time nonfluoroscopic procedural guidance and lesion indexing as well as feedback of tissue-to-catheter proximity. AdmIRE (Assessment of Safety and Effectiveness in Treatment Management of Atrial Fibrillation With the Bosense-Webster Irreversible Electroporation Ablation System), a multicenter, single-arm, Food and Drug Administration investigational device exemption study, evaluated the long-term safety and effectiveness of this integrated PFA system in a large United States-based drug-refractory symptomatic paroxysmal atrial fibrillation patient population. Using the PFA catheter with a compatible electroanatomic mapping system, patients with drug-refractory symptomatic paroxysmal atrial fibrillation underwent pulmonary vein isolation. The primary safety end point was primary adverse event within 7 days of ablation. The primary effectiveness end point was a composite end point that included 12-month freedom from documented atrial tachyarrhythmia (ie, atrial fibrillation, atrial tachycardia, atrial flutter) episodes, failure to achieve pulmonary vein isolation, use of a nonstudy catheter for pulmonary vein isolation, repeat procedure (except for one redo during blanking), taking a new or previously failed class I or III antiarrhythmic drug at higher dose after blanking, or direct current cardioversion after blanking. At 30 centers, 277 patients with paroxysmal atrial fibrillation (61.5±10.3 years of age; 64.3% male) in the pivotal cohort underwent PFA. More than 25% of the procedures were performed without fluoroscopy. Median (Q1, Q3) pulmonary vein isolation procedure, fluoroscopy, and transpired PFA application times were 81.0 (61.0, 112.0), 7.1 (0.00, 14.3), and 31.0 (24.8, 40.9) minutes, respectively. The primary adverse event rate was 2.9% (8 of 272), with the most common complication being pericardial tamponade. The 12-month primary effectiveness end point was 74.6%. The 1-year freedom from atrial fibrillation, atrial tachycardia, or atrial flutter recurrence rate after blanking was 75.4%. Substantial improvements in quality of life were observed as early as 3 months after the procedure, concurrent with a reduction in multiple health care use measures. AdmIRE confirmed the safety and effectiveness of the variable-loop PFA catheter, with short procedure and PFA application times and low fluoroscopy exposure. URL: https://www.clinicaltrials.gov; Unique identifier: NCT05293639.

. The significance of serum sST2 and cfDNA in children with severe pneumonia complicated by myocardial damage

Objective: The paper aimed to explore the significance of serum sST2 and cfDNA to prevent atrial inflammation in children with severe pneumonia complicated by myocardial damage. Methods: 120 children with severe pneumonia complicated by myocardial damage who were treated in the Children's Department of the author's hospital from April 2021 to December 2023 were recruited as research subjects. The children were randomly divided into two groups, one group of 60 children received personalized care intervention based on serum sST2 and cfDNA (personalized care group), and the other group of 60 children received routine care (routine care group). The clinical data of the two groups of patients were compared. The changes in serum sST2 and cfDNA levels of patients were compared before and after care. ELISA kits were used to test atrial inflammation marker levels before and after patient care. The patient's cardiac function was assessed through cardiac ultrasound. the nursing intervention effects of the two groups was compared. The patient satisfaction with nursing care was compared between the two groups. Results: There was no distinction in the general record of the two groups (P>0.05). Before care, there was no distinction in serum sST2 and cfDNA levels between the two groups (P>0.05). After care, the serum sST2 and cfDNA levels in the personalized care group were lower than those in the routine care group (P<0.05). There was no difference in CRP, cTn, 1L-6 and TNF-α between the two groups before nursing (P>0.05). After nursing, the levels of CRP, cTn, 1L-6 and TNF-α in personalized nursing were lower than those in the conventional nursing group (P<0.05). Parameters such as EF and E/A in the personalized care group were higher than those in the routine care group (P<0.05). The LVEDd and LVESd in the personalized care group were smaller than routine care group (P<0.05). The improvement rate of cardiac function, remission rate of atrial inflammation and 6-month re-hospitalization rate in the personalized care group were lower than conventional care group (P<0.05). The very satisfied rate in the personalized care group was higher than routine care group (P<0.05), and the dissatisfaction rate in the personalized care group was lower than routine care group (P<0.05). Conclusion: Personalized nursing intervention based on serum sST2 and cfDNA can significantly improve the cardiac function of children with severe pneumonia complicated by myocardial damage, reduce the levels of atrial inflammation markers, and advance the satisfaction of children and their families. These findings underscore the importance of applying serum sST2 and cfDNA monitoring in clinical care and the significant benefits of personalized care in preventing atrial inflammation, improving heart health, and improving patient quality of life.

The prognostic value of left atrial strain and strain rate in predicting heart failure outcomes in patients with hypertrophic cardiomyopathy and a left ventricular ejection fraction of 50% or higher

The prognostic value of left atrial strain and strain rate in predicting heart failure outcomes in patients with hypertrophic cardiomyopathy and a left ventricular ejection fraction of 50% or higher

Isolated non-immune-mediated second-degree atrioventricular block in the fetus: natural history and predictive factors for spontaneous recovery.

To determine the clinical course of fetal isolated non-immune-mediated second-degree atrioventricular block (AVB) and the factors associated with spontaneous recovery in these cases. Fetuses with isolated non-immune-mediated second-degree AVB were recruited prospectively between 2014 and 2022. These fetuses were divided into two groups: those which recovered spontaneously and those which did not. Maternal and fetal characteristics and intrauterine and postnatal outcomes were compared between the two groups. The study cohort included 20 fetuses with isolated non-immune-mediated second-degree AVB, diagnosed at a median gestational age of 22.0 (range, 17.0-35.0) weeks. In 12 fetuses, 1:1 atrioventricular conduction was restored spontaneously in utero and there was no recurrence during the postnatal follow-up period. In the remaining eight fetuses, second-degree AVB was maintained and, in six of these, the pregnancy was terminated on parental request. Of the two liveborn children who had persistent second-degree AVB prenatally, one had progressed to complete AVB at the latest follow-up, at the age of 34 months, but was asymptomatic, without heart enlargement or dysfunction. The other child progressed to complete AVB after delivery and was diagnosed with type-2 long QT syndrome. This infant died aged 2 months. Fetuses in the group that recovered spontaneously had earlier gestational age at diagnosis (median, 20.0 (range, 17.0-26.0) vs 24.5 (range, 18.0-35.0) weeks; P = 0.004) and higher atrial rate at diagnosis (median, 147 (range, 130-160) vs 138 (range, 125-149) bpm; P = 0.006) in comparison with the group that did not recover spontaneously. The best cut-off values for prediction of failure to recover spontaneously were 22.5 weeks' gestational age at diagnosis and 144 bpm atrial rate at diagnosis, with sensitivities of 87.5% and 75.0%, respectively, and specificities of 92.0% and 87.5%, respectively. The outcome of 60% of fetuses with isolated non-immune-mediated second-degree AVB was favorable. Earlier gestational age and higher atrial rate at diagnosis were associated with spontaneous reversion to normal sinus rhythm. Prenatal genetic testing should be performed in cases with persistent AVB, to exclude heritable disorders including long QT syndrome. These findings provide important information for clinical management and prenatal counseling in these cases. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

Atrial refractoriness early after transcatheter aortic valve implantation TAVI in patients with severe aortic stenosis and sinus rhythm.

Aortic valve stenosis (AS) is a common valvular heart disease, especially in the elderly, and is associated with a high prevalence of atrial fibrillation. Although the risk of atrial fibrillation is expected to decrease after the intervention, atrial fibrillation develops in many patients undergoing surgical or percutaneous transaortic valve implantation. We aimed to evaluate atrial refractoriness since it may play a key role in the occurrence of atrial fibrillation after transaortic valve implantation. Seventy-nine consecutive patients who underwent TAVI between October 2021 and May 2023 were enrolled in this trial. Sixty-seven patients underwent electrophysiology study before and after TAVI. We evaluated the changes in PA and AH intervals, as well as atrial effective refractory periods. Besides the hemodynamic changes, atrial effective refractory periods increased, and atrial effective refractory period dispersion (39.8±21.6 vs. 31.1±18.0) decreased significantly after TAVI. The change in atrial effective refractory period dispersion after TAVI was correlated only with the changes in left ventricular end-diastolic pressure (r=0.77, P=0.001) and the changes in aortic gradient (r=0.4, P=0.001). The independent variables affecting the changes in atrial effective refractory period dispersion were basal pro-BNP levels, besides the changes in left ventricular end-diastolic pressure and aortic gradient after transaortic valve implantation. Our results show an acute improvement in atrial refractoriness after TAVI, though high atrial fibrillation rates are reported in the literature. The timing of aortic valve replacement is important, as irreversible maladaptive changes might have already developed by the time of intervention.

Clinical and perfusion imaging characteristics of acute large vessel occlusion in intracranial atherosclerosis

ObjectivesThis study aimed to compare clinical and perfusion imaging profiles in acute ischemic stroke with large vessel occlusion (AIS-LVO) between patients with intracranial atherosclerotic disease (ICAD) and non-ICAD who underwent endovascular treatment (EVT). MethodsData from AIS-LVO patients over the anterior circulation undergoing EVT across two stroke centers were retrospectively analyzed. Clinical profiles and perfusion parameters from automated processing of perfusion imaging were compared between ICAD and non-ICAD groups. Ischemic core was defined as relative cerebral blood flow < 30 % on CT perfusion or apparent diffusion coefficient ≤ 620 × 10−6 mm2/s on MR diffusion weighted imaging. ResultsA total of 111 patients were included (46 ICAD, 65 non-ICAD). The ICAD group exhibited a higher male proportion (60.9 % vs. 35.4 %), more M1 segment occlusions (78.3 % vs. 56.9 %), lower atrial fibrillation rates (17.4 % vs. 63.1 %), and lower baseline NIH Stroke Scale (NIHSS) scores (median [IQR]: 13 [8.75-18] vs. 15 [10-21]) at presentation compared to non-ICAD (all p < 0.05). However, there was no difference in NIHSS scores at discharge or in good functional outcomes (modified Rankin Scale 0-2) at 3 months between the two groups. ICAD patients also had smaller median ischemic core volumes (0 [IQR 0-9.7] vs. 4.4 [0-21.6] ml, p = 0.038), smaller median Tmax >6s tissue volulmes (89.3 [IQR 51.1-147.1] vs. 124.4 [80.5-178.6] ml, p = 0.017) and lower median HIR (hypoperfusion intensity ratio defined as Tmax >10s divided by Tmax >6s; 0.28 [IQR 0.09-0.42] vs. 0.44 [0.24-0.60], p = 0.003). Higher baseline NIHSS scores correlated with larger Tmax >6s lesion volumes as well as higher HIR value in non-ICAD patients, but not in ICAD patients. ConclusionsIn anterior circulation of AIS-LVO, ICAD patients exhibited distinct clinical presentations and perfusion imaging characteristics when compared to non-ICAD patients. Perfusion imaging profiles may serve as indicators for identifying ICAD patients before EVT.

Analysis of predictors of hemorrhagic transformation after reperfusion therapy with recombinant tissue plasminogen activator in patients with acute ischemic stroke: a single-center experience

BackgroundHemorrhagic transformation (HT) is a serious complication of thrombolytic therapy for acute ischemic stroke, limiting its indications and affecting treatment plans and clinical prognosis. Identifying risk factors for HT could help improve the risk–benefit ratio of thrombolytic therapy. We aimed to analyze the predictors of HT after reperfusion therapy with recombinant tissue plasminogen activator (rTPA) in patients with acute ischemic stroke. This study included 115 patients who received rTPA. All patients underwent history taking, clinical examination, neurological examination including Glasgow Coma Scale and National Institutes of Health Stroke Scale scores (NIHSS), radiological investigation, and cardiac investigation. Patients were followed up strictly every 2 h for 1st 24 h then for two weeks clinically using the NIHSS and radiologically using CT or MRI to detect HT.ResultsPatients with HT represented 21.7% of all patients receiving rTPA, while symptomatic intracranial hemorrhage (sICH) represented 6.9%. Patients with HT had significantly higher blood pressure, respiratory rate, atrial fibrillation rate, NIHSS score, INR, prothrombin time, neutrophil-to-lymphocyte ratio (NLR), and lower platelet count, LDL level, higher Fazekas score, lower ASPECT score, and prolonged onset-to-needle time.ConclusionPredicting HT in acute ischemic stroke patients is crucial for optimizing management and potentially improving outcomes. In our study, six predictors were associated with HT: higher respiratory rate, higher atrial fibrillation rate, higher NLR, lower LDL level, higher Fazekas score, lower ASPECT score, and onset-to-needle time greater than 180 min.

Evaluation of Left Ventricular Remodeling and Prognosis after PCI in Acute Myocardial Infarction Using Real-Time, Three-Dimensional Echocardiography Combined with Layer-Specific Strain Imaging

Aim: This study aimed to evaluate left atrial and left ventricular volumes, strains, and strain rates in patients with acute ST-segment elevation myocardial infarction (STEMI) treated with percutaneous coronary intervention (PCI) using real-time three-dimensional echocardiography and layer-specific strain techniques. The relationships between these parameters and left ventricular remodeling (LVR) and prognosis were also explored. Methods: The study included 217 patients with first-episode STEMI who underwent emergency PCI. Echocardiography and myocardial strain analyses were performed within 24 h post-PCI. Patients were categorized into early and non-early LVR groups based on the increase in left ventricular end-diastolic volume (LVEDV). The occurrence of major cardiovascular adverse events (MACE) was followed up for one-year post-PCI. Differences in clinical data and ultrasound parameters between the groups were compared, and the predictive value of myocardial strain indicators for late LVR was analyzed using a multivariate logistic regression model and receiver operating characteristic (ROC) curves. Results: Early LVR occurred in 54.8% of patients and was characterized by decreased left ventricular systolic function, more segments with abnormal movement, and reduced absolute strain values in the three layers of the left ventricular wall myocardium, with a compensatory increase in left atrial strain rate during the contraction phase. The early LVR group showed a higher incidence of MACE at the one-year follow-up. At 6 months post-PCI, 29.9% of patients developed late LVR, which was not completely related to early LVR. Late LVR was associated with a higher incidence of MACE. The longitudinal strain value of each layer of left ventricular myocardium obtained from layer-specific strain imaging showed predictive value for advanced LVR. Conclusions: More than half of patients with STEMI develop early LVR post-PCI, with a higher incidence of MACE during one-year of follow-up, necessitating attention to early LVR in clinical practice. Late LVR, which develops in some patients after 6 months, is also linked to a higher incidence of MACE. Accurate monitoring of the myocardial deformation function using layer-specific strain imaging is expected to become a reference indicator for clinical diagnosis and treatment. Monitoring the structure and function of the left atrium and mitral valve alongside the LVR is important for prognostic assessment and for formulating diagnostic and treatment plans.