A zero-exchange approach for left atrial access in pulmonary vein isolation with pulsed field ablation.

INTRODUCTION: Pulsed field ablation (PFA) has emerged as an innovative technique for pulmonary vein isolation (PVI). Typically, a transeptal puncture (TSP) with a standard sheath precedes a switch to the larger diameter sheath in the left atrium. This study aimed to describe the safety and feasibility of direct TSP using the large diameter Faradrive sheath before performing PVI with PFA. METHODS: We prospectively enrolled 166 consecutive patients with paroxysmal or persistent atrial fibrillation (AF) undergoing PVI with PFA at our institution. TSP was performed in all cases with transesophageal echocardiography guidance, using the Faradrive sheath and a 98 cm matched Brockenbrough needle. The primary endpoint was the occurrence of pericardial tamponade during or within the first 48 h after the procedure. The secondary endpoint was the occurrence of any major complication. RESULTS: All 166 patients were included into the final analysis (44% female): 64% of patients had paroxysmal AF and 36% persistent AF (68 ± 11 years old, median CHA2DS2Vasc Score 3, median left atrial volume index 31). The median duration of the procedure was 60 min, median time to TSP was 15 min, and the median fluoroscopy dose was 595 cGy × cm2. The primary endpoint occurred in one patient: a non-TSP related pericardial tamponade, which was managed with pericardial puncture. CONCLUSION: Direct TSP with skipping sheath exchange using the large diameter Faradrive sheath for PVI with PFA was safe, feasible, and reduced costs in all patients. Large scale studies and registries are needed to verify this workflow.

Improving Valvular Pathologies and Ventricular Dysfunction Diagnostic Efficiency Using Combined Auscultation and Electrocardiography Data: A Multimodal AI Approach.

Simple sensor-based procedures, including auscultation and electrocardiography (ECG), can facilitate early diagnosis of valvular diseases, resulting in timely treatment. This study assessed the impact of combining these sensor-based procedures with machine learning on diagnosing valvular abnormalities and ventricular dysfunction. Data from auscultation at three distinct locations and 12-lead ECGs were collected from 1052 patients undergoing echocardiography. An independent cohort of 103 patients was used for clinical validation. These patients were screened for severe aortic stenosis (AS), severe mitral regurgitation (MR), and left ventricular dysfunction (LVD) with ejection fractions ≤ 40%. Optimal neural networks were identified by a fourfold cross-validation training process using heart sounds and various ECG leads, and their outputs were combined using a stacking technique. This composite sensor model had high diagnostic efficiency (area under the receiver operating characteristic curve (AUC) values: AS, 0.93; MR, 0.80; LVD, 0.75). Notably, the contribution of individual sensors to disease detection was found to be disease-specific, underscoring the synergistic potential of the sensor fusion approach. Thus, machine learning models that integrate auscultation and ECG can efficiently detect conditions typically diagnosed via imaging. Moreover, this study highlights the potential of multimodal artificial intelligence applications.

Wide Antral Circumferential Re-Ablation for Recurrent Atrial Fibrillation after Prior Pulmonary Vein Isolation Guided by High-Density Mapping Increases Freedom from Atrial Arrhythmias.

Performing repeated pulmonary vein isolation (re-PVI) after recurrent atrial fibrillation (AF) following prior PVI is a standard procedure. However, no consensus exists regarding the most effective approach in redo procedures. We assessed the efficacy of re-PVI using wide antral circumferential re-ablation (WACA) supported by high-density electroanatomical mapping (HDM) as compared to conventional re-PVI. Consecutive patients with AF recurrences showing true PV reconnection (residual intra-PV and PV antral electrical potentials within the initial ablation line) or exclusive PV antral potentials (without intra-PV potentials) in the redo procedure were prospectively enrolled and received HDM-guided WACA (Re-WACA group). Conventional re-PVI patients treated using pure ostial gap ablation guided by a circular mapping catheter served as a historical control (Re-PVI group). Patients with durable PVI and no antral PV potentials were excluded. Arrhythmia recurrences ≥30 s were calculated as recurrences. In total, 114 patients were investigated (Re-WACA: n = 56, 68 ± 10 years, Re-PVI: n = 58, 65 ± 10 years). There were no significant differences in clinical characteristics including the AF type or the number of previous PVIs. In the Re-WACA group, 11% of patients showed electrical potentials only in the antrum but not inside any PV. At 402 ± 71 days of follow-up, the estimated freedom from arrhythmia was 89% in the Re-WACA group and 69% in the Re-PVI group (p = 0.01). Re-WACA independently predicted arrhythmia-free survival (HR = 0.39, 95% CI 0.16-0.93, p = 0.03), whereas two previous PVI procedures predicted recurrences (HR = 2.35, 95% CI 1.20-4.46, p = 0.01). The Re-WACA strategy guided by HDM significantly improved arrhythmia-free survival as compared to conventional ostial re-PVI. Residual PV antral potentials after prior PVI are frequent and can be easily visualized by HDM.

Case report: "A healthy woman with exertional dyspnea: Indication of a pacemaker or not?"

The selection of patients with chronotropic incompetence (CI) for cardiac pacing therapy remains challenging. Here, we present a case of a 40-year-old woman with severe exertional dyspnea. The exercise test revealed a blunted increase in the heart rate (HR) (maximum of 110 bpm). Her exercise capacity significantly improved under atrial stimulation at 170 bpm using a temporary pacing lead. Therefore, we implanted a rate-adaptive dual-chamber pacemaker with a blended sensor. During follow-up exercise capacity normalized, and she had no residual exertional dyspnea at 6 months. This case highlights the potential value for individual assessments of CI to identify clear indications for pacemaker implantation.

Radiofrequency Pulmonary Vein Isolation without Esophageal Temperature Monitoring: Contact-Force Characteristics and Incidence of Esophageal Thermal Damage.

Esophageal thermal lesions following pulmonary vein isolation (PVI) for atrial fibrillation (AF) potentially harbor lethal complications. Radiofrequency (RF)-PVI using contact force-technology can reduce collateral damage. We evaluated the incidence of endoscopically detected esophageal lesions (EDEL) and the contribution of contact force to esophageal lesion formation without esophageal temperature monitoring. One hundred and thirty-one AF patients underwent contact force-guided RF-PVI. Contact force, energy, force-time-integral, and force-power-time-integral were adopted. During PVI at the posterior segment of the wide antral circumferential line, limits were set for energy (30 W), duration (30 s) and contact force (40 g). Ablations were analyzed postero-superior and -inferior around PVs. Endoscopy within 120 h identified EDEL in six patients (4.6%). In EDEL(+), obesity was less frequent (17% vs. 68%, p = 0.018), creatinine was higher (1.55 ± 1.18 vs. 1.07 ± 0.42 mg/dL, p = 0.016), and exclusively at the left postero-inferior site, force-time-integral and force-power-time-integral were greater (2973 ± 3267 vs. 1757 ± 1262 g·s, p = 0.042 and 83,547 ± 105,940 vs. 43,556 ± 35,255 g·J, p = 0.022, respectively) as compared to EDEL(-) patients. No major complications occurred. At 12 months, arrhythmia-free survival was 74%. The incidence of EDEL was low after contact force-guided RF-PVI. Implementing combined contact force-indices on the postero-inferior site of left-sided PVs may reduce EDEL.

Clinical Impact of Circulating Galectin-3 on Ventricular Arrhythmias and Heart Failure Hospitalization Independent of Prior Ventricular Arrhythmic Events in Patients with Implantable Cardioverter-defibrillators.

Objective For risk stratification of sudden cardiac death in patients with structural heart disease, more precise predictors in addition to left ventricular ejection fraction (LVEF) are clinically needed. The present study assessed the utility of galectin-3 as an independent indicator for the prognosis of heart failure patients with implantable cardioverter-defibrillators (ICD). Methods The study population consisted of 91 consecutive patients who underwent a routine ICD checkup in our ICD outpatient clinic. Circulating galectin-3 was assessed using a commercially available enzyme-linked immunosorbent assay kit. The enrolled patients were prospectively followed. The primary endpoint was defined as the occurrence of appropriate ICD therapy (AIT), and the secondary endpoint was defined as the occurrence of unplanned overnight hospitalization due to decompensated heart failure (dHF). Results During a mean follow-up of 472±107 days, AIT occurred in 18 patients (20%). Unplanned hospitalizations due to dHF were noted in 12 patients (13%). A receiver-operative characteristics analysis demonstrated a sensitivity of 83% and specificity of 68% for AIT occurrences with a galectin-3 cut-off value of 13.1 ng/mL (area under the curve =0.82). A Kaplan-Meier analysis demonstrated that patients with galectin-3 >13.1 ng/mL had significantly higher incidences of AIT as compared to those with lower galectin-3 (log-rank, p<0.001). This significance was also observed in both subgroup analyses with ischemic and non-ischemic etiology. Cox regression demonstrated that higher galectin-3 was an independent predictor of AIT and dHF, even after adjusting for previous arrhythmic events. Conclusion The circulating galectin-3 level can be used as a clinical indicator of subsequent occurrence of ventricular arrhythmic events and decompensated heart failure, regardless of a history of ventricular arrhythmias.

Efficient screening for severe aortic valve stenosis using understandable artificial intelligence: a prospective diagnostic accuracy study.

Aims: The medical need for screening of aortic valve stenosis (AS), which leads to timely and appropriate medical intervention, is rapidly increasing because of the high prevalence of AS in elderly population. This study aimed to establish a screening method using understandable artificial intelligence (AI) to detect severe AS based on heart sounds and to package the built AI into a smartphone application. Methods and results: In this diagnostic accuracy study, we developed multiple convolutional neural networks (CNNs) using a modified stratified five-fold cross-validation to detect severe AS in electronic heart sound data recorded at three auscultation locations. Clinical validation was performed with the developed smartphone application in an independent cohort (model establishment: n = 556, clinical validation: n = 132). Our ensemble technique integrating the heart sounds from multiple auscultation locations increased the detection accuracy of CNN model by compensating detection errors. The established smartphone application achieved a sensitivity, specificity, accuracy, and F1 value of 97.6% (41/42), 94.4% (85/90), 95.7% (126/132), and 0.93, respectively, which were higher compared with the consensus of cardiologists (81.0%, 93.3%, 89.4%, and 0.829, respectively), implying a good utility for severe AS screening. The Gradient-based Class Activation Map demonstrated that the built AIs could focus on specific heart sounds to differentiate the severity of AS. Conclusions: Our CNN model combining multiple auscultation locations and exported on smartphone application could efficiently identify severe AS based on heart sounds. The visual explanation of AI decisions for heart sounds was interpretable. These technologies may support medical training and remote consultations.

Uninterrupted anticoagulation during catheter ablation for atrial fibrillation: no difference in major bleeding and stroke between direct oral anticoagulants and vitamin K antagonists in an updated meta-analysis of randomised controlled trials.

BACKGROUND: Periprocedural uninterrupted anticoagulation for catheter ablation of atrial fibrillation (AF) became standard after positive results of vitamin K antagonist (VKA) trials. Previous studies of uninterrupted direct oral anticoagulants (DOACs) vs. VKA have given controversial results. We thus aimed to elucidate the risk/benefit ratio of uninterrupted DOAC vs. VKA during catheter ablation of AF in an updated meta-analysis of randomised controlled trials (RCTs). METHODS: Online databases were searched for RCTs comparing uninterrupted DOAC to VKA in patients undergoing catheter ablation of AF. Data from retrieved studies were analysed in a comprehensive meta-analysis. Primary safety outcome was major bleeding; primary efficacy outcome was stroke or transient ischaemic attack (TIA). Secondary outcomes included a composite of major bleeding and stroke or TIA, minor bleeding, acute cerebral lesions on magnetic resonance imaging (MRI), and mortality. RESULTS: Six eligible RCTs comprising 2,369 patients were included. There were no significant differences in DOAC vs. VKA concerning the rates of major bleeding (2.2% vs. 3.8%; odds ratio (OR) 0.69, 95% confidence interval (CI) 0.30-1.56; p = .37) and stroke or TIA (0.2% vs. 0.2%; OR 0.97, CI 0.20-4.72; p = .97). Pooled meta-analysis of secondary outcomes revealed no significant differences (OR 0.73, p = .49 for composite of major bleeding and stroke or TIA; OR 1.08, p = .52 for minor bleeding; OR 1.12, p = .59 for acute cerebral lesions on MRI; and OR 0.60, p = .64 for all-cause mortality). CONCLUSION: Our meta-analysis suggests that uninterrupted DOAC is not superior to VKA in patients undergoing catheter ablation of AF with comparable rates of major bleeding and stroke.

One-Year Course of Periprocedural Anticoagulation in Atrial Fibrillation Ablation: Results of a German Nationwide Survey.

INTRODUCTION: Periprocedural oral anticoagulation (OAC) strategies for atrial fibrillation (AF) ablation procedures are changing rapidly. OBJECTIVE: To assess the management and course of periprocedural OAC for AF ablation procedures in experienced electrophysiology (EP) centers in Germany over the last 12 months. METHODS: The data are based on an electronic questionnaire, which was sent to 35 experienced EP centers in September 2018 and then exactly 1 year later. Participants provided information on their periprocedural OAC management, the handling with dual therapy (OAC plus single antiplatelet therapy), the availability of specific antidotes, the transseptal puncture approach, and noteworthy complications. RESULTS: Responses were received from all 35 centers and represent 10,010 AF ablation procedures annually. In 2018, the administration of vitamin K antagonist (VKA) was continued throughout the procedure at all centers (100%). In contrast, the majority of centers used minimally interrupted periprocedural non-vitamin K antagonist oral anticoagulants (NOAC) (54.3%), 13 centers (37.2%) completely interrupted NOAC, and only 3 centers (8.5%) continued NOAC throughout the procedure. At the 1-year follow-up survey, 32 centers were found to have continued their previous strategy of periprocedural OAC and 3 changed from a minimally interrupted to a continued NOAC strategy. Of note, 30 centers (85.7%) performed transseptal puncture fluoroscopically without additional cardiac imaging. In the setting of uninterrupted periprocedural OAC management, no relevant complications were noted. CONCLUSION: Our survey shows marked heterogeneous periprocedural OAC management at experienced EP centers in Germany. Whereas continuation of VKA has already been integrated into clinical practice, the majority of centers still use a minimally interrupted NOAC strategy.

Performance of a convolutional neural network derived from an ECG database in recognizing myocardial infarction.

Artificial intelligence (AI) is developing rapidly in the medical technology field, particularly in image analysis. ECG-diagnosis is an image analysis in the sense that cardiologists assess the waveforms presented in a 2-dimensional image. We hypothesized that an AI using a convolutional neural network (CNN) may also recognize ECG images and patterns accurately. We used the PTB ECG database consisting of 289 ECGs including 148 myocardial infarction (MI) cases to develop a CNN to recognize MI in ECG. Our CNN model, equipped with 6-layer architecture, was trained with training-set ECGs. After that, our CNN and 10 physicians are tested with test-set ECGs and compared their MI recognition capability in metrics F1 (harmonic mean of precision and recall) and accuracy. The F1 and accuracy by our CNN were significantly higher (83 ± 4%, 81 ± 4%) as compared to physicians (70 ± 7%, 67 ± 7%, P < 0.0001, respectively). Furthermore, elimination of Goldberger-leads or ECG image compression up to quarter resolution did not significantly decrease the recognition capability. Deep learning with a simple CNN for image analysis may achieve a comparable capability to physicians in recognizing MI on ECG. Further investigation is warranted for the use of AI in ECG image assessment.

Clinical significance of precedent asymptomatic non-sustained ventricular tachycardias on subsequent ICD interventions and heart failure hospitalization in primary prevention ICD patients.

BACKGROUND: The prognostic implications of non-sustained ventricular tachycardia (NSVT) and their significance as therapeutic targets in patients without prior sustained ventricular arrhythmias remain undetermined. The aim of this study was to investigate the prognostic significance of asymptomatic NSVT in patients who had primary prevention implantable cardioverter-defibrillator (ICD) implantation due to ischemic or non-ischemic cardiomyopathy (ICM, NICM). METHODS: We enrolled 157 consecutive primary prevention ICD patients without previous appropriate ICD therapy (AIT). Patients were allocated to two groups depending on the presence or absence of NSVT in a 6-month period prior to enrollment. The incidence of AIT and unplanned hospitalization due to decompensated heart failure (HF) were assessed during follow-up. RESULTS: In 51 patients (32%), precedent NSVT was documented. During a median follow-up of 1011 days, AIT occurred in 36 patients (23%) and unplanned HF hospitalization was observed in 32 patients (20%). In precedent NSVT patients, the incidence of AIT and unplanned HF hospitalization was significantly higher as compared to patients without precedent NSVT (AIT: 29/51 [57%] vs. 7/106 [7%], P < 0.001, log-rank; HF hospitalization: 16/51 [31%] vs. 16/106 [15%], P = 0.043, log-rank). Cox-regression demonstrated that precedent NSVT independently predicted AIT (P < 0.0001). In subgroup analyses, precedent NSVT predicted AIT in both ICM and NICM (P < 0.0001, P = 0.020), but predicted HF hospitalization only in patients with ICM (P = 0.0030). CONCLUSIONS: Precedent non-sustained VT in patients with primary prevention ICDs is associated with subsequent appropriate ICD therapies, and is an independent predictor of unplanned heart failure hospitalizations in patients with ischemic cardiomyopathy.

Usefulness of Serum Free Thyroxine Concentration to Predict Ventricular Arrhythmia Risk in Euthyroid Patients With Structural Heart Disease.

The aim of the present study was to determine whether free thyroxine (FT4) and calculated thyroid parameters predict the incidence of ventricular arrhythmias in euthyroid heart failure patients with implantable cardioverter-defibrillators (ICD). In this open-label prospective cohort study, 115 consecutive euthyroid patients (mean age 62.9 ± 1.3 years; 87% male; ischemic cardiomyopathy 63%) scheduled for primary prevention ICD implantation or exchange were enrolled. Serum concentrations of thyrotropin (thyroid-stimulating hormone) and FT4 were measured 1 day before device operation. Primary and secondary end points were defined as occurrence of appropriate ICD therapy (AIT) and cardiovascular death, respectively. During a mean follow-up of 1,191 ± 35 days, 24 patients (21%) experienced AIT, and cardiovascular death was observed in 10 patients (9%). Patients with AIT had higher FT4 concentrations compared with those without AIT (18.9 ± 0.48 vs 16.2 ± 0.22 pmol/L, p <0.001). FT4 was an independent predictor of AIT in an adjusted Cox regression (hazard ratio = 1.47, p <0.001). Kaplan-Meier analysis demonstrated that Jostel's thyroid-stimulating hormone index, reflecting the central component of the hypothalamus-pituitary-thyroid loop, and SPINA-GT as surrogate markers for thyroid's secretory capacity predicted AIT incidences. None of the indices predicted cardiovascular death. In conclusion, FT4 concentration predicts an increased incidence of ventricular arrhythmias in euthyroid patients receiving ICDs for primary prevention. Our data suggest that both impending primary hyperthyroidism and an increased thyroid homeostasis set point may increase the rate of AIT in this patient population.

Avoiding inappropriate therapy of single-lead implantable cardioverter-defibrillator by using atrial-sensing electrodes.

INTRODUCTION: The single-chamber implantable cardioverter-defibrillator (ICD) can be associated with more frequent inappropriate therapies compared with dual-chamber ICDs, when they are accompanied by a simpler implantation procedure. The aim of this study was to investigate whether the use of a single-lead ICD system with atrial-sensing electrodes results in a reduction of inappropriate ICD therapy. METHODS AND RESULTS: The study population consisted of 212 consecutive patients, who underwent primary prophylactic single-lead ICD implantation at our institute. A ventricular lead with atrial-sensing electrodes was implanted in 77 patients (36%; Group-VDD) and a ventricular lead without atrial-sensing electrodes was implanted in 135 patients (64%; Group-VVI). Procedural and follow-up data were collected in a prospective registry. A higher prevalence of atrial fibrillation was present in Group-VDD. There were no other significant differences in patient baseline characteristics (age, sex, and other comorbidities) or follow-up period between the two groups. The operative parameters including fluoroscopic burden showed no significant differences between Group-VDD and Group-VVI. During a mean follow-up period of 697 ± 392 days, 26 patients (12%) experienced appropriate ICD therapies and 13 patients (6%) suffered inappropriate ICD therapies. The incidence of inappropriate ICD therapies in Group-VDD was significantly lower as compared to that of Group-VVI (1/77 [1%] vs 12/135 [9%]; log-rank, P = 0.028). The incidence of appropriate ICD therapies and the occurrence of device-related complications showed no significant difference between the two groups. CONCLUSION: Single-lead ICD with atrial-sensing electrodes shows a lower incidence of inappropriate ICD therapy compared with the absence of atrial-sensing electrodes, without additional operative burden or increased complications.