Search Results (41)

This technical report presents a compelling case for the use of very-high-power, very-short-duration (VHPSD) radiofrequency ablation as a promising and efficient strategy for treating symptomatic premature ventricular contractions (PVCs) originating from the right ventricular outflow tract (RVOT). The patient with frequent, symptomatic PVCs and a 24% burden underwent successful ablation using a 90 W/4 s recipe via the QDOT MICRO™ catheter. The procedure resulted in immediate and sustained elimination of PVCs, with only 4 s of ablation time, near-zero fluoroscopy, no complications, and no PVC recurrence at 6 months. VHPSD ablation, though originally developed for atrial fibrillation, demonstrated remarkable procedural efficiency, precision, and lesion efficacy in this case. Compared to standard power, long-duration (SPLD) ablation, VHPSD offers the potential to significantly reduce procedural time, minimize tissue edema, and lower complication risk, particularly advantageous in anatomically challenging areas or in situations where maintaining stable catheter contact for extended periods is difficult or unfeasible. This technical report suggests the transformative potential of VHPSD as a first-line ablation strategy for RVOT-PVCs, provided careful mapping and appropriate technique are used. It underscores the need for further prospective studies to validate its broader safety, efficacy, and role in PVC management, particularly in cases involving intramural origins. Full article

Background: Hypertrophic cardiomyopathy (HCM) is a genetic cardiomyopathy marked by increased left ventricular wall thickness, leading in some cases to left ventricular outflow tract (LVOT) obstruction, heart failure, and arrhythmias. Mavacamten, a selective allosteric inhibitor of cardiac myosin, has demonstrated benefits in improving hemodynamics and reducing LVOT obstruction. However, its impact on arrhythmic burden remains unclear, with reports of early atrial fibrillation (AF) risk contrasting with long-term reductions in arrhythmias. This study assesses the temporal patterns of Holter-detected arrhythmias in HCM patients treated with mavacamten. Methods: This retrospective study included HCM patients from three Mayo Clinic sites. Baseline demographic, clinical, and echocardiographic data were collected. Holter monitoring was performed at baseline, short-term (<6 months), and long-term (>6 months) follow-up. Arrhythmic events, including premature atrial contractions (PACs), premature ventricular contractions (PVCs), and supraventricular tachycardia (SVT), were analyzed using standardized rates per 24 h. Statistical comparisons utilized the Wilcoxon signed-rank test. Results: Twenty-seven patients (56% female, median age 66 years) were included. PACs, PVCs, and SVT duration transiently but not significantly increased at short-term follow-up but returned to baseline at long-term follow-up. No sustained or high-risk ventricular arrhythmias were observed. Conclusions: Mavacamten is associated with transient arrhythmic fluctuations early in treatment, followed by stabilization. These findings support its long-term electrophysiological safety and underscore the need for early rhythm monitoring. Further research should explore its role in arrhythmic risk stratification in HCM patients. Full article

Cardiac troponin-I (cTnI) is a highly sensitive and specific marker of myocardial injury detectable in plasma by immunoassay techniques. Inclusion criteria over a 3-year period required a diagnosis of cardiac disease accompanied by electrocardiographic (ECG) and cardiac ultrasound examinations (n = 23) in adult horses (≥2 years of age). A second group of normal adult ponies (n = 12) was studied as a reference group. Heparinized jugular venous blood samples were collected and centrifuged within 30 min, and the plasma was separated and frozen at −70 °C for subsequent batched cTnI analysis. The lower limit of detection was 0.01 ng/mL, and the upper limit was 100 ng/mL of plasma. Normal equine plasma cTnI concentrations ranged from 0.01 to 0.03 ng/mL (n = 12). Horses with non-arrhythmogenic murmurs (n = 4) included tricuspid (0.05 ng/mL cTnI), mitral (0.07), and aortic insufficiencies (0.01, 0.02). Horses with benign atrial fibrillation (n = 8) had a cTnI range of <0.01–0.09 ng/mL, with four horses having cTnI concentrations falling slightly outside the reference range (0.04, 0.05, 0.06, and 0.09). Horses with ventricular arrhythmias (ventricular premature contractions or ventricular tachycardia) and documentable myocardial toxicities or immunological reactions (n = 5) had cTnI concentrations of 0.05, 0.21, 0.31, 15.18, and >100 ng/mL. Horses with ventricular arrhythmias but no documentation of myocardial toxicity (n = 3) had cTnI concentrations of 0.34, 0.46, and 80.42 ng/mL. When grouped by arrhythmia type and compared using the Mann–Whitney Rank Sum Test, the median ventricular arrhythmia cTnI (0.40 ng/mL) was significantly higher than the median atrial fibrillation cTnI (0.04 ng/mL, p < 0.001). It was concluded that horses with myocardial toxicities and ventricular arrhythmias often had severe elevations in plasma cTnI. Full article

Background: The safety and efficacy of electrophysiological (EP) procedures using ultrasound (US) guidance are being increasingly studied. We investigated if a systematic workflow with ultrasound guidance (the US4ABL), comprising four steps (transesophageal echocardiography (TEE) for left atrial thrombus exclusion, US of the groin vessels to guide femoral access, TEE-aided transseptal puncture, and transthoracic echocardiography (TTE) for exclusion of pericardial tamponade after the procedure), reduces the number of complications and fluoroscopy duration and dose. Methods: A total of 212 consecutive patients underwent left-sided ablations using the US4ABL workflow and were compared to a group of 299 patients who underwent the same type of ablations using post-procedural TTE to exclude tamponade (standard group: venous and/or arterial access by palpation and fluoroscopy, and pressure guided transseptal puncture). Complications, procedural duration, fluoroscopy duration, and dose were compared. Results: The cohort included 511 patients (42% female); 43.8% of patients suffered from paroxysmal atrial fibrillation (AF), 35.4% presented with persistent AF, 10.7% underwent the procedure was for atrial tachycardia, and 10% of patients had premature ventricular contractions. The complication rate in the US4ABL group was lower compared to the standard group: 0 complications vs. 11 complications (3.7%, mainly vascular and pericardial), respectively (p = 0.005). The procedure times were lower in the US4ABL group (p < 0.01), whereas the fluoroscopy time and dose did not differ significantly. Conclusions: A fully ultrasound-guided (US4ABL) workflow for left atrial and ventricular electrophysiology procedures reduces the complication rate and the procedure time. Full article

Background: The wearable cardioverter defibrillator (WCD) has emerged as a valuable tool used for temporary protection from sudden cardiac death. However, since the WCD uses surface electrodes to detect arrhythmias, it is susceptible to inappropriate detection. Although shock conversion rates for the WCD are reported to be high for detected events, its efficacy in clinical practice tends to be degraded by patient noncompliance. Reasons for this include wearer discomfort and frequent false alarms, which may interrupt sleep and generate anxiety. Up to now, data on the incidence of false alarms emitted by the WCD and their predictors are rare. Objectives: The aim of our study was to assess the relationship between both artifact sensing and episode misclassification burden and wearing compliance in patients with a WCD (ZOLL LifeVest™ 4000 system, ZOLL CMS GmbH, Cologne, Germany). Methods and Results: We conducted a single-center retrospective observational study, analyzing patients with a WCD prescribed at our institution. A total of 134 patients (mean age 51.7 ± 13.8 years, 79.1% male) were included. Arrhythmia recordings were analyzed and categorized as non-sustained ventricular tachycardia, sustained ventricular tachycardia or fibrillation, artifact sensing or misclassified episodes. Indication for WCD prescription was both primary and secondary prophylaxis. A total of 3019 false WCD alarms were documented in 78 patients (average number of false alarms 38.7 ± 169.5 episodes per patient) over a mean WCD wearing time of 71.5 ± 70.9 days (daily WCD wearing time 20.2 ± 5.0 h). In a total of 78 patients (58.2% of the study population), either artifact sensing (76.9%), misclassified episodes (6.4%), or both (16.7%) occurred. Misclassified episodes included sinus tachycardias, atrial flutter, atrial fibrillation, premature ventricular contractions (PVCs), and intermittent bundle branch block. A multiple linear regression identified loop diuretics (regression coefficient [B] −0.11; 95% CI −0.21–(−0.0001); p = 0.049), angiotensin receptor–neprilysin inhibitors (ARNIs) (B −0.11; 95% CI 0.22–(−0.01); p = 0.033), and a higher R-amplitude of the WCD baseline electrocardiogram (ECG) (B −0.17; 95% CI −0.27–(−0.07); p = 0.001) as independent predictors for a lower number of artifact episodes per day. In addition, atrial fibrillation (B 0.05; 95% CI 0.01–0.08; p = 0.010), and calcium antagonists (B 0.07; 95% CI 0.02–0.12; p = 0.012) were independent predictors for increased numbers of misclassified episodes per day, while beta-blockers seemed to reduce them (B −0.06; 95% CI −0.10–(−0.01); p = 0.013). Patients terminated 61.0% of all false alarms manually by pressing the response button on average 1.9 times per false alarm with overall 3.6 manual terminations per affected patient per month. Conclusions: In conclusion, false alarms from the ZOLL LifeVest™ system were frequent, with artifact sensing being the most common cause. Hence, the occurrence of false alarms represents a significant side effect of WCD therapy, and efforts should be made to minimize false alarms. Full article

Echocardiography is recommended as a first-line diagnostic tool in patients with premature ventricular contractions (PVCs). However, standard echocardiography is not always able to identify early signs of myocardial dysfunction and cardiac magnetic resonance (CMR) may offer additional information. Since CMR has lower accessibility and higher cost compared to echocardiography, we wanted to evaluate how additional echocardiographic parameters, not included in routine examinations, perform compared to CMR in detecting signs of cardiomyopathy in PVC patients with normal findings at a standard echocardiogram. We compared CMR findings and results from an extended echocardiographic examination in thirty-nine patients who had a high PVC burden. The additional echocardiographic parameters were global longitudinal strain, mechanical dispersion, ventricular–arterial coupling, integrated backscatter and left atrial activation time. Eleven patients had pathological findings at CMR. The additional echocardiographic parameters did not significantly differ between patients with or without CMR findings. However, several patients with normal CMR findings showed signs of ventricular dysfunction when evaluated with the additional echocardiographic parameters, which suggests that these could possibly offer supplementary information in the assessment of PVC patients. Full article

Arrhythmias are among the most prevalent cardiac conditions and frequently serve as a direct cause of sudden cardiac death. Hence, the automated detection of arrhythmias holds significant importance for assisting in the diagnosis of heart conditions. Recently, the photoplethysmography (PPG) signal, capable of conveying heartbeat information, has found application in the field of arrhythmia detection research. This work proposes a hybrid deep learning model, Res-BiANet, designed for the detection and classification of multiple types of arrhythmias. The improved ResNet and BiLSTM models are connected in parallel, and spatial and temporal features of PPG signals are extracted using ResNet and BiLSTM, respectively. Subsequent to BiLSTM, a multi-head self-attention mechanism was incorporated to enhance the extraction of global temporal correlation features over long distances. The model classifies five types of arrhythmia rhythms (premature ventricular contractions, premature atrial contractions, ventricular tachycardia, supraventricular tachycardia, and atrial fibrillation) and normal rhythm (sinus rhythm). Based on this foundation, experiments were conducted utilizing publicly accessible datasets, encompassing a total of 46,827 PPG signal fragments from 91 patients with arrhythmias. The experimental results demonstrate that Res-BiANet achieved exceptional classification performance, including an F1 score of 86.88%, overall accuracy of 92.38%, and precision, sensitivity, and specificity of 88.46%, 85.15%, and 98.43%, respectively. The outstanding performance of the Res-BiANet model suggests significant potential in supporting the auxiliary diagnosis of multiple types of arrhythmias. Full article

Background: Cardiovascular diseases and arrhythmias are medical conditions that increase with age and are associated with significant morbidities and mortality. The aim of the present study was to investigate the prevalence of arrhythmias and clinical associations in the collective of older adults receiving comprehensive geriatric care (CGC). Methods: Holter ECG monitoring (HECG) of older patients hospitalized for CGC was analyzed. The prevalence of arrhythmias and the associations between the presence of arrhythmias, patients’ characteristics and the functional status regarding basic activities of daily living (assessed by the Barthel index (BI)), walking ability (assessed by the timed up and go test (TUG)), and balance and gait (assessed by the Tinetti balance and gait test (TBGT)) were examined. Results: In the presented study, 626 patients were included (mean age: 83.9 ± 6.6 years, 67.7% were female). The most common arrhythmias detected in HECG were premature ventricular contractions (87.2%), premature atrial contractions (71.7%), and atrial fibrillation (22.7%). Atrial flutter was found in 1.0%, paroxysmal supraventricular tachycardia in 5.8%, non-sustained ventricular tachycardia in 12.5%, first-degree AV block in 0.8%, second-degree AV block type Mobitz I in 0.8%, second-degree AV block type Mobitz II in 0.3%, pause > 2.5 s any cause in 3.5%, and pause > 3 s any cause in 1.6% of the cases. Premature atrial contractions were associated with the female sex (74.8% vs. 65.3%, p = 0.018), whereas in male patients, the following arrhythmias were more common: premature ventricular contractions (91.6% vs. 85.1%, p = 0.029), ventricular bigeminus (8.4% vs. 3.8%, p = 0.021), and non-sustained ventricular tachycardia (17.3% vs. 10.1%, p = 0.014). Atrial fibrillation detected in HECG was more frequent in patients at high risk of falls, indicated by their TBGT score ≤ 18 (24.7% vs. 12.0%, p = 0.006), and premature ventricular contractions were more common in patients unable to walk (TUG score 5) compared to those with largely independent mobility (TUG score 1 or 2) (88.0% vs. 75.0%, p = 0.023). In a logistic regression analysis, atrial fibrillation detected in HECG was identified as a risk factor for a high risk of falls (odds ratio (OR): 2.35, 95% confidence interval (CI): 1.23–4.46). Conclusion: In our study, investigation of HECG of older adults hospitalized for CGC revealed that premature atrial contractions, premature ventricular contractions, and atrial fibrillation were the most common arrhythmias. Premature atrial contractions were found to be more frequent in female patients, while male patients were more prone to premature ventricular contractions. In the investigated population, atrial fibrillation emerged as a risk factor associated with a high risk of falls. Full article

Aims—Electrocardiography (ECG) and echocardiographic left atrial (LA) parameters may be helpful to assess the risk of atrial fibrillation (AF) in embolic stroke of unknown etiology (ESUS) and could therefore guide intensity of ECG monitoring. Methods—1153 consecutive patients with ischemic stroke or transient ischemic attack (TIA) were analyzed. An internal loop recorder (ILR) was implanted in 104 consecutive patients with ESUS. Multiple morphologic P-wave parameters in baseline 12-channel ECG and echocardiographic LA parameters were measured and analyzed in patients with and without ILR-detected AF. Using logistic regression, we evaluated the predictive value of several ECG parameters and LA dimensions on the occurrence of AF. Results—In 20 of 104 (19%) patients, AF was diagnosed by ILR during a mean monitoring time of 575 (IQR 470–580) days. Patients with AF were significantly older (72 (67–75) vs. 60 (52–72) years; p = 0.001) and premature atrial contractions (PAC) were more frequently observed (40% vs. 2%; p < 0.001) during baseline ECG. All morphologic P-wave parameters did not show a significant difference between groups. There was a non-significant trend towards a larger LA volume index (31 (24–36) vs. 29 (25–37) mL/m²; p = 0.09) in AF patients. Conclusions—Age and PAC are independently associated with incident AF in ESUS and could be used as markers for selecting patients that may benefit from more extensive rhythm monitoring or ILR implantation. In our consecutive cohort of patients with ESUS, neither morphological P-wave parameters nor LA size were predictive of AF. Full article

This study aims to compare the effectiveness of using discrete heartbeats versus an entire 12-lead electrocardiogram (ECG) as the input for predicting future occurrences of arrhythmia and atrial fibrillation using deep learning models. Experiments were conducted using two types of inputs: a combination of discrete heartbeats extracted from 12-lead ECG and an entire 12-lead ECG signal of 10 s. This study utilized 326,904 ECG signals from 134,447 patients and categorized them into three groups: true–normal sinus rhythm (T-NSR), atrial fibrillation–normal sinus rhythm (AF-NSR), and clinically important arrhythmia–normal sinus rhythm (CIA-NSR). The T-NSR group comprised patients with at least three normal rhythms in a year and no atrial fibrillation or arrhythmias history. Clinically important arrhythmia included atrial fibrillation, atrial flutter, atrial premature contraction, atrial tachycardia, ventricular premature contraction, ventricular tachycardia, right and left bundle branch block, and atrioventricular block over the second degree. The AF-NSR group included normal sinus rhythm paired with atrial fibrillation or atrial flutter within 14 days, and the CIA-NSR group comprised normal sinus rhythm paired with CIA occurring within 14 days. Three deep learning models, ResNet-18, LSTM, and Transformer-based models, were utilized to distinguish T-NSR from AF-NSR and T-NSR from CIA-NSR. The experiments demonstrated the potential of using discrete heartbeats in predicting future arrhythmia and atrial fibrillation incidences extracted from 12-lead electrocardiogram (ECG) signals alone, without any additional patient information. The analysis reveals that these discrete heartbeats contain subtle patterns that deep learning models can identify. Focusing on discrete heartbeats may lead to more timely and accurate diagnoses of these conditions, improving patient outcomes and enabling automated diagnosis using ECG signals as a biomarker. Full article

Background: Oral beta-blockers are effective for heart failure and hypertension. Here, we conducted a prospective study to investigate the efficacy of the beta-blocker bisoprolol in patients switching from the oral tablet to the transdermal patch. Methods: We studied 50 outpatients receiving oral bisoprolol for chronic heart failure and hypertension. After patients switched treatments, we measured heart rate (HR) over 24 h by Holter echocardiography as the primary endpoint. Secondary endpoints were (1) HR at 00:00, 06:00, 12:00, and 18:00, (2) the total number of premature atrial contractions (PACs) over 24 h and the incidence rate per time segment, and the total number of premature ventricular contractions (PVCs) over 24 h and the incidence rate per time segment, (3) blood pressure, (4) atrial natriuretic peptide and B-type natriuretic peptide, and (5) echocardiography. Results: Minimum, maximum, mean, and total HR over 24 h was not significantly different between the two groups. Mean and maximum HR at 06:00, total PACs, total PVCs, and PVCs at 00:00 to 05:59 and 06:00 to 11:59 were significantly lower in the patch group. Conclusion: Compared with oral bisoprolol, the bisoprolol transdermal patch lowers HR at 06:00 and inhibits the onset of PVCs during sleep and in the morning. Full article

Pulsed field ablation (PFA) is a new ablative method for the therapy of arrhythmia. Recent preclinical and clinical studies have already demonstrated the feasibility and safety of PFA for the treatment of atrial fibrillation (AF). However, the application of PFA may not be limited to the above fields. There are some data on the application of PFA on ventricular arrhythmias (VAs), such as ventricular fibrillation (VF) and ventricular tachycardia (VT). Further, a case report about PFA has been published recently, in which PFA was successfully applied to the ablation of premature ventricular contractions (PVCs) from the right ventricular outflow tract. Thus, we aimed to review recent research findings of PFA in ventricular ablation and evaluate the possibility of its application in VAs. Full article

An electrocardiogram (ECG) is used to check the electrical activity of the heart over a limited short-term or long-term period. Short-term observations are often used in hospitals or clinics, whereas long-term observations (often called continuous or stream-like ECG observations) are used to monitor the heart’s electrical activity on a daily basis and during different daily activities, such as sleeping, running, eating, etc. ECG can reflect the normal sinus rhythm as well as different heart problems, which might vary from Premature Atrial Contractions (PAC) and Premature Ventricular Contractions (PVC), to Sinus Arrest and many other problems. In order to perform such monitoring on a daily basis, it is very important to implement automated solutions that perform most of the work of the daily ECG analysis and could alert the doctors in case of any problem, and could even detect the type of the problem in order for the doctors to have an immediate report about the patient’s health status. This paper aims to provide a workflow for abnormal ECG signals detection from different sources of digitized ECG signals, including ambulatory devices. We propose an algorithm for ECG pre-annotation and beat-to-beat separation for heartbeat classification using Autoencoders. The algorithm includes the training of different models for different types of abnormal ECG signals, and has shown promising results for normal sinus rhythm and PVC compared to other solutions. This solution is proposed for no-noise and noisy signals as well. Full article

Aims/Objectives: Patients with bleeding disorders are a rare and complex population in catheter ablation (CA) procedures. The most common types of bleeding disorders are von Willebrand disease (VWD) and hemophilia A (HA). Patients with VWD or HA tend to have a higher risk of bleeding complications compared to other patients. There is a lack of data concerning peri- and postinterventional coagulation treatment. We sought to assess the optimal management of patients with VWD and HA referred for catheter ablation procedures. Methods and Results: In this study, we analyzed patients with VWD or HA undergoing CA procedures at two centers in Germany and Switzerland between 2016 and 2021. Clotting factors were administered in conjunction with hemostaseological recommendations. CA was performed as per the institutional standard. During the procedure, unfractionated heparin (UFH) was given intravenously with respect to the activated clotting time (ACT). Primary endpoints included the feasibility of the procedure, bleeding complications, and thromboembolic events during the procedure. Secondary endpoints included bleeding complications and thromboembolic events up to one year after catheter ablation. A total of seven patients (three VWD Type I, one VWD Type IIa, three HA) underwent 10 catheter ablation procedures (pulmonary vein isolation (PVI): two × radiofrequency (RF), one × laser balloon (LB), one × cryoballoon (CB); PVI + cavotricuspid isthmus (CTI): one × RF; PVI + left atrial appendage isolation (LAAI): one × RF; Premature ventricular contraction (PVC): three × RF; Atrioventricular nodal reentrant tachycardia (AVNRT): one × RF). VWD patients received 2000–3000 IE Wilate i.v. 30 to 45 min prior to ablation. Patients with HA received 2000–3000 IE factor VIII before the procedure. All patients undergoing PVI received UFH (cumulative dose 9000–18,000 IE) with a target ACT of >300 s. All patients after PVI were started on oral anticoagulation (OAC) 12 h after ablation. Two patients received aspirin (acetylsalicylic acid; ASA) for 4 weeks after the ablation of left-sided PVCs. No anticoagulation was prescribed after slow pathway modulation in a case with AVNRT. No bleeding complications or thromboembolic events were reported. During a follow-up of one year, one case of gastrointestinal bleeding occurred following OAC withdrawal after LAA occlusion. Conclusions: After the substitution of clotting factors, catheter ablation in patients with VWD and HA seems to be safe and feasible. Full article

Systemic sclerosis (SSc) is an autoimmune disease characterized by skin and internal organ fibrosis and microvascular impairment, which can affect major organs, including the heart. Arrhythmias are responsible for approximately 6% of deaths in patients with SSc, and mainly occur due to myocardial fibrosis, which causes electrical inhomogeneity. The aim of this study was to determine the frequency of arrhythmias and conduction disturbances in SSc cohorts, and to identify the characteristics and risk factors associated with the occurrence of dysrhythmias in patients with SSc. A systematic literature review using PubMed, Embase, Web of Science and Scopus databases was performed. Full-text articles in English with arrhythmias as the main topic published until 21 April 2022 were included. Most prevalent arrhythmias were premature supraventricular and ventricular contractions, while the most frequent conduction disturbance was represented by right bundle branch block (RBBB). Elevated concentrations of N-terminal prohormones of brain natriuretic peptides (NT-pro BNP) were associated with numerous types of atrial and ventricular arrhythmias, and with the occurrence of RBBB. A lower value of the turbulence slope (TS) emerged as an independent predictor for ventricular arrhythmias. In conclusion, dysrhythmias are frequent in SSc cohorts. Paraclinical and laboratory parameters are useful instruments that could lead to early diagnosis in the course of the disease. Full article