Premature Contractions Research Articles

Arrhythmia during gestation: from diagnosis to follow-up

Abstract Background Although arrhythmia is common cardiac complication during gestation, data on perinatal and neonatal outcomes in pregnant women with different arrhythmia management is limited. Purpose To explore clinical characteristics and outcomes of different management strategies in pregnant women with arrhythmias. Methods In this single-center, prospectively study we consequently included 87 cases of arrhythmias in pregnant (mean age 26.7±3.5 years, mean gestation age 24.6 ±3.3 weeks). Clinical characteristics, obstetric and neonatal outcomes were compared due to different arrhythmia management strategies: dynamic observation (the 1st group), antiarrhythmic therapy (the 2nd group) and catheter ablation (the 3rd group) within 12 month follow-up. Results Supraventricular tachycardia (n=47; 54%) was the most common arrhythmia in pregnant. Premature contraction was detected in 34 cases (39%). Cases of ventricular tachycardia (n=6; 7%) was rare during gestation. Benign course of arrhythmia was in 15 cases (17.2%) and do not require drug therapy or intervention. Antiarrhythmic drug was used for symptomatic patients with haemodynamic instability (n=28, 32.2%). Catheter ablation performed in cases of drug refractory and severe arrhythmias (n=44, 50.5%). The procedure performed under the guidance of CARTO (n=21; 47.7%) and Ensite Precision systems (n=23; 52.3%) without fluoroscopy and were successful in all cases (100%). The further course of gestation characterized by occurring increased incidence of uterine contractile activity (n=2, 4.5%, p=0.464) and placental abruption (n=2, 4.5%, p=0.464) only after catheter ablation while other complications were in all groups: uterine blood flow violation (n=6, 40% vs. n=4, 14.3% vs. n=6, 13.6%, p=0.168) and preeclampsia (n=1, 6.7% vs. n=1, 3.6% vs. n=2, 4.5%, p=0.730). Obstetric outcomes characterized by prevalence of vaginal delivery in all groups (n=13, 86.7% vs. n=22, 78.6% vs. n=37, 84%, p=0.465). Neonatal outcomes characterized by normal range of fetal birth weight and 5 minute Apgar score in all groups (3140.7±321.2 vs. 3265,3±290,1 vs. 3312,3±209,8 grams, p=0.701 and 8,6±1,1 vs. 8,5±1,2 vs. 8,6±1,2, p=0.721 respectively). There was no incidence of maternal and fetal mortality and arrhythmia recurrence after ablation in follow-up. Conclusions Supraventricular tachycardia is common in pregnancy. Arrhythmias in pregnant characterized by benign gestation course and outcomes regardless different management.

Ablation of premature ventricle contraction arising from papillary muscle without intracardiac echo using point-by-point mapping

Abstract Background Catheter radiofrequency ablation (RFA) of ventricular arrhythmias (VAs) arising from the left ventricle's papillary muscles (PM) has been associated with inconsistent results due to difficulties in 3D reconstruction of this intraventricular structure. The use of intracardiac echo-guided ablation allows for the 2D visualisation of the PM and the guiding of ablation catheter. Cryo energy allows stable contact with the target structure during ablation. These two techniques have been shown to increase the success rate of ablation (77% reported - 1) but don’t allow the construction of the 3D map of papillary muscle with activation during PVC. Using a combination of point-by-point mapping (PbP) along with "fast anatomical mapping" (FAM) (Carto® 3 System) allows 3D reconstruction of the PM geometry with activation. These may increase the accuracy of PVC origin targeting. Aim This study aims to assess the feasibility and success rate of RFA of PVC arising from the papillary muscles of the left ventricle. Methods and results We retrospectively analysed 214 patients treated with RFA for PVCs in two institutions. PVC arose from PM in 12(5.6%) cases (65±20 years old; 42% males; 33% with ejection fraction>50%; 8.3% antero-lateral PM). Initial detailed FAM of the left ventricle was performed using PVC pattern matching via transaortic or transmitral approach. Then, all points with preexcitation to QRS onset were copied from FAM into the new PbP map. That automatically created the geometry of PM with an activation map inside the LV shell. Irrigated high power (50 W) RFA was performed at the site of earliest activation at the PM shell. The acute success rate was 75% (n=9) without complications. PVC recurrence at 12-month follow-up was 11% (n=1 out of 9). Conclusions RFA of PVC arising from papillary muscles using point-by-point mapping is feasible and associated with a success rate comparable to the previously reported one when intracardiac echo-guided ablation is used.

Charge-density mapping to evaluate non-pulmonary vein substrate in patients with paroxysmal atrial fibrillation: the ACUPRED study

Abstract Background/introduction Pulmonary veins (PV) electrical isolation (PVI) is the main ablation strategy for the treatment of paroxysmal atrial fibrillation (AF), since the description of PV triggers. However, non-PV substrate and triggers in AF are not a negligible clinical issue. Indeed, in up to 22% of patients with AF recurrence after PVI, all PV are found isolated. Non-PV triggers can be demonstrated in up to 10-15% of non-selected patients at first AF ablation and non-PV substrate has been related to functional slow conduction and fibrosis also in paroxysmal AF. Purpose The aim of this study is to evaluate non-PV substrate (slow conduction) and triggers with charge-density (CD) mapping in patients with paroxysmal AF. Methods All patients, were prospectively enrolled in 2023. Inclusion criteria for the study were: 1) paroxysmal AF patients undergoing PVI procedure with a single-shot device and 2) CD mapping pre- and post- PVI. CD mapping was performed during CS proximal pacing at cycle length (CL) 600 ms and CS proximal pacing at CL 300 ms, pre- and post- PVI. Conduction velocity (CV) magnitude (in cm/s) and vector (direction and sense) were calculated offline for each CD map for all anatomical vertices. Reduction map was defined as the map of CV magnitude difference between CL 600 ms and CL 300 ms, Figure 1. Refraction map was defined as the map of CV direction difference between CL 600 ms and CL 300 ms, Figure 1. Non-PV substrate was defined at pre-PVI maps as: 1) slow conduction (<30 cm/s) at CL 600 ms or CL 300 ms, or 2) difference in CV magnitude (>25 cm/s) at reduction map, a marker of functional slow conduction (induced by fast pacing), or 3) difference in CV direction more than 90° between two neighboring vertices at refraction map, a marker of anisotropy, Figure 1. Non-PV triggers were defined as non-PV premature atrial contractions >10/min or inducing AF. Results A total of 43 patients (60.6 ± 11.2 years, 74.4% males) with paroxysmal AF undergoing first procedure PVI were analyzed. Non-PV substrate was found in 13 patients (30.2%). Non-PV triggers were found in 3 patients (6.9%), including one patient on the posterior wall near right PV antra and two patients on the posterior wall near the left PV antra. At a mean follow-up of 5.6 months, a total of 5 patients (11.6%) experienced a recurrence. Patients experiencing a recurrence had more frequently non-PV substrate (80.0% vs 23.7%, p=0.024) and lower CV magnitude at CL 600 ms pre-PVI (72.3 cm/s vs 83.1 cm/s, p=0.04). At survival analysis for 34 patients (79.1%) out of the 2 months blanking period, patients with non-PV substrate had lower freedom from AF recurrence (56% vs 90%, p=0.0028), Figure 2. Conclusion In patients with paroxysmal AF undergoing index PVI, non-PV substrate or triggers can be found in up to 37.1% of cases. Non-PV substrate is associated with worse arrhythmic prognosis.Figure 1Figure 2

Spontaneous atrial fibrillation occurrence following transesophageal atrial burst pacing in rats

Abstract Purpose Animal models play a crucial role in elucidating the complex pathophysiology of atrial fibrillation (AF) and in identifying and testing novel antiarrhythmic strategies. We aimed to develop and characterize a new experimental rat model of AF, induced by long-term transesophageal atrial electrical stimulation, and to investigate whether the "AF begets AF" concept applies to small rodent hearts. Method Twelve adult male Wistar rats were randomized into two groups: Sham (n = 5) and AF (n = 7). All rats were implanted at the beginning of the study with ECG radiotelemetry devices and underwent continuous ECG monitoring throughout the study. To induce AF, the rats in the AF group underwent atrial pacing for 10 consecutive days (15 successive cycles of stimulation/day, 20 s each, with a free interval of 5 min between cycles; 4,000 stimuli/min, stimulus duration 6 ms, voltage 3 V above the diastolic threshold). A similar procedure was applied to the Sham group, but without performing the actual electrical stimulation. The number and duration of spontaneous AF episodes were evaluated based on continuous ECG monitoring prior to, during, and for one week after transesophageal atrial pacing. The inducibility of AF and the occurrence and duration of spontaneous AF episodes were evaluated and compared between the two groups. Results Atrial fibrillation was induced in 85.7% of the rats subjected to atrial electrical pacing (Figure, A), with an average global inducibility of 44.0% ± 16.9% and a mean AF duration of 123.2 ± 96.3 s. No induced or spontaneous AF episodes were recorded in any of the Sham animals. In the AF group, none of the animals presented spontaneous AF before transesophageal atrial pacing. However, in the AF rats, after atrial electrical stimulation initiation, the number of atrial premature beats significantly increased (21.3 ± 6.8 / 24-h post-stimulation vs. 7.3 ± 6.5 / 24-h at baseline; p< 0.01; Figure, B), and all rats presented spontaneous AF episodes (Figure, C). At the end of the study, AF rats presented a total number of 23.9 ± 2.3 AF episodes / 24-h (Figure, D), with a mean AF burden of 337.7 ± 25.06 s / 24-h. Conclusions Our data demonstrate that, despite the small size of the atria, the "AF begets AF" concept is applicable in small rodents. The study presents a novel rat model of AF, in which spontaneous AF occurs following long-term atrial electrical stimulation. Given that the model is relatively rapid and easy to implement, it provides a setup for further investigation of AF pathophysiology, and for identifying and testing novel therapeutic strategies for AF.Figure 1

Real-world utility of implantable loop recorders

Abstract Background Implantable loop recorders (ILRs) allow prolonged and continuous single-lead electrocardiogram recording and have significantly shortened time to electrocardiographic diagnosis and appropriate therapy of many bradyarrhythmias and tachyarrhythmias. Purpose The aim of this retrospective single center study was to evaluate ILR indications, diagnostic yield and ILR-guided interventions. Methods We retrospectively analyzed 388 patients (223 male / 165 female), who underwent Medtronic and Biotronik ILRs implantation at a heart center. Demographic and clinical data were obtained from the medical records. Remote monitoring was analyzed when no data of in-hospital follow up could be acquired. Results The mean age at ILR implantation was 63.4 ± 14.9 years with a mean follow-up of 20.7±17.6 months from ILR implantation. In total, 152 (39.2%) patients were followed by a remote monitoring system. Number of patients with ILR indication due to syncope (n=171; 44.1%) was significantly higher compared to patients with monitoring after ablation of atrial fibrillation or atrial flutter (n=108; 27.8%), cryptogenic stroke (n=50; 12.9%) and presyncope and dizziness (n=21; 5.4%) (p<0.05). After 12 months, arrhythmia was detected in 198 cases (79.2% out of 250 patients with detected arrhythmias). The most common type of arrhythmia was paroxysmal atrial fibrillation (31.7%) with a significantly higher prevalence compared to atrial tachycardias (16.5%) and supraventricular premature beats (9.8%) (p<0.05). Noteworthy, in 132 (52.8% out of 250) patients, ILR diagnosis corresponded to the suspected arrhythmia, whereas in 118 patients unexpected arrhythmias were detected. ILR diagnosis of arrhythmia lead in 147 (58.8%) patients to initiation of a new therapy or to a change of current medication. Changes of current medication occurred in 72 patients (28.8%), electrophysiology study/ablation in 66 patients (26.4%), pacemaker/ICD implantation in 46 (18.4%), electrical cardioversion in 6 patients (2.4%), and closure of the left atrial appendage in 1 patient. Conclusion Our study shows, that ILRs are an important diagnostic tool, providing clinical relevant data in about two thirds (65%) of the patients. About half (52.8%) of the detected arrhythmia correlated with the symptoms leading to ILR implantation (number needed to treat was around 2). Remote monitoring improves the diagnostic timing with a potential reduction of costs for health care. However, patient selection is critical and ILRs benefits needs to be proven in larger randomized trials.

Safety and efficacy of a temperature-controlled ablation system for ventricular tachycardia: first results from the TRAC-VT study

Abstract Background Catheter ablation using radiofrequency (RF) energy, is a well-recognized treatment option for patients with ventricular arrhythmias. However, procedural complications may be high, and efficacy is often suboptimal with high recurrence rates. Purpose The TRAC-VT study evaluated safety and efficacy of the DiamondTemp Ablation (DTA) System for the treatment of patients with ventricular arrhythmias by catheter ablation. Methods A temperature-controlled, irrigated RF catheter (with six thermocouples and an internal network of diamond coatings) was utilized to treat subjects with either sustained monomorphic ventricular tachycardia (VT) and structural heart disease or with frequent monomorphic symptomatic ventricular premature beats (VPBs) and normal hearts. Patients were enrolled at five hospital centers in five European countries and were followed for 6 months. Ablation was performed in temperature-control mode with an irrigation flow of 8 mL/min for all power deliveries. The target temperature was set to 55 or 60 °C with a power output limited to 50 Watts. RF energy was applied for a maximum of 45 seconds per target site, depending on impedance drop and electrogram abatement. Results The study enrolled 49 subjects (age 67±12 years, 80% male) in total (38 with sustained monomorphic VT and structural heart disease and 11 with symptomatic VPBs). In all cases, mapping and navigation was used with EnSite systems (Abbott). The average ablation time (defined as time from the insertion of the DTA catheter until removal from body) was 87 ± 44 minutes. During this time, RF energy was applied for an average of 28.2 ± 10.2 seconds with a power of 44.0 ± 7.0 W and a temperature of 50.9 ± 3.9 °C during 35.0 ± 23.2 applications. Acute procedural success was 100% (93%-100%), and it was defined as the elimination of VPBs or non-inducibility for sustained VT (using solely the DTA catheter). The primary safety procedure-related endpoint was an evaluation of cardiovascular-related death, stroke / TIA, cardiac tamponade/perforation, bleeding complication, myocardial infarction, thromboembolism, and pulmonary edema. In total review of the primary safety endpoint, one subject had a confirmation of a stroke / TIA event. Regarding longer term procedural efficacy, the 6-month follow-up was completed in 92% of subjects. For the whole study population chronic success from recurrence of ventricular arrhythmia (faster than 100 beats/min after 6 months) was 73.4% (58.6%-83.6%) for non-sustained ventricular arrhythmias (≥3 beats) and 87.7% (74.7%-94.3%) for sustained ventricular arrhythmias (≥30 sec). Conclusions VT/VPBs ablation using a temperature-controlled irrigated RF catheter was safe and effective with low VT recurrence at 6 months of follow-up.

Genetic characterization of drug-induced long QT syndrome in a large prospective cohort

Abstract Introduction Drug-induced long QT syndrome (DI-LQTS) is a clinical entity with a poorly defined etiopathogenesis. Purpose The objective of the study was to determine the genetic basis of a prospective cohort of patients with DI-LQTS in the setting of a tertiary hospital center. Methods Prospective observational study with consecutive inclusion of patients with the diagnosis of DI-LQTS according to standard criteria, in a tertiary hospital, between 2018 and 2022. A genetic study was performed through massive DNA sequencing to identify variants in known genes associated with cardiopathy, arrhythmogenic and cardiomyopathy. Results 86 patients (age 65±15 years, 59% men) were included. The mean corrected QT interval (QTc) of the entire cohort was 543±56 ms. The drugs associated with QTc interval prolongation were: psychotropics 51%, antiarrhythmics 38%, anesthetics 30%, antibiotics 16%, antineoplastics 5%, others 4%. Twenty-one patients (24%) presented with ventricular arrhythmias at the time of drug-induced QTc prolongation: 10 (12%) ventricular fibrillation, 7 (8%) sustained ventricular tachycardia, 3 (3%) non-sustained ventricular tachycardia, 1 (1%) frequent ventricular premature beats. Genetic information was obtained in 83 (97%) patients. 17 pathogenic mutations associated with heart disease were identified in 15 (18%) patients: 4 (5%) patients with 5 mutations in ion channel genes (KCNE1, KCNE1B, KCNH2, RYR1, RYR2), and 12 (14%) patients with 12 mutations in genes associated with cardiomyopathy (NF1, PKD2, ABCC6, TTN, FHOD3, MYO6, COL11A1, CCDC40, CRELD1, COL4A1). Two patients had 2 pathogenic mutations each, one of them with both mutations associated with channelopathy, and another with a mutation associated with channelopathy and a second mutation related to cardiomyopathy. Only 1 patient carrying a pathogenic mutation related to cardiomyopathy had a clear phenotype, while in 3 carrier patients there was a history of transient systolic dysfunction, 2 due to tachycardiocardiopathy and 1 due to peripartum cardiomyopathy. The identification of a pathogenic mutation was not related to significant differences in QTc interval prolongation (544±63 vs 542±55 ms) or risk of ventricular arrhythmias (26% vs 24%). Conclusions The genetic basis of drug-induced long QT syndrome is essentially different from that of the congenital form of the disease. The identification of pathogenic mutations in genes associated with cardiomyopathy is relatively frequent, while those associated with ion channel genes are uncommon.

Coronary venous ethanol ablation of refractory left ventricular summit arrhythmias: comparison with radiofrequency ablation

Abstract Background Radiofrequency (RF) ablation of ventricular premature beats (VPBs) and ventricular tachycardia (VT) arising from the left ventricular (LV) summit is challenging and may fail due to anatomical inaccessibility of the substrate. Coronary Venous Ethanol Ablation (CVEA) has been suggested as a bailout strategy following failed RF ablation of LV Summit Arrhythmias (LVSA). Comparison with RF ablation strategies are lacking. Purpose To compare CVEA with RF ablation for the treatment of LVSA. Methods Between January and November 2023, 20 patients were treated with CVEA for LVSA. Results were compared to 36 patients that underwent RF ablation for LVSA (Panel A). Endo- and/or epicardial RF ablation was performed based on local signal precocity and pace-mapping. Coronary venogram-guided mapping of coronary sinus side-branches was performed using an angioplasty wire connected to our EP-recording system using a crocodile clamp. The target veins were specifically selected based on early presystolic potentials and confirmed by matching VPB pace-maps. For the treatment, angioplasty balloon(s) measuring 2-2.5×6-8 mm were employed to administer ethanol into the target branch of the coronary sinus. Data are reported as mean ± standard deviation, unless otherwise indicated. P-values are two-tailed. Results (Panel B): Patient characteristics were similar for both groups, except for the number of prior failed ablation procedures (75% males; mean age: 63 ± 13 y; 31 with structural heart disease; mean LVEF 39 ± 9%; VPB burden 25 ± 12%; Number of (NS)VT 72 ± 151; 65% redo in case of CVEA, 28% for RF). Mean pace-match was 97 ± 1% (99.8% max.) for CVEA versus 93 ± 8% (97% max.) for RF ablation (P = 0.002). Earliest presystolic signal was -70 ms (-49 ± 12) for CVEA versus -50 ms (-31 ± 12) for RF (P = 0.0002). Acute success, defined as elimination of VPB/VT was 95% versus 83% for CVEA and RF ablation respectively. VPB burden at Holter was 1 ± 3% 6-8 weeks after CVEA versus 8 ± 10% following RF ablation (P = 0.024). In patients with VT, number of (NS)VT decreased by 90% after CVEA (P = 0.014), while this was not significant for RF ablation. After a median follow-up of 8 months (IQR 2-10), 15% of CVEA patients showed residual non-LV summit ventricular arrhythmia as compared to 39% showing recurrence of LV summit VPB or VT following RF ablation. No patients died. One patient developed tamponade following RF ablation and one patient received PCI in the CVEA group. Conclusion Retrograde coronary venous ethanol ablation is an effective ablation strategy for the treatment of LV summit arrhythmias, also compared to conventional RF ablation.

Anthracycline-induced arrhythmias in breast cancer therapy: A meta-analysis of single-arm trials.

As of 2020, breast cancer has emerged as the predominant cause of cancer incidence globally. Anthracycline-based chemotherapy serves as a crucial element in the treatment regimen for breast cancer. However, these anthracycline-based drugs are associated with cardiac toxicity. This study represents the first clinical quantitative analysis aimed at accurately determining the incidences of arrhythmia and abnormal electrocardiogram (ECG) changes, thereby providing valuable data to bolster clinical drug usage and monitoring. A systematic search was conducted across multiple databases including CNKI, VIP, Wanfang, PubMed, Embase, Web of Science, and the Cochrane Library. The incidence of combined arrhythmias in breast cancer patients and the associated heterogeneity were calculated using either a random effect model or a fixed effect model. Statistical analysis was performed using STATA16. The study encompassed a total of 37 articles, which included 5705 breast cancer patients undergoing anthracycline treatment. Among these patients, 2257 developed arrhythmias. The meta-analysis revealed that the incidence of anthracycline-associated arrhythmias and abnormal ECG changes in breast cancer patients was 0.41 (0.37, 0.44). Subgroup analysis indicated that the incidence of ST-T segment change was 0.19 (0.15, 0.23), the incidence of conduction block was 0.04 (0.02, 0.05), the incidence of premature beats was 0.09 (0.07, 0.11), and the incidence of atrial fibrillation was 0.04 (0.00, 0.12). Additional results are presented in Table 3. This pioneering study accurately assesses the incidence of arrhythmias in breast cancer patients treated with anthracyclines. The findings provide clinicians with valuable insights into understanding and managing the cardiac toxicity associated with such treatment. Moreover, this study lays the foundation for future research exploring the mechanisms underlying these arrhythmias and potential preventative strategies.

Accuracy of the OMRON HEM-7361T blood pressure monitor in the differentiation between atrial fibrillation and sinus rhythm.

We investigated the accuracy of the OMRON HEM-7361T automated oscillometric blood pressure (BP) monitor in the differentiation between atrial fibrillation and sinus rhythm. An approximately equal number of patients with persistent atrial fibrillation and individuals with sinus rhythm were recruited from outpatients and inpatients of Ruijin Hospital, Shanghai, China. BP was measured three times consecutively with a 30-s interval with the OMRON HEM-7361T automatic electronic BP monitor for atrial fibrillation detection. A hand-held single lead electrocardiogram device was used for simultaneous electrocardiogram recordings. The device accurately identified atrial fibrillation in 100 (99.0%) of the 101 patients, with only 1 patient incorrectly classified as non-atrial fibrillation. The device correctly identified 99 (95.2%) of the 104 participants with sinus rhythm as non-atrial fibrillation, with five participants incorrectly classified as atrial fibrillation. The device had a positive predictive value of 95.2%, negative predictive value of 99.0%, and overall accuracy of 97.1%. Among the six misclassified participants, one with atrial fibrillation had a heart rate of 65 beats/min, and four of the five participants with sinus rhythm had cardiac arrhythmias (atrial or ventricular premature beat in one participants, sinus tachycardia in one participant, and both arrhythmias in one participant). The OMRON HEM-7361T BP monitor is accurate in the differentiation between atrial fibrillation and sinus rhythm. Whether the device is sufficiently accurate in the differentiation between atrial fibrillation and other cardiac arrhythmias remains under investigation.

Association between Preeclampsia and Long-term Risk of Arrhythmias.

Preeclampsia (PE), a pregnancy-induced hypertensive disorder, affects 4-5% of pregnancies worldwide. It is well known that hypertension is associated with an increased risk of arrhythmias; however, data on the association between PE and arrhythmias are sparse. In this observational cohort study, we identified all primiparous women who gave birth in Denmark (1997-2016) using Danish nationwide registries. The women were stratified on whether they developed PE during primiparous pregnancy, and followed from primiparous pregnancy to incident arrhythmia, emigration, death, or end of study (December 31, 2018). A total of 523,271 primiparous women with a median age of 28 years were included and 23,367 (4.5%) were diagnosed with PE. During a median follow-up of 10.1 years, women with vs without PE were associated with a higher incidence of arrhythmias (1.42% vs 1.02%): 1) Composite of cardiac arrest, ventricular tachycardia/fibrillation, or ICD implantation (adjusted HR 1.60 [95% CI 1.14-2.24]), 2) Composite of advanced 2nd degree or 3rd degree atrioventricular block, sinoatrial dysfunction, or pacemaker implantation (adjusted HR 1.48 [95% CI 0.97-2.23]), 3) Composite of supraventricular tachyarrhythmias or extra systoles (adjusted HR 1.34 [95% CI 1.19-1.51]), 4) Composite of all the above-mentioned arrhythmias (adjusted HR 1.37 [95% CI 1.23-1.54]). Preeclamptic women were associated with a significantly and at hitherto unknown long-term increased rate of arrhythmias. This finding suggests that women with PE may benefit from cardiovascular risk assessment, screening, and preventive education.

Sympathetic toggled paroxysmal atrial fibrillation and recurrent premature atrial contractions in ambulatory patients

BackgroundAutonomic nerve activity is important in the mechanisms of paroxysmal atrial fibrillation (PAF). ObjectiveThe purpose of this study was to test the hypothesis that a single burst of skin sympathetic nerve activity (SKNA) can toggle on and off PAF or premature atrial contraction (PAC) clusters. MethodsSimultaneous recording of SKNA and electrocardiogram (neuECG) recording was performed over 7 days in patients with PAF. ResultsIn study 1, 8 patients (7 men and 1 woman; age 62 ± 8 years) had 124 episodes of PAF. An SKNA burst toggled both on and off PAF in 8 episodes (6.5%) (type 1), toggled on but not off in 12 episodes (9.7%) (type 2), and toggled on a PAC cluster followed by PAF in 4 episodes (3.2%) (type 3). The duration of these PAF episodes was <10 minutes. The remaining 100 episodes (80.6%) were associated with active SKNA bursts throughout PAF (type 4) and lasted longer than type 1 (P = .0185) and type 2 (P = .0027) PAF. There were 47 PAC clusters. Among them, 24 (51.1%) were toggled on and off, and 23 (48.9%) were toggled on but not off by an SKNA burst. In study 2, 17 patients (9 men and 8 women; age 58 ± 12 years) had <10 minutes of PAF (4, 8, 0, and 31 of types 1, 2, 3, and 4, respectively). There were significant circadian variations of all types of PAF. ConclusionA single SKNA burst can toggle short-duration PAF and PAC cluster episodes on and off. The absence of continued SKNA after the onset might have affected the maintenance of these arrhythmias.

PERMANENT JUNCTIONAL RECIPROCATING TACHYCARDIA: IT IS IMPORTANT TO KNOW HOW TO RECOGNIZE IT

Abstract Permanent junctional reciprocating tachycardia, also known as Coumel‘s tachycardia, is a rare form of supraventricular tachycardia that is usually incessant, characterised by retrograde conduction via an accessory pathway usually located in the posteroseptal region with slow and decremental conduction. Tachycardia is virtually incessant, at a rate ranging from 120 to 250 beats/minute. The electrocardiogram inscribes inverted P waves in leads II, III, AVF, as well as left lateral leads, along with a P–R interval shorter than the R–P interval during the tachycardia. The characteristic, but not diagnostic, electrocardiographic feature is a long R–P interval consistent with slow retrograde conduction. Spontaneous resolution of tachycardia is not un common. Electrocardiographically, it manifests as a narrow QRS tachycardia with long RP‘, with negative retrograde “p” waves in lower leads (D2, D3 and avF). The initiation and termination of the arrhythmia is not determined by a premature beat, but by critical changes in the RR cycle, that is, for values of the heart rate at which the activating front finds the retrograde decremental pathway outside refractoriness. Due to its incessant characteristic in some cases, patients may present tachycardiomyopathy, with myocardial dilation and ventricular dysfunction. We report the case of a 5–year–old girl who came in for onset of heart palpitation for several hours. On electrocardiogram finding of supraventricular tachycardia, narrow QRS, HR 170/min, negative p waves in DII–DIII–AVF. The electrocardiographic finding was compatible with a picture of permanent junctional reciprocating tachycardia. Following the administration of 50mg of phleicanide, there is a progressive reduction in heart rate until the clinical picture stabilizes. antiarrhythmic therapy was subsequently set with subsequent re–evaluation and discharge to the patient‘s home.

REAL WORLD USAGE OF RANOLAZINE FOR ANTIARRHYTHMIC PURPOSES: SINGLE CENTER EXPERIENCE

Abstract Introduction Ranolazine is a late sodium current blocking drug developed as an antianginal agent, with good preliminary efficacy data even for antiarrhythmic purposes (both at atrial and at ventricular level). Objectives To evaluate patients’ clinical characteristics and antiarrhythmic efficacy of ranolazine in subjects with a history of atrial and/or ventricular arrhythmias, isolated or repetitive. Patients and methods we included patients who received a first prescription of ranolazine for antiarrhythmic purposes in our center from 1/2022 to 11/2023 and evaluated the survival free from major arrhythmic relapses/ablation. Results 93 patients were enrolled (66±13 years, 15% women): 59% with arterial hypertension, 26% diabetics, 46% with post–ischemic dilated heart disease, 32% with primary cardiomyopathy (including 11% with hypertrophic cardiomyopathy, 10% with LMNA, 14% with TTN), 46% with implantable cardioverter defibrillator, 9% with pacemaker. The mean LV ejection fraction was 42 ± 15%, the mean serum creatinine 1 ± 0.3 mg/dL. Half (50%) had a history of atrial arrhythmias in the 6 months before starting the drug, mainly paroxysmal atrial fibrillation (AF), 67% of ventricular arrhythmias (VAs), mainly isolated and repetitive premature ventricular beats (PVB, 47% of the total), but also sustained or treated VAs (n=18, 19%). Overall, 18% of patients had already undergone AF ablation, 13% ventricular tachycardia ablation, 3% cardiac sympathetic denervation. Finally, 95% of patients were on beta–blocker therapy and 28% were on amiodarone. Ranolazine was prescribed at an average initial dose of 535± 150 mg. The majority (54%) of patients (n=50) had a follow–up longer than 3 months (median 9 months, IQR 6–14); in 6% the drug was stopped due to intolerance and the average dose at the last FU was 641 ± 150 mg. Twenty–eight percent of patients with paroxysmal/persistent atrial arrhythmias had relapses, requiring ablation in 6%. Among patients with major VAs, 57% suffered recurrences, but only 19% required ablation (invasive in 2 cases, non–invasive in 1 case). Finally, among the patients with PVBs, none suffered major VAs or required PVB/VA ablation. Conclusions This is the largest available case–series reporting about the real–world usage of ranolazine for antiarrhythmic purposes. Our single center experience supports ranolazine’s good safety and tolerability and shows encouraging efficacy results in terms of clinical stabilization of complex patients.

Assessment of cardiac adverse events following COVID-19 vaccination by speckle tracking echocardiography

Cardiac discomfort has been reported periodically in COVID-19-vaccinated individuals. Thus, this study aimed to evaluate the role of myocardial strains in the early assessment of the clinical presentations after COVID-19 vaccination. Totally, 121 subjects who received at least one dose of vaccine within 6 weeks underwent laboratory tests, electrocardiogram (ECG), and echocardiogram. Two-dimensional speckle tracking echocardiography (2D-STE) was implemented to analyze changes in the left ventricular myocardium. After vaccination, 66 individuals (55.4 ± 17.4 years) developed cardiac discomforts, such as chest tightness, palpitations, dyspnea, and chest pain. The ECG readings exhibited both premature ventricular contractions and premature atrial contractions (n = 24, 36.4%), while none of the individuals in the control group manifested signs of cardiac arrhythmia. All had normal serum levels of creatine phosphokinase, creatine kinase myocardial band, troponin, N-terminal pro b-type natriuretic peptide, platelets, and D-dimer. Left ventricular ejection fraction in the symptomatic group (71.41% ± 7.12%) and the control group (72.18% ± 5.11%) (p = 0.492) were normal. Use of 2D-STE presented global longitudinal strain (GLS) and global circumferential strain (GCS) was reduced in the symptomatic group (17.86% ± 3.22% and 18.37% ± 5.22%) compared to the control group (19.54% ± 2.18% and 20.73% ± 4.09%) (p = 0.001 and p = 0.028). COVID-19 vaccine-related cardiac adverse effects can be assessed early by 2D-STE. The prognostic implications of GLS and GCS enable the evaluation of subtle changes in myocardial function after vaccination.

Cardiac arrhythmias in patients with type 2 diabetes mellitus

Introduction. The contribution of type 2 diabetes mellitus (type 2 diabetes) and cardiovascular diseases (CVD) to the increase in disability and mortality rates worldwide continues to grow steadily. Currently, the main focus is on the problem of atherosclerotic cardiovascular diseases (ACCD) in DM, while the manifestations of cardiac arrhythmias (LDC) in conditions of carbohydrate metabolism disorders have not been sufficiently studied.The purpose of the study. To analyze and compare laboratory, instrumental and objective indicators in patients with type 2 diabetes mellitus (type 2 diabetes mellitus) and without, who have a history of cardiac arrhythmias (LDC).Materials and methods. 103 patients with LDC (52 men and 51 women) were examined. 2 groups were formed: the main group – patients with LDC and type 2 diabetes (n=51) (group 1), the control group – patients with LDC without diabetes (n=52) (group 2). A comparative analysis of laboratory-instrumental and clinical-anamnestic data in the groups was performed. Statistical data processing was performed using the statistical software package "Excel" ("Microsoft"), the program "Statistica 10" ("Statsoft Inc"). The value of p &lt;0.05 was taken as the significance level. The reliability of the differences between the groups was determined using the Mann-Whitney U-test, and the correlation analysis was carried out using the Spearman criterion.Results. The average age of the general group was 67[18;97] years, patients with type 2 diabetes 69 [53;93] years, patients without diabetes 65 [18;97] years. According to the performed regression analysis, it was found that DM in patients was associated with the detection of atrial fibrillation (OR 2.69 (95% CI 1.076;6.71), p=0.034), in particular, its constant form (p=0.025, coefficient. Kramer's V = 0.33), as well as with the presence of supraventricular extrasystole (NJES) (OR 0.235 (95%CI 0.09;0.59), p=0.002, coefficient. Kramer's V = 0.311). At the same time, there was no significant association of DM with the presence of paroxysmal and persistent forms of atrial fibrillation, atrial flutter (TP), BLNPG, AV block, CA block, ventricular extrasystole, supraventricular tachycardia (NVT) and SSSI.When evaluating the functional parameters of the myocardium according to Echo-K G data, it was found that in the main group, compared with the control group, significant (34% vs. 27%) and pronounced (18% vs. 6%) pulmonary hypertension were more common, but the difference was not statistically significant (p&gt;0.05).When assessing the structural and geometric parameters of the myocardium, it was found that concentric myocardial hypertrophy was more common in the main group (22% vs. 15%), and in the control group – concentric myocardial remodeling (14% vs. 25%), (p&gt;0.05).Conclusions. DM is a significant risk factor for a more severe course of LDC, in particular atrial fibrillation and supraventricular ectopias. In this regard, it is of fundamental importance to control carbohydrate metabolism and prevent risk factors for cardiovascular diseases in order to preserve the basic functions of the myocardium and improve the quality of life of patients with diabetes mellitus.

A Case Report of Arrhythmia Caused by Skin Expander Implantation

A 51-year-old female patient suffered facial burns during her youth. Following the healing of the wound, a skin expander was implanted on 7 December 2021 to address scar contracture. The preoperative electrocardiogram (ECG) indicated sinus rhythm within the normal range. Color Doppler ultrasound revealed no abnormalities. The patient had no history of hypertension, heart disease, diabetes, arrhythmia, or other cardiovascular and cerebrovascular conditions. On 16 June 2022, the skin expander was removed, and facial scar resection was performed. The routine ECG showed ventricular premature beats. During the operation, when the surgeon pulled and compressed the neck dilator, significant arrhythmia was observed, with the heart rate dropping below 50 beats per minute and frequent ventricular premature beats occurring. The surgeon promptly halted the procedure, resulting in immediate relief of the patient's pain. Subsequently, the ventricular premature beats ceased, and normal sinus rhythm was restored. Once the heart rate exceeded 60 beats per minute, the surgeon resumed the operation, but ventricular premature beats persisted. After removing the dilator, the heart rate gradually returned to normal, and no further arrhythmia occurred. The patient recovered smoothly post-operation, with stable vital signs and no reported discomfort. She safely returned to the ward. It was determined that the patient's arrhythmia was caused by the compression of the carotid sinus due to the stretching of the neck dilator.

Predictors of paroxysmal atrial fibrillation: Analysis of 24-hour ECG Holter monitoring

main predictors of the development of this arrhythmia. Material and methods.A single-center, cross-control study was conducted. Of all 6630 protocols analyzed, according to 24-hour ECG monitoring, AF paroxysm was detected in 97 people as an accidental finding. These patients were included in the main study group. The control group consisted of 99 patients from the same cohort without paroxysmal AF, having the anthropometric and comorbidity parameters similar to the patients of the main group. Results.In the absolute majority (97.9%) of patients in the main group in whom paroxysmal AF was detected, a special variant of extrasystole was revealed – early atrial “P on T” type (versus 4.0% in patients in the control group) [OR 8461.648 (382.1983;187336)]. The number of supraventricular single, paired and group extrasystoles was significantly higher in the main group, but the number of ventricular extrasystoles did not differ significantly. Conclusion.One of the main ECG predictors for the development of paroxysmal AF in asymptomatic patients is the appearance of supraventricular extrasystole of the “P on T” type. In the mechanism of formation of AF paroxysm during supraventricular extrasystole of the “P on T” type, not only electrophysiological mechanisms play a role, but also the heart biomechanics.

A graph-based cardiac arrhythmia classification methodology using one-lead ECG recordings

In this study, we present a novel graph-based methodology for an accurate classification of cardiac arrhythmia diseases using a single-lead electrocardiogram (ECG). The proposed approach employs the visibility graph technique to generate graphs from time signals. Subsequently, informative features are extracted from each graph and then fed into classifiers to match the input ECG signal with the appropriate target arrhythmia class. The six target classes in this study are normal (N), left bundle branch block (LBBB), right bundle branch block (RBBB), premature ventricular contraction (PVC), atrial premature contraction (A), and fusion (F) beats. Three classification models were explored, including graph convolutional neural network (GCN), multi-layer perceptron (MLP), and random forest (RF). ECG recordings from the MIT-BIH arrhythmia database were utilized to train and evaluate these classifiers. The results indicate that the multi-layer perceptron model attains the highest performance, showcasing an average accuracy of 99.02%. Following closely, the random forest achieves a strong performance as well, with an accuracy of 98.94% while providing critical intuitions.

Role of Exercise Stress Test in Evaluating Athletes with Premature Ventricular Beats: A Retrospective Study

Role of Exercise Stress Test in Evaluating Athletes with Premature Ventricular Beats: A Retrospective Study