Search Results (58)

Transseptal puncture (TSP) is an essential step for left heart procedures that allows access to the left atrium (LA) through the fossa ovalis (FO) of the interatrial septum (IS). Initially developed for diagnostic purposes, today, it is performed for procedures that require large-bore device delivery systems and complex three-dimensional navigation in the left atrium. TSP supports various interventions, including atrial fibrillation ablation, left atrial appendage closure, and transcatheter mitral valve repair and replacement. While traditionally performed with Brockenbrough needles under fluoroscopic guidance, the integration of transesophageal and intracardiac echocardiography (TEE/ICE) has significantly improved its safety and precision. Despite its generally high success rate, TSP poses challenges in complex anatomies or for less experienced operators, with complications such as cardiac tamponade, aortic root puncture, and embolic events. Anatomical variations, such as thickened or floppy septa, further complicate the procedure. Technological advancements, including radiofrequency-based systems and specialized guidewires, have enhanced safety in difficult cases. Effective training, including echocardiography and complication management, is vital for operator proficiency. This review outlines the procedural steps for safe TSP, emphasizing proper equipment selection, anatomical considerations, and vascular access techniques. Common complications are discussed alongside management strategies. Advanced tools and techniques for addressing challenging scenarios are highlighted. Full article

Hypertrophic cardiomyopathy is the most prevalent inherited cardiac condition, distinguished by an autosomal dominant inheritance pattern. Diagnosis can be achieved through echocardiography, cardiac magnetic resonance imaging, and genetic testing. Recently, significant advancements have occurred in pharmacological and invasive therapies that are transforming the management of hypertrophic cardiomyopathy, including the introduction of cardiac myosin inhibitors, radiofrequency ablation, and gene editing. Additional trials are being conducted on investigational therapies, with the results anticipated in the near future. This review aims to provide a concise overview of both currently approved and investigational treatments for hypertrophic cardiomyopathy. Full article

Radiofrequency ablation (RFA) is a pivotal therapeutic technique for various medical conditions, including cardiovascular disease and oncological conditions such as liver and lung cancer. The energy-controlled mode in RFA procedures allows for uniform energy delivery but is less safe compared to the temperature-controlled mode. Therefore, it is necessary to develop a protocol that ensures safety while efficiently delivering energy in the temperature-controlled mode. In this study, we compared lesion formation using the gradual-temperature-rise mode to the fixed-temperature mode. We evaluated the lesion size, energy, cumulative time efficiency, and procedural safety in both in vitro and in vivo experiments with porcine myocardial tissue. Three experimental groups (n = 6) were compared to assess the effect of gradual-temperature-rise and fixed-temperature ablation modes. Five experimental groups (n = 6) were used to determine the optimal temperature turn-up time. The gradual-temperature-rise mode ablated larger lesions (10.48 ± 0.56 mm) compared to the 75 °C (7.67 ± 0.37 mm) and 85 °C (8.05 ± 0.36 mm) fixed-temperature groups (p = 0.002). The optimal turn-up time for efficient lesion formation was found to be between 120 and 180 s. The in vivo experiments validated the safety and efficacy of the optimized gradual-temperature-rise mode. Therefore, using the gradual-temperature-rise mode of temperature-controlled RFA enhances lesion formation, energy transfer, and safety, making it a promising approach for clinical application in cardiac ablation procedures. Full article

The cornerstone of ablative therapy for atrial fibrillation (AF) is pulmonary vein isolation (PVI). Whether PVI should be added with additional lesions in persistent atrial fibrillation (PerAF) or for any post-ablative recurrent AF is a matter of debate. Whatever the ablative strategy, it must determine the choice of energy source to achieve the most durable lesion sets with the least likelihood of complications. Radiofrequency (RF) is the most studied thermal ablation technique. It can be combined with high-density electroanatomic mapping and can be used for both pulmonary and extrapulmonary atrial ablation. Cryoenergy is at least as effective as radiofrequency for PVI; it is rapid, relatively safe, and has a steep learning curve. Therefore, it has been proposed as a first-line approach for PVI-only procedures. More recently, a non-thermal technique based on the application of pulsed direct current (Pulsed Field Ablation—PFA) has been introduced. PFA causes cell death by opening cell membrane pores (electroporation) without a significant increase in tissue temperature. It is fast and does not alter the extracellular matrix as thermal techniques do, although it ends up causing long-lasting, transmural lesions. Most importantly, it is relatively selective on cardiac myocytes and therefore potentially safer than thermal techniques. Some PFA systems can be combined with electroanatomic mapping systems. However, as of now, it appears that these ablation technologies should be considered complementary rather than alternative for a number of practical and theoretical reasons. Full article

Although most research has concentrated on the link between sleep apnea and atrial fibrillation, obstructive sleep apnea (OSA) is also associated with ventricular arrhythmias. These cardiac arrhythmias can be triggered by repeated episodes of hypoxemia, hypercapnia, acidosis, intrathoracic pressure fluctuations, reoxygenation, and other mechanisms that occur during apnea and hypopnea. Studies show that OSA reduces the effectiveness of arrhythmia treatments, such as antiarrhythmic medications and radiofrequency current ablation. Several non-randomized studies indicate that treating sleep apnea syndrome with continuous positive airway pressure (CPAP) may help maintain sinus rhythm following electrical cardioversion and increase the success rates of catheter ablation. This review aims to thoroughly examine the role of OSA in the development of cardiac arrhythmias. Screening for OSA and arrhythmias in patients with OSA provides vital information on the need for additional interventions, such as CPAP therapy, anticoagulation, antiarrhythmic drug therapy, catheter ablation for specific arrhythmias, or device therapy. New therapies for OSA treatment have the potential to significantly influence arrhythmia development in patients with sleep-disordered breathing. However, further research is required to validate these findings and formulate comprehensive treatment protocols. Full article

Multifocal ectopic Purkinje-related premature contractions (MEPPC) syndrome is a recently recognized rare form of arrhythmia involving the entire His–Purkinje system and often coinciding with dilated cardiomyopathy (DCM). Certain variants in the SCN5A gene may be linked to MEPPC syndrome. We present a case of a 32-year-old Caucasian female who exhibited a high burden of premature ventricular contractions (PVCs) and non-sustained episodes of ventricular tachycardia (NSVT) with an alternating QRS pattern, and who was resistant to traditional medical therapy and radiofrequency catheter ablation (RFCA), necessitating implantation of a cardioverter-defibrillator (ICD). A positive family history (father’s death at the age of 40 years) and the rapid deterioration of left ventricular function parameters echocardiographically during recurrent arrhythmic episodes raised concern about a potentially complex disease scenario. Genetic testing revealed a heterozygous variant of the SCN5A gene, c.2440C>T, p.(Arg814Trp), confirming the diagnosis of MEPPC syndrome. Treatment with a combination of class I antiarrhythmic drugs, flecainide and mexiletine, concomitant with beta blockers, led to symptomatic improvement, a reduction of PVCs (from 66 491 (44%) to 858 (1%)), and the restoration of left ventricular function (LV EF from 44% to 53%). A lack of defined diagnostic criteria hampers timely diagnosis, leading to ineffective interventions and delayed initiation of treatment with antiarrhythmic drugs. MEPPC patients remain at significant risk for severe heart failure and sudden cardiac death. Our clinical case report underscores the importance of accurate and timely diagnosis, which allows effective treatment with a combination of antiarrhythmic drugs and mitigates the risk associated with MEPPC syndrome. Full article

Objectives: The goal of this study is to document outcomes of ablation for high-risk accessory pathways in paediatrics using 3D mapping systems with minimal to zero fluoroscopy. Methods: It is a cross-sectional, multicentre study, conducted between 2013 and 2023, and involving four different centres in Hungary, Croatia, Kuwait, and Slovenia. Results: A total of 128 procedures were performed on 111 patients. The cohort included 57.8% anteroseptal (AS) pathways and 42.2% midseptal (MS) pathways. The mean follow-up time was 2.0 ± 2.1 years. Cryoablation was used in 72.7% of the cases, and radiofrequency ablation was used in 27.3%. The EnSite Precision™ Cardiac Mapping System was the predominant system used. The overall acute success rate was 89.1%, with recurrence rates at 17.2% with similar results regardless of the type of energy used. The success rate was not significantly different between AS and MS substrates. The age and weight of the patient had no bearing on the outcomes (median age and weight were 13 years and 52 kg, respectively). The complications rate was at 4.69% and included transient AV block (three patients), hematoma (one patient), right bundle branch block (one patient), and possible permanent complete AV block (one patient). Fluoroscopy was utilized in 18 cases, with a fluoroscopy time mean of 3 min and 45 s. Conclusions: MS and AS AP in paediatric patients can be treated effectively with either RF or cryoablation and with a low dose of radiation using 3D mapping systems, with excellent acute success rates and low complication rates. Full article

Catheter ablation for ventricular tachycardia (VT) in patients with systolic heart failure remains a critical yet challenging area of non-pharmacological therapy. Despite positive outcomes in atrial fibrillation, evidence for the efficacy of VT ablation in reducing cardiac mortality is inconclusive due to the absence of standardized ablation strategies. The primary challenges include difficulties in identifying suitable ablation targets and their deep locations within myocardial tissue. Current techniques, such as voltage mapping, provide valuable insights; however, they are limited by the presence of numerous bystander areas and the occurrence of incomplete transmural scarring. Recent advancements in functional substrate mapping have focused on identifying critical isthmuses without requiring hemodynamic stabilization during VT, thereby shifting the emphasis to the analysis of potentials during baseline rhythm. While methods like isochronal late activation mapping have improved target identification, they primarily address conduction abnormalities without adequately considering repolarization heterogeneity. This review highlights emerging technologies that utilize unipolar potentials to assess repolarization heterogeneities and identify VT isthmuses. Furthermore, novel ablation sources such as pulsed-field ablation, bipolar ablation, and ultra-low temperature cryoablation are being explored to create deeper and more durable lesions, addressing the limitations of traditional radiofrequency ablation. These advancements aim to reduce VT recurrence and improve overall treatment efficacy. Ultimately, understanding these innovative strategies is expected to optimize procedural outcomes and significantly enhance the management of patients with scar-related VT. Full article

This prospective study evaluates the impact of radiofrequency ablation (RFA) on cardiorespiratory indicators in patients with long-standing persistent atrial fibrillation admitted to the Heart Center UMC between January 2022 and April 2024 in Astana, Kazakhstan. The study aims to assess the functional cardiac benefits of RFA. Out of 717 registered atrial fibrillation patients, 104 were examined before and 3 months after ablation, focusing on cardiorespiratory parameters. A before-and-after analysis using linear mixed models was applied to evaluate changes in cardiorespiratory parameters post-RFA. Significant improvements were noted across various measures. VO₂ max increased from 11.5 ± 4.4 mL/kg/min to 18.0 ± 4.5 mL/kg/min (p < 0.001). Oxygen uptake improved from 7.2 ± 2.6 mL/beat to 11.0 ± 3.4 mL/beat (p < 0.001). The 6-min walking test distance rose from 306 ± 82 m to 400 ± 48 m (p < 0.001). METs increased from 4.4 ± 1.6 to 8.0 ± 1.3 (p < 0.001). Heart rate at peak exercise decreased from 175.5 ± 18.6 to 147.2 ± 12.3 beats per minute (p < 0.001). NT-proBNP levels decreased from 1357 ± 1182 to 415 ± 339 pg/mL (p < 0.001). Patients with persistent atrial fibrillation undergoing RFA showed functional improvements in CPET indicators such as VO₂ max, METs, O₂ pulse, heart rate, and the 6-min walking test. Improvements were also seen in Nt-proBNP analysis. These results emphasize the need for longitudinal follow-up to optimize outcomes and minimize medical risks. Full article

Hypertrophic cardiomyopathy (HCM) is characterized by excessive growth of myocardial tissue, most commonly due to genetic mutations in sarcomere proteins. This can lead to complications such as heart failure, mitral regurgitation, syncope, arrhythmias, sudden cardiac death, and myocardial ischemia. While we have come a long way in our understanding of the pathophysiology, genetics, and epidemiology of HCM, the past 10 years have seen significant advancements in diagnosis and treatment. As the body of evidence on hypertrophic cardiomyopathy continues to grow, a comprehensive review of the current literature is an invaluable resource in organizing this knowledge. By doing so, the vast progress that has been made thus far will be widely available to all experts in the field. This review provides a comprehensive analysis of the scientific literature, exploring both well-established and cutting-edge diagnostic and therapeutic options. It also presents a unique perspective by incorporating topics such as exercise testing, genetic testing, radiofrequency ablation, risk stratification, and symptomatic management in non-obstructive HCM. Lastly, this review highlights areas where current and future research is at the forefront of innovation in hypertrophic cardiomyopathy. Full article

Background/Objectives: Most data on radiofrequency (RF) effects come from ex vivo or in vitro studies that quantify lesions using width and/or depth, while electrophysiologists use manufacturers’ indirect indices. The objective of this study was to evaluate RF lesion volume by high-resolution MRI of excised lesions in an in vivo porcine model, comparing a low-energy long-duration (LE) (20 W, 50 s) RF application strategy with a high-energy short-duration (HE) (50 W, 20 s) one. Methods: Eighteen piglets were divided into LE (n = 9) and HE groups (n = 9). RF applications were performed at four locations in both atria. Animals were sacrificed after 5–7 days, and RF lesion specimens were excised, fixed, and analyzed by 9.4 Tesla MRI. RF lesion volume, variability (variance), depth, and any extracardiac lesions were compared between the groups. Results: Seventy RF applications were performed (36 LE, 34 HE). MRI analyzed 26 LE and 28 HE samples. The HE group showed 35% higher volume than the LE group (100.2 mm³ (±81.2) in LE vs. 178.3 mm³ (±163.7) in HE, p = 0.033). RF volume variance was 6.6 mm³ in LE and 40.3 mm³ in HE. The HE group had more complications (seven vs. zero, p = 0.02) and extracardiac lesions (18 vs. 14, p = 0.613). Conclusions: There was large and unpredictable variability in RF injury on the atrial wall, even under controlled conditions, which could explain arrhythmia recurrences. The greatest lesion variability was found during HE applications. The dose/effect relationship of RF needs careful study for treating cardiac arrhythmias. Full article

Background: Atrial fibrillation (AF) is the most common cardiac arrhythmia globally. High-power, short-duration radiofrequency (RF) catheter ablation (CA) for AF has recently emerged, reducing ablation times and enhancing patient tolerability with comparable efficacy and safety. While the benefits of general anesthesia (GA) for standard-power, standard-duration CA are well-established, data comparing GA to mild conscious sedation (MCS) for high-power, short-duration CA are limited. Methods: We included patients undergoing high-power, short-duration CA for AF under GA (group 1) or MCS (group 2). Procedural characteristics, success rates, and mid-term outcomes were compared. Results: In total, 131 patients, 47 in the GA group and 84 in the MCS group, were included. CA was performed for paroxysmal AF in 34 patients in group 1 (72.3%) and 68 patients in group 2 (80.9%). We found lower a mean total procedure time (100 [90–120] vs. 160 [130–180] min, p < 0.0001), lower radiation exposure (932.5 [625–1716] vs. 2445 [1228–4791] μGy, p < 0.0001 and 4.5 [3–7.1] 7.3 [4.2–13.5] min, p = 0.0003) and fewer RF applications (71 [54.8–83.8] vs. 103 [88.5–120.5], p < 0.0001) in the GA group. No major complications occurred. The 6-month AF recurrence rate was comparable between the groups (21.2% vs. 33.3%, p = 0.15). Conclusion: In patients undergoing high-power, short-duration RFCA for AF, the use of GA is associated with better procedural efficiency while simultaneously associated with an early recurrence rate comparable to MCS. Full article

In this paper, we report on the use of a purpose-built hybrid solid-state microwave and radiofrequency generator operating at frequencies of 2.45 GHz and/or 480 kHz for cancer ablation in various tissues. The hybrid generator was tested ex vivo on chicken breast and bovine liver and has demonstrated that the high accuracy of the power delivered to the sample can be achieved by controlling the emitted power versus the temperature profile of the treated sample. In particular, the hybrid generator incorporates control systems based on impedance or reflected power measurements that allow controlled ablation without causing unwanted carbonization and without including areas where tissue damage is not desired. The results of the ex vivo tests showed that radiofrequency ablation (RFA) could be effective for performing controlled ablations with minimally invasive probes, such as cardiac pathologies, small lesions, and tissues with particular composition, while microwave ablation (MWA) could be optimal for performing large ablations in highly vascularized tissues, such as liver cancer, where it is necessary to achieve higher temperatures. Full article

Background: It has been shown that obesity and a higher body mass index (BMI) are associated with a higher recurrence rate of atrial fibrillation (AF) after successful catheter ablation (CA). The same has been proven for the left atrial volume index (LAVI). It has also been shown that there is a correlation between LAVI and BMI. However, whether the LAVI’s prognostic impact on AF recurrence is BMI-independent remains unclear. Methods: We prospectively included 62 patients with paroxysmal AF who were referred to our institution for CA. All patients underwent radiofrequency CA with standard pulmonary veins isolation. Transthoracic 2-D echocardiography was performed one day after CA to obtain standard measures of cardiac function and morphology. Recurrence was defined as documented AF within 6 months of the follow-up period. Patients were also instructed to visit our outpatient clinic earlier in case of symptoms suggesting AF recurrence. Results: We observed AF recurrence in 27% of patients after 6 months. The mean BMI in our cohort was 29.65 ± 5.08 kg/cm² and the mean LAVI was 38.04 ± 11.38 mL/m². We further divided patients into two groups according to BMI. Even though the LAVI was similar in both groups, we found it to be a significant predictor of AF recurrence only in obese patients (BMI ≥ 30) and not in the non-obese group (BMI < 30). There was also no significant difference in AF recurrence between both cohorts. The significance of the LAVI as an AF recurrence predictor in the obesity group was also confirmed in a multivariate model. Conclusions: According to our results, the LAVI tends to be a significant predictor of AF recurrence after successful catheter ablation in obese patients, but not in normal-weight or overweight patients. This would suggest different mechanisms of AF in non-obese patients in comparison to obese patients. Further studies are needed in this regard. Full article

Background: The advancement of medical interventions towards minimally invasive procedures highlights the crucial role of precise pre-procedural evaluation, particularly in catheter-based treatments for heart and cardiovascular conditions. This study investigates innovative techniques such as mitral loop cerclage (MLC) and transcatheter intramyocardial radiofrequency ablation (TIRA), emphasizing the importance of preprocedural cardiac CT scans for accurate anatomical guidance in these emerging therapies. Purpose: The objective of this study was to assess the cardiac cycle through examination of the proximal septal vein (ps) for mitral loop cerclage and the distal septal vein (ds) for transcatheter intramyocardial radiofrequency ablation. Materials and Methods: Forty patients (mean age 59.4 ± 14.7 years) undergoing third-generation dual-source computed tomography (DSCT) for chest pain evaluation were enrolled. CT scans, utilizing dual-energy CT (DECT) with iopamidol and saline, encompassed the carina to the heart base. A noise-optimized linear blended image was reconstructed at 10% intervals throughout the cardiac cycle, and the presence of ps and ds in each phase was noted by two radiologists. Results: This study identified ps in 62.5% and ds in 72.5% of patients, with both present in 45% of cases. The observation of septal veins occurred more frequently in the sequence of 70, 60, 40, 80, 30, 20, and 10% for ps, and 60, 70, 40, 80, 30, 90, 20, and 10% for ds, respectively. Conclusions: DECT in cardiac imaging is instrumental in assessing septal vein frequency. The 70% phase is optimal for MLC, while the 60% phase is preferred for TIRA. Full article