Cardiac Electrophysiology Laboratory Research Articles

Evaluating the efficacy of pre-ablation algorithms in WPW syndrome localization: a retrospective study

Abstract Background and Objective Wolf-Parkinson-White (WPW) syndrome is a congenital condition that can be diagnosed at any age and may lead to dysrhythmias, most notably atrioventricular reentrant tachycardia (AVRT). Ablation of the accessory pathway responsible for the disorder has become a standard treatment approach. The success of ablation therapy is closely linked to accurately localizing the accessory pathway. Consequently, algorithms have been developed to predict the location of the accessory pathway using pre-ablation electrocardiography (ECG) parameters. This study aims to evaluate the predictive values of previously published algorithms. Method This study included 122 patients diagnosed with WPW syndrome who underwent successful ablation of a manifest accessory pathway at our university's cardiac electrophysiology laboratory between 2019 and 2023. We retrospectively examined these patients' baseline characteristics and their procedures' features. Additionally, a team analyzed their baseline electrocardiograms (ECGs) using the EASY-WPW, Pambrun, and St. George algorithms. The sensitivity, specificity, PPV, and NPV of these algorithms were then calculated based on the location of the accessory pathways identified during the patients’ ablation treatments. Results The median age of the patients in this study was 33 years (18 - 79). Among them, 65 patients (53.3%) were male (Table 1). Ablation treatment was conducted using a 3D mapping system for all included patients, considering only those who achieved acute procedural success for analysis. The most frequently observed accessory pathway localization was the posteroseptal region of the tricuspid annulus, found in 48 patients (39.3%). Regarding the accuracy of accessory pathway prediction, the EASY-WPW, Pambrun, and St. George algorithms demonstrated correct localization rates of 81%, 72%, and 62%, respectively. The efficacy of these predictions varied according to the specific localization of the accessory pathways (Table 2). Conclusion This study highlights the limitations of previously published algorithms in predicting the localization of accessory pathways in WPW syndrome. The notably lower success rates observed in our research, as compared to earlier studies, might be attributed to variations in how localization is defined across studies, differences in the interpretation of these algorithms by users, or evolving definitions of localization resulting from advancements in 3-dimensional mapping systems. Given these findings, there is a clear need for the development of new algorithms that incorporate current localization definitions and are validated in larger patient cohorts.

Novel training concept utilizing a real world-like EP simulator

Abstract Background Training in the field of invasive cardiac electrophysiology (EP) is challenging and requires intellectual skills related to the interpretation of intracardiac electrograms. Classic approach to education of young electrophysiologists focused solely on theoretical knowledge and overseen procedures in patients as no real life like simulation of complete diagnostic and therapeutic EP studies was available. Purpose The purpose of this study was to assess a novel tool for EP training based on fully interactive, online simulator providing real clinical experience to the users. Methods EP Simulator replicates EP recording system routinely used in cardiac electrophysiology laboratories and therefore enable easier transition from training to clinical situation. Users are able to access a fully functional system with simulated surface electrocardiogram and intracardiac electrograms mimicking signals recorded by a catheter located at high right atrium, His bundle, coronary sinus, and right ventricular apex. Normal electrophysiology study and the following cardiac arrhythmias are available for simulation: sick sinus syndrome, AV conduction blocks, atrial ectopy, atrial flutter and fibrillation, atrio-ventricular and atrio-ventricular nodal reentrant tachycardia and ventricular tachycardias. Evaluation by 40 electrophysiologists (mean experience 8±6y) from 16 countries was collected via online questionnaire. Results Realism of ECG signals was described as excellent or very good by 90% of responders, realism of intracardial signals by 82.5%. Realism of signal interactions and user experience was judged as excellent or very good by 75% and 70%, respectively. 100% of users agree definitely or mostly that EP Simulator helps to translate theoretical into practical knowledge. 97.5% of responders would include it in EP training programs as it is extremely or very useful for training purposes in opinion of 87.5%. 72.5% of responders think that training on EP simulator can potentially reduce rate of complications. In 87.5% the overall experience of EP simulator was completely or mostly satisfying and it would be recommended by 100% of respondents. Conclusion EP simulator is a feasible tool for training of young electrophysiologist and it may be potentially included in cardiologist curriculum. We should particularly emphasize the positive respondents’ evaluation of EP simulator overall realism. Further systematic evaluation of the training progress is needed.

Chinese expert consensus on the construction of the fluoroless cardiac electrophysiology laboratory and related techniques.

Transcatheter radiofrequency ablation has been widely introduced for the treatment of tachyarrhythmias. The demand for catheter ablation continues to grow rapidly as the level of recommendation for catheter ablation. Traditional catheter ablation is performed under the guidance of X-rays. X-rays can help display the heart contour and catheter position, but the radiobiological effects caused by ionizing radiation and the occupational injuries worn caused by medical staff wearing heavy protective equipment cannot be ignored. Three-dimensional mapping system and intracardiac echocardiography can provide detailed anatomical and electrical information during cardiac electrophysiological study and ablation procedure, and can also greatly reduce or avoid the use of X-rays. In recent years, fluoroless catheter ablation technique has been well demonstrated for most arrhythmic diseases. Several centers have reported performing procedures in a purposefully designed fluoroless electrophysiology catheterization laboratory (EP Lab) without fixed digital subtraction angiography equipment. In view of the lack of relevant standardized configurations and operating procedures, this expert task force has written this consensus statement in combination with relevant research and experience from China and abroad, with the aim of providing guidance for hospitals (institutions) and physicians intending to build a fluoroless cardiac EP Lab, implement relevant technologies, promote the standardized construction of the fluoroless cardiac EP Lab.

Ideal Anesthetic Agent for Cardiac Electrophysiology Study and Catheter Ablation – A Pilot Study

Objectives: Patients suffering from supraventricular tachycardia (SVT) require diagnostic or therapeutic intervention in a cardiac electrophysiology (EP) laboratory. Some anesthetic medications may adversely affect cardiac EP and conduction, altering the ability to induce the arrhythmia, and may have a negative impact on the ablation treatment. This prospective, randomized, pilot study was conducted in the cardiac EP laboratory of a tertiary care hospital with the aim to identify the ideal anesthetic agent for cardiac EP study and catheter ablation of SVT. The primary objective was to compare the effects of anesthetic agents on cardiac electrophysiological parameters and arrhythmia inducibility. The secondary objective was to compare the patient, anesthesiologist, and cardiologist satisfaction scores with respect to the anesthetic agent used. Materials and Methods: Thirty adult patients with SVT for EP study and radiofrequency catheter ablation were administered either of the anesthetic agents: midazolam, fentanyl, propofol, ketamine, or sevoflurane titrated to produce conscious sedation corresponding to bispectral index (BIS) values between 71 and 90. Electrophysiological parameters were recorded before and after administering the anesthetic agent. Results: Arrhythmia could be induced in all patients. Although electrophysiological parameters remained stable with ketamine administration; higher values of the Richmond Agitation Sedation Scale score and BIS were recorded. Propofol and sevoflurane administration was associated with deviation in electrophysiological parameters more than fentanyl and midazolam. The highest values of patient, anesthesiologist, and cardiologist satisfaction scores were obtained in the fentanyl group and the lowest in the ketamine group (P < 0.002). Conclusion: In doses used to provide conscious sedation, fentanyl provided ideal conditions, and midazolam, propofol, sevoflurane, and ketamine provided satisfactory conditions for conducting EP study and catheter ablation for supraventricular tachyarrhythmias. The potential of propofol to impede cardiac conduction needs to be explored further.

Assessment of the Interelectrode Distance Effect over the Omnipole with High Multielectrode Arrays.

The development of high-density multielectrode catheters has significantly advanced cardiac electrophysiology mapping. High-density grid catheters have enabled the creation of a novel technique for reconstructing electrogram (EGM) signals known as "omnipole," which is believed to be more reliable than other methods, especially in terms of orientation independence. This study aims to evaluate how distance affects the omnipolar reconstruction of EGMs by comparing different configurations. Using an animal set up of perfused isolated rabbit hearts, recordings were taken using an ad hoc high-density epicardial multielectrode catheter. Inter-electrode distances ranging from 1 to 4 mm were analysed for their effect on the quality of resulting EGMs. Two biomarkers were computed to evaluate the robustness of the reconstructions: the areas contained within the bipolar loops and the amplitudes of the omnipoles. We hypothesised that both bipolar and omnipolar electrograms would be more robust at shorter inter-electrode distances. The results showed that an increase in distance triggers an increase in loop areas and amplitudes, which supports the hypothesis. This finding provides a more reliable estimate of wavefront propagation for the cross-omnipolar reconstruction method. These results emphasise the importance of distance in cardiac electrophysiology mapping and provide valuable insights into the use of high-density multielectrode catheters for EGM reconstruction.Clinical Relevance- The results of this study have direct clinical relevance in the application of the described techniques to recording systems in the cardiac electrophysiology laboratory, enabling clinicians to obtain more precise characterisation of signals in the myocardium.

A hub-and-spoke model: the role of satellite cardiac electrophysiology laboratory units in mitigating the waiting list pressures for catheter ablation for atrial fibrillation

Abstract Funding Acknowledgements Type of funding sources: None. Background Since setting up the cardiac electrophysiology (EP) service at our tertiary centre (UH) in 2010, there has been a significant increase in referrals for EP procedures especially catheter ablation for atrial fibrillation (AF). UH serves a catchment area of above 1 million people and the increasing demand coupled with limited resources in a publicly funded health system has led to a huge supply-demand mismatch in our AF ablation waiting list. This mismatch was compounded by the COVID-19 pandemic. Aim To share our experience of how we attempted to mitigate the waiting list pressures on our AF ablation procedures before and during the pandemic by utilising satellite cardiac EP laboratory units. Methods Firstly, we made cryoballoon pulmonary vein isolation (PVI) the initial ablation strategy for all of our paroxysmal and persistent AF patients undergoing catheter ablation (due to shorter procedure times and standardised workflow). All cryoballoon PVI cases were performed under local anaesthesia. In 2016, we transitioned from overnight-stay to same-day AF ablation and demonstrated its safety and cost-effectiveness. Finally, we increased our EP laboratory capacity by developing a hub-and-spoke model in collaboration with 2 secondary care centres regionally (WH & StX). From May 2019, cryoballoon PVI cases were performed at 3 sites: UH (hub) and 2 satellite units (WH & StX). During the pandemic, 3 national lockdowns were declared (23/3/20, 5/11/20, 6/1/21) and national healthcare services were restructured. Urgent inpatient cardiac EP cases were still performed at UH but elective EP procedures across all three sites (UH, WH & StX) were cancelled during the first national lockdown. One of the steps taken to mitigate the impact of the pandemic on our increasing AF ablation waiting list was to collaborate with the private sector (MH) which functioned as a ‘clean’ site for elective EP procedures. Cryoballoon PVI cases resumed within 2 months of the first national lockdown. From September 2020, all 3 sites [UH and its two satellite units (WH & MH)] were performing cryoballoon PVI. Data from every EP case performed in all centres was entered into an electronic database. Data was extracted from the 1st January 2019 (pre-pandemic) to the 31st December 2021 (post-pandemic). UH was labeled as ‘tertiary unit’ while WH, StX and MH were pooled together and labeled as ‘satellite units’. Results The implementation of three national lockdowns led to a transient decrease in the number of electrophysiology procedures (Figure 1). However, the ‘clean’ patient pathway that we rapidly established at our satellite unit (MH) facilitated the sustained delivery of our cardiac electrophysiology service throughout the pandemic from 2020 to 2021. There were no deaths or differences in complication rates between the 2 units (Table 1). Conclusion Our hub-and-spoke model is a safe and practical system in tackling the AF ablation waiting list even throughout the pandemic.

PO-03-203 NOVEL TRAINING CONCEPT UTILIZING A REAL WORLD LIKE EP SIMULATOR

Training in the field of invasive cardiac electrophysiology (EP) is challenging and requires intellectual skills related to the interpretation of intracardiac electrograms. Classic approach to education of young electrophysiologists focused solely on theoretical knowledge and overseen procedures in patients as no real life like simulation of complete diagnostic and therapeutic EP studies was available. The purpose of this study was to assess a novel tool for EP training based on fully interactive, online simulator providing real clinical experience to the users. EP Simulator replicates EP recording system routinely used in cardiac electrophysiology laboratories and therefore enable easier transition from training to clinical situation. Users are able to access a fully functional system with simulated surface electrocardiogram and intracardiac electrograms mimicking signals recorded by a catheter located at high right atrium, His bundle, coronary sinus, and right ventricular apex. Normal electrophysiology study and the following cardiac arrhythmias are available for simulation: sick sinus syndrome, AV conduction blocks, atrial ectopy, atrial flutter and fibrillation, atrio-ventricular and atrio-ventricular nodal reentrant tachycardia and ventricular tachycardias. Evaluation by 35 electrophysiologists (mean experience 10±6y) from 14 countries was collected via online questionnaire. To every question 5 gradual answers were proposed. Realism of ECG signals was described as excellent or very good by 88% of responders, of intracardial signals by 80%. Realism of signal interactions and user experience was judged as excellent or very good by 75% and 70% accordingly. 100% of users agree definitely or mostly that EP Simulator helps to translate theoretical into practical knowledge. 97% or responders would include it in EP training programs as it is extremely or very useful for training purposes in opinion of 85%. 70% of responders think that training on EP simulator can potentially reduce rate of complications. In 85% the overall experience was completely or mostly satisfying and would be recommended by 100% of responders. Real life like EP simulator is a feasible tool for training of young electrophysiologist. Further systematic evaluation of the training progress is warranted.

Real-time electrophysiological characterization of acute and chronic radiofrequency ablation lesions

Abstract Background Assessment of lesion formation remains one of the most important goals to guide radiofrequency (RF) procedures in the cardiac electrophysiology laboratory. Cardiac navigation systems use specific algorithms to predict the effective lesion size, but these metrics are based only on ablation parameters and ignore local electric tissue characteristics. [1] Recent studies show that local multiparametric impedance is influenced by the intrinsic structural characteristics of the tissue. [2] Purpose This study aimed to assess the ability of local multiparametric impedance to characterize acute and chronic RF ablation lesions in the right atrium of pigs. Methods Four anesthetized closed-chest pigs were submitted to two interventions. The first intervention aimed at creating RF ablation lesions (30W, 60s, 55°) in the right atrium using an electrocatheter connected to a conventional cardiac navigation system, while mapping the local multiparametric impedance (LMI), the generator impedance (GI) and the bipolar voltage (BiV). All RF ablation lesions were performed with a stable contact force. Four weeks later, the second intervention aimed at mapping again the previous ablation sites. After the second intervention animals were euthanized and the hearts were removed and processed to identify the presence of fibrosis in the previously ablated lesions (Figure). Results We performed 19 ablations (5±2 per animal) with an average contact force of 14.2±4.6g. Four weeks later, 14/19 (74%) ablation lesions were identified as fibrotic points in the explanted heart (Figure 1). These showed decreased acute LMI and BiV values that persisted low after 4 weeks (Table 1). The remaining 5/19 ablations that did not present fibrosis had lower baseline LMI and bipolar values that resulted in lower LMI and BiV drops (Table 1). The absolute drop in LMI between effective and non-effective lesions was around 50%, while GI drop was only 21% (LMI drop @51KHz: From −3.0±1.4° to −1.5±0.3°, T-TEST p<0.05; GI drop: From 12.7±27.6Ω to 10.5±21.3Ω, T-TEST p=0.89). Conclusion The local baseline electrical properties of atrial myocardium are directly related to the effectiveness of RF ablation lesions. RF ablation sites that resulted into persistent fibrosis points had larger LMI and BiV values, with higher absolute drops than non-effective lesions. The use of LMI in clinical practice could improve the outcome of the procedures of arrhythmia ablation in the electrophysiology lab. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Supported by grants from ISCI-MINECO (FIS PI21/00392), FEDER, CIBERCV (CB16/11/00276)

Neurocardiac Changes Preceding and During the Onset of Takotsubo Cardiomyopathy in the Cardiac Electrophysiology Laboratory.

Neurocardiac Changes Preceding and During the Onset of Takotsubo Cardiomyopathy in the Cardiac Electrophysiology Laboratory.

A Practical Guide to Ultrasound-guided Venous Access During Implantation of Pacemakers and Defibrillators.

Ultrasound (US) guidance has been shown to be a safe and effective option for gaining access to the axillary vein during implantation of cardiovascular implantable electronic devices (CIEDs). However, US-based technique has not been universally adopted in CIED implantations performed in cardiac electrophysiology (EP) laboratories, despite potential advantages over other vascular access techniques. For this reason, not all cardiac electrophysiologists have been trained to use US guidance during CIED implantation. This review is intended to provide a practical guide to the use of US guidance to obtain axillary vein access in the EP laboratory setting.

The Medical Device Unique Device Identifier as the Single Source of Truth in Healthcare Enterprises – Roadmap for Implementation of the Clinically Integrated Supply Chain

Documentation and tracking of supplies, equipment and medical devices is central to operational, financial, and clinical aspects of safe, efficient, and effective patient care. The labeling of medical devices with a unique device identifier (UDI) creates the opportunity to tightly integrate device information across health information systems by using the UDI as the index “source of truth”. Across 3 hospitals of the Duke University Health System, we executed a comprehensive implementation of UDI-based device and supply information management in our cardiac catheterization and electrophysiology laboratories. Following are our key insights. Implementing a UDI-centric environment is a complex undertaking requiring integration of information systems, management processes, and clinical workflows involving leadership, inventory management, supply chain, clinical and billing teams. Implementation involves the domains of procedure documentation, electronic health records (EHRs), charge capture and billing, and interface and information technology systems, including information systems vendors. Replacing manual processes with electronic messages is not simply an exercise in programming information systems – successful execution requires orchestrated re-engineering of clinical and operational workflows. Our initiative resulted in a more efficient and effective supply chain, eliminated operational and clinical documentation errors, automated the posting of device implant data to the EHR, reduced clinician burden, improved charge capture, and produced a substantial financial benefit, with return on investment recognized in well under 1 year. We believe our stepwise approach to accomplishing a clinically integrated supply chain can serve as a roadmap for other healthcare enterprises to follow.

Electrophysiology and Interventional Cardiology Procedure Volumes During the Coronavirus Disease 2019 Pandemic.

The coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has imposed an unprecedented health care crisis across the globe. Health care efforts across the world have been diverted to tackling the pandemic since early 2020. Hospitals and health care systems have undertaken major restructuring in an effort to deliver health care to an increasing number of patients affected by COVID-19. Although great focus has been placed on treating those individuals suffering from COVID-19, clinicians must simultaneously balance caring for patients who are not actively infected. In anticipation of an exponential increase in COVID-19 cases, health care systems developed strategies to channel available resources to meet the rapidly rising demands of COVID-19. This change was noticed significantly in the field of invasive cardiology as well. Many cardiac catheterization and electrophysiology (EP) laboratories canceled elective procedures to limit the burden on hospital resources and preserve personal protective equipment (PPE). Major societies published guidance statements delineating patient selection for procedures during the exponential phase of the pandemic growth. Patient care was triaged and those waiting for elective procedures were managed with expectant care or noninvasive approaches to preserve hospital resources and personnel. In the current article, we review the impact of the COVID-19 pandemic and its response to the volume of interventional cardiology (IC) and EP procedures across the world.

Conversion of positive‐pressure cardiac catheterization and electrophysiology laboratories to a novel 2‐zone negative‐pressure system during COVID‐19 pandemic

During coronavirus disease‐2019 (COVID‐19) pandemic, there continues to be a need to utilize cardiac catheterization and electrophysiology laboratories for emergent and urgent procedures. Per infection prevention guidelines and hospital codes, catheterization and electrophysiology laboratories are usually built as positive‐pressure ventilation rooms to minimize the infection risk. However, patients with highly transmissible airborne diseases such as COVID‐19 are best caredfor in negative ventilation rooms to minimize the risk of transmission. From a mechanical and engineering perspective, positive‐pressure ventilation rooms cannot be readily converted to negative‐pressure ventilation rooms. In this report, we describe a novel, quick, readily implantable, and resource‐friendly approach on how to secure air quality in catheterization and electrophysiology laboratories by converting a positive‐pressure ventilation room to a two‐zone negative ventilation system to minimize the risk of transmission.

The stationary wavelet transform as an efficient reductor of powerline interference for atrial bipolar electrograms in cardiac electrophysiology

Objective: The most relevant source of signal contamination in the cardiac electrophysiology (EP) laboratory is the ubiquitous powerline interference (PLI). To reduce this perturbation, algorithms including common fixed-bandwidth and adaptive-notch filters have been proposed. Although such methods have proven to add artificial fractionation to intra-atrial electrograms (EGMs), they are still frequently used. However, such morphological alteration can conceal the accurate interpretation of EGMs, specially to evaluate the mechanisms supporting atrial fibrillation (AF), which is the most common cardiac arrhythmia. Given the clinical relevance of AF, a novel algorithm aimed at reducing PLI on highly contaminated bipolar EGMs and, simultaneously, preserving their morphology is proposed. Approach: The method is based on the wavelet shrinkage and has been validated through customized indices on a set of synthesized EGMs to accurately quantify the achieved level of PLI reduction and signal morphology alteration. Visual validation of the algorithm’s performance has also been included for some real EGM excerpts. Main results: The method has outperformed common filtering-based and wavelet-based strategies in the analyzed scenario. Moreover, it possesses advantages such as insensitivity to amplitude and frequency variations in the PLI, and the capability of joint removal of several interferences. Significance: The use of this algorithm in routine cardiac EP studies may enable improved and truthful evaluation of AF mechanisms.

Electrophysiological changes in the conducting properties of fast pathway following modification of the slow pathway of the atrio ventricular node for atrio ventricular nodal re-entrant tachycardia.

Objectives:To determine the possible changes in the conducting properties of the fast pathway after modification of the atrioventricular slow pathway for AVNRT which leads to the failure of the induction of tachycardia.Methods:This study was conducted in the Cardiac electrophysiology Laboratory of Hayatabad Medical Complex, Peshawar, Pakistan from March 2017 to March 2018. All the patients underwent radiofrequency modification of the slow pathway for AVNRT. Patients in whom typical AVNRT was inducible with demonstration of dual AV nodal physiology were included in the study.Results:A total of 171 cases were included in the study, 42 (25%) were males, mean age recorded was 47 ± 15 years. There were no significant changes pre and post ablation in the base line parameters like VV interval, atrioventricular nodal (AV nodal) Wenckebach cycle length, slow pathway effective refractory period (SPERP) or fast and slow pathways maximal Atrio His interval. However significant change was observed in the effective refractory period of the fast pathway 350±49 Vs 290±32 (p value 0.0001). The difference between slow and Fast pathway ERP was also decreased significantly 82±36 Vs 56± 24 (p value 0.004).Conclusion:Our study showed that ablation of AV nodal slow pathway for atrioventricular nodal reentrant tachycardia leads to changes in the effective refractory period of the fast pathway.

Real-world comparison of in-hospital Reveal LINQ insertable cardiac monitor insertion inside and outside of the cardiac catheterization or electrophysiology laboratory

Traditionally, insertable cardiac monitor (ICM) procedures have been performed in the cardiac catheterization (CATH) or electrophysiology (EP) laboratory. The introduction of the miniaturized Reveal LINQ ICM has led to simplified and less invasive procedures, affording hospitals flexibility in planning where these procedures occur without compromising patient safety or outcomes. The present analysis of the ongoing, prospective, observational, multicenter Reveal LINQ Registry sought to provide real-world feasibility and safety data regarding the ICM procedure performed in the CATH/EP lab or operating room and to compare it with insertions performed outside of these traditional hospital settings. Patients included had at least a 30-day period after the procedure to account for any adverse events. We analyzed 1222 patients (58.1% male, age 61.0 ± 17.1 years) enrolled at 18 centers in the US, 17 centers in Middle East/Asia, and 15 centers in Europe. Patients were categorized into 2 cohorts according to the location of the procedure: in-lab (CATH lab, EP lab, or operating room) (n = 820, 67.1%) and out-of-lab (n = 402, 32.9%). Several differences were observed regarding baseline and procedure characteristics. However, no significant differences in the occurrence of procedure-related adverse events (AEs) were found; of 19 ICM/procedure-related AEs reported in 17 patients (1.4%), 11 occurred in the in-lab group (1.3%) and 6 in the out-of-lab group (1.5%) (P = .80). This real-world analysis demonstrates the feasibility of performing Reveal LINQ ICM insertion procedures outside of the traditional hospital settings without increasing the risk of infection or other adverse events.

Occupational and patient radiation doses in a modern cardiac electrophysiology laboratory.

Technological advancements have greatly expanded the field of cardiac electrophysiology, requiring greater demands on imaging systems and potentially delivering higher radiation doses to patients and operators. With little contemporary research on occupational and patient radiation risk in the electrophysiology laboratory, the aim of this study was to analyze radiation doses, including occupational fetal doses, over approximately the last decade. We benchmarked the occupational data to our patient radiation dose data to allow for comparison and to put into perspective the associated radiation risks. Occupational radiation dosimetry analyzed included data from an 11-year period for physicians, a 7-year period for nurses, and a 9-year period for fetal doses. Patient-related dose metrics over an 8-year period were also analyzed. In the physician and nursing groups, there was a nearly 70% decrease in the average occupationalradiation doses over the given periods. Within the electrophysiology department, the average fetal occupationaldoses were very low, close to 0μSv. The average reference point air kerma per patient for all electrophysiology procedures decreased from nearly 600mGy/procedure in 2010 to just over 100mGy/procedure in 2017. Patient and occupational radiation doses in our laboratories significantly decreased over the periods analyzed as a result of clinical and technical staff efforts as well as advances in imaging technology. The radiation-related risk to individuals working in our electrophysiology laboratories, including pregnant women, is very low. Data reported herein could be used by other institutions to evaluate their occupational and patient radiation safety practices.

Prolonged antimicrobial prophylaxis following cardiac device procedures increases preventable harm: insights from the VA CART program.

The rate of cardiovascular implantable electronic device (CIED) infection is increasing coincident with an increase in the number of device procedures. Preprocedural antimicrobial prophylaxis reduces CIED infections; however, there is no evidence that prolonged postprocedural antimicrobials additionally reduce risk. Thus, we sought to quantify the harms associated with this approach. To measure the association between Clostridium difficile infection (CDI), acute kidney injury (AKI) and receipt of prolonged postprocedural antimicrobials. CIED procedures entered into the VA Clinical Assessment Reporting and Tracking Electrophysiology (CART-EP) database during fiscal years 2008-2016 were included. The primary outcome was 90-day incidence of CDI and the secondary outcome was the 7-day incidence of AKI. The primary exposure measure was duration of postprocedural antimicrobial therapy. Associations were measured using Cox-proportional hazards and binomial regression. Prolonged postprocedural antimicrobial therapy was identified following 3,331 of 6,497 CIED procedures (51.3%), and the median duration of prophylaxis was 5 days. Prolonged postprocedural antimicrobial use was associated with increased risk of CDI (hazard ratio [HR], 2.90; 95% confidence interval [CI], 1.54-5.46). Of the 27 patients who developed CDI, 11 subsequently died. Postprocedural antimicrobial use with ≥2 antimicrobials was associated with an increased risk of AKI (OR, 4.16; 95% CI, 2.50-6.90). The impact was particularly significant when one of the dual agents prescribed was vancomycin (adjusted OR, 8.41; 95% CI, 5.53-12.79). Prolonged antimicrobial prophylaxis following CIED procedures increases preventable harm; this practice should be discouraged in procedural settings such as the cardiac electrophysiology laboratory.

Cardiac Invasive Electrophysiology Studies with Radiofrequency Ablation Without Onsite Cardiothoracic Surgical Back-Up in a New Cardiac Electrophysiology Laboratory: Single-Centre Experience

Introduction: Previous studies of invasive cardiac electrophysiology (EP) and radiofrequency catheter ablation (RFA) concluded that procedures can be safely performed successfully in selected groups of patients, by experienced staff, without on-site cardiothoracic surgery back-up. We aim to report a single centre experience.

Supraventricular tachyarrhythmias in patients with a persistent left superior vena cava.

A persistent left superior vena cava (PLSVC) is the most common thoracic venous anomaly. This venous anomaly can impact the evaluation and treatment of supraventricular tachyarrhythmia (SVA). The aim of this study was to assess the proportion and characteristics of PLSVC in adult SVA patients. From July 2002 to July 2012, clinical and procedural data from databases of 10 cardiac electrophysiology laboratories in the Yeungnam region of the Republic of Korea were reviewed. Of 6662 adult SVA patients who underwent an EP study or catheter ablation of SVA during the 10-year study period, 18 patients had PLSVC (mean age 47.6 ± 14.8 years, 10 men). The proportion of PLSVC in adult SVA patients was 0.27% (18/6662). SVA type and procedural outcomes of radiofrequency (RF) catheter ablation in these patients were investigated and the results were as follows: successful slow pathway modification in six of seven patients with atrioventricular nodal reentrant tachycardia (AVNRT), successful ablation of accessory pathway in three of four patients with atrioventricular reentrant tachycardia, and successful ablation of atrial tachycardia (cavotricuspid isthmus-dependent in two, septal macroreentry in one, focal from the PLSVC in one) in three of four patients. In one patient with junctional tachycardia, catheter ablation failed. In two patients with atrial fibrillation, catheter ablation was successful. Among adult SVA patients who underwent an EP study or RF catheter ablation during the 10-year study period, 0.27% had PLSVC. The most common type of SVA was AVNRT. The success rate of catheter ablation was 82% in SVA patients with PLSVC. There were no procedure-related complications.