Cardiac Implantable Devices Research Articles

Impact of the Covid19 pandemic on implantable cardiac device implants in Spain. Data from the nationwide Covid 19 RM (remote monitoring) Spain registry

Abstract Funding Acknowledgements Type of funding sources: None. Background The Covid-19 pandemic has meant a very significant reduction in all urgent and non-urgent activity, including the implants of Cardiac Implantable electronic devices (CIEDs) throughout 2020. From the end of 2020 and throughout the year 2021, hospital activity has normalised, but it is uncertain whether the devices that were not implanted within 2020 have been delayed in time or actually lost. Purpose We sought to evaluate the pre and post-pandemic trends in CIEDs implantations from a large nationwide database in order to determine the global effect of the COVID-19 pandemic on CIEDs implants in Spain. Methods The Covid-19 Remote Monitoring Spain Registry (Covid-19 RM-Spain) is a survey supported by the Heart Rhythm Association of the Spanish Society of Cardiology to request the whole national data regarding the number of CIED´s implants and remote monitoring activations from the five main manufacturers classified according to each autonomous community (not by institutions).All data were aggregated and anonymized to analyse the total sample. Appropriate permissions were granted to use the data and a confidentiality agreement was signed in order to avoid any transmission of sensitive information. Results No institution objected to the use of their data, so the total number of devices implanted in Spain were obtained, which were 50258, 52994, 47330 and 54490 in 2018, 2019, 2020 and 2021 respectively. When we try to balance the drop in implants during 2020 and the subsequent increase experienced during 2021 against the average of 2018 and 2019, we have observed that approximately 2600 pacemakers (7%) and about 150 defibrillators (3.1%) have been "lost". With regard to the rest of the devices, adding up the differences between 2020 and 2021 and comparing them with the average for 2018-19, an increase of 419 Cardiac Resynchronization defibrillators (18%), 130 Cardiac Resynchronization Pacemakers (9.4%) and 1189 Implantable Loop recorders ( 26%) have been observed. Conclusion(s) In 2020 there was a large reduction in all CIEDs implants. In the most numerous devices (pacemakers), unlike the rest, the increment has not compensated for the reduction in implants that occurred in 2020 by the end of 2021. The marked increase in the number of cardiac resynchronization implants may suggest that the indication for single or dual-chamber defibrillator implantation may have finally evolved in a significant number of patients into an indication for cardiac resynchronization. Abbreviations: CRT-D: Cardiac resynchronization Therapy -Desfibrillator; CRT-P: Cardiac resynchronization Therapy -pacemaker; ICD: Implantable cardiac defibrillators; ILR: Implantable Loop recorders; LLPM: Leadles Pacemakers; PM: Pacemakers; S-ICD: Subcutaneous Implantable cardiac defibrillator.

Covid 19 pandemic: the final boost for remote monitoring of implantable cardiac devices? : analysis from the nationwide remote monitoring registry (Covid-19 rm-spain)

Abstract Funding Acknowledgements Type of funding sources: None. Background Remote monitoring of implantable cardiac devices (CIEDs) has proven to be reliable, more efficient and even safer than conventional in-office follow-ups However, its implementation has not been as desired. The COVID 19 pandemic and the need to keep patients away from hospitals may have been the final boost for this form of monitoring. Purpose We sought to evaluate the pre and post-pandemic trends in CIEDs remote monitoring activations from a large nationwide database in order to determine the global effect of the COVID-19 pandemic on CIEDs implants in Spain. Methods The Covid-19 Remote Monitoring Spain Registry (Covid-19 RM-Spain) is a survey supported by the Heart Rhythm Association of the Spanish Society of Cardiology to request the whole national data, regarding the number of CIED´s implants and remote monitoring activations from the five main manufacturers classified according to each autonomous community (not by institutions).All data were aggregated and anonymized to analyse the total sample. Appropriate permissions were granted to use the data and a confidentiality agreement was signed in order to avoid any transmission of sensitive information. Results The percentage of devices for which remote monitoring was activated was 24.5%; 28.4%, 42% and 49% in 2018, 2019 ,2020 and 2021, which implies that remote monitoring is now activated on more than twice as many devices in Spain as in 2018. The table shows the differences in the percentages of remote monitoring activation between three different periods for each type of device. (Period 1 /pre-lockdown January 2018-February 2021; Period 2/ lockdown: March-June 2020 and Period 3/ lockdown: July 2020-December 2021. Footnotes: Period A vs. B p<0,001 :1 ; Period A vs. C p<0,001:2; Period B vs. C p<0,001:3 Abbreviations : CRT-D: Cardiac resynchronization Therapy -Desfibrillator; CRT-P: Cardiac resynchronization Therapy -pacemaker; ICD: Implantable cardiac defibrillators; ILR: Implantable Loop recorders; LLPM: Leadles Pacemakers; PM: Pacemakers; S-ICD: Subcutaneous Implantable cardiac defibrillator.

Temporary trends of cardiac device related infective endocarditis in a tertiary referral center between 2006 and 2022

Abstract Funding Acknowledgements Type of funding sources: None. Background Infective endocarditis (IE) is a rare, but life-threatening complication of cardiac device implantation. Despite recent preventive strategies and advances in antimicrobial and surgical treatment, morbidity and mortality rates are still high. Aims The objective of our study was to assess the epidemiological characteristics, temporal trends and mortality rates of cardiac device related IE (CDRIE) in our high-volume, tertiary referral center. Methods retrospective data collection was performed between January 1, 2006 and March 31, 2022. Median follow-up was 3.8 yrs (IQR: 0.6 – 9.2 yrs). Patients admitted between 2006 and 2013 (group 1) and between 2014 and 2022 (group 2) were compared to assess temporal trends. Thirty-day, 6-month and 1-year mortality rates were estimated. Results During the observed 17 years 82 patients were admitted with CDRIE (61 males [74%]), mean age: 57.3 ±18 yrs; 6 VVI, 7 VDD, 17 VVI-ICD, 24 DDD, 10 DDD-ICD and 18 CRT devices [4 CRT-P, 14 CRT-D]); median time since first implantation was 3.8 yrs [IQR: 1.1 – 6.6 yrs]). Staphylococci were the most prevalent infective agents (62%), S. aureus (SA) infection was found in 37 cases (out of whom 13 were MRSA [16%]), coagulase negative Staphylococcus in 14 cases (17%), Enterococcus faecalis in 9 cases (11%), streptococci in 4 cases (5%), blood culture was negative in 13 cases (15%), and in 5 cases other pathogens were the underlying microorganism. Patients in Group 1 (n=42) did not differ from patients in Group 2 (n=40) in terms of age, male gender or ejection fraction. Patients in Group 2 had higher CRP level at admission (42,9 [IQR:34-55] mmol/l vs 90 [IQR:25-60] mmol/l, p=0.02). ICD lead (29% vs 67%, p<0.001) and E. faecalis infection (2% vs 20%, p=0.03) and percutan extraction (55% vs 75%, p=0.05) were more prevalent in Group 2. The 30-day and 6-month mortality rates were worse in Group 2 than in Group 1 (2% vs 17.5% p=0.03; and 16% vs 35% p=0.04 resp.) while the 1-year mortality did not differ (24% vs 40%). The all-cause mortality was 10% at 30 days, 26% at 6 month and 32% at 1 year. Univariate regression showed that age (HR: 1.03 [1.01-1.07] p<0.05), ejection fraction (HR: 0.96 [0.93-0.98] p<0.005), ICD lead (HR: 4.89 [1.82-14.40] p<0.005) and the time since first implantation (HR: 0.88 [0.77-0.98] p<0.05) were the predictors of 1-year mortality. However, in Cox multiple regression model only age (HR: 1.05 [1.004-1.1] p<0.05) and ICD lead (HR: 1.16 [1.16-17.38] p<0.05) remains independent predictors of outcome at 1 year. Conclusions In the past 17 years the most prevalent underlying microorganism were staphylococcal species, although Enterococcus faecalis infection increased over time. Patients with CDRIE had poor prognosis, every third patient died at 1 year after diagnosis. The short-term prognosis is even worse in the past few years than before, which may be a negative consequence of limited accessibility of healthcare due to COVID 19 pandemic.

Appropriate and inappropriate therapies in remotely monitored patients with cardiac implantable devices long-term experiences of a tertiary centre

Abstract Funding Acknowledgements Type of funding sources: None. Background The evidence supporting the implantation of implantable cardioverter-defibrillator (ICD) in the primary prevention of sudden cardiac death (SCD) comes mostly from the times when optimal management of heart failure was not as effective as at present. Moreover, the detailed data on the long-term risk of arrhythmias in patients with ICD are scarce. Purpose To present the long-term results of the remote monitoring (RM) of patients with ICD from a large, tertiary cardiovascular centre registry. Methods The clinical data from the time of device implantation were derived from the COMMIT-HF registry, while the follow-up data were obtained from the investigator-initiated RM registry. In brief, the registry encompasses data regarding the types of the transmissions and their contents, with particular emphasis on the occurrence of arrhythmic episodes, device interventions, as well as the data on the causes of other alert transmissions. Results In total, 1,299 patients were included in the analysis. The median follow-up duration of RM was 4.4 years, and the primary indication for implantation was ischemic cardiomyopathy (60.3%). Appropriate antitachycardia pacing (ATP) and high-voltage therapy for ventricular arrhythmias occurred in respectively 25.3% and 26.1% of patients, while inappropriate ATP and HV in respectively 11.5% and 8.7%. The prevalence of AF was 40.8%. Conclusions In a large real-life cohort of continuously remotely monitored patients with ICDs, the percentage of patients with appropriate therapies for ventricular arrhythmias exceeded 25%. Further analyses are necessary to stratify the risk of ventricular arrhythmias in the contemporary practice.

P462 ATRIAL FIBRILLATION CIED DETECTED; WHEN TO SCOAGULATE? OUR EXPERIENCE ON A STILL VERY CONTROVERSIAL TOPIC

Abstract Introduction Atrial fibrillation (AF), which is constantly increasing in the population, is associated with an important care burden linked, in particular, to its consequences (stroke, heart failure, etc.). In patients with an implantable cardiac device (CIED) it is frequent the detection of high atrial frequency episodes (AHRE), often asymptomatic, for which an increased thromboembolic risk has been described (about 2.5 times) but lower than the clinical AF for which there is still no unanimous consensus regarding the initiation of oral anticoagulant therapy (OAT). We report below our experience in patients undergoing CIED implantation in whom AHRE was detected and OAT started, evaluating the characteristics of thromboembolic risk and the follow–up of complications. Methods From 01 January 2020 to 31 December 2021, 242 patients (mean age 74.8 years) underwent CIED implant. Among these, 41 patients (16.9% mean age 78.6 years – 30 males and 11 females) presented episodes of AHRE, detected by remote monitoring, lasting between a few seconds and more than 24 hours. The mean CHADsVasc score of these patients was 3.8. Seven patients were not anticoagulated due to arrhythmic episodes lasting a few minutes and CHADsVasc score equal to 1–2, while the other 34 started OAT with DOAC. Results No thromboembolic events or major bleeding events have been recorded to date; only minor bleedings (11 epistaxis, 4 haematuria and 5 SOF positivity) were easily treated. Conclusions The current guidelines indicate to prolong monitoring until the detection of clinical AF or an arrhythmic burden > 24 hours before considering OAT; however, there are studies that recommend carefully correlating the duration of arrhythmic events with the determination of the thromboembolic risk. In our experience, the high thromboembolic risk of patients, sometimes not adequately represented by the CHADsVasc score, led us to start OAT even when the duration of the episodes was not particularly long and at the moment no major complications have been observed. The two ongoing trials (ARTESia and NOAH) dedicated to the evaluation of these situations will provide valuable indications on the treatment of these patients in whom the thromboembolic risk is certainly lower than that of patients with clinical AF but still not negligible.

P467 CHALLENGING MANAGEMENT OF ORAL ANTICOAGULANT THERAPY IN A OBESE PATIENT WITH DILATED CARDIOMYOPATHY, ATRIAL FIBRILLATION AND ICD LEAD THROMBUS

Abstract Obesity is a worldwide epidemic condition at high risk for AF development; nevertheless, obese patients are underrepresented in RCTs of anticoagulant agents. Robust evidence assessing efficacy of DOACs in these patients is lacking and, to date, major Associations do not recommend DOACs in patients > 120 Kg (BMI>40 Kg/m2). The use of implantable cardiac devices has substantially increased in recent years; among potential complications are sterile intracardiac clots on the leads, typically discovered as incidental echocardiographic findings. 46 ys old male patient, III degree obesity (160 Kg,BMI 51 Kg/m2), ex–smoker. In 2012, acute heart failure and diagnosis of non–ischemic dilated cardiomyopathy (EF 20%). During the follow–up by a tertiary Center, in 2021 he was implanted with single–chamber ICD in primary prevention. At presentation, HFrEF pharmacological therapy was optimal (ARNI,SLGT2i,MRA,B–blocker). He came to the ED complaining of weakness; ECG showed atrial fibrillation, mean ventricular rate 160 bpm. CHA2DS2–VASc was 1. Anticoagulation with subcutaneous enoxaparin 10000UI twice daily was started. He was admitted to the cardiology ward and remained hemodynamically stable, with persistence of AF. Transesophageal echocardiography excluded thrombus in the left atrial appendage; unexpectedly, a filamentous, floating formation of about 30mm on the atrial side of the ICD lead was observed, compatible with a thrombotic formation, since the patient, afebrile, didn’t show any suggestive sign of endocarditis nor past history of infection; blood cultures, CRP and Procalcitonin were negative. In the absence of any shunt at the level of interatrial septum, it was felt safe to proceed to electrical cardioversion, able to restore sinus rhythm with a single 250J biphasic synchronized shock. Oral anticoagulation with warfarin was started, since no DOAC was considered adequate for effective anticoagulation. The following in hospital course and post–discharge weeks were uneventful, despite unstable INR values. Follow–up is ongoing; the patient has not yet repeated imaging to check for mass resolution. Stroke prevention in severely obese patients with AF is challenging and points toward warfarin use, as the evidence of DOACs efficacy is sparse. In our case, anticoagulant choice was also motivated by concomitant presence of a lead thrombus, a scenario in which optimal management and anticoagulation regimen are not clearly established yet.

LB-456091-4 LOW ENERGY MULTI-PULSE THERAPY FOR CARDIOVERSION OF AF IN HUMANS

Early rhythm control improves clinical outcomes in atrial fibrillation (AF) patients (pts). Incorporation of atrial shocks for cardioversion of AF via cardiac implantable devices (CIEDs) has had good efficacy but limited uptake due to pain perception. Multi-pulse Therapy (MPT) has a unique waveform sequence with three stages that could have similar cardioversion success at tolerable energies. A prospective, non-randomized feasibility study involved acute testing to assess safety and efficacy of MPT in AF.

Antithrombotic management in patients undergoing cardiac implantable electronic device implantation

Cardiac implantable electronic devices (CIEDs) are an established treatment option for arrhythmias, sudden cardiac death prevention, and heart failure. Approximately 1000 devices are implanted per million inhabitants in European countries each year. However, the main concern in patients with an indication for CIED implantation is frequently associated with comorbidities requiring antithrombotic medications. The invasive device implantation procedure represents a bleeding risk ranging from pocket hematoma to cardiac tamponade. On the other hand, temporary interruption of antithrombotic therapy increases the risk for thromboembolic events. Implanting CIEDs in patients on antithrombotic medications incites several clinical dilemmas of balancing thromboembolic risk against bleeding risk, as complications are associated with higher mortality rates in both aspects. The most common bleeding complication is pocket haematoma formation, which is associated with a prolonged hospital stay, higher cost, higher risk of pocket infection, and thus higher morbidity and mortality. Studies have shown that the heparin bridging strategy in patients on oral anticoagulants imposes a greater risk for pocket haematoma formation and no benefit in reducing thromboembolic events. Most procedures of CIED implantation can be performed safely with uninterrupted oral anticoagulants. Dual antiplatelet therapy increases the risk of pocket haematoma and should be avoided whenever possible.

Reduced Left Atrial Appendage Flow Is Associated With Future Atrial Fibrillation After Cryptogenic Stroke

Hemostasis within the left atrial appendage (LAA) is a common cause of stroke, especially in patients with atrial fibrillation (AF). Although LAA flow provides insights into LAA function, its potential for predicting AF has yet to be established. The aim of this study was to explore whether LAA peak flow velocities early after cryptogenic stroke are associated with future AF on prolonged rhythm monitoring. A total of 110 patients with cryptogenic stroke were consecutively enrolled and underwent LAA pulsed-wave Doppler flow assessment using transesophageal echocardiography within the early poststroke period. Velocity measurements were analyzed offline by an investigator blinded to the results. Prolonged rhythm monitoring was conducted on all participants via 7-day Holter and implantable cardiac monitoring devices, with follow-up conducted over a period of 1.5years to determine the incidence of AF. The end point of AF was defined as irregular supraventricular rhythm with variable RR interval and no detectable P waves lasting ≥30sec during rhythm monitoring. During a median follow-up period of 539 days (interquartile range, 169-857 days), 42 patients (38%) developed AF, with a median time to AF diagnosis of 94 days (interquartile range, 51-487 days). Both LAA filling velocity and LAA emptying velocity (LAAev) were lower in patients with AF (44.3±14.2 and 50.7± 13.3cm/s, respectively) compared with patients without AF (59.8±14.0 and 76.8±17.3cm/sec, respectively; P<.001 for both). LAAev was most strongly associated with future AF, with an area under the receiver operating characteristic curve of 0.88 and an optimal cutoff value of 55cm/sec. Age and mitral regurgitation were independent determinants of reduced LAAev. Impaired LAA peak flow velocities (LAAev<55cm/sec) in patients with cryptogenic stroke are associated with future AF. This may facilitate the selection of appropriate candidates for prolonged rhythm monitoring to improve its diagnostic accuracy and implementation.

Risk Factors for Infections of Cardiac Implantable Electronic Device in Saudi Arabia

Background and Objectives: Cardiac implantable electronic device (CIED) infections are increasing worldwide due to the increased use of implantable cardiac devices. (CIED) infection is a serious complication that is associated with increased mortality and morbidity as well as increased healthcare costs. However, risk factors for infection of implanted devices are poorly documented in Saudi Arabia. We aimed to determine risk factors for CIED infection in our region. Methods and Results: A retrospective study was carried out in cardiology departments at different centers in Saudi Arabia. Our population consisted of all patients with device-related infections over twenty years from January 2009 to December 2020 with one control case matched to each confirmed infection of the implanted device, resulting in 137 patients with device infection. The mean age was 58±16 years, where males constituted 75.2%. Most infections occurred in patients with the first implant. (63.5%) patients had chronic kidney disease, (59.9%) of patients had diabetes mellitus, (65%) of patients had hypertension, and (43.1%) of patients had coronary artery disease. Most of the patients had a pocket infection. Preop antibiotics were obtained in all patients before implanting. The median time from the last surgical intervention involving the device to infection symptoms was 730 days. The median length of hospitalization was 27±23 days. 130 patients survived at the time of discharge, resulting in an overall mortality rate of 5.1%. Using Multivariate analysis, we identified male gender (P = 0.000), hypertension HTN (P = 0.002), diabetes DM (P = 0.006), and presence of underlying heart disease CHD (P = 0.000) Type of the device (P = 0.000) as significantly associated with a higher risk of CIED infection. Conclusion: Our data show that gender, diabetes, hypertension, and heart disease are independent risk factors for infection after cardiac device implantation. As regards device characteristics, ICD device is associated with a higher infection rate compared to other devices.

Regional beat-to-beat variability of repolarization increases during ischemia and predicts imminent arrhythmias in a pig model of myocardial infarction.

Ventricular arrhythmia (VT/VF) can complicate acute myocardial ischemia (AMI). Regional instability of repolarization during AMI contributes to the substrate for VT/VF. Beat-to-beat variability of repolarization (BVR), a measure of repolarization lability increases during AMI. We hypothesized that its surge precedes VT/VF. We studied the spatial and temporal changes in BVR in relation to VT/VF during AMI. In 24 pigs, BVR was quantified on 12-lead electrocardiogram recorded at a sampling rate of 1 kHz. AMI was induced in 16 pigs by percutaneous coronary artery occlusion (MI), whereas 8 underwent sham operation (sham). Changes in BVR were assessed at 5 min after occlusion, 5 and 1 min pre-VF in animals that developed VF, and matched time points in pigs without VF. Serum troponin and ST deviation were measured. After 1 mo, magnetic resonance imaging and VT induction by programmed electrical stimulation were performed. During AMI, BVR increased significantly in inferior-lateral leads correlating with ST deviation and troponin increase. BVR was maximal 1 min pre-VF (3.78 ± 1.36 vs. 5 min pre-VF, 1.67 ± 1.56, P < 0.0001). After 1 mo, BVR was higher in MI than in sham and correlated with the infarct size (1.43 ± 0.50 vs. 0.57 ± 0.30, P = 0.009). VT was inducible in all MI animals and the ease of induction correlated with BVR. BVR increased during AMI and temporal BVR changes predicted imminent VT/VF, supporting a possible role in monitoring and early warning systems. BVR correlated to arrhythmia vulnerability suggesting utility in risk stratification post-AMI.NEW & NOTEWORTHY The key finding of this study is that BVR increases during AMI and surges before ventricular arrhythmia onset. This suggests that monitoring BVR may be useful for monitoring the risk of VF during and after AMI in the coronary care unit settings. Beyond this, monitoring BVR may have value in cardiac implantable devices or wearables.

CI-452764-2 HIGH-POWER CHARGERS FOR ELECTRIC VEHICLES: ARE THEY SAFE FOR PATIENTS WITH PACEMAKERS AND DEFIBRILLATORS?

Electromagnetic interference (EMI) poses a risk to patients with cardiac implantable devices (CIEDs) and can result in device malfunction including pacing inhibition or inappropriate shock therapy. Such EMI sources are ubiquitous in the modern world. Battery electric vehicles (BEVs) represent such a potential EMI source. We have previously investigated the EMI risk of driving eCars and found that the largest electromagnetic field is located along the charging cable. New high power chargers deliver higher currents (facilitating rapid recharging), potentially associated with greater electromagnetic fields and higher risk for clinically relevant EMI. This present study aims to evaluate this EMI-risk for CIED patients while using high-power chargers for electric vehicle A consecutive group of 130 patients with a range of CIEDs were recruited to participate. After a complete device interrogation each had their device programmed to optimise EMI detection with ensured ventricular pacing and ICD therapies were disabled. Under continuous 6-lead ECG monitoring each patient then plugged in and charged four different BEVs (Porsche Taycan Turbo, VW ID3 pro, Tesla Model 3 and Audi e-tron 55 Quattro) in addition to a ‘dummy’ eCar (which permitted the maximal charging power flow of 350kW) with the charging cable placed directly over the device (Figure 1). During charging both the magnetic field and electric field was measured. A further complete device interrogation was then performed to evaluate for spontaneous reprogramming and tachycardia detection. In total 561 separate charging events were performed by 130 patients with the four eCars and one dummy car. There were no incidences of EMI, specifically there was no pacing inhibition due to oversensing, no spontaneous reprogramming and no tachycardia over-detection. This results in a patient-based risk of 0% (95% CI; 0% - 2.8%) and a charging event-based risk of 0% (95% CI; 0% - 0.6%). The use of electric cars with high-power chargers by patients with cardiac devices appears to be safe with no evidence of clinically relevant EMI. Reasonable caution, by minimising the time spent in close proximity with the charging cables, is still advised as the occurrence of very rare events cannot be excluded from our results.

PO-04-223 ASSOCIATION BETWEEN ANTIPARASITIC TREATMENT AND VENTRICULAR ARRYTHMIAS IN PATIENTS WITH CHAGAS DISEASE

Benznidazole and Nifurtimox are the two currently available antiparasitic treatments available for Chagas disease (CD), an important cause of cardiomyopathy and arrhythmias. There are limited data available describing impact of antiparasitic treatment on arrhythmia outcomes. Compare the incidence of ventricular arrhythmias in Chagas patients treated with anti-parasitic medication versus those who did not receive treatment. Patients treated at a Chagas disease center of excellence were retrospectively analyzed for ambulatory rhythm monitoring data (Holter and 14-day patch monitor). Patients with implantable cardiac devices were excluded. Significant ventricular arrhythmias were defined as either a PVC burden >/=1% or non-sustained ventricular tachycardia (NSVT) ≥4 beats. Patients were analyzed based on CD treatment: Benznidazole, Nifurtimox, or no treatment. Patients with incomplete treatment courses were excluded from analysis. A Fisher exact test was used to compare categorical variables. There were 191 patients with CD between 12/2014 and 8/2022 available for analysis, of whom 66 patients underwent ambulatory rhythm monitoring. Of these, 20 were male and 46 were female with an average age of 55.3 ± 12.6 years, and ejection fraction of 56.7 ± 10.5%. Of the 66 patients, 42 (63.6%) received treatment, 22 (33.3%) had no treatment, and 2 (3.0%) received incomplete treatment for CD. Among patients that received treatment for CD, 11/42 (26.2%) had significant ventricular arrhythmias on ambulatory rhythm monitoring. In comparison, among patients who did not receive CD treatment, 12/22 (54.5%) had significant ventricular arrhythmias (p = 0.031). No significant difference in the number of ventricular arrhythmias was observed between the Benznidazole (7/29, 24.1%) and Nifurtimox (4/12, 33.3%) treatment groups. These data demonstrate that treatment of CD is associated with a reduction in ventricular arrhythmias on ambulatory rhythm monitoring. Further studies are needed to determine if CD treatment can lead to reduced incidence of sudden death.

Cardiac resynchronization therapy device implantation using suspended personal radiation protection system: Examination of radiation protection effectiveness by dosimetry at 51 exposure sites.

Cardiologists often use fluoroscopic equipment for treatment such as cardiac implantable electronic device implantation, catheter ablation, percutaneous coronary intervention, and other procedures. Difficulties arise in protecting the head and optical lens from the exposure of radiation, which is a significant concern among physicians1,2. Currently available radiation protective clothing consists of a collar for the thyroid gland and a sleeveless apron. Although higher radiation protection can be expected by increasing the lead content of the protective clothing, there is a limit to additional lead content due to the increased weight.

PO-05-011 IMMUNOSUPPRESSIVE THERAPY WAS ASSOCIATED WITH LEAD DISLODGEMENT AFTER CARDIAC IMPLANTABLE ELECTRONIC DEVICE IMPLANTATION

Lead dislodgement is one of the severe complications in cardiac implantable electronic device (CIED) implantation. After CIED implantation, adhesions are formed between leads and tissues by inflammation, and as a result, leads are fixed in vessels. In patients with immunosuppressive therapy, such as steroids or immunosuppressant usage, adhesion is inhibited by anti-inflammatory effects. However, no studies have investigated the association between lead dislodgement and immunosuppressive therapy. We hypothesized that lead dislodgement more frequently occurs in patients with immunosuppressive therapy than those without. The purpose of this study was to investigate the association between lead dislodgement and immunosuppressive therapy. In total, 632 consecutive patients who underwent initial CIED implantation or lead addition (age, 76 ± 11 years; male, 365 [58%], high voltage device, 106 [17%], lead addition, 18 [3%]) were retrospectively enrolled. Lead placement was guided by fluoroscopy, and active fixation leads were used in all patients. Chest tape were removed at 1 week after the procedure. Lead dislodgement was defined as a change in the lead position requiring reoperation. As immunosuppressive therapy, 14 (2%) patients used steroids regularly, and 7 (1.1%) used immunosuppressant. Lead dislodgement occurred in 9 (1.4%) patients. Lead dislodgement more frequently occurred in patients with steroids usage than those without (7 (1%) versus 2 (14%), p<0.001). Similarly, lead dislodgement more frequently occurred in patients with immunosuppressant usage than those without (7 (1%) vs 2 (28%), p<0.001). In patients with CIED implantation or lead addition, lead dislodgement more frequently occurred in patients with steroids usage or immunosuppressant usage than those without.

CI-452765-3 INFECTION VERSUS NON-INFECTION INDICATION FOR LEAD EXTRACTION IN THE RELEASE COHORT

Patients with infected cardiac electronic implantable devices (CIEDs) often undergo transvenous lead extraction (TLE) to achieve infection control. The risk of adverse outcomes in this population is high and not well characterized. We sought to compare population demographics and outcomes between the infection and non-infection lead extraction subgroups of the RELEASE cohort, a prospective registry of patients undergoing TLE using mechanical rotating sheaths. The RELEASE cohort was assembled from 10 sites across the United States and Europe. Population demographics, clinical success, complete lead removal, and device-related major complications were reported over a follow-up period of 4 weeks post-procedure. Patients undergoing TLE with infection versus non-infection indication were compared. 230 patients were included in this analysis. The mean age was 64.3±14.4 years, with 67.4% male, and a mean body-mass index of 29.6±6.7 kg/m2. Patients had LV dysfunction (32.2%, EF<35%), coronary artery disease (52.6%), cardiomyopathy (56.1%), diabetes (29.6%), hypertension (67.4%), and renal failure (28.3%). The mean number of leads extracted was 2.0±0.9 leads, with a mean indwell time of 113.8±75.3 months, with implantable cardioverter-defibrillators accounting for 38.3% of patients (88/230). No deaths occurred at time of extraction. 8 deaths (3.5%) occurred during the follow-up period. Demographics and outcomes are reported in Table 1. Patients with infection indication for TLE were generally older (p=0.025), more often male (p=0.032), had more renal failure (p<0.001), and more leads in situ (mean 2.4±0.9 versus 1.8±0.9 leads, p<0.001). There were similar rates of complete lead removal (p=0.91), but more deaths after TLE for infection indication compared to non-infection indication (9.5% vs. 0.6%, p<0.001). Infection indication was not associated with higher likelihood of complete lead removal. In multivariable analysis, renal failure and infection were associated with death (renal failure: OR 10.4, 95% CI 1.17-91.8, p=0.036; infection: OR 7.73, 95% CI 0.87-68.7, p=0.067). Compared to patients undergoing TLE for non-infection indication, patients with infection had more comorbidities and eight times higher odds of death during follow-up. Both infectious indication and renal failure were independent predictors of death. The high risk of morbidity in this patient population should be considered prior to TLE.Summary of Baseline Demographics and Outcomes between Infection and Non-Infection Indication Subgroups from the RELEASE StudyVariableNon-Infection Indication (n=156)Infection Indication (n=74)p-valueDemographicsAge, mean±SD62.8±14.767.4±13.00.025Male sex62.8%77.0%0.032BMI, mean±SD29.5±6.929.9±6.20.68EF<35%30.8%35.1%0.51Coronary artery disease48.7%60.8%0.086Cardiomyopathy59.6%48.6%0.12Diabetes26.9%35.1%0.20Hypertension67.3%67.6%0.97Renal failure17.3%51.4%<0.001Device InformationNumber of Leads, mean±SD1.8±0.92.4±0.9<0.001Indwell time in months, mean±SD117.8±70.8105.5±83.8<0.001ICD35.9%43.2%0.28Lead Extraction OutcomesSuperior Approach Only84.6%91.9%0.13Complete Lead Removal94.2%94.6%0.91ComplicationsDevice-Related Major Complications4.5%8.1%0.27Vascular Avulsion or Tear0.6%1.4%0.59Cardiac Avulsion or Tear0.6%1.4%0.59Bleeding requiring Treatment0.6%5.4%0.021Death0.6%9.5%<0.001Days to Death, mean±SD1520.4±14.80.74Days to Discharge, mean±SD2.9±10.18.5±10.6<0.001EF=ejection fraction; ICD=implantable cardioverter-defibrillator; SD=standard deviation Open table in a new tab

PO-04-069 OUTCOME AND SAFETY OF PULSED FIELD ABLATION FOR ATRIAL FIBRILLATION

Pulsed field ablation (PFA) has recently been introduced as a novel ablation technology for atrial fibrillation (AF). However, data on long-term procedural outcome are sparse. To investigate acute and chronic procedural success and safety in patients undergoing PFA for the treatment of AF. Consecutive paroxysmal and persistent AF patients underwent PFA-based catheter ablation using a multi-spline catheter. PFA-based ablation procedures, including first and repeat ablation procedures, were performed with additional 3D electroanatomical mapping. Procedural parameters, acute success, safety and long-term outcome were assessed. Follow up was conducted by telephone interview, routine Holter-ECGs and control of implantable cardiac devices, if applicable. A total of 101 patients undergoing PFA from May 2021 until November 2022 in one German center were included in the study. Patients suffered from paroxysmal AF (n= 38; 38%), persistent AF (n=36; 36%) and consecutive atrial tachycardias (AT) due to previous catheter ablation (n=27; 26%). Mean age was 67 ± 14 years, median CHA2DS2-VASc Score was 2 (Q1-Q3: 1-3), mean left atrial diameter was 44 ± 9 mm and 83 of 101 (82%) patients had a normal left ventricular ejection fraction. Of all PFA procedures, 61 (60%) were index ablation procedures and 40 (40%) were repeat procedures (including re-pulmonary vein isolation and/or left posterior wall isolation and/or conduction of roof, anterior and/or mitral isthmus lines). The median total procedure and left atrial (LA) PFA times were 98 (Q1-Q3: 61-121) and 34 (Q1-Q3: 24-47) minutes, respectively. Mean total fluoroscopy and LA PFA fluoroscopy times were 14 ± 7 and 9 ± 5 minutes. Successful PFA lesions were created in 100/101 patients (99%). In one patient, the use of radiofrequency ablation in the coronary sinus was needed to block the mitral isthmus line. Total complication rate was 7.9% (8/101) including only one major complication (n=1 pericardial tamponade; 0,99%). Minor complications were found in 7 patients (1 coronary spasm without sequela, 2 minor groin AV fistulas, 1 cardiac decompensation, 1 transient intra-procedural AV-block, 1 aspiration, 1 macro hematuria). Preliminary follow up of 264 ± 138 days including 63 patients showed 83% freedom from arrhythmias (52/63 patients without recurrence). In this initial experience, PFA applied in patients with atrial fibrillation demonstrates high chronic procedural success rates and a favorable safety profile.

PO-04-099 OUTCOME AFTER PULSED FIELD ABLATION IN PATIENTS WITH COMPLEX CONSECUTIVE ATRIAL TACHYCARDIA IN CONJUNCTION WITH ULTRA-HIGH DENSITY MAPPING

Catheter-ablation (CA) of consecutive left atrial tachycardias (LAT) can be challenging. Pulsed field ablation (PFA) yields a novel non-thermal CA technology for treatment of atrial fibrillation (AF). There is no data regarding PFA of LAT. This study sought to investigate the outcome of PFA in consecutive LAT following prior CA of AF. Consecutive patients with LAT underwent ultra-high-density (UHDx) mapping. Subsequent to identification of the AT mechanism, PFA was performed at the assumed critical sites for LAT maintenance. Continuous ablation lines were performed if required and evaluated with pre- and post PFA HDx-mapping. Follow up was conducted by telephone interview, routine 24hrs Holter-ECGs and control of implantable cardiac devices, if applicable. Fifteen patients (age 70±10, male 73%) who underwent 3±2 prior AF-CA procedures were included. The total mean procedure and fluoroscopy times were 141±43 and 18±10 minutes, respectively. All 19 of 19 (100%) LAT were successfully ablated with PFA. Two AT located at the right atria required RF-ablation. LAT were identified as localized reentry (n=1) and macro-reentry LAT (n=18) and targeted with PFA. All LAT terminated with PFA either to sinus rhythm (9/15) or a secondary AT (6/15 and subsequently to SR); 63% (12/19) terminated with the first PFA-application. All lines (13 roof, 11 anterior, 1 mitral) were blocked. LA-posterior-wall isolation (LAPWI) was successfully achieved when performed (10/10). Preliminary AF/AT free survival was 80% (12/15) after 153 [88-207] days of follow-up. No procedure related complications occurred. PFA of consecutive LAT is feasible and safe with a promising outcome. Successful creation of ablation lines and LAPWI can be achieved in a short time. PFA may offer the opportunity for effective ablation of atrial arrhythmias beyond AF.

PO-04-075 TRANSVENOUS CARDIAC DEFIBRILLATOR WITHOUT INTERACTION WITH THE MAGNETIC TITANIUM BEADS SYSTEM FOR GASTROESOPHAGEAL REFLUX DISEASE

Gastroesophageal reflux is increasingly treated with LINX®, a flexible bracelet of magnetic titanium beads (not MRI compatible) that is laparoscopically implanted to wrap around the gastroesophageal junction for providing tone/support aiding passive relaxation of a weak lower esophageal sphincter with peristalsis. The FDA currently cautions against concurrent use of the LINX® system with cardiac implantable electronic devices (CIEDs) given that the risk of electromagnetic interference (EMI) is unknown, and safety has not been established. We assessed the safety of a transvenous ICD in a patient with the LINX® system. Case Report 59 year old male who previously had the LINX® system implanted after hiatal hernia repair for refractory reflux. Shortly after, he was then diagnosed with apical hypertrophic cardiomyopathy with obstruction (NYHA Class I, genetic testing revealed VUS in CSRP3). Given non-sustained VT on cardiac event monitoring, family history of sudden cardiac death (SCD) and late gadolinium enhancement on cardiac magnetic resonance imaging with a calculated 5-year SCD risk 4.1%, he was recommended ICD implantation for primary prevention. Patient underwent an uneventful transvenous dual chamber defibrillator implantation. Although we do not routinely perform (DFT) testing at our institution, given the coexisting LINX® system in close proximity to the RV lead, we elected to proceed with DFT Testing, which was successful (1 induction: T-wave shock from sinus to VF, 30J delivered successfully to sinus with 7s charge time, no ATP, 70 ohms impedance). Patient underwent routine remote device interrogations and at 1-year follow up (which included an in-person device interrogation), continues to have normal lead parameters (sensing, impedance, threshold), minimal atrial or ventricular pacing, and no recurrent arrhythmias including NSVT (was started on verapamil). Specifically, patient received no inappropriate shocks, and no high frequency noise episodes were detected. We present the first case report of a patient who had a concomitant dual chamber ICD that was implanted shortly after a LINX device placement. We demonstrate normal DFTs at implant and no device interaction at 1 year follow-up, suggesting that ICD implantation without removal of the LINX device might be reasonable. Decision-making for cardiac device implantation decisions in such patients should consider additional theoretical risks until additional data with more patients is available.

MP-453085-11 ALLIED PROFESSIONALS DISPOSITION PATHWAY WITH CONDITIONAL DISCHARGE REDUCES BED UTILIZATION AND HOSPITAL RESOURCES

Increasing demands of inpatient level of care continue to pose challenges to hospital resources and available capacity. Alternative disposition pathways overseen by allied professionals (AP) that utilize extended recovery unit (ERU) hours and conditional discharge (CD) can reduce inpatient bed use, total time spent at the hospital and overall resource utilization. To demonstrate that implementation of disposition pathways utilizing CD and same day discharge (SDD) with an ERU reduces hospital resources without compromising patient safety. An ERU was created to reduce inpatient hospital bed utilization and optimize disposition pathways. This unit included 6 patient beds, 2 registered nurses and overnight coverage. Patients (pts) presenting for elective electrophysiology procedures were classified into three different disposition pathways including SDD, CD and admission to EP allied professional (EP AP) service. All 3 pathways were overseen by EP APs. Pts in the SDD and CD group were required to meet specific criteria noted by the AP to be considered safe for discharge. We compared these new pathways with prior disposition orders in relation to efficiency, safety and resource utilization. From 8/28/2022 to 11/13/2022, 918 pts presented for an EP procedure including cardiac device implantation and ablation. Of these, 200/918(21.8%) were eligible for our disposition pathway. There were 74(8.1%) pts who were SDD, 51(5.6%) pts in the CD pathway, 61(6.6%) pts admitted to the EP AP service, and 14(1.5%) pts were cross-over pathways (failed CD transitioned to EP AP service). The remainder were either already inpatient or felt pre-procedure to require inpatient level of care. Pts evaluated on the EP AP service in the ERU had an average discharge time of 10:04AM vs 12:53PM for pts on the EP AP service admitted to an inpatient unit. Patients in the CD group located in the ERU had an average discharge time of 7:49AM. Discharge time with these pathways improved over time (Figure 1). The total number of pts admitted to the ERU and/or discharged the same day was 186 pts, indicating 186 total hospital beds saved. There were no differences in overall complications between disposition groups compared to prior to implementation of this strategy. The implementation of a disposition pathway strategy utilizing SDD, CD and an ERU overseen by APs is associated with reduced resource utilization without compromising pt safety.