Infective Endocarditis Involving Implanted Cardiac Electronic Devices: JACC Focus Seminar 1/4.

Cardiac implantable electronic device-related infective endocarditis (CIED-IE) encompasses a range of clinical syndromes, including valvular, device lead, and bloodstream infections. However, accurately diagnosing CIED-IE remains challenging owing in part to diverse clinical presentations, lack of standardized definition, and variations in guideline recommendations. Furthermore, current diagnostic modalities, such as transesophageal echocardiography and [18F]-fluorodeoxyglucose positron emission tomography-computed tomography have limited sensitivity and specificity, further contributing to diagnostic uncertainty. This can potentially result in complications and unnecessary costs associated with inappropriate device extraction. Six hypothetical clinical cases that exemplify the diverse manifestations of CIED-IE are addressed herein. Through these cases, we highlight the importance of optimizing diagnostic accuracy and stewardship, understanding different pathogen-specific risks for bloodstream infections, guiding appropriate device extraction, and preventing CIED-IE, all while addressing key knowledge gaps. This review both informs clinicians and underscores crucial areas for future investigation, thereby shedding light on this complex and challenging syndrome.

Atrial fibrillation ablation compared to pacemaker therapy in patients with tachycardia-bradycardia syndrome: A systematic review and updated meta-analysis.

BACKGROUND: Tachycardia-bradycardia syndrome (TBS) is a subtype of sick sinus syndrome characterized by prolonged sinus pause (≥3 s) following termination of tachyarrhythmias, primarily atrial fibrillation (AF). There is controversy regarding whether the long-term prognosis of AF ablation is superior to pacemaker implantation. This study aimed to compare the effects of AF ablation and pacemaker therapy in patients with TBS. METHODS: We conducted a comprehensive search of electronic databases, including PubMed, Cochrane, EmBase, Web of Science, and Chinese BioMedical, up until December 1, 2023. We included studies that reported the effects of AF ablation vs pacemaker therapy in patients with TBS. From this search, we identified 5 studies comprising 843 participants with TBS who underwent catheter AF ablation or pacemaker therapy. RESULTS: Our meta-analysis revealed that AF ablation and pacemaker therapy had similar effects on cardiovascular death (odds ratio [OR] = 0.62 and 95% confidence interval [CI]: 0.14-2.65), procedural complications (OR = 1.53 and 95% CI: 0.67-3.48), and cardiovascular rehospitalization (OR = 0.57 and 95% CI: 0.26-1.22). However, AF ablation provided greater benefits than pacemaker therapy in terms of all-cause mortality (OR = 0.37 and 95% CI: 0.17-0.82), thromboembolism (OR = 0.25 and 95% CI: 0.12-0.49), stroke (OR = 0.28 and 95% CI: 0.13-0.57), heart failure (OR = 0.27 and 95% CI: 0.13-0.56), freedom from AF (OR = 23.32 and 95% CI: 7.46-72.92), and prevention of progression to persistent AF (OR = 0.12 and 95% CI: 0.06-0.24). Furthermore, AF ablation resulted in a reduced need for antiarrhythmic agents (OR = 0.21 and 95% CI: 0.08-0.59). CONCLUSION: AF ablation can effectively reduce the risk of all-cause mortality, thromboembolism, stroke, heart failure, and progression to persistent AF in patients with TBS. Additionally, it may eliminate the need for further pacemaker therapy in most cases after ablation. Therefore, AF ablation is considered superior to pacemaker therapy in the management of patients with TBS.

Stepwise transvenous lead extraction due to pacemaker pocket infection following lactational mastitis complicated with breast abscess.

BACKGROUND: Lactational mastitis is a common painful and debilitating inflammation of breast tissue, generally treated conservatively or with pus puncture in case of breast abscess. However, treating mastitis in patients with implantable surgical material located in the affected breast region can be extremely challenging. We present an unusual case of lactational mastitis complicated by pacemaker pocket infection in a breastfeeding mother. CASE PRESENTATION: A 35-year-old pacemaker-dependent female developed lactational mastitis seven weeks postpartum. Initially, the condition was treated conservatively with analgesics and antibiotics. After abscess formation, pus was aspirated using fine-needle aspiration technique. Four weeks after mastitis resolution, pacemaker pocket infection developed. According to current cardiovascular implantable electronic device infection treatment guidelines a complete surgical extraction of the entire electronic system, followed by targeted antibiotic treatment and reimplantation of a new device after infection resolution, was recommended. However, after thorough discussion with the young woman and her family and after detailed review of surgery-related risks, she declined a potentially high-risk surgical procedure. Thus, only the pulse generator was explanted; pacing leads positioned in the sub-pectoral pocket; new pacemaker implanted on the contralateral side and broad-spectrum antibiotic therapy continued for six weeks. After breastfeeding cessation, and with chronic fistula development at the primary pacemaker implantation site, the possibility of delayed surgical intervention including complete extraction of retained pacemaker leads was again thoroughly discussed with her. After thoughtful consideration the woman consented to the proposed treatment strategy. A surgical procedure including transvenous lead extraction through the primary implantation venous entry site, using hand-powered bidirectional rotational sheaths, was successfully performed, removing all retained leads through the left subclavian venous entry site, and leaving the fully functional and clinically uninfected pacemaker on the contralateral site intact. CONCLUSION: Although patients' decisions for delayed extraction in a case of cardiovascular implantable electronic device infection should be discouraged by attending physicians and members of interdisciplinary teams, our case shows that a stepwise treatment strategy may be successful as a bailout clinical scenario in patients with specific requests, demands and / or clinical needs.

Impact of age over 70 years in the new allocation system on the outcomes of heart transplantation in the US.

BACKGROUND: United Network for Organ Sharing (UNOS) allocation criteria changed in 2018 to accommodate the increased prevalence of patients on a ventricular assist device as a bridge to heart transplant and prioritize sicker people in anticipation of a heart graft. We aimed to assess the impact of patient age in the new allocation policy on mortality following heart transplantation. Secondary outcomes included the effect of age ≥70 on post-transplant events, including stroke, dialysis, pacemaker, and rejection requiring treatment. METHODS: The UNOS Registry was queried to identify patients who underwent heart transplants alone in the US between 2000 and 2021. Patients were divided into groups according to their age (over 70 and under 70 years old). RESULTS: Patients aged over 70 were more likely to require dialysis during follow-up, but less likely to experience rejection requiring treatment, compared with patients aged <70. Age ≥70 in the new allocation system was a significant predictor of 1-year mortality (adjusted HR: 1.41; 95% CI: 1.05-1.91; p = .024), but its effect on 5-year mortality was not significant after adjusting for potential confounders (adjusted HR: 1.27; 95% CI:.97-1.66; p = .077). Undergoing transplantation under the new allocation policy vs the old allocation policy was not a significant predictor of mortality in patients over 70 years old. CONCLUSIONS: Age ≥70 is a significant predictor of 1-year mortality following heart transplantation, but not at 5 and 10 years; however, the new allocation does not seem to have changed the outcomes for this group of patients.

Transient 2:1 Atrioventricular Block with Peri-Conduction System Pacing After Leadless Pacemaker Implantation.

This report discusses a case of transient 2:1 atrioventricular block with conduction system pacing 4 hours after leadless right ventricular pacemaker implantation in a 19-year-old patient with a history of cardioinhibitory syncope and asystole cardiac arrest but without preexisting atrioventricular block. The atrioventricular block was resolved spontaneously. Pacing morphology was suggestive of right bundle branch pacing. Neither 2:1 atrioventricular block nor conduction system pacing has previously been a reported outcome of right ventricular leadless pacemaker implantation. The report demonstrates that conduction system pacing with leadless devices is achievable. Further study of techniques, limitations, and complications related to intentional right ventricular leadless conduction system pacing is warranted.

Leadless pacemakers at 5-year follow-up: the Micra transcatheter pacing system post-approval registry.

BACKGROUND AND AIMS: Prior reports have demonstrated a favourable safety and efficacy profile of the Micra leadless pacemaker over mid-term follow-up; however, long-term outcomes in real-world clinical practice remain unknown. Updated performance of the Micra VR leadless pacemaker through five years from the worldwide post-approval registry (PAR) was assessed. METHODS: All Micra PAR patients undergoing implant attempts were included. Endpoints included system- or procedure-related major complications and system revision rate for any cause through 60 months post-implant. Rates were compared through 36 months post-implant to a reference dataset of 2667 transvenous pacemaker patients using Fine-Gray competing risk models. RESULTS: 1809 patients were enrolled between July 2015 and March 2018 and underwent implant attempts from 179 centres in 23 countries with a median follow-up period of 51.1 months (IQR: 21.6-64.2). The major complication rate at 60 months was 4.5% [95% confidence interval (CI): 3.6%-5.5%] and was 4.1% at 36 months, which was significantly lower than the 8.5% rate observed for transvenous systems (HR: .47, 95% CI: .36-.61; P < .001). The all-cause system revision rate at 60 months was 4.9% (95% CI: 3.9%-6.1%). System revisions among Micra patients were mostly for device upgrades (41.2%) or elevated thresholds (30.6%). There were no Micra removals due to infection noted over the duration of follow-up. At 36 months, the system revision rate was significantly lower with Micra vs. transvenous systems (3.2% vs. 6.6%, P < .001). CONCLUSIONS: Long-term outcomes with the Micra leadless pacemaker continue to demonstrate low rates of major complications and system revisions and an extremely low incidence of infection.

Implantable loop recorders in patients with Brugada syndrome: the BruLoop study.

BACKGROUND AND AIMS: Available data on continuous rhythm monitoring by implantable loop recorders (ILRs) in patients with Brugada syndrome (BrS) are scarce. The aim of this multi-centre study was to evaluate the diagnostic yield and clinical implication of a continuous rhythm monitoring strategy by ILRs in a large cohort of BrS patients and to assess the precise arrhythmic cause of syncopal episodes. METHODS: A total of 370 patients with BrS and ILRs (mean age 43.5 ± 15.9, 33.8% female, 74.1% symptomatic) from 18 international centers were included. Patients were followed with continuous rhythm monitoring for a median follow-up of 3 years. RESULTS: During follow-up, an arrhythmic event was recorded in 30.7% of symptomatic patients [18.6% atrial arrhythmias (AAs), 10.2% bradyarrhythmias (BAs), and 7.3% ventricular arrhythmias (VAs)]. In patients with recurrent syncope, the aetiology was arrhythmic in 22.4% (59.3% BAs, 25.0% VAs, and 15.6% AAs). The ILR led to drug therapy initiation in 11.4%, ablation procedure in 10.9%, implantation of a pacemaker in 2.5%, and a cardioverter-defibrillator in 8%. At multivariate analysis, the presence of symptoms [hazard ratio (HR) 2.5, P = .001] and age >50 years (HR 1.7, P = .016) were independent predictors of arrhythmic events, while inducibility of ventricular fibrillation at the electrophysiological study (HR 9.0, P < .001) was a predictor of VAs. CONCLUSIONS: ILR detects arrhythmic events in nearly 30% of symptomatic BrS patients, leading to appropriate therapy in 70% of them. The most commonly detected arrhythmias are AAs and BAs, while VAs are detected only in 7% of cases. Symptom status can be used to guide ILR implantation.

Atrial Pacing Negatively Affects Left Atrial Morphological and Functional Parameters Similarly to Atrioventricular Dyssynchrony.

Background and Objectives: Atrioventricular (AV) dyssynchrony as well as atrial and ventricular pacing affect left atrial (LA) function. We conducted a study evaluating the effect of atrial and ventricular pacing on LA morphological and functional changes after dual-chamber pacemaker implantation. Materials and Methods: The study prospectively enrolled 121 subjects who had a dual-chamber pacemaker implanted due to sinus node disease (SND) or atrioventricular block (AVB). Subjects were divided into three groups based on indication and pacemaker programming: (1) SND DDDR 60; (2) AVB DDD 60 and (3) AVB DDD 40. Subjects were invited to one- and three-month follow-up visits. Three subsets based on pacing burden were analyzed: (1) high atrial (A) low ventricular (V); (2) high A, high V and (3) low A, high V. LA function was assessed from volumetric parameters and measured strains from echocardiography. Results: The high A, low V group consisted of 38 subjects; while high A, high V had 26 and low A, high V had 23. A significant decrease in reservoir and contractile LA strain parameters were only observed in the high A, low V pacing group after three months (reservoir 25.9 ± 10.3% vs. 21.1 ± 9.9%, p = 0.003, contractile -14.0 ± 9.0% vs. -11.1 ± 7.8, p = 0.018). While the re-established atrioventricular synchrony in the low A, high V group maintained reservoir LA strain at the baseline level after three months (21.4 ± 10.4% vs. 22.5 ± 10.4%, p = 0.975); in the high A, high V group, a further trend to decrease was noted (20.3 ± 8.9% vs. 18.7 ± 8.3%, p = 0.231). Conclusions: High atrial pacing burden independently of atrioventricular dyssynchrony and ventricular pacing impairs LA functional and morphological parameters. Changes appear soon after pacemaker implantation and are maintained.

Reasons for repeat urgent cardiac procedures within the same day.

BACKGROUND: With advances in technology and technique, the expectations are that patients undergoing procedures in the cardiac catheterization laboratory will not need to return for a repeat procedure within the same day. OBJECTIVES: Report why subjects undergoing cardiac procedures return urgently to the catheterization laboratory for a repeat procedure during the same day. METHODS: We retrospectively reviewed patients who were brought back to the cardiac catheterization laboratory within the same day for a repeat procedure. The reasons for index and repeat procedure were identified. Patients who were transferred from an outside center after an initial procedure at other centers were excluded. RESULTS: Between November 2013 and January 2022, 55,942 catheterization procedures were performed at our institution, of which 140 entries were included in our analysis. Common reasons for the index procedure were diagnostic angiography (35.0%), percutaneous coronary intervention (PCI, 29.2%), and transcatheter aortic valve replacement (15.0%). The most common reason for bringing these patients back to the cardiac catheterization laboratory within the same day was vascular complications (24.2%), followed by repeat PCI (20.7%), need for hemodynamic support (15.0%), heart team discussion and PCI (10%), and pacemaker implantation (10%). Acute limb ischemia was the most commonly identified vascular complication (7.1%), followed by pseudoaneurysm (5%). CONCLUSION: Our study demonstrates that a very small number of patients underwent repeat procedures within the same day. Special attention should be paid to vascular access and closure and assessment of recurrent chest pain postprocedure, as these are the main reasons for same-day repeat procedures.

Association of Antiarrhythmic Drug Therapy With Syncope and Pacemaker Implantation in Patients With Atrial Fibrillation.

BACKGROUND: Early rhythm control therapy mainly with antiarrhythmic drugs (AADs) for new-onset atrial fibrillation (AF) reduces major adverse cardiovascular events. However, negative dromotropic effects of AADs via ion channel blocking may cause bradyarrhythmias. OBJECTIVES: This study aimed to evaluate the association between AAD use and the risk of pacemaker implantation or syncope in patients with new-onset AF receiving early rhythm control therapy with AADs. METHODS: This study was based on data from the Korean National Health Insurance Service system. We screened all new-onset AF diagnoses that occurred from 2013 to 2019 and identified patients who were prescribed AADs within 1 year of AF diagnosis. The risk of pacemaker implantation or syncope was compared between AAD users and nonusers. RESULTS: A total of 770,977 new-onset AF cases were identified and 142,141 patients were prescribed AADs. After multivariate adjustment, use of AADs was associated with 3.5-, 2.0-, and 5.0-fold increased risk of pacemaker implantation or syncope, syncope, and pacemaker implantation, respectively. Propensity score-matched analysis revealed similar results, demonstrating a significant association between AAD use and the risk of pacemaker implantation or syncope. This association was consistent across various subgroups. Women were more susceptible to adverse effects of AADs than men. CONCLUSIONS: This study showed an association between AADs and risk of pacemaker implantation or syncope, a consistent finding across various subgroups. Precise evaluation of such risk should be undertaken before prescription of AADs.

Temporary pacing following cardiac surgery - a reference guide for surgical teams.

Temporary pacing wires are often used following cardiac surgery to optimise the heart rhythm. Although setting and checking temporary pacemakers is typically undertaken by anaesthetists, intensivists, and nursing staff who care for post-cardiac surgical patients, almost all patients with temporary pacing wires are transferred to the ward with the pacing wires left in situ, where surgical, often junior, staff become responsible for temporary pacing wire management. Thus, knowledge is required not only of temporary pacing wire indications, types, and positioning at surgery, but also of practical skills in performing a pacing check, setting the pacemaker, and troubleshooting common problems. The available literature targets clinicians well-versed in temporary pacing wire management. However, this paper provides a practical 'how to' for surgical staff managing temporary pacing wires in a non-critical care environment.

Postoperative Atrioventricular Block in Pediatric Patients: Impact of Congenital Cardiac Malformations and Medications.

Postoperative atrioventricular block may occur after pediatric cardiac surgery. A small proportion of those who develop atrioventricular block will require pacemaker placement. The primary aim of this study was to determine factors associated with postoperative atrioventricular block. Secondary aims included determining factors associated with pacemaker placement in those with atrioventricular block. Data from the PHIS data were utilized to identify patients under 18 years of age who underwent cardiac surgery. Those who did and did not develop atrioventricular block. Univariable analyses and regression analyses were conducted to determine factors associated with postoperative atrioventricular block. Similar analyses were conducted to determine factors associated with pacemaker placement in those with atrioventricular block. A total of 43,716 admissions were identified. Of these, 2093 (5%) developed atrioventricular block and 480 (1% of total admissions) underwent pacemaker placement. Approximately 70% of those with atrioventricular block received steroids but this was not associated with a decrease in pacemaker placement. Risk factors (congenital malformations of the heart, comorbidities, medications) associated with increased risk of atrioventricular block and pacemaker placement were identified. Postoperative atrioventricular block occurred in 5% of pediatric admissions for cardiac surgery. Of these admissions with postoperative atrioventricular block, 23% required pacemaker placement. Isoproterenol and steroids were not associated with a reduction in the likelihood of pacemaker placement.

Diferencias clínicas entre la amiloidosis cardiaca por transtirretina y la cardiopatía hipertensiva / Clinical differences between transthyretin cardiac amyloidosis and hypertensive heart disease

Introducción: Un porcentaje importante de pacientes finalmente diagnosticados de amiloidosis cardIaca por transtirretina (ATTR) fueron previamente diagnosticados de cardiopatía hipertensiva (CHTA), ya que ambas enfermedades suelen cursar con insuficiencia cardíaca (IC) con fracción de eyección preservada (ICFEp) e hipertrofia ventricular. Nuestros objetivos fueron evaluar las diferencias clínicas, electrocardiográficas y ecocardiográficas, y analizar si existe un pronóstico diferencial entre ambas entidades nosológicas. Material y métodos: Se incluyeron retrospectivamente todos los pacientes con CHTA a los que se solicitó una gammagrafía cardíaca con 99mTc-Difosfonatos (GDPD) y estudio de cadenas ligeras en sangre y orina para despistaje de ATTR en nuestro centro, en el periodo 2016-2021. Para el análisis, se excluyeron aquellos diagnosticados de otros tipos de amiloidosis. Resultados: Se analizaron un total de 72 pacientes: 33 fueron diagnosticados de ATTR y 39 de CHTA, finalmente. Los pacientes con ATTR presentaron mayores niveles de troponina I ultrasensible (TnI-US) y propéptido natriurético cerebral N-terminal (NT-ProBNP); en electrocardiograma (ECG) presentaron más frecuentemente patrón de seudoinfarto y alteraciones de la conducción; en ecocardiograma transtorácico (ETT) presentaron mayor grado de hipertrofia ventricular, disfunción ventricular izquierda y parámetros de peor función diastólica, con presiones de llenado más elevadas. En el seguimiento a 4 años, el grupo de ATTR mostró mayor necesidad de marcapasos (MCP), sin evidenciarse evidencias en cuanto a mortalidad, desarrollo de fibrilación auricular o más ingresos por IC. Conclusiones: En nuestra serie, los pacientes con ATTR presentaron diferencias clínicas, electrocardiográficas y ecocardiográficas respecto a aquellos con CHTA, con mayor riesgo necesidad de MCP en el seguimiento.(AU)

Introduction: A significant percentage of patients eventually diagnosed with cardiac transthyretin amyloidosis (TTRA) was previously diagnosed with hypertensive heart disease (HHD), since both conditions usually present with heart failure (HF) with preserved ejection fraction (HFpEF) and ventricular hypertrophy. Our objectives were to evaluate the clinical, electrocardiographic and echocardiographic differences, and to analyse whether there exists a differential prognosis between these two nosological entities. Materials and methods: We retrospectively included all patients with HHD for whom a cardiac scintigraphy with 99mTc-diphosphonate (GDPD) and a free light chains test in blood and urine were ordered for ATTR screening in our centre, in the period between 2016 and 2021. Those diagnosed with other types of amyloidosis were excluded from the analysis. Results: A total of 72 patients were analyzed: 33 were finally diagnosed with TTRA and 39 with CHTA. Patients with TTRA had higher levels of ultrasensitive troponin I (TnI-US) and N-terminal brain natriuretic propeptide (NT-ProBNP); in electrocardiography (ECG) they presented a pseudo-infarction pattern more frequently as well as conduction disturbances; in echocardiography (TTE) they presented a higher degree of ventricular hypertrophy, left ventricular dysfunction and worse diastolic function parameters, with elevated filling pressures. In the 4-year follow-up, the ATTR group showed greater need for pacemaker (PCM), with no evidence regarding mortality, development of atrial fibrillation (AF), or more admissions for heart failure (HF). Conclusions: In our series, patients with TTRA showed clinical, electrocardiographic and echocardiographic differences compared to patients with HHD, with increased risk of need for PCM.(AU)

Impacto de la pandemia por COVID-19 en el implante de dispositivos cardiacos implantables y las activaciones de la monitorización a distancia / Impact of the COVID-19 pandemic on implantation of cardiac implantable electronic devices and remote monitoring activations

Introducción y objetivos La monitorización a distancia (MD) de los dispositivos cardiacos implantables (DCI) se considera más fiable, eficiente y segura que los convencionales seguimientos presenciales, aunque su implantación es aún subóptima. Este estudio pretende analizar el impacto de la pandemia de COVID-19 en las tasas de implantes y activaciones de MD de DCI en España. Métodos Se utilizó el Registro COVID-19 de MD en España para analizar el número mensual de todos los implantes de DCI y activaciones de MD desde enero de 2018 hasta diciembre de 2021 en España. Se sumaron los datos de los 5 principales fabricantes de DCI y se analizaron de manera descriptiva. Resultados Se registró un total de 205.345 DCI. El número de implantes disminuyó bruscamente (48,2%) con el confinamiento (marzo a junio de 2020) y aumentó progresivamente después hasta compensar la reducción previa, excepto en marcapasos y desfibriladores automáticos implantables (DAI), con una pérdida agregada (2020-2021) del 7 y el 3%, respectivamente, respecto a la media anual. Aumentaron la terapia de resincronización cardiaca con desfibrilador (TRC-D, 17%) y con marcapasos (TRC-P, 4,5%) a los 2 años. El porcentaje de activaciones de MD aumentó del 24,5% en 2018 al 49,0% en 2021, con un fuerte aumento durante el confinamiento. Las tasas de activación de MD aumentaron invariablemente durante el confinamiento con todos los dispositivos: marcapasos (el 14,4 frente al 37,2%; p<0,001); DAI (el 75,6 frente al 94,2%; p<0,001); TRC-D/TRC-P (del 68,6/44,2% al 81,6/61%; p<0,001), y Holters implantables (el 50,2 frente al 68,7%; p<0,001). Conclusiones La significativa reducción de los implantes que se produjo durante el confinamiento se recuperó gradualmente después, excepto los de marcapasos y DAI. La pandemia de COVID-19 impulsó la MD de todos los DCI en España. (AU)

Introduction and objectives Remote monitoring (RM) of cardiac implantable electronic devices (CIEDs) is considered more reliable, efficient, and safer than conventional in-person follow-up. However, the implementation of RM is still suboptimal. This study aimed to analyze the impact of the COVID-19 pandemic on the rates of CIED implants and RM activations in Spain. Methods The COVID-19 RM Spain Registry was used to analyze the monthly number of all CIED implantations and RM activations from January 2018 to December 2021. A descriptive analysis was performed using aggregated data from the five major CIED manufacturers. Results A total of 205 345 CIEDs were recorded. The number of implants decreased sharply (48.2%) during the pandemic lockdown (March-June 2020) but gradually increased thereafter, compensating for the previous reduction. However, pacemakers and implantable cardiac defibrillators (ICD) showed an aggregate loss of 7% and 3%, respectively, from the annual average during 2020-2021. In contrast, cardiac resynchronization therapy defibrillators (CRT-D) increased by 17%, and pacemakers (CRT-P) by 4.5% over the 2-year period. The percentage of RM activations increased from 24.5% in 2018 to 49.0% in 2021, with a sharp increase during the lockdown. The RM activation rates consistently increased during the lockdown for all devices: pacemakers (14.4% vs 37.2%; P<.001); ICD (75.6% vs 94.2%; P<.001); CRT-D/CRT-P (68.6-44.2% vs 81.6-61%; P<.001), and implantable loop recorders (50.2% vs 68.7%; P<.001). Conclusions The significant decline in implants during the lockdown gradually recovered, except for pacemakers and ICD. However, the COVID-19 pandemic boosted RM for all CIEDs in Spain. (AU)

Aveir VR real-world performance and chronic pacing threshold prediction using mapping and fixation electrical data.

AIMS: Aveir VR performance and predictors for its pacing threshold (PCT) in a real-world cohort were investigated. METHODS: Electrical measurements at various stages of an Aveir VR implant were prospectively collected. Predictors for 3-month PCT were studied. A retrospective cohort of consecutive 139 Micra implants was used to compare the PCT evolution. High PCT was defined as ≥1.5 V, using a pulse width of 0.4 ms for Aveir and 0.24 ms for Micra. Excellent PCT was defined as ≤0.5 V at the respective pulse width. RESULTS: Among the 123 consecutive Aveir VR implant attempts, 122 (99.2%) were successful. The majority were of advanced age (mean 79.7) and small body size (mean BSA 1.60). Two patients (1.6%) experienced complications, including one pericardial effusion after device reposition and one intraoperative device dislodgement. Eighty-eight patients reached a 3-month follow-up. Aveir 3-month PCT was correlated with impedance at mapping (P = 0.015), tether mode (P < 0.001), end-of-procedure (P < 0.001), and mapping PCT (P = 0.035), but not with PCTs after fixation (P > 0.05). Tether mode impedance >470 ohms had 88% sensitivity and 71% specificity in predicting excellent 3-month PCT. Although it is more common for Aveir to have high PCT at end of procedure (11.5% for Aveir and 2.2% for Micra, P = 0.004), the rate at 3 months was similar (2.3% for Aveir and 3.1% for Micra, P = 1.000). CONCLUSION: Aveir VR demonstrated satisfactory performance in this high-risk cohort. Pacing thresholds tend to improve to a greater extent than Micra after implantation. The PCT after fixation, even after a waiting period, has limited predictive value for the chronic threshold. Low-mapping PCT and high intraoperative impedance predict chronic low PCT.