Leadless pacemaker implantation following tricuspid interventions: multicenter collaboration of feasibility and safety.

BACKGROUND: Permanent pacing is often required following valve intervention (either surgical or percutaneous); however, tricuspid interventions pose specific challenges to conventional pacing. Therefore, leadless pacemaker (LP) implantation may be the preferred strategy when permanent pacing is required after tricuspid valve intervention. PURPOSE: To report periprocedural outcomes and follow-up of patients undergoing implantation of a LP system following tricuspid valve interventions. METHODS: Patients with previous tricuspid valve intervention at the time of attempted implantation of a LP (MicraTM, Medtronic, Minneapolis, MN, USA) were included. RESULTS: Between 2019 and 2022, 40 patients underwent LP implantations following tricuspid interventions in 5 large tertiary centers. The mean age was 68.9 ± 13.7 years, and 48% patients were male. The indication for pacing was as following: AVB in 27 (68%) patients, AF with slow ventricular response in 10 (25%) patients, and refractory rapid atrial fibrillation (AF) referred to AV junction ablation in 3 (7%) patients. Most of the patients received Micra VR (78%). The procedure was successful in all patients. The mean procedural time is 58 ± 32 min, and the median fluoroscopy time is 7.5 min. Electrical parameters were within normal range (threshold: 1.35 ± 1.2 V@0.24 ms, impedance: 772 ± 245 Ohm, R-wave: 6.9 ± 5.4 mV). No acute complications were observed. During a mean follow-up of 10 months, electrical parameters remained stable, and 4 deaths were occurred (not related to the procedure). CONCLUSION: A LP is a safe and efficient option following tricuspid valve interventions.

Pacemaker-induced Cardiomyopathy in Patients with Coronary Artery Disease: A Report of Three Cases.

Pacing-induced cardiomyopathy (PICM) is defined as a drop in left ventricular ejection fraction (LVEF) in the setting of chronic, high-burden right ventricular pacing. Cardiac resynchronization therapy (CRT) and conduction system pacing (CSP) have been proposed to manage PICM. Although acute myocardial infarction has been described as a predictor of PICM, there are no guideline recommendations for CRT or CSP in patients with coronary artery disease (CAD) and preserved LVEF. In this report, we present and discuss three cases of PICM in patients with CAD and preserved LVEF.

Perforation of the Pulmonary Vein During Ablation of Atrial Fibrillation: A Rare Complication of Cryoballoon Ablation.

A 58-year-old man admitted for a cryoballoon ablation due to a history of symptomatic paroxysmal atrial fibrillation experienced pericardial effusion and cardiac tamponade intraoperatively. A longitudinal left superior pulmonary vein perforation was confirmed by emergency thoracotomy and repaired. He developed atrial fibrillation 2 days postoperatively, which was terminated with colchicine and oral steroids the following day.

Brugada phenocopy associated with multiple psychotic drugs.

Brugada phenocopy (BrP) is a clinical condition characterized by transient ECG changes of Brugada syndrome (BrS), which can be due to various clinical conditions. We describe a case report of BrP due to psychotic drugs.

Captagon-induced Brugada phenocopy: A report of two cases.

Brugada phenocopies (BrP) represent electrocardiogram changes identical to those of true congenital Brugada syndrome but are induced by reversible clinical conditions. Previous cases have been reported in patients following recreational drug use. This report presents two cases of type 1B BrP associated with Fenethylline abuse, a recreational drug known by its trade name, Captagon.

Left bundle branch area pacing in patients with atrioventricular conduction disease: A prospective multicenter study.

BACKGROUND: The reported success rate of His-bundle pacing (HBP) in patients with infranodal atrioventricular (AV) conduction disease is only 52%-76%. The success rate of left bundle branch area pacing (LBBAP) in this cohort is not well studied. OBJECTIVE: The purpose of this study was to evaluate the feasibility, safety, and electrophysiological characteristics of LBBAP in patients with AV conduction disease. METHODS: Patients with AV conduction disease referred for pacemaker implantation at 2 centers between February 2019 and June 2021 were considered for LBBAP. Baseline demographic characteristics, procedural success rates, electrophysiological parameters, and complications were assessed. RESULTS: LBBAP was successful in 340 of 364 patients (93%). Mean age was 72 ± 13 years, and mean follow-up was 331 ± 244 days. Pacing indications were Mobitz I in 27 patients (7%), Mobitz II or 2:1 AV block or high-grade AV block in 94 patients (26%), complete heart block in 199 patients (55%), and sick sinus syndrome with isolated bundle branch block in 44 patients (12%). Left bundle branch block and right bundle branch block were present in 57 patients (16%) and 140 patients (38%), respectively. Procedural success rates did not differ between indications (92.6%, 93.6%, 92.9%, and 95%, respectively) or between patients with narrow (<120 ms) vs wide QRS (≥120 ms). Mean LBBAP threshold was 0.77 ± 0.34 V at 0.4 ms at implant and remained stable during follow-up. There were 4 (1.2%) acute LBBAP lead dislodgments. CONCLUSION: LBBAP is safe and feasible with high success rates for patients with AV conduction disease. In contrast to HBP, LBBAP success rates remain high over the entire spectrum of AV conduction disease, and lead parameters remain stable during follow-up.

Ablation Index Outcome in Redo Persistent Atrial Fibrillation Ablation: Results of a Short-Term Study.

Background: Ablation index (AI) is a novel catheter-based parameter that has improved the outcome and safety of radiofrequency (RF) ablation of pulmonary vein isolations (PVIs). This index incorporates contact force (CF) (g), time (s), and power (W) parameters. The role of AI in redo ablations for persistent atrial fibrillation (peAF) has not been fully investigated. Hence, the impact of AI on the success of the redo PVI during the short-term follow-up period is the aim of this study. Methods: A retrospective analysis of 39 consecutive patients who underwent redo PVI ablations for peAF was carried out between January 2016 and December 2018. Target values for AI were 500 - 550 for anterior and roof and 400 - 380 for posterior and inferior regions. We compared outcomes between AI-guided and catheter CF ablations (i.e., forced time integral (FTI) of more than 400 g/s) during a follow-up of 24 months. Results: Pulmonary vein reconnections at redo procedure were similar in both groups (P = 0.1). AF free burden period was non-significant (mean 15.53 ± 2.4 months in AI group vs. 15.22 ± 1.9 months in CF group, P = 0.79) at 24 months. The AI group demonstrated greater numbers of patients for whom anti-arrhythmic therapy could be de-escalated over 1 year (n = 11 (65%) in AI vs. n = 6 (27%) in CF, P = 0.02). Fewer patients underwent escalation of their anti-arrhythmic therapy (n = 2 (12%) in AI vs. n = 7 (32%) in CF, P = 0.15). The AI group trended towards a shorter procedure time (111.6 ± 27 min) compared to the CF group (133 ± 40 min) (P = 0.06). Other procedural details were comparable. Conclusion: Redo PVI interventions using AI lead to a significant de-escalation in medication during follow-up. Procedure time and radiation dose using AI tends to be shorter. Both techniques are safe with minimal complications.

Successful Implantation of a Leadless Pacemaker in a Patient With a Tricuspid Clip.

Leadless pacemakers have become an effective alternative to conventional transvenous pacemakers to prevent the risk of lead failure, pocket complications, and iatrogenic tricuspid regurgitation. The current transcatheter approach for tricuspid valve repair can limit the implantation of these devices, unless the procedure is performed with appropriate image guidance. We present the case of a patient with severe tricuspid regurgitation secondary to pacemaker lead impingement who, despite the implantation of a tricuspid clip, received a leadless pacemaker. The procedure was successfully guided by transthoracic echocardiography, an alternative to transesophageal or intracardiac echocardiography.

Les stimulateurs cardiaques sans électrodes sont devenus une solution de rechange efficace aux stimulateurs transveineux classiques pour prévenir le risque de défaillance des électrodes, les complications liées à la loge et la régurgitation tricuspidienne iatrogène. L'approche actuelle de réparation de la valve tricuspide par cathétérisme peut empêcher l'implantation de ces dispositifs, à moins que l'intervention ne soit réalisée avec un guidage par image approprié. Nous présentons le cas d'un patient ayant une régurgitation tricuspidienne grave consécutive à la compression des électrodes d'un stimulateur cardiaque qui, malgré l'implantation d'un clip tricuspide, a reçu un stimulateur cardiaque sans électrodes. L'intervention a été guidée avec succès au moyen d'une échocardiographie par voie transthoracique, une solution de rechange à l'échocardiographie transœsophagienne ou intracardiaque.

Safety and feasibility of left bundle branch area pacing following valvular interventions: Multicenter study.

OBJECTIVES: To evaluate the safety and feasibility of left bundle branch area pacing (LBBAP) in patients with valvular interventions. METHODS: Eighty-four patients were included in this study. All patients underwent recent surgical or percutaneous valvular interventions. LBBAP was attempted in all patients. Implant success rates, peri- and postprocedure electrocardiogram, pacing parameters, and complications were assessed at implant, and during follow-up. RESULTS: LBBAP implantation was successful in 80/84 (95%) patients. Mean age was 74.1 ± 13.8 years and 56% patients were male. Prior valvular replacements included: percutaneous aortic (26), surgical aortic (36), combined surgical aortic plus mitral (6), MVR (10), tricuspid (1), and pulmonic (1). Average LVEF was 52.6 ± 11%. Majority of patients underwent LBBAP due to atrioventricular block (76%) and sinus node disease (13%). Total procedure duration was 74.1 ± 12.5 min and fluoroscopic duration was 9.7 ± 6.8 min. Pacing parameters were stable during follow-up period of 10.0 ± 6.3 months. Pacing QRS duration was significantly narrower than baseline QRS duration (131.5 ± 31.4 ms vs. 114.3 ± 13.7 ms, p < .001, respectively). No acute complications were observed. Mean follow-up was 10.0 ± 6.3 months (median: 8.4 months, min: 1 and max: 24 months). During follow-up, there were three device infections and two patients had loss of LBBA capture within 1 month of implant. CONCLUSIONS: LBBAP is a feasible and safe pacing modality in patients with prior interventions for valvular heart disease.

Importance of Polarity Reversal in Leads I/aVL in the Diagnosis of an Accessory Pathway Originating from the Aortomitral Continuity.

Accessory pathways (APs) are commonly located around the tricuspid and mitral annulus; however, they can be rarely seen in unusual locations like the aortomitral continuity (AMC), the right atrium to the right ventricular outflow region, and the left atrial appendage to left ventricle connection. Although several electrocardiogram algorithms have been proposed to localize the AP, the sensitivity of these algorithms is not high and they may fail to localize the mentioned unusual localizations. In this report, we describe a case of a 37-year-old man presenting with an AP originating from the AMC, which was successfully ablated.

The Importance of Arrhythmia Burden for Outcomes and Management Related to Catheter Ablation of Atrial Fibrillation.

Atrial fibrillation (AF) ablation has been shown to be an effective treatment for AF, although our understanding of AF ablation outcomes until now, has been based on AF recurrence as a dichotomous variable. Reduction in AF burden, defined as the proportion of time that an individual is in AF during a monitoring period, has been already correlated to an improvement in quality of life and is likely a better assessment of success. Clinically, many patients may still have a few short recurrences of AF but feel much better. In addition, several studies have related higher AF burden with poorer health outcomes and a higher risk of stroke. Despite the growing understanding of AF burden, it is not clear yet which threshold of AF burden would be considered an appropriate outcome measure for AF ablation. Further investigations are needed to address that question. However, the reduction of AF burden seems to be a more accurate reflection of procedural success and a better predictor of prognosis and stroke risk than a single measure of AF.

Arrhythmias and electrocardiographic findings in Coronavirus disease 2019: A systematic review and meta-analysis.

BACKGROUND: Coronavirus disease 2019 (COVID-19) primarily causes lung infection, but recent studies have shown that cardiac involvement is associated with a worse prognosis. OBJECTIVES: We conducted a systematic review and meta-analysis to examine the prevalence of cardiac arrhythmias detected by the electrocardiogram and their relationships with adverse outcomes in patients with COVID-19. METHODS: PubMed and Google were searched for studies that reported on cardiac arrhythmias and/or examined the relationship between arrhythmias and adverse outcomes. RESULTS: Thirty studies with 12,713 participants were included in the systematic review, and 28 studies (n = 12,499) in the meta-analysis. The mean age was 61.3 ± 16.8 years; 39.3% were female. In 25 studies with 7578 patients, the overall prevalence of cardiac arrhythmias was 10.3% (95% confidence interval [CI]: 8.4%-12.3%). The most common arrhythmias documented during hospitalization were supraventricular arrhythmias (6.2%, 95% CI: 4.4%-8.1%) followed by ventricular arrhythmias (2.5%, 95% CI: 1.8%-3.1%). The incidence of cardiac arrhythmias was higher among critically ill patients (relative risk [RR]: 12.1, 95% CI: 8.5-17.3) and among non-survivors (RR: 3.8, 95%, CI: 1.7-8.7). Eight studies reported changes in the QT interval. The prevalence of QTc > 500 ms was 12.3% (95% CI: 6.9%-17.8%). ST-segment deviation was reported in eight studies, with a pooled estimate of 8.7% (95% CI: 7.3% to 10.0%). CONCLUSION: Our meta-analysis showed that QTc prolongation, ST-segment deviation, and various other cardiac arrhythmias were observed in patients hospitalized with COVID-19. The presence of cardiac arrhythmias was associated with a worse prognosis.

A New Era in Epicardial Access for the Ablation of Ventricular Arrhythmias: The Epi-Co2 Registry.

OBJECTIVES: This multicenter registry aimed to assess the reproducibility and safety of intentional coronary vein exit and carbon dioxide insufflation to facilitate subxiphoid epicardial access in the setting of ventricular tachycardia ablation. BACKGROUND: Epicardial ablation for ventricular tachycardia is not a widespread technique due to the significant potential complications associated with subxiphoid puncture. The first experience in 12 patients showed that intentional coronary vein exit and carbon dioxide insufflation was technically feasible. METHODS: A branch of the coronary sinus was cannulated by means of a diagnostic JR4 coronary catheter. Intentional perforation at the distal portion of that branch was performed with a high tip load 0.014-inch angioplasty wire. A microcatheter was advanced over the wire into the pericardial space. Carbon dioxide was then insufflated into the pericardial space, allowing direct visualization of the anterior pericardial space to facilitate subxiphoid puncture. RESULTS: Intentional coronary vein exit was attempted in 102 consecutive patients in 16 different centers and successfully completed in 101 patients. Significant pericardial adhesions were confirmed in 3 patients, preventing carbon dioxide insufflation and epicardial ablation. None of the punctures were complicated with inadvertent right ventricular puncture or damage to a coronary artery. Significant bleeding (>80 ml) due to coronary vein exit occurred in 5 patients, without hemodynamic compromise. None of the patients required surgery. CONCLUSIONS: Coronary vein exit and carbon dioxide insufflation can be safely and reproducibly achieved to facilitate subxiphoid pericardial access in the setting of ventricular tachycardia ablation.

Value of electrocardiography in coronavirus disease 2019 (COVID-19).

In December 2019, reports of an unknown pneumonia not responsive to traditional treatments arose in Wuhan, China. The pathogen was subsequently identified as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), known to be responsible for the coronavirus disease-2019 (COVID-19) illness, and public health emergency of international concern was declared by the World Health Organization. There is increasing awareness of the cardiovascular manifestations of COVID-19 disease, and the adverse impact of cardiovascular involvement on its prognosis. In this setting, the electrocardiogram (ECG) is one of the leading tools to assess the extent of cardiac involvement in COVID-19 patients, due to its wide disponibility, low cost, and the possibility of remote evaluation. In this article, we review the role of the ECG in the identification of cardiac involvement in COVID-19, highlighting relevant clinical implications.

Rate-dependent aberrancy and cardiac resynchronization therapy.

Left bundle branch block (LBBB) can result in significant dyssynchrony in left ventricular (LV) contraction, ultimately leading to cardiac remodeling. LBBB can be rate dependent and may appear with LV systolic dysfunction. Cardiac resynchronization therapy (CRT) has been demonstrated to improve hemodynamics as well as clinical symptoms in patients with LBBB. We describe the case of a 57-year-old man who underwent CRT implantation due to exertional dyspnea, rate-dependent LBBB, and impaired left LV systolic function.

Successful leadless pacemaker implantation in a patient with profound bradycardia following transcatheter aortic valve replacement and mitral valve-in-valve procedure.

Leadless pacemakers provide a potential alternative to conventional transvenous pacemakers for patients undergoing high-risk transcatheter valve replacement procedures. This is a description of a successful leadless pacemaker implantation in a 51-year-old woman who developed profound bradycardia following a transcatheter aortic valve replacement and mitral valve-in-valve procedure.

Validation of a smartphone-based electrocardiography in the screening of QT intervals in children.

OBJECTIVE: A 12-lead electrocardiography is a critical component for the screening of long QT syndrome; however, besides, an electrocardiograph, trained personnel are also necessary which limits the screening capability of conventional electrocardiographs. The development of smartphone electrocardiography technologies provides a potential alternative platform for electrocardiography screening for selective purposes such as arrhythmias and QT interval abnormalities. The aim of this pilot study was to assess the reliability of a smartphone-based electrocardiography device in the measurement of QT and corrected QT intervals in children. METHODS: In all participants, 10-s smartphone electrocardiography tracing from AliveCor device and a standard 12-lead electrocardiograph were obtained simultaneously. Two pediatric electrophysiologists performed the measurements of QT and corrected QT intervals in a blinded manner with Bazett's formula. The results were compared statistically. RESULTS: A total of 285 children (mean age 9.8±4.9 years) who presented to our clinic were included in the study. The mean QT intervals obtained from 12-lead electrocardiographs and AliveCor devices were 343±40 ms and 340±41 ms, respectively. The mean corrected QT intervals obtained from 12-lead electrocardiographs and AliveCor devices were 419±28 ms and 415±33 ms, respectively. There was high correlation between the QT intervals of 12-lead electrocardiographs and AliveCor recordings (Pearson's correlation coefficient: 0.83 [p<0.001]) and significant correlation between the corrected QT intervals of 12-lead electrocardiographs and AliveCor recordings (Pearson's correlation coefficient: 0.57 [p<0.001]). CONCLUSION: AliveCor recordings can accurately detect QT intervals and can potentially be used for the screening of congenital long QT syndrome in children.