Pace-Pacing and Clinical Electrophysiology最新文献

Introduction: Systemic sclerosis (SSc) is a rare connective tissue disease characterized by immune dysfunction, vascular damage, and fibrosis affecting the skin and multiple internal organs, such as the cardiovascular and respiratory systems. In some women with preexisting SSc, pregnancy is associated with negative maternal outcomes. Tachyarrhythmia is a common clinical manifestation of cardiovascular damage in SSc patients. However, few studies have reported the use of catheter ablation and an implantable cardioverter defibrillator (ICD) in patients with SSc complicated by ventricular tachycardia (VT).

Case: A 19-year-old woman known case of SSc referred to our center with recurrent VT during pregnancy and after delivery. Two-dimensional Echocardiogram showed severe systolic dysfunction with a left ventricular ejection fraction (LVEF) of 30%. Considering, recurrent VT despite medical treatment and the progressive nature of systemic sclerosis radiofrequency catheter (RF) ablation and ICD implantation were performed.

Conclusion: We report a case of systemic sclerosis complicated by VT and left ventricular (LV) dysfunction during pregnancy that was successfully treated with RF ablation.

3DQRSarea is a strong marker for cardiac resynchronization therapy and can be obtained by taking the (i) summation or the (ii) difference of the areas subtended by positive and negative deflections in X, Y, Z vectorcardiographic electrocardiogram (ECG) leads. We correlated both methods with the instantaneous-absolute-3D-voltage-time-integral (VTI_QRS-3D). 3DQRSarea consistently underestimated the VTI_{QRS -3D}, but the summation method was a closer and more reliable approximation. The dissimilarity was less apparent in left bundle branch block (r² summation .996 vs. difference .972) and biventricular paced ECGs (r² .996 vs. .957) but was more apparent in normal ECGs (r² .988 vs. .653).

Background: To preserve the benefit of atrial sensing without the implantation of an additional lead, a single-lead ICD system with a floating atrial dipole (DX ICD) has been developed. The purpose of this nationwide survey was to provide an overview of the current key influences of device selection focusing on DX ICD and to test the applicability of a previously published decision-making flowchart of ICD-type selection.

Methods: An online questionnaire was sent to all implanting centers in Hungary. Eleven centers reported data from 361 DX ICD and 10 CRT-DX systems implantations between February 2021 and May 2023.

Results: The most important influencing clinical factors indicated by the participating doctors were elevated risk of atrial fibrillation (AF)/stroke (56%), risk of sinus/supraventricular tachycardias (SVT) (42%), and a potential need for CRT upgrade in the future (36%). The DX ICD was considered in the majority of cases instead of the VVI system (87%), and only in a small proportion instead of a DDD ICD (13%). 60% of the patients with DX ICDs were also included into remote monitoring-based follow-up. In 83% of the cases, good (>2 mV) or excellent (>5) atrial signal amplitude was recorded within 6 weeks after the implantation.

Conclusion: In the current national survey, the most important influencing factors indicated by the implanters for selecting a DX ICD were the elevated risk of stroke or sinus/SVT and a potential need for CRT upgrade in the future. These findings support the use of a previously published decision-making flowchart.

An 80-year-old man with a history of complete heart block underwent dual chamber pacemaker implantation about a year ago. He returned to the hospital due to de novo heart failure caused by pacing-induced cardiomyopathy; hence, we planned to upgrade his pacemaker to a biventricular device. The initial strategy was to perform left bundle branch area pacing-optimized cardiac resynchronization therapy (LOT-CRT) with left bundle branch area pacing (LBBAP) combined with a coronary sinus (CS) lead. In this challenging case, the successful placement of a CS lead was hindered by a complicated combination of a large CS body linked to the left superior vena cava and a winding CS branch. However, utilizing readily available tools, such as the coronary balloon and Guide Plus II ST catheter, proved instrumental in overcoming these obstacles. As a result, LOT-CRT provided the patient with a safe alternative to surgical LV lead placement.

Debranching thoracic endovascular aortic repair may disturb the implantation of a cardiac implantable electronic device in the anterior thoracic region. In case 1, the bypass graft between the right axillary artery, left axillary artery, and left common carotid artery disturbed pacemaker implantation from the left anterior thoracic region. Therefore, right-sided implantation was selected. By contrast, in case 2, the bypass graft between axillary arteries in the anterior thoracic region was visible on fluoroscopy, and we performed conventional left-sided pacemaker implantation with extra-thoracic puncture. The pacemaker implantations were successful in both cases. The implantation strategies were affected by the number of debranched arteries and visibility of the bypass graft.

We report a 5-year-old girl with transient complete atrioventricular (AV) block following surgical closure of a symptomatic conoventricular ventricular septal defect (VSD) which recovered on post-operative day 9. She later presented with exertional dizziness and fatigue. While congenital cardiac defect repairs are occasionally complicated by complete heart block, this patient was found to have intra-Hisian Wenckebach which is rare in the pediatric population and can be very difficult to discern from surface electrocardiograms and by Holter monitoring. Mechanisms of post-surgical AV block, including intra-Hisian Wenckebach, are not well characterized in the pediatric population.

Permanent junctional reciprocating tachycardia (PJRT) is a rare supra ventricular tachycardia (SVT) due to an accessory pathway (AP), characterized by slow and decremental retrograde conduction, which is predominantly seen in infants and children. Although the typical site of AP in PJRT is a right posteroseptal region around or just within the coronary sinus (CS), atypical sites of AP have been described. We report a rare case of PJRT in a 7-year-old girl with an AP located in the superio-paraseptal (Para-Hsian) region that was successfully ablated through a non-coronary sinus.

Background: Electromagnetic interference (EMI) encompasses electromagnetic field signals that can be detected by a device's circuitry, potentially resulting in adverse effects such as inaccurate sensing, pacing, device mode switching, and defibrillation. EMI may impact the functioning of Cardiac Implantable Electronic Devices (CIEDs) and lead to inappropriate therapy.

Method: An experimental measuring device, a loop antenna mimicking the implantable cardioverted defibrillator (ICD) antenna, was developed, and validated at the US Food and Drug Administration (FDA) and sent to Wright State University for testing. Two sets of measurements were conducted while the vehicle was connected to a 220-Volt outlet with charging at ON and OFF. Each measurement set involved three readings at various locations, with the antenna oriented in three different positions to account for diverse patient postures. The experiment utilized a Tesla Model 3 electric vehicle (EV), assessing scenarios both inside and outside the car, including the driver's seat, driver's seat floor, passenger's seat, rear seat, rear seat floor, cup holder, charging port (car), and near the charging station.

Results: The detected voltage (max 400 to 504 millivolts) around the cup holder inside the car differed from all other measurement scenarios.

Conclusion: The investigation highlights the identification of EMI signals originating from an EV) that could potentially interrupt the functionality of a Subcutaneous Implantable Cardioverter-Defibrillator (S-ICD). These signals fell within the R-wave Spectrum of 30-300 Hz. Further in-vivo studies are essential to determine accurately the level of interference between S-ICDs and EMI from Electric Vehicles.

Introduction: While right ventricular pacing (RVP) is the conventional temporary pacing modality used for transcatheter aortic valve replacement (TAVR), this approach possesses inherent risks and procedural challenges. We aim to assess and compare the safety and efficacy of left ventricular pacing (LVP) and RVP during TAVR and balloon aortic valvuloplasty (BAV).

Methods: Following PRISMA guidelines, a comprehensive literature search was conducted in four databases from inception to December 15th, 2023. We included observational studies and clinical trials comparing LVP with RVP during TAVR and BAV procedures. Primary outcomes included short-term mortality, mortality due to cardiac tamponade, and procedural complications including bleeding, vascular complications, and cardiac tamponade. Secondary outcomes comprised procedure duration and length of hospital stay.

Results: Five studies involving 830 patients with RVP and 1577 with LVP were included. Short-term mortality was significantly higher in the RVP group (RR 2.32, 95% CI: [1.37-3.93], P = .002), as was the incidence of cardiac tamponade (RR 2.19, 95% CI: [1.11-4.32], P = .02). LVP demonstrated shorter hospital stays (MD = 1.34 d, 95% CI: [0.90, 1.78], P < .001) and reduced procedure duration (MD = 7.75 min, 95% CI: [5.08, 10.41], P < .00001) compared to RVP. New pacemaker implantation was higher in the RVP group (RR 2.23, 95% CI: [1.14, 4.39], P = .02).

Conclusion: LVP during TAVR and BAV emerges a safer alternative to RVP, offering reduced mortality, hospital stays, and procedure durations.

Objective: To investigate the role of protein kinase C (PKC) in action potential duration (APD) restitution and ventricular tachyarrhythmias (VAs).

Methods and results: Rabbits hearts were isolated and prepared for Langendorff perfusion technique. The stimuli-extra-stimulus (S₁-S₂) method and dynamic S₁ pacing protocol were performed to construct APD restitution and to induce APD alternans or VA, respectively, at 10 sites throughout the ventricular chamber. Administration of phorbol-12-myristate-13-acetate (PMA) (100 nM) (n = 15) greatly steepened the restitution curves (S_max > 1) (p < .01) at each site compared to the control group (n = 15). Furthermore, treatment with PMA also induced larger spatial dispersions of S_max (p < .05) and decreased the thresholds of the VA and APD alternans (p < .01). However, perfused with the PKC inhibitor, bisindolylmaleimide (BIM) (500 nM) (n = 10), reversibly flattened the APD restitution curves at each site (S_max < 1), decreased the spatial dispersions of S_max, and increased the thresholds of APD alternans and VA. According to the results of patch-clamp, peak amplitude of L-type Ca²⁺ current was significantly increased by addition of PMA compared with control (CTL) group (p < .05). Antagonize this current with verapamil (n = 10) can fully inhibited the PMA induced increasing of S_max and inducibility of VA and alternans.

Conclusion: PKC activation increased the dispersion of APD restitution and thus led to occurrence of VA, which possibly related to the increased Ca²⁺ influx.