Electrophysiology Suite Research Articles

Hybrid Epicardial Ventricular Ablation for Arrhythmogenic Right Ventricular Cardiomyopathy

Arrhythmogenic right ventricular cardiomyopathy (ARVC) causes progressive fibro-fatty infiltration of the right ventricle (RV) and is associated with ventricular arrhythmias (VA). The disease progresses from the subepicardium to subendocardium; thus. epicardial ablation improves outcome in patients with recurrent VA. When percutaneous epicardial ablation is unsuccessful, a surgical approach may be required. Limited data are available for minimally invasive hybrid surgical-catheter techniques. Case: A 28-year-old man with ARVC presented with recurrent VA refractory to medical therapy following COVID-19 infection and underwent endocardial ablation with attempted epicardial ablation. He had nine or more different inducible VA morphologies at this study. Epicardial access was unsuccessful due to adhesions. Minimally invasive surgical access for epicardial ablation was scheduled as a multidisciplinary procedure in the electrophysiology suite. A left thoracoscopic approach provided intrapericardial access. Surgical ports were used to facilitate catheter placement and mapping. Relevant clinical arrhythmias were targeted, and substrate modification was performed. The patient was discharged the following morning. No subjective symptoms or implanted-device defibrillation has been required post procedure. Combined surgical and catheter-based approaches for ARVC ablation are safe and feasible. Multidisciplinary team collaboration is key for case planning and success.

Temporary mechanical circulatory support devices: practical considerations for all stakeholders.

Originally intended for life-saving salvage therapy, the use of temporary mechanical circulatory support (MCS) devices has become increasingly widespread in a variety of clinical settings in the contemporary era. Their use as a short-term, prophylactic support vehicle has expanded to include procedures in the catheterization laboratory, electrophysiology suite, operating room and intensive care unit. Accordingly, MCS device design and technology continue to develop at a rapid pace. In this Review, we describe the functionality, indications, management and complications associated with temporary MCS, together with scenario-specific utilization, goal-directed development and bioengineering of future devices. We address various considerations for the use of temporary MCS devices in both prophylactic and rescue scenarios, with input from stakeholders from various cardiovascularspecialties, including interventional and heart failure cardiology, electrophysiology, cardiothoracic anaesthesiology, critical care and cardiac surgery.

Assessment of Arrhythmia Burden through the Use of an Implantable Cardiac Monitor in Patients with a Continuous Flow Left Ventricular Assist Device

The benefit of an ICD in patients with an LVAD remains unclear. There is a growing number of patients with LVADs who do not have concomitant ICDs and therefore implantable cardiac monitors (ICMs) are being used to monitor arrhythmia burden. We report our series of LVAD patients who underwent ICMs for long-term heart rhythm monitoring. We aim to (1) evaluate the burden of atrial and ventricular arrhythmias in patients with a LVAD following ICM implant and (2) to determine whether the ICM generated data results in interventions. Patients were recruited from the University of Rochester Advanced Heart Failure Service. All ICMs were implanted in the electrophysiology suite using standard sterile techniques. All patients were enrolled into remote ICM monitoring. Implantable cardiac monitors were implanted in 10 LVAD patients who did not already have an ICD. No ICM implant procedure related adverse events occurred. Adequate and interpretable signals were obtained from each ICM (9 Medtronic Reveal LINQs, 1 Biotronik BioMonitor) (Figure) with no appreciable artifact. Indications for ICM implant varied, and included documented tachyarrhythmia (VT and/or AF), syncope and presyncope (Table). During long-term monitoring (mean of 357.2 days), 4 patients (40%) had arrhythmia detected on ICM, with an average of 47.5 days to first arrhythmia detected. Decision was made to adjust medication therapy in all 4 of these patients and to implant an ICD in 2 patients (20%) due to ICM detected sustained VT resulting in compromised VAD function. In select LVAD patients, use of an ICM may be used to further risk stratify patients at high risk for ventricular arrhythmias and for whom an ICD implant may confer long term benefit. With observational data showing no survival benefit for ICD therapy in patients with continuous flow LVADs, ICMs may help guide therapy in patients without concomitant ICD. Future studies with larger sample size are warranted.

Minimizing Radiation in the Modern Electrophysiology Laboratory.

Historically, the electrophysiology laboratory has relied heavily on the use of ionizing radiation in the form of fluoroscopy for a broad range of interventions and diagnostics. As the harmful effects of radiation have become increasingly recognized and procedural technologies have advanced, electrophysiologists have adopted new workflows. The purpose of this article is to review the available literature and experience in minimizing radiation in the modern electrophysiology laboratory. This review first covers general approaches to reducing fluoroscopy radiation in the electrophysiology suite, with concepts that apply across all procedure types. These include the reduction of infrared emission through fastidious fluoroscopy settings, new and proven solutions for radiation shielding, and methods of creating distance between the radiation source and the operator to reduce exposure. Following this discussion, we review specific task-based techniques for reducing radiation during special electrophysiologic procedures and workflows such as vascular access, coronary sinus lead placement, catheter manipulation, and periprocedural planning studies.

Transvenous Lead Extraction: A Clinical Commentary for Anesthesiologists

With increasing use of cardiovascular implantable electronic devices, the need for lead extractions has increased to an annual volume of more than 10,000 extractions worldwide. This article provides a focused clinical commentary on the perioperative management, identification, and treatment of life-threatening complications associated with lead extractions. In addition, a summary of indications, techniques, and lead extraction complications is provided. Although uncommon, lead extractions are associated with a consistent rate of major procedure-related complications and mortality. Major life-threatening complications include vascular laceration, cardiac avulsion, hemothorax, pericardial effusion, and cardiac arrest. Comprehensive preoperative risk assessment and adequate planning and preparedness are crucial to decreasing all procedure-related adverse events. The location of the procedure (electrophysiology suite v hybrid operating room) and the nature of cardiac surgical backup are determined after meticulous risk stratification. In addition to decisions on vascular access, invasive monitoring, and modality of rhythm support, transesophageal echocardiography plays a crucial role in early diagnosis, timely management, and potential prevention of these complications.

Adenosine and Bronchospasm: Vigilance in the Electrophysiology Suite

Adenosine and Bronchospasm: Vigilance in the Electrophysiology Suite

Automated, in-vivo, whole-cell electrophysiology using an integrated patch-clamp amplifier

Whole-cell patch clamp recordings of neuronal activity in vivo exhibit signal quality sufficient to report synaptic and ion channel-mediated subthreshold events of importance for understanding neural processing during normal as well as drug-mediated behavior. Recently, we developed a prototype robot [1] that enables automated whole-cell patch clamp recording of neurons in a living mouse brain. While automation of the in-vivo patch clamping process opens up the possibility of multi-channel in vivo electrophysiology, scaling up the current system would dramatically increase system cost and complexity. Specifically, the current autopatching algorithm relies on several discrete pieces of hardware such as an amplifier, headstage and digitizer--as well as commercial software to communicate with the equipment and perform electrophysiology. We will present an automated, in-vivo, whole cell electrophysiology suite that consists of a four-channel microchip-based patch clamp amplifier [2] and software that dramatically simplifies the setup necessary for traditional automated patch clamping. This system (Figure ​(Figure1A)1A) eliminates the need for the conventional amplifier, digitizer, headstage, and data acquisition board to effectively combine the high-throughput nature of the autopatcher [1] with the voltage and current clamp toolsets available in commercial software packages. Un-automated in vivo whole-cell recordings have already been demonstrated using a single-channel microchip-based patch clamp amplifier with conventional pCLAMP software (Molecular Devices, Sunnyvale, CA; Figure ​Figure1B).1B). Preliminary results indicate that our simpler, multi-channel electrophysiology suite can perform computations required for automatic neuron detection, leading to successful whole-cell patches. We will report progress toward total automated integration and incorporation of electrophysiology tools into the software suite. The total cost required for the patch chip and the electrophysiology software suite should be several orders of magnitude less than that of conventional systems, and far simpler to handle, integrate with existing rigs, and use. Figure 1 (A) Single-channel patch chip amplifier in the patch clamping setup. (B) Representative in vivo whole-cell recordings in current clamp mode using conventional pCLAMP software and the patch chip.

Airway Trauma in a High Patient Volume Academic Cardiac Electrophysiology Laboratory Center

Providing anesthesia and managing airways in the electrophysiology suite can be challenging because of its unique setting outside of the conventional operating room. We report our experience of several cases of reported airway trauma including tongue and pharyngeal hematoma and vocal cord paralysis in this setting. We analyzed all of the reported airway trauma cases between December 2009 and January 2011 in our cardiac electrophysiology laboratories and compared these cases with those without airway trauma. Data from 87 cases, including 16 cases with reported airway trauma (trauma group) and 71 cases without reported airway trauma from the same patient population pool at the same period (control group), were collected via review of medical records. Airway trauma was reported for 16 patients (0.7%) in 14 months among 2434 anesthetic cases. None of these patients had life-threatening airway obstruction. The avoidance of muscle relaxants during induction in patients with a body mass index less than 30 was found to be a significant risk factor for airway trauma (P = 0.04; odds ratio, 10; 95% confidence interval, 1.1-482). Tongue or soft tissue bite occurred in 2 cases where soft bite block was not used during cardioversion. No statistically significant difference was found between the trauma and the control groups for preprocedure anticoagulation, anticoagulation during the procedure, or reversal of heparin at the end of the procedure. The overall incidence of reported airway trauma was 0.7% in our study population. Tongue injury was the most common airway trauma. The cause seems to have been multifactorial; however, airway management without muscle relaxant emerged as a potential risk factor. Intubation with muscle relaxant is recommended, as is placing a soft bite block and ensuring no soft tissue is between the teeth before cardioversion.

Development of a non-linear optical microscope for real-time measurement of neuronal activity in sub-micrometric structures

To address the actual challenges in neuroscience, such as real-time voltage-sensing of sub-micrometric structures like dendritic spines and multi-modal and functional imaging of cultured neurons and brain slices, we developed a dedicated instrument which offers high-performance imaging combined with a complete electrophysiology suite. For instance, it allows full-frame imaging at rates larger than 5 frames per second with a diffraction-limited resolution, excitation over a wide spectral range (680–1320 nm), optimized signal-to-noise ratio and targeted-path scanning abilities. Thanks to this setup, new optical sensing probes are under study, with encouraging preliminary results.

The ‘dark’ side of sedation: 12 years of office‐based pediatric deep sedation for electroretinography in the dark

Analyze pediatric ERG data for adverse events, interventions, and outcomes of propofol sedations performed in near-complete darkness. To demonstrate that deep sedation with propofol for ERG can be performed efficiently and safely in children in near-total darkness. Full-field electroretinography (ERG) is a valuable tool for the diagnosis of vision loss in children. The ERG measures the electrical activity of the retina. In children, ERG quality significantly improves with deep sedation by allowing easier eye electrode placement and decreasing motion artifacts. As this procedure must be performed in darkness, administering sedation imposes unique challenges. ERGs are performed outside of the operating room in our hospital's electrophysiology suite. IVs are placed, and patients are allowed to adapt to complete darkness. An anesthesiologist then administers propofol sedation in the dark with the aid of a red-filter light source and monitor light shields. Data were collected on 379 patients (411 ERGs) performed from 1996 to 2008. These records were reviewed and analyzed for demographic, medical, and anesthetic data. Propofol sedation resulted in an ERG completion rate of 99.5%. During sedation, 8.5% (35) of patients experienced minor respiratory complications such as airway obstruction that resulted in an oxygen saturation <90%. A total of 9.7% (40) of patients required minor airway interventions such as a chin lift. We demonstrated that pediatric sedation is a safe, efficient, and a cost-effective method for measuring ERGs in a challenging environment. The incidence of minor complications is low and appears similar to other studies of propofol sedation.

Anticipation of Radiation Dose to the Conceptus from Occupational Exposure of Pregnant Staff During Fluoroscopically Guided Electrophysiological Procedures

Conceptus dose from occupational exposure. A female employee working in the electrophysiology suite has the right to know potential radiation hazards to the unborn child before she is pregnant or before she decides to formally declare her pregnancy. Moreover, the employer of a declared pregnant worker must evaluate the work situation and ensure that the conceptus dose is kept below the maximum permissible level during the remaining gestation period. The aim of this study was to develop a method for conceptus dose anticipation and determination of maximum workload allowed for the pregnant employee who participates in fluoroscopically guided electrophysiological procedures. A C-arm fluoroscopy system, an anthropomorphic phantom, and a radiation meter were used to obtain scattered air kerma dose rates separately for each of the three fluoroscopic projections typically used in the electrophysiology suite. Air kerma to conceptus dose conversion factors for all trimesters of gestation were calculated using Monte Carlo simulation. A formula is presented for the anticipation of the conceptus dose from occupational exposure of pregnant staff during fluoroscopically guided electrophysiological procedures. Normalized data are provided for conceptus dose estimation from occupational exposure of pregnant staff working in any electrophysiology laboratory. A methodology for estimation of maximum workload allowed for each month of the remaining gestation period of a worker who declared her pregnancy is proposed, which ensures that the regulatory dose limits are not exceeded. Data presented may be used for the implementation of a radiation protection program designed for pregnant staff working in an electrophysiological suite.