Acute effects of radiofrequency ablation of atrial arrhythmias on implanted permanent pacing systems

Safety of catheter ablation in patients with recently implanted cardiac implantable electronic device: A 5-year experience

INTRODUCTION

Catheter ablation (CA) can interfere with cardiac implantable electronic device (CIED) function. The safety of CA in the 1st year after CIED implantation/lead revision is uncertain.

METHODS

This single center, retrospective cohort included patients who underwent CA between 2012 and 2017 and had a CIED implant/lead revision within the preceding year. We assessed the frequency of device/lead malfunctions in this population.

RESULTS

We identified 1810 CAs in patients between 2012 and 2017, with 170 CAs in 163 patients within a year of a CIED implant/lead revision. Mean age 68 ± 12 years (68% men). Time between the CIED procedure and CA was 158 ± 99 days. The CA procedures included AF ablation (n = 57, 34%), AV node ablation (n = 40, 24%), SVT ablation (n = 37, 22%), and PVC/VT ablations (n = 36, 21%). The cumulative frequency of lead dislodgement, significant CIED dysfunction, and/or CIED-related infection following CA was (n = 1/170, 0.6%). There was a single atrial lead dislodgement (0.6%). There were no instances of power-on-reset or CIED-related infection. Following CA, there was no significant difference in RA or RV lead sensing (p = 0.52 and 0.84 respectively) or thresholds (p = 0.94 and 0.17 respectively). The RA impedance slightly decreased post-CA from 474 ± 80 Ohms to 460 ± 73 Ohms (p = 0.002), as did the RV impedance (from 515 ± 111 Ohms to 497 ± 98 Ohms, p < 0.0001).

CONCLUSIONS

CA can be performed within 1 year following CIED implantation/lead revision with a low risk of CIED/lead malfunction or lead dislodgement. The ideal time to perform CA after a CIED remains uncertain.

Radiofrequency Denervation of the Spine and the Sacroiliac Joint: A Systematic Review based on the Grades of Recommendations, Assesment, Development, and Evaluation Approach Resulting in a German National Guideline

STUDY DESIGN

Systematic review of the literature and subsequent meta-analysis for the development of a new guideline.

OBJECTIVES

This manuscript summarizes the recommendations from a new clinical guideline published by the German Spine Society. It covers the current evidence on recommendations regarding the indication, test blocks and use of radiofrequency denervation. The guidelines aim is to improve patient care and efficiency of the procedure.

METHODS

A multidisciplinary working group formulated recommendations based on the Grades of Recommendations, Assessment, Development, and Evaluation (GRADE) approach and the Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument.

RESULTS

20 clinical questions were defined for guideline development, with 87.5% consensus achieved by committee members for one recommendation and 100% consensus for all other topics. Specific questions that were addressed included clinical history, examination and imaging, conservative treatment before injections, diagnostic blocks, the injected medications, the cut-off value in pain-reduction for a diagnostic block as well as the number of blocks, image guidance, the cannula trajectories, the lesion size, stimulation, repeat radiofrequency denervation, sedation, cessation or continuation of anticoagulants, the influence of metal hardware, and ways to mitigate complications.

CONCLUSION

Radiofrequency (RF) denervation of the spine and the SI joint may provide benefit to well-selected individuals. The recommendations of this guideline are based on very low to moderate quality of evidence as well as professional consensus. The guideline working groups recommend that research efforts in relation to all aspects of management of facet joint pain and SI joint pain should be intensified.

Acute pacing threshold elevation during simultaneous Micra leadless pacemaker implantation and AV node ablation: Clinical cases, computer model and practical recommendations

BACKGROUND

In patients with refractory atrial fibrillation (AF), atrioventricular nodal (AVN) ablation and permanent pacemaker implantation is recommended. The Micra Transcatheter Pacing System (Micra) is a single chamber leadless pacemaker (LPM) and thus offers the possibility of AV node (AVN) ablation in the same procedure. Pacing threshold (PT) elevation after radiofrequency (RF) ablation is a potential complication.

METHODS

We conducted a single center retrospective cohort study. Patients implanted with a Micra (n = 84) and concomitant or delayed AVN ablation (n = 12) from 2014 to 2022 were included. Two cases of acute Micra PT elevation immediately following RF AVN ablation required device retrieval and implantation of a new Micra. Procedural characteristics and electrophysiological parameters were analyzed, and a computer model was performed to determine factors responsible for acute PT elevations.

RESULTS

A total of 84 patients were included. Mean age was 74 ± 10 and 48% were women. Twelve patients (14%) underwent AVN ablation. Two patients had acute PT elevation requiring device retrieval despite no direct contact of the ablation catheter with the Micra. Computer modeling shows that significant dissipated power due to electrical field coupling can occur at the tip or ring electrode if the catheter is not kept at a safe distance (≥35 mm) from the Micra when a maximum power of 100 W is delivered.

CONCLUSION

Concurrent AVN ablation and Micra implantation is safe in most patients. To prevent acute PT elevation, keeping a safe distance of ≥35 mm from the tip and ring electrodes of the Micra and using lower power output may prevent this complication.

Perioperative Management of Patients with Cardiac Implantable Electronic Devices and Utility of Magnet Application

With the demographic evolution of the population, patients undergoing surgery today are older and have an increasing number of sometimes complex comorbidities. Cardiac implantable electronic devices (CIED) are also getting more and more complex with very sophisticated programming algorithms. It may be generally assumed that magnet application reverts pacing to an asynchronous mode in pacemakers and disables tachycardia detection/therapy in internal cardioverter-defibrillators. However, depending on device type, manufacturer and model, the response to magnet application may differ substantially. For these reasons, perioperative management of CIED patients is getting more and more challenging. With this review article we provide an overview of optimal perioperative management of CIED patients with a detailed description of CIED response to magnet application depending on manufacturer and device-type, which may help in providing a safe perioperative management plan for the CIED patient.

Practice Advisory for the Perioperative Management of Patients with Cardiac Implantable Electronic Devices: Pacemakers and Implantable Cardioverter–Defibrillators 2020

This practice advisory updates the “Practice Advisory for the Perioperative Management of Patients with Cardiac Implantable Electronic Devices: Pacemakers and Implantable Cardioverter–Defibrillators: An Updated Report by the American Society of Anesthesiologists Task Force on Perioperative Management of Patients with Cardiac Implantable Electronic Devices,” adopted by the American Society of Anesthesiologists in 2010 and published in 2011. This updated advisory is intended for use by anesthesiologists and all other individuals who deliver or who are responsible for anesthesia care. The update may also serve as a resource for other physicians and healthcare professionals who manage patients with cardiac implantable electronic devices.

Supplemental Digital Content is available in the text.

Long-term efficacy and safety of radiofrequency catheter ablation of atrial fibrillation in patients with cardiac implantable electronic devices and transvenous leads

INTRODUCTION

Long-term efficacy and safety are uncertain in patients with cardiac implantable electronic devices (CIED) and transvenous leads (TVL) undergoing radiofrequency catheter ablation of atrial fibrillation (AF). Thus, we assessed the outcome of AF ablation in those patients during long-term follow-up using continuous atrial rhythm monitoring (CARM).

METHODS AND RESULTS

A total of 190 patients (71.3 ± 10.7 years; 108 (56.8% men) were included in this study. At index procedure 81 (42.6%) patients presented with paroxysmal AF and 109 (57.4%) with persistent AF. The ablation strategy included pulmonary vein isolation in all patients and biatrial ablation of complex fractionated electrograms with additional ablation lines, if appropriate. AF recurrences were assessed by CARM- and CIED-related complications by device follow-up. After a mean follow-up of 55.4 ± 38.1 months, freedom of AF was found in 86 (61.4%) and clinical success defined as an AF burden less than or equal to 1% in 101 (72.1%) patients. Freedom of AF was reported in 74.6% and 51.9% (P = 0.006) and clinical success in 89.8% and 59.3% (P < 0.001) of patients with paroxysmal and persistent AF, respectively. In 3 of 408 (0.7%) ablation procedures, a TVL malfunction occurred within 90 days after catheter ablation. During long-term follow-up 9 (4.7%) patients showed lead dislodgement, 2 (1.1%) lead fracture, and 2 (1.1%) lead insulation defect not related to the ablation procedure.

CONCLUSION

Our findings using CARM demonstrate long-term efficacy and safety of radiofrequency catheter ablation of AF in patients with CIED and TVL.

Perioperative management of cardiac rhythm assist devices in ambulatory surgery and nonoperating room anesthesia

PURPOSE OF REVIEW

Patients with cardiac implantable electronic devices (CIEDs) frequently undergo various surgical procedures and in the past perioperative management involved only placing magnet over the device. New programming features, development of implantable cardiac defibrillator (ICD), cardiac resynchronization therapy, and increasing complexity of the operating room equipment have led to new sources of electromagnetic interference (EMI). A comprehensive understanding of the CIED is necessary to provide a timely and optimal care to the patients.

RECENT FINDINGS

Technological advancements and direct implantation of the transvenous implantable cardiac defibrillators into the heart have led to less clear lines between the pacemakers and the ICD. Subcutaneous ICD as well as the leadless transcatheter deployed intracardiac pacemaker development has complicated the issue further.

SUMMARY

Rapidly developing technologies and increasing number of patients with these devices coming for noncardiac surgeries necessitate continuous education of the anesthesia team regarding perioperative management of such devices.

Twitching of the Pacemaker Pocket Induced by Radiofrequency Energy Delivery to the Cavotricuspid Isthmus

An 82-year-old man with a permanent pacemaker (PM) implanted for sick sinus syndrome complained of palpitation due to paroxysmal atrial fibrillation and flutter. During extensive pulmonary vein isolation, the atrial lead was dislodged to the level of the tricuspid annulus. Radiofrequency energy delivery to the cavotricuspid isthmus reproducibly caused twitching of the PM pocket. The atrial lead was repositioned to the right atrial appendage, PM check revealed no functional change in the PM or lead performance. This is the first reported case of twitching of the PM pocket due to electromagnetic interference.

The Effects of Catheter Ablation on Permanent Pacemakers and Implantable Cardiac Defibrillators

Catheter ablation is a procedure that is frequently performed in patients with cardiac implantable electronic devices. Here, we review all of the potential interactions that can occur among patients undergoing catheter ablation while having implantable cardiac electronic devices, and discuss the precautionary measures to minimize such interactions.

Radiofrequency and Cryo-Ablation Effect on Transvenous Pacing and Defibrillatory Lead Integrity: An In Vitro Study

INTORDUCTION

Medical societies and cardiac implantable electronic device (CIED) manufacturers recommend avoiding close or direct contact between the body of transvenous leads and ablation catheters used to treat cardiac arrhythmias. These recommendations are made despite the lack of clinical studies. However, the target myocardium for successful ablation can be contiguous to CIED leads.

METHODS AND RESULTS

We examine in vitro the effects of direct application of radiofrequency (RF) and cryo-ablation energy on the integrity and functionality of CIED leads (excluding the pacing electrodes and defibrillation coils). A saline bath was created to mimic the body milieu. CIED leads, including all commercially available lead insulation materials, were connected to a CIED pulse generator and placed in direct contact with an ablation catheter in the tissue bath. RF and cryo-ablation energy were delivered under various conditions, including maximal ablation power, temperature, and impedance via the RF generator. CIED lead functionality, reflective of conductor integrity, was evaluated through lead impedance monitoring during ablation. CIED leads were then visually inspected, and examined with optic and electron microscopy as per protocol. A total of 42 leads were studied. All leads showed the absence of insulation damage at the site of ablation visually and with microscopy. Lead functionality was also preserved in all leads.

CONCLUSION

Catheter ablation in contact with CIED leads using radiofrequency or cryo-ablation in vitro did not affect lead body integrity and function despite aggressive ablation settings. It may be reasonable to perform ablation in contact with the body of CIED leads when clinically necessary.

Effects of external electrical and magnetic fields on pacemakers and defibrillators: from engineering principles to clinical practice

The overall risk of clinically significant adverse events related to EMI in recipients of CIEDs is very low. Therefore, no special precautions are needed when household appliances are used. Environmental and industrial sources of EMI are relatively safe when the exposure time is limited and distance from the CIEDs is maximized. The risk of EMI-induced events is highest within the hospital environment. Physician awareness of the possible interactions and methods to minimize them is warranted.

Radiofrequency and microwave tumor ablation in patients with implanted cardiac devices: is it safe?

PURPOSE

To identify malfunction of implanted cardiac devices during or after thermal ablation of tumors in lung, kidney, liver or bone, using radiofrequency (RF) or microwave (MW) energy.

MATERIALS AND METHODS

After providing written consent, 19 patients (15 men and 4 women; mean age 78 years) with pacemakers or pacemaker/defibrillators underwent 22 CT image-guided percutaneous RF or MW ablation of a variety of tumors. Before and after each procedure, cardiac devices were interrogated and reprogrammed by a trained cardiac electrophysiology fellow. Possible pacer malfunctions included abnormalities on electrocardiographic (EKG) monitoring and alterations in device settings. Our institutional review board approved this Health Insurance Portability and Accountability Act-compliant study. Informed consent for participation in this retrospective study was deemed unnecessary by our review board.

RESULTS

During 20 of 22 sessions, no abnormalities were identified in continuous, EKG tracings or pacemaker functions. However, in two sessions significant changes, occurred in pacemaker parameters: inhibition of pacing during RF application in one, session and resetting of mode by RF energy in another session. These changes did not, result in hemodynamic instability of either patient. MW ablation was not associated with, any malfunction. In all 22 sessions, pacemakers were undamaged and successfully reset to original parameters.

CONCLUSION

RF or MW ablation of tumors in liver, kidney, bone and lung can be performed safely in patients with permanent intra-cardiac devices, but careful planning between radiology and cardiology is essential to avoid adverse outcomes.

Safety and efficacy of radiofrequency energy catheter ablation of atrial fibrillation in patients with pacemakers and implantable cardiac defibrillators

BACKGROUND

Catheter ablation has significantly transformed the clinical management of atrial fibrillation (AF). The safety and efficacy of this procedure are not well understood in patients with pacemakers and defibrillators.

OBJECTIVES

The purpose of this study was to study the impact of radiofrequency catheter ablation of AF in patients with pacemakers and implantable cardiac defibrillators.

METHODS

We studied 86 patients with pacemakers and defibrillators (group I) and a similar number of age- and gender-matched controls (group II) who underwent AF ablation between 1999 and 2004. Clinical and procedural variables were compared between the two groups. In group I, various generator and lead parameters were compared before and after the procedure. Resurgence of clinical AF after 2 months was considered recurrence.

RESULTS

Both groups were similar with regard to age, gender, body mass index, and type of AF. Group I had a higher incidence of diabetes (17% vs 6%, P = .03), coronary artery disease (25% vs 13%, P = .05), less prolonged AF (31 +/- 21 vs 45 +/- 30 months, P <.001), lower left ventricular ejection fraction (49 +/- 13% vs 52 +/- 9%, P = .03), and left ventricular end-diastolic dimensions (4.97 +/- 0.81 vs 4.72 +/- 0.67, P = .03). No changes in the sensing and pacing thresholds, impedance of atrial and ventricular leads, or defibrillator coil impedance after AF ablation were observed in group I. Atrial lead dislodgment was seen in two patients. Transient abnormal but "expected" pulse generator behavior was seen in 25% of patients without permanent malfunction. Stroke (1% vs 1%, P = 1.000), pulmonary vein stenosis (2% vs 1%, P = .77), and AF recurrence rates at 12 months were similar between groups I and II, respectively (19% vs 21%, P = .73).

CONCLUSION

AF ablation is safe and efficacious in patients with pacemakers and defibrillators.

Percutaneous Radiofrequency Trigeminal Rhizotomy in a Patient with an Implanted Cardiac Pacemaker

Percutaneous radiofrequency ablation is a frequently used treatment for trigeminal neuralgia. Radiofrequency is another potential source of electromagnetic interference to implanted cardiac pacemakers. Our patient had a permanent pacemaker and underwent the procedure without incident.

Radiofrequency treatment of hepatic neoplasms in patients with permanent pacemakers

Clinicians who provide care for patients with implantable devices for rhythm management, ie, pacemakers and internal cardioverter defibrillators, must be aware of sources of interference that could affect device function. Intracardiac radiofrequency is a recognized source of potential interference. However, radiofrequency to extracardiac sites that are relatively close to the implanted device has not been investigated thoroughly. We present 2 patients with permanent pacemakers undergoing intrahepatic radiofrequency for the treatment of metastatic disease. No interference was documented in either patient. Additional in vitro and in vivo studies are needed to determine definite clinical guidelines for such patients.

Safety of pacemaker implantation prior to radiofrequency ablation of atrioventricular junction in a single session procedure

RF current delivery may cause acute and chronic dysfunction of previously implanted pacemakers. The aim of this study was to assess prospectively the effects of RF energy on Thera I and Kappa pacemakers in 70 consecutive patients (mean age 70 +/- 11 years, mean left ventricular ejection fraction 48 +/- 15%) who underwent RF ablation of the AV junction for antiarrhythmic drug refractory atrial fibrillation (permanent in 42 patients, paroxysmal in 28). These pacing systems incorporate protection elements to avoid electromagnetic interference. The pacemakers (Thera DR 7960 I in 20 patients, Thera SR 8960 I in 30, Kappa DR 600-601 in 8, Kappa SR 700-701 in 12) were implanted prior to RF ablation in a single session procedure and were transiently programmed to VVI mode at a rate of 30 beats/min. Capsure SP and Z unibipolar leads were used. During RF application there was continuous monitoring of three ECG leads, endocavitary electrograms, and event markers. Complete AV block was achieved in all cases after 3.6 +/- 2.9 RF pulses and 100 +/- 75 seconds of RF energy delivery. The mean time of pacemaker implantation and RF ablation was 60 +/- 20 minutes. Transient or permanent pacemaker dysfunction including under/oversensing, reversion to a "noise-mode" pacing, pacing inhibition, reprogramming, or recycling were not observed. Leads impedance, sensing, and pacing thresholds remained in the normal range in the acute and long-term phase (average follow-up 18 +/- 12 months). In conclusion, Thera I and Kappa pacemakers exhibit excellent protection against interference produced by RF current. The functional integrity of the pacemakers and Capsure leads was observed in the acute and chronic phases. Thus, the implantation of these pacing systems prior to RF ablation of the AV junction can be recommended.

Interference with cardiac pacing

Most exposures to electromagnetic interference are transient and pose no threat to patients with pacemakers and implantable cardioverter defibrillators. Prolonged exposure may be catastrophic in pacemaker dependent patients. New technologies (wireless phones, electronic antitheft surveillance) are safe if proper precautions are takes. Radiofrequency ablation requires concomitant temporary pacing. MR imaging remains contraindicated in patients with these devices until further study is undertaken.

Effects of radiofrequency catheter ablation on patients with permanent pacemakers

The objective of this study was to assess the effects of radiofrequency energy application on implanted pacemaker functions. Radiofrequency (RF) catheter ablation may cause pacemaker dysfunction due to electromagnetic interferences. The effects of RF on pacemaker behavior were studied in a series of 38 pacemakers, implanted 18 +/- 26 months prior to a RF procedure using either a right ventricular approach (AV node ablation, n = 35) or a left ventricular approach (left concealed accessory pathway ablation, n = 1; VT ablation, n = 2). The 38 patients (mean age 65 +/- 9 years) included 20 men and 18 women. Before energy applications, the 23 different pacemaker models were programmed to the VVI mode at the lowest available rate. The continuous surface ECG was recorded throughout the procedure. Thorough testing of the devices was performed before and after each RF delivery. Unusual pacemaker responses occurred in 20 of the 38 cases studied (53%). The impact of RF delivery was unpredictable, and variable dysfunctions were observed at different times for a given patient or could vary for a given model. Unusual pacemaker responses included pacemaker inhibition (n = 8), untoggled backup mode (n = 3), electromagnetic interference noise mode (n = 3), temporary RF-induced pacemaker tachycardia (n = 2), erratic behavior (n = 1), oversensing of RF onset and offset (n = 8), and transient loss of ventricular capture, (n = 1). Postablation, most devices automatically toggled back to full functionality. The three devices in the untoggled backup mode had to be reprogrammed to obtain normal operations. At the end of the procedure, pacing thresholds remained unchanged in all but one patient, in whom the increase in ventricular threshold was due to a nicked lead. In conclusion, implanted pacemakers frequently exhibit transient, unpredictable responses to RF energy application. Although all pacemaker functions were restored postablation, some devices had to be reset manually. The anomalies observed during the RF application argue for the simultaneous use of an external pacemaker in pacing-dependent patients.