key: cord-0686876-5mz8ohb4
authors: Sinha, Sunil K.; Akinyele, Bolanle; Spragg, David D.; Marine, Joseph E.; Berger, Ronald; Calkins, Hugh; Love, Charles J.
title: Managing Cardiac Implantable Electronic Device Patients during a Health Care Crisis: Practical Guidance
date: 2020-05-19
journal: Heart rhythm O2
DOI: 10.1016/j.hroo.2020.05.005
sha: 9a82e255a0168f06a69e0a371b5233d0b72d4792
doc_id: 686876
cord_uid: 5mz8ohb4

Abstract Our world is faced with a global pandemic that threatens to overwhelm many national health care systems for a prolonged period. Consequently, the elective long-term CIED management of millions of patients is potentially compromised raising the likelihood of patients experiencing major adverse events due to loss of CIED therapy. This review gives practical guidance to health care providers to help promptly recognize the requirement for expert consultation for urgent interrogation and/or surgery in CIED patients.

Practical Guidance 50 Introduction 52 The high infectivity and fatality rates of the novel COVID-19 virus has triggered a global 53 pandemic that is unprecedented in the modern medical era. 1 As a result, many medical and 54 public health experts predict that a number of national health systems could be overwhelmed for 55 an uncertain period of time. [2] [3] Fortunately, many clinics and emergency departments are still 56 able to maintain their remote cardiac implantable electronic device (CIED) monitoring capability 57 as off-site telecommuting is usually feasible. 4 Unfortunately, many health care providers that 58 electively manage CIED patients are being redirected to assist in other areas of immediate 59 clinical need and elective CIED surgeries have been temporarily suspended at many medical 60 centers. [4] [5] Simultaneously, mandates for social distancing are leading to cancellation of 61 ambulatory CIED outpatient appointments for those patients not enrolled in remote monitoring 62 and, in most circumstances, absence of manufacturer field representatives for clinical support.

Accordingly, recommended approaches for the long-term management of many CIED patients 64 are potentially compromised raising the risk of major adverse events in patients that may suffer 65 an untimely loss of CIED therapy.

This brief review gives practical guidance to health care providers of CIED patients for 67 appropriate identification of CIED type and manufacturer and prompt determination for expert 68 consultation for urgent interrogation and/or surgery.

Electronic medical records will usually detail a patient's CIED type (pacemaker or implantable 72 cardioverter-defibrillator) and manufacturer in relevant cardiac notes. In the absence of medical 73 records, many patients will be aware of their CIED type and manufacturer or possess a Table 1 ECGs usually indicates that a patient is not "pacemaker dependent". When pacing artifact is 93 observed in a patient requiring demand pacing for bradycardia or cardiac resynchronization 94 therapy, the ECG can be studied for evidence of malfunction due to lack of sensing, lack of 95 capture, and/or battery depletion. 8-10 When available, an ECG performed with a "doughnut 96 magnet" over the pacemaker generator will yield an asynchronous mode (DOO or VOO) with a 97 fixed pacing rate that accurately reflects the battery status for that specific manufacturer and thus 98 can identify a pacemaker at elective replacement indication (ERI, also termed elective 99 replacement time -ERT or recommended replacement time -RRT). 8 When power-on reset (also 100 termed "electrical reset", "safety mode", "standby mode" and "safe program") occurs due to a 101 potentially critical loss of component integrity in the pacemaker's central processing unit the 102 ECG will demonstrate reversion to high output back-up VVI pacing with very prominent 103 unipolar pacing artifact at a fixed rate. 8 The manufacturer-specific characteristics seen due to 104 low battery status and power-on reset for the five largest pacemaker manufacturers are 105 summarized in Table 2 .

In lieu of remembering much of the tabulated data in Table 2 one can utilize the simple "Rules of 107 Ten": Atrial pacing at a rate not a multiple of ten or non-synchronous ventricular pacing at a rate 108 not a multiple of ten on a resting ECG likely indicates pacemaker battery depletion and/or 

As with pacemakers the standard 12 lead ECG can be utilized to assess pacing status in those 118 implantable cardioverter-defibrillator (ICD) recipients that require demand pacing for 119 bradycardia or cardiac resynchronization therapy. Of note, a doughnut magnet placed over the 120 ICD generator will not alter pacing mode but will inhibit delivery of ICD shocks when they are 121 deemed inappropriate or prior to emergent thoracic surgery requiring electrocautery. For a key summary of these practical guidance tips and a step wise algorithm for health care 134 providers for appropriate identification of CIED type and determination for expert consultation 135 for urgent interrogation and/or surgery, please see Figure 1 .

We are now challenged with caring for CIED patients in an unprecedented public health care 139 crisis where many routine approaches to management are less feasible. We hope that the basic 140 practical guidance in this review will assist health care providers in promptly caring for CIED 141 patients at greatest risk. 

Responding to Covid-19 -A Once-in-a-Century Pandemic?

Critical Supply Shortages -The Need for Ventilators and Correctly Identify CIED (consider "Pacemaker-ID" smart phone app) Pacemaker: Syncope, Palpitations, Dyspnea or CIED infection? Resting ECG (apply the "Rules of Ten") and CIED Interrogation* ± Cardiac EP consult † ICD: Syncope, Palpitations, Dyspnea or CIED infection? Shock or Alarm?

CIED (pacemaker or implantable cardioverter-defibrillator (ICD)) type and manufacturer model can be identified by patient recollection, medical records, manufacturer cards, manufacturer registries, and by chest X-ray utilizing the "Pacemaker-ID" smart phone application

A resting standard 12 lead ECG can provide data on a patient's intrinsic heart rhythm, pacing status and efficacy. The "Rules of Ten" can help screen for pacemaker battery depletion or power-on reset in the majority of pacemaker manufacturers

Application of a "doughnut magnet" over the generator will maintain asynchronous pacing at a fixed rate in all pacemaker models. Magnet application will maintain inhibition of shocks in all ICD models

Most cardiac clinics and hospital emergency rooms have capability for remote CIED interrogation. However, CIED programming cannot be performed remotely

Pacemaker or ICD patients with new onset cardio-respiratory symptoms or CIED infection (also auditory/vibratory alarms in ICD patients) warrant interrogation and potential expert consultation if programming or surgery may be required

†Medtronic models manufactured since 2013 preserve programmed mode at Recommended Replacement Time (RRT) 3 months prior to Elective Replacement Indication (ERI). **Magnet application at RRT/ERI in Medtronic models manufactured prior to 2013 initiates a "threshold margin test" (3 paced impulses at 100 bpm with a 20% decrease in amplitude on the third impulse) followed by pacing at 65 bpm.