Volume 22, Issue 3 , Pages 341-346, June 2008
Preoperative Evaluations: The Very Last Chance To Identify a Problem With a Pacemaker or Implanted Cardioverter-Defibrillator
Article Outline
IN THIS ISSUE of the Journal, Boriani et al1 report a case of a cardiac pacemaker (PM) lead perforation that extended through the right ventricular free wall and into the patient's left pleural space. Because the patient remained asymptomatic, this perforation was not discovered until during a routine follow-up examination 10 days after the implant. According to the authors, the patient underwent an uneventful repositioning of the lead.
As most readers are aware, permanently implanted devices (PMs and implantable cardioverter-defibrillators [ICDs]) can provide therapy for ventricular bradycardia regardless of cause (sinoatrial node disease, atrial tissue disease, or conduction system disease), significant cardiomyopathy (modalities currently identified as cardiac resynchronization therapy, biventricular pacing, or heart failure pacing), hypertrophic cardiomyopathy (the left bundle-branch block activation pattern results in late depolarization of the septum, with emptying of the ventricle prior to septal movement), neurogenic syncope, carotid sinus syndrome, and long QT syndrome (pacing prevents the long-short-long RR cycles that can precipitate untoward tachyarrhythmias). ICDs also provide therapy for tachyarrhythmias.
These pacing (and defibrillation) devices can malfunction for a variety of reasons without producing “symptoms.” For example, consider the following cases.
Case 1
A 67-year-old man with cerebrovascular and coronary artery disease who had previously undergone operative and PCI revascularization presented for head and neck surgery. He also had undergone dual-chamber PM placement for “bradycardia” 42 months prior. He reported undergoing a telephone check 4 days earlier, and he had undergone an in-office comprehensive PM check 2 months prior. He complained about longstanding palpitations and fatigue, both of which had been attributed to his coronary artery disease and cerebrovascular disease. Interrogation of his PM showed a “high-impedance atrial lead.” A chest film showed a broken atrial lead consistent with subclavian crush syndrome (Fig 1A). Importantly, a chest film obtained from an outside facility taken 18 months prior showed a similar defect, just not as pronounced (Fig 1B). In fact, Figure 1C shows a portion of an electrocardiogram obtained more than 1 year before admission with inappropriate R-on-T pacing caused by atrial lead undersensing. R-on-T pacing has been known to incite serious ventricular arrhythmias.2
Fig 1.
(A) A chest x-ray from a dual-chamber pacing system with a discontinuous atrial lead. This is the natural progression of subclavian crush syndrome. (B) A chest x-ray from the same patient taken 18 months prior showing the onset of subclavian crush syndrome. (C) A portion of a 12-lead electrocardiogram obtained from outside sources for this patient from 13 months prior. The closed, downward arrow shows an R-on-T pace that resulted from blanking while the pacemaker was pacing on the atrial channel. As a result, the spontaneous ventricular depolarization was not sensed (this is functional undersensing), and the pacemaker emitted a ventricular pace 175 milliseconds later. The open, downward arrow shows a paced ventricular event that resulted from undersensing the previous QRS, suggesting a problem with the ventricular lead as well.
Case 2
A 72-year-old man with lung cancer was scheduled for a central catheter placement for chemotherapy. He had a dual-chamber PM implanted 44 months prior. He denied any problems with his PM. His last comprehensive interrogation of the pacing system took place 126 days prior. He reported being told that he would need a “battery replacement” sometime in the near future but that he should get his cancer treatment underway. An appointment was made for a PM follow-up in 4 months. The author's interrogation of the PM showed that the device was indeed evaluated 126 days prior, and, at the time of that interrogation, the PM was 9 days past “elective replacement indicated.” Of note, this patient was in atrial fibrillation, he was not on anticoagulant therapy, he had no spontaneous ventricular depolarizations, and his PM was 45 days beyond the allowable (by US Food and Drug Administration standards) 90-day “normal functioning period” of a PM at elective replacement.⁎ His battery was 2.38 V with an impedance of 31,600 ohms, and the PM company suggested immediate replacement. He was admitted to the intensive care unit overnight, and his generator was replaced the next day.
Case 3
A 79-year-old woman presented for radiation to her pelvis for endometrial cancer. Because of her Alzheimer's disease, the anesthesia department was asked to provide sedation to prevent movement during her radiation exposure. Her ICD was therefore evaluated. The indication for implant was inducible ventricular tachycardia. According to notes from the chart, her ICD was implanted 68 months prior, and her last in-office comprehensive evaluation was more than 3 years prior. Interrogation of the ICD before the radiation therapy showed that the device would not provide any therapy (Fig 2). The discussion with the family resulted in no new generator placement.
Fig 2.
The initial screen from an ICD evaluation. The patient's last ICD check had been more than 3 years prior, and the ICD was more than 5 years old. This single-chamber ICD was nonfunctional for both pacing (VVI mode) and shock therapy.
Case 4
A 78-year-old woman was referred in preparation for mastectomy. She complained of palpitations. Her single-chamber PM had been implanted in the right pectoral position 5 months before the visit. It was a replacement generator implanted without lead revision for a generator at elective replacement at 12 years of implant. Her palpitations had been attributed to her generator battery depletion. Her previous in-office interrogation had taken place 4 months prior, and her previous telephone check was 2 months prior. Interrogation of her device revealed more than 2,400 high-rate ventricular events, some with heart rates as high as 320 beats/min. By conventional testing, the system behaved appropriately. However, when the patient raised her right arm over her head, the PM reported ectopy (Fig 3). The chest x-ray was within normal limits. At exploration, a defective ventricular lead was identified and a new lead was placed, eliminating the palpitations.
Fig 3.
A real-time telemetry strip from a St Jude single-chamber pacemaker with a marginal ventricular pacing lead. This tracing is the intracardiac electrogram from the ventricular lead while the patient moved her arm ipsilateral to the generator pocket over her head. The interpretation (called the marker channel) is displayed on the top line. The lower strip is the continuation of the upper strip. “V” means a pacemaker pace, and “R” indicates that the pacemaker sensed a ventricular depolarization. The pacemaker identifies an R-R interval as too short by showing an inverse “R.” The paper is standard 25 mm/sec, so the time period of 1 large box is 200 milliseconds. This intracardiac electrogram is significant for 3 serious issues: first, there is considerable noise causing ventricular oversensing, and second, there is failure to capture with the standard autocapture algorithm present in this pacemaker. Note that all but two “V” markers are followed quickly by a second “V,” indicating that the autocapture algorithm has detected a pacing noncapture and emitted a 4.5-V backup pulse. This issue was also found on the stored autocapture long-term threshold record (not shown). Third, the autocapture algorithm failed to detect two noncaptured events (asterisks).
Case 5
A 68-year-old woman was referred for PM evaluation before a left nephrectomy for renal cell cancer. She had a dual-chamber PM set to the VVI mode with a lower rate of 60 beats/min, and she explained that something was “wrong with the atrial lead from implant.” Her chest x-ray (Fig 4) showed that the atrial lead tip is superior to the junction of the superior vena cava and the right atrium. Pacing on this lead caused considerable right hemidiaphragmatic movement as well as chest pain. Her underlying rhythm was sinus at 70 beats/min, so there was no pacing. Her pacing rate was lowered to 50 beats/min to prevent unwanted pacing in the operating room because ventricular pacing at 60 beats/min would likely produce worse hemodynamics than sinus behavior with appropriate atrial transport at 51 beats/min.
Fig 4.
A chest x-ray depicting an improperly placed atrial lead is shown. Note that the distal tip of the atrial lead (ie, the pacing end) likely remains in the superior vena cave. Additionally, the right ventricular pacing lead lacks redundancy and might be under traction.
Case 6
An 85-year-old man was referred for PM evaluation before melanoma excision and rotational flap. His current PM was implanted in the left pectoral position, but he had a disfigured scar over the right side. His first PM had been implanted there 8 years prior. The generator was replaced for battery depletion 2 years prior, but it was explanted after it became infected. Apparently, the removal was accomplished by putting traction on the system, cutting the leads at the skin, and placing a bandage. As a result, the proximal, frayed lead ends migrated into the patient's distal vasculature (Figs 5A and B). PM interrogation revealed high atrial and high ventricular rates, but actual rhythm data were not present. As a result, no determination could be made as to whether the reported events were real or noise from lead-to-lead interference. Referral for lead extraction or lead fixation was declined.
Fig 5.
(A) A posterior-anterior chest x-ray of a patient with a dual-lead left-sided pacemaker and 2 abandoned right-sided pacemaker leads is shown. The proximal end of the original right-sided atrial pacing lead is frayed and is in the left subclavian vein near the subclavian-caval junction. The original proximal end of the right-sided ventricular pacing lead is frayed and can be seen in the pulmonary artery. A review of previous chest films (not shown) suggested that the proximal end of the right-sided atrial lead is continuing to migrate inward. (B) The companion lateral chest x-ray from the Figure 5A examination is shown. The leads are 1: left-sided (and active) atrial lead and 2: original right-sided atrial lead. The lead redundancy in the right atrium has increased over time when reviewing older films; 3: the left-sided (and active) ventricular pacing lead and 4: the original right-sided ventricular pacing lead whose proximal end has now migrated from the right subclavian vein and into the pulmonary artery.
Discussion
Unfortunately, these cases represent just “the tip of the iceberg” resulting from preanesthetic interrogation of PMs or ICDs in nearly 1,000 patients over the past 8 years at the author's cancer center. The author's center has identified many generators: at elective replacement (some of which had just been checked); with inadequate safety margins for pacing and sensing (some of which were life-threatening and required transfer from the clinic to the intensive care unit); atrial lead malpositions in the ventricle (eg, Fig 6); atrial and ventricular lead discontinuities (2 of which were iatrogenic from procedures involving the heart); and, of course, a woman whose ventricular lead had asymptomatically perforated the apex of the right ventricle (Fig 7). Whether the experience at this center is unique—after all, patients are told to get their cancer treated without regard to checking their PMs or ICDs—or whether it is representative of conditions in the medical community at large is unknown.
Fig 6.
A chest x-ray from a jaundiced 71-year-old man about to undergo endoscopic retrograde pancreaticocholangiogram with total intravenous anesthesia shows an atrial lead dislodgement into the ventricle. His dislodgement was confirmed during interrogation by pacing the lead designated “atrial” and obtaining wide complex QRS events in the form of a right bundle-branch block. The ventricular capture with this lead was not stable, suggesting that the lead was not truly fixed in the ventricle.
Fig 7.
A chest x-ray from an asymptomatic 70-year-old woman who was 4 years post surgery and chemotherapy for a gynecologic cancer. The chest film was part of her routine follow-up, and it shows perforation of the right ventricular apex by a recently placed right ventricular pacing lead. Her system had been placed a few weeks earlier for bradycardia.
Additionally, there is considerable literature evidence that “asymptomatic” issues persist. Maisel et al3 reviewed Food and Drug Administration records for PM and ICD failures (death or explantation because of malfunction other than battery depletion) for the period of 1990 to 2002. Even though the nature of this reporting scheme promotes underreporting of problems, for those 12 years, 2.25 million PMs were implanted with 8,834 (0.4%) confirmed (and reported) malfunctions and 30 deaths. For ICDs, 415,780 were implanted with 8,489 (2%) confirmed malfunctions and 31 deaths.3 Samain et al4 reported in abstract form that 13% of 73 PM patients required preoperative modification of PM programming to optimize cardiac pacing. Also in abstract form, Rozner et al5 reported a 2-year retrospective review of 172 PM patients presenting to a preoperative anesthesia clinic, showing 27/172 (16%) needed a preoperative intervention (9/27 were generator replacements for battery depletion).
Currently, a large number of PMs and ICDs are on “alert” for premature battery depletion (which would be a silent issue for a pacing-nondependent patient or a potentially deadly issue for an ICD patient)6, 7; magnet switch issues (approximately 46,000 ICDs manufactured by Guidant [Indianapolis, IN] have their magnet function permanently disabled by programming8); and lead issues that could result in failure to pace, failure to deliver appropriate antitachycardia therapy, or the provocation of an inappropriate shock,9 possibly resulting in the induction of a tachyarrhythmia or a myocardial injury.10
Keeping track of these alerts and recalls remains difficult, but patients with these devices might require specially tailored perioperative care. Identifying these patients can be difficult, especially in those who have not kept good contact with their implanting/following physician or who have not been evaluated for some time.
The American Society of Anesthesiologists Practice Advisory for the perioperative management of patients with cardiac rhythm management devices suggests that a timely preoperative evaluation of the pacing or antitachycardia system might reduce perioperative complications.11 In their most recent guidelines, the American College of Cardiology and the American Heart Association wrote that a comprehensive evaluation of the pacing system within 6 months of surgery might be acceptable,12 but using this guideline, some of the issues described in this article would have been missed.
Boriani et al's article serves as a reminder that an absence of symptoms or a normal electrocardiogram in a patient with a cardiac PM or ICD does not guarantee the presence of a working, optimized system that has been appropriately programmed for a perioperative experience (eg, the programmed heart rate is increased in a chronotropically incompetent patient to provide adequate oxygen delivery to tissues). Pacemaking and defibrillation systems can have considerable problems that remain “asymptomatic,” either because the patient's underlying heart rate or atrioventricular conduction time appears adequate at the preoperative visit, or, perhaps, the patient does not know what “normal” feels like. Another type of pacemaker complication is discussed in the Diagnostic Dilemma by Gandhi et al13 in this issue of the Journal.
Wherever clinicians treat patients and administer drugs with the ability to create significant perturbations in a patient's hemodynamics, it is expected that these implanted systems behave correctly and that they were appropriately installed, programmed, and tested. However, considerable data suggest otherwise, and the preoperative evaluation might be the very last opportunity to intervene and prevent a perioperative catastrophe.
References
- . Uneventful right ventricular perforation with displacement of a pacing lead into the left thorax. J Cardiothorac Vasc Anesth. 2008;22:423–425
- . Life-threatening ventricular dysrhythmias with inadvertent asynchronous temporary pacing after cardiac surgery. Anesthesiology. 1999;91:880–883
- Pacemaker and ICD generator malfunctions: analysis of Food and Drug Administration annual reports. JAMA. 2006;295:1901–1906
- Outcome in patients with a cardiac pacemaker undergoing noncardiac surgery. Anesthesiology. 2001;95:A142;(abstr)
- . Inadequate pacemaker follow-up detected at the preanesthetic visit. Anesthesiology. 2002;96:A1071;(abstr)
- . Urgent medical device safety information and corrective action (Vitality ICD) (Published 7/22/2006). http://www.bostonscientific.com/templatedata/imports/HTML/PPR/files/physician/vit_he_renewal.pdfAccessed January 1, 2007
- . Important patient management information (Sigma series pacemakers) (Published 11/2005). http://www.medtronic.com/crmLetter.htmlAccessed October 19, 2007
- Guidant: Urgent medical device safety information and corrective action (Contak Renewal [3,4,RF] ICD [magnet switch]). Published 6/23/2005. Available at: http://www.bostonscientific.com/templatedata/imports/HTML/PPR/ppr/support/current_advisories.pdf. Accessed April 11, 2008
- . Urgent medical device information: Sprint Fidelis lead patient management recommendations (Published 10/15/2007). http://www.medtronic.com/fidelis/physician-letter.htmlAccessed October 19, 2007
- Analysis of troponin I levels after spontaneous implantable cardioverter defibrillator shocks. J Cardiovasc Electrophysiol. 2002;13:144–150
- Practice advisory for the perioperative management of patients with cardiac rhythm management devices: Pacemakers and implantable cardioverter-defibrillators: A report by the American Society of Anesthesiologists Task Force on Perioperative Management of Patients with Cardiac Rhythm Management Devices. Anesthesiology. 2005;103:186–198
- ACC/AHA 2007 guidelines on perioperative cardiovascular evaluation and care for noncardiac surgery (A report of the American College of Cardiology/American Heart Association Task Force on practice guidelines (writing committee to revise the 2002 guidelines on perioperative cardiovascular evaluation for noncardiac surgery). Published 9/27/2007). http://circ.ahajournals.org/cgi/content/abstract/CIRCULATIONAHA.107.185699v1Accessed January 8, 2008
- Intracardiac masses associated with permanent endocardial pacemaker lead erosion through the skin. J Cardiothorac Vasc Anesth. 2008;22:492–494
- ⁎ According to US Food and Drug Administration guidelines, pacemakers and ICDs must provide pacing and defibrillation for at least 90 days after the onset of “elective replacement indicated,” which is internally detected by the generator. At the end of this 90-day period, the generator is allowed to fail completely. This 3-month window results in the guideline for at least a battery check of a pacemaker or ICD every 3 months. Battery checks can be accomplished in most cases with a telephone check of a pacemaker. Most ICD manufacturers now have telephonic monitoring of the ICD battery status and function.
PII: S1053-0770(08)00081-5
doi:10.1053/j.jvca.2008.02.022
© 2008 Elsevier Inc. All rights reserved.
Volume 22, Issue 3 , Pages 341-346, June 2008
