Temporary Pacing: It’s All About Time

Temporary pacing is a short-term treatment for that produces hemodynamic instability and provides delivery of rate support. In this artice, Dr. Chihrin, Dr. Gould and Dr. Krahn discuss the indications, delivery, complications and duration of temporary pacing.

Stephen M. Chihrin, BSc; Paul A. Gould, MBBS, PhD, FRACP; and Andrew D. Krahn, MD, FRCPC Presented at Western University’s 6th Annual Western Arrhythmia Specialty Symposium, London, Ontario, February 2007.

emporary pacing generally involves short- Tterm delivery of rate support in the context Carl’s of symptomatic utilizing transcuta - Carl, 68, presents to your clinic describing one neous pacing pads or a transvenous pacing lead week of syncopal episodes occurring 5 to 10 times attached to an external pacing generator. This per day, following a two day history of chest typically provides a bridge until a permanent discomfort and nausea during which he did not solution to the bradycardia can take place, most seek medical care. commonly permanent pacemaker implantation, Carl’s physical exam is significant for a heart rate or alternatively, resolution of a reversible cause of 35 bpm. His is elevated (bradycardia causing drugs, inferior MI). Choice at 6 cm and ©demonstrates cannon A wavest. Ain on of temporary pacing method can vary consider - ECG rehveatls new Q waves in the inifebrioruleads and ibrgoad QRS complexes at asratte orf 35 bpdm , ably; important factors in this decision are: yr Di nloa op dissociated froimaP wlaves occdurorinwg at a rate of 60 bpm. Yocu also note ocnaeninterval of 4 seconds • the time available to initiate paCcing, er sers l use mwithout a QeRdSuin which Csarol fneeals lightheaded. • the expertise of the operator and om horis r per C . Aut py fo • the expected temporary pacingoduration. ited e co le rohib sWinhgalt treatment should Carl receive? Turn to Sa se p nt a page 42 to find out... r ed u d pri t fo horis an Whaot are thnaeuitndicat,ivoinews for N U splay temporary pacdiing? FAQ Temporary pacing should be considered as tem - porary treatment of an arrhythmia that produces Should a patient receiving acute hemodynamic instability which would aggressive anticoagulation post- benefit from increased heart rate. In principle, MI be transvenously paced? the indications are similar to those for permanent pacing, which include: The benefits of transvenous pacing must • acute management of bradyarrhythmia be weighed against the considerable risk producing significant hemodynamic for hemorrhage if the patient has recently instability, including (but not limited to received thrombolytics or is on heparin. If the patient is hemodynamically stable, asystole), transcutaneous pads could be placed as • Mobitz Type II atrioventricular (AV) block, backup instead. • third degree AV block,

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• sinus pauses, or • profound bradycardia of any origin. FAQ Temporary pacing should also be considered to How should temporary pacing increase heart rate in bradycardia-dependent be initiated in a patient with a that is unresponsive to other therapies permanent pacemaker or lead and rarely, for overdrive suppression of tachy - cardias. The latter are uncommon clinically, but failure? represent an indication where pacing may play a A temporary wire can still be placed. The dramatic role. In each case, it is important to case for a right internal jugular approach weigh the possibility of life-threatening arrhyth - is at its strongest in this scenario, as to mias and the risk of complications encountered ensure that a subclavian approach is during temporary wire placement. For example, protected for permanent device placement a patient with stable hemodynamics and a regu - at the time of repair should the initial lar narrow complex ventricular escape rhythm device, most commonly placed via the left subclavian , be compromised. > 40 bpm, in the context of complete AV block, may be monitored closely with transcutaneous pacing pads in place, while a patient with signif - icant asystolic periods and unstable, broad com - FAQ plex escape, leading to syncope not responsive Does temporary pacing lead to to medical intervention, will derive benefit from pacemaker dependence? relatively urgent temporary pacing. It is possible, as pacing has been shown to How can temporary pacing be promote pacemaker dependence in some patients, making proper lead placement delivered? and appropriate monitoring critical. Temporary pacing is provided via transvenous, transcutaneous, or epicardial means. Transcutaneous pacing can be performed as About the authors... immediate treatment for asystole but typically Dr. Chihrin is a Third Year Medical requires substantial energy to capture the heart, Student, University of Western Ontario, London, Ontario. causing considerable discomfort to most patients. Epicardial wires can be placed during cardiac surgery to provide backup pacing in the Dr. Gould is a Cardiologist, Senior event of perioperative sinus or AV node injury. Electrophysiological and Pacing However, most commonly temporary pacing is Fellow at London Health Sciences provided with a single lead transvenous pace - Center. He has also completed a PhD in and Heart maker. Placement of a balloon-tipped lead can Failure, London, Ontario. be performed on a stretcher without fluoroscopy similar to a Swan-Ganz catheter and is aided Dr. Krahn is a Professor and Director of Education, Division of Cardiology, considerably by vascular flow directing place - Department of Medicine and is the ment. Placement of a temporary pacing wire Program Director, Electrophysiology with fluoroscopy is easier and safer secondary to Training Program, Western University, London, Ontario. direct visualization of the lead, making it

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preferable if time permits. Without imaging, a Carl’s case cont’d... hard-tipped lead can be advanced “blindly”— that is, advanced with the pacing generator acti - Recognizing symptomatic third degree vated; observation of ventricular capture and left atrioventricular block in the context of a recent MI, you arrange for transfer to the hospital where Carl bundle branch pattern following each pacing will receive temporary pacing until the AV block spike will confirm placement in the right ventri - resolves or a permanent pacemaker is implanted. cle (RV). A more careful, but time consuming, approach utilizes the pacing wire as an ECG lead for observation of changes in ECG pattern dur - ing advancement. While any site within the RV FAQ will provide adequate temporary pacing, RV api - What level of monitoring is cal placement affords the greatest stability. required during temporary Newer temporary pacing wires contain actively- pacing? fixating helices, which can be affixed to the to help maintain positioning, but Traditional temporary pacing, using require more operator expertise. standard temporary wires, has been Access sites for transvenous pacing include: shown to lose capture more frequently • the internal jugular, when compared to the exceedingly low • subclavian, risk with permanent pacemakers. • femoral and rarely, Telemetry should be maintained for the • the brachial . duration of temporary pacing. Daily portable chest x-rays can be helpful to The right internal jugular is favourable as it is assess lead position and anticipate associated with decreased complications and incipient dislodgement. spares subclavian access for future permanent pacemaker placement. The femoral vein is

Figure 1. Temporary pacing using an externally placed, reusable permanent pacemaker and disposable active-fixation lead.

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generally undesirable secondary to increased incidence of deep vein thrombosis and infection. Take-home message

• Temporary pacing should be provided when What complications are bradycardia is hemodynamically significant common? and refractory to other interventions Complications of temporary pacing have been • The right internal jugular approach is associated reported to be as high as 35% in a study of with lower complications and protects British community hospitals, 1 but typically subclavian access for future permanent device occur in 2% to 10% of patients. Complications placement include: • Balloon-guided pacing wires are useful in • local injury at the venous access site, situations where fluoroscopy is unavailable or • pneumothorax during subclavian approach, introduces too much delay. However, their • hemorrhage, efficacy is compromised in states of low • cardiac perforation and pericardial flow tamponade, • Temporary pacing requires close monitoring • arrhythmia induction including ventricular including telemetry to avoid dislodgement. tachycardia and ventricular fibrillation, The duration of temporary pacing using a • post-procedural lead displacement resulting transvenous approach should be minimized, in loss of pacing and since complications increase with time • infection. Complication frequency has been inversely associated with physician expertise. As such, a lead is discarded and a new permanent pacing minimum of 10 temporary wires should be per - system is implanted at a separate site. Utilized in formed under guidance for physicians acquiring scenarios where extended temporary pacing is this skill. 2 expected but permanent pacing is not, this approach improves the reliability of temporary How long can a patient be paced pacing, decreases monitoring cost and provides 3 PCard with a temporary wire? for increased patient comfort and mobility. Most studies have shown a relatively low rate of infection within one week of traditional transve - References nous temporary pacing. Infection can be reduced 1. Murphy JJ: Current Practice and Complications of Temporary by avoiding femoral access and maintaining Transvenous Cardiac Pacing. BMJ 1996; 312(7039):1134. 2. ACP/ACC/AHA Task Force on Clinical Privileges in Cardiology: Clinical high standards of IV access care. Competence in Insertion of a Temporary Transvenous Ventricular Recently, temporary permanent pacing has Pacemaker. J Am Coll Cardiol 1994; 23(5):1254-7. 3. Chihrin SM, Mohammed U, Yee R, et al: Utility and Cost Effectiveness been offered at some centers, utilizing active- of Temporary Pacing Using Active Fixation Leads and an Externally fixation leads and externally placed, reusable Placed Reusable Permanent Pacemaker. Am J Cardiol 2006; 98(12):1613-5. permanent pacemakers, affixed to the skin with a sterile occlusive dressing (Figure 1). If perma - nent pacing is required, the system is removed, the device sterilized for future external use, the

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