Copyright©

Not for Sale

or Commer

cial Distribu

tion

Unauthoris

ed use pro

hibited. Aut

horised use

rs candown

load,

display, view

and print a

singlecopy

for persona

l use

40 Perspectives in Cardiology / August 2007

Stephen M. Chihrin, BSc; Paul A. Gould, MBBS, PhD, FRACP; andAndrew D. Krahn, MD, FRCPCPresented at Western University’s 6th Annual Western Arrhythmia SpecialtySymposium, London, Ontario, February 2007.

Temporary pacing generally involves short-term delivery of rate support in the context

of symptomatic bradycardia utilizing transcuta-neous pacing pads or a transvenous pacing leadattached to an external pacing generator. Thistypically provides a bridge until a permanentsolution to the bradycardia can take place, mostcommonly permanent pacemaker implantation,or alternatively, resolution of a reversible cause(bradycardia causing drugs, inferior MI). Choiceof temporary pacing method can vary consider-ably; important factors in this decision are:• the time available to initiate pacing,• the expertise of the operator and• the expected temporary pacing duration.

What are the indications fortemporary pacing?Temporary pacing should be considered as tem-porary treatment of an arrhythmia that producesacute hemodynamic instability which wouldbenefit from increased heart rate. In principle,the indications are similar to those for permanentpacing, which include:• acute management of bradyarrhythmiaproducing significant hemodynamicinstability, including (but not limited toasystole),

• Mobitz Type II atrioventricular (AV) block,• third degree AV block,

Temporary Pacing:It’s All About TimeTemporary pacing is a short-term treatment for arrhythmia that produces hemodynamicinstability and provides delivery of rate support. In this artice, Dr. Chihrin, Dr. Gould andDr. Krahn discuss the indications, delivery, complications and duration of temporary pacing.

Carl, 68, presents to your clinic describing oneweek of syncopal episodes occurring 5 to 10 timesper day, following a two day history of chestdiscomfort and nausea during which he did notseek medical care.

Carl’s physical exam is significant for a heart rateof 35 bpm. His jugular venous pressure is elevatedat 6 cm and demonstrates cannon A waves. AnECG reveals new Q waves in the inferior leads andbroad QRS complexes at a rate of 35 bpmdissociated from P waves occurring at a rate of60 bpm. You also note one interval of 4 secondswithout a QRS in which Carl feels lightheaded.

What treatment should Carl receive? Turn topage 42 to find out...

Carl’s chest pain

Should a patient receivingaggressive anticoagulation post-MI be transvenously paced?

The benefits of transvenous pacing mustbe weighed against the considerable riskfor hemorrhage if the patient has recentlyreceived thrombolytics or is on heparin. Ifthe patient is hemodynamically stable,transcutaneous pads could be placed asbackup instead.

FAQ

Temporary Pacing

• sinus pauses, or• profound bradycardia of any origin.Temporary pacing should also be considered toincrease heart rate in bradycardia-dependenttachycardia that is unresponsive to other therapiesand rarely, for overdrive suppression of tachy-cardias. The latter are uncommon clinically, butrepresent an indication where pacing may play adramatic role. In each case, it is important toweigh the possibility of life-threatening arrhyth-mias and the risk of complications encounteredduring temporary wire placement. For example,a patient with stable hemodynamics and a regu-lar narrow complex ventricular escape rhythm> 40 bpm, in the context of complete AV block,may be monitored closely with transcutaneouspacing pads in place, while a patient with signif-icant asystolic periods and unstable, broad com-plex escape, leading to syncope not responsiveto medical intervention, will derive benefit fromrelatively urgent temporary pacing.

How can temporary pacing bedelivered?Temporary pacing is provided via transvenous,transcutaneous, or epicardial means.Transcutaneous pacing can be performed asimmediate treatment for asystole but typicallyrequires substantial energy to capture the heart,causing considerable discomfort to mostpatients. Epicardial wires can be placed duringcardiac surgery to provide backup pacing in theevent of perioperative sinus or AV node injury.However, most commonly temporary pacing isprovided with a single lead transvenous pace-maker. Placement of a balloon-tipped lead canbe performed on a stretcher without fluoroscopysimilar to a Swan-Ganz catheter and is aidedconsiderably by vascular flow directing place-ment. Placement of a temporary pacing wirewith fluoroscopy is easier and safer secondary todirect visualization of the lead, making it

Perspectives in Cardiology / August 2007 41

Does temporary pacing lead topacemaker dependence?

It is possible, as pacing has been shown topromote pacemaker dependence in somepatients, making proper lead placementand appropriate monitoring critical.

FAQ

Dr. Chihrin is a Third Year MedicalStudent, University of WesternOntario, London, Ontario.

About the authors...

How should temporary pacingbe initiated in a patient with apermanent pacemaker or leadfailure?

A temporary wire can still be placed. Thecase for a right internal jugular approachis at its strongest in this scenario, as toensure that a subclavian approach isprotected for permanent device placementat the time of repair should the initialdevice, most commonly placed via theleft subclavian vein, be compromised.

FAQ

Dr. Gould is a Cardiologist, SeniorElectrophysiological and PacingFellow at London Health SciencesCenter. He has also completed aPhD in Arrhythmias and HeartFailure, London, Ontario.

Dr. Krahn is a Professor and Directorof Education, Division of Cardiology,Department of Medicine and is theProgram Director, ElectrophysiologyTraining Program, Western University,London, Ontario.

42 Perspectives in Cardiology / August 2007

Temporary Pacing

preferable if time permits. Without imaging, ahard-tipped lead can be advanced “blindly”—that is, advanced with the pacing generator acti-vated; observation of ventricular capture and leftbundle branch pattern following each pacingspike will confirm placement in the right ventri-cle (RV). A more careful, but time consuming,approach utilizes the pacing wire as an ECG leadfor observation of changes in ECG pattern dur-ing advancement. While any site within the RVwill provide adequate temporary pacing, RV api-cal placement affords the greatest stability.Newer temporary pacing wires contain actively-fixating helices, which can be affixed to theendocardium to help maintain positioning, butrequire more operator expertise.Access sites for transvenous pacing include:

• the internal jugular,• subclavian,• femoral and rarely,• the brachial veins.The right internal jugular is favourable as it isassociated with decreased complications andspares subclavian access for future permanentpacemaker placement. The femoral vein is

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

Recognizing symptomatic third degreeatrioventricular block in the context of a recent MI,you arrange for transfer to the hospital where Carlwill receive temporary pacing until the AV blockresolves or a permanent pacemaker is implanted.

Carl’s case cont’d...

What level of monitoring isrequired during temporarypacing?

Traditional temporary pacing, usingstandard temporary wires, has beenshown to lose capture more frequentlywhen compared to the exceedingly lowrisk with permanent pacemakers.Telemetry should be maintained for theduration of temporary pacing. Dailyportable chest x-rays can be helpful toassess lead position and anticipateincipient dislodgement.

FAQ

generally undesirable secondary to increasedincidence of deep vein thrombosis and infection.

What complications arecommon?Complications of temporary pacing have beenreported to be as high as 35% in a study ofBritish community hospitals,1 but typicallyoccur in 2% to 10% of patients. Complicationsinclude:• local injury at the venous access site,• pneumothorax during subclavian approach,• hemorrhage,• cardiac perforation and pericardialtamponade,

• arrhythmia induction including ventriculartachycardia and ventricular fibrillation,

• post-procedural lead displacement resultingin loss of pacing and

• infection.Complication frequency has been inverselyassociated with physician expertise. As such, aminimum of 10 temporary wires should be per-formed under guidance for physicians acquiringthis skill.2

How long can a patient be pacedwith a temporary wire?Most studies have shown a relatively low rate ofinfection within one week of traditional transve-nous temporary pacing. Infection can be reducedby avoiding femoral access and maintaininghigh standards of IV access care.Recently, temporary permanent pacing has

been offered at some centers, utilizing active-fixation leads and externally placed, reusablepermanent pacemakers, affixed to the skin witha sterile occlusive dressing (Figure 1). If perma-nent pacing is required, the system is removed,the device sterilized for future external use, the

lead is discarded and a new permanent pacingsystem is implanted at a separate site. Utilized inscenarios where extended temporary pacing isexpected but permanent pacing is not, thisapproach improves the reliability of temporarypacing, decreases monitoring cost and providesfor increased patient comfort and mobility.3

References1. Murphy JJ: Current Practice and Complications of Temporary

Transvenous Cardiac Pacing. BMJ 1996; 312(7039):1134.2. ACP/ACC/AHA Task Force on Clinical Privileges in Cardiology: Clinical

Competence in Insertion of a Temporary Transvenous VentricularPacemaker. J Am Coll Cardiol 1994; 23(5):1254-7.

3. Chihrin SM, Mohammed U, Yee R, et al: Utility and Cost Effectivenessof Temporary Pacing Using Active Fixation Leads and an ExternallyPlaced Reusable Permanent Pacemaker. Am J Cardiol 2006;98(12):1613-5.

Temporary Pacing

Perspectives in Cardiology / August 2007 43

• Temporary pacing should be provided whenbradycardia is hemodynamically significantand refractory to other interventions

• The right internal jugular approach is associatedwith lower complications and protectssubclavian access for future permanent deviceplacement

• Balloon-guided pacing wires are useful insituations where fluoroscopy is unavailable orintroduces too much delay. However, theirefficacy is compromised in states of low bloodflow

• Temporary pacing requires close monitoringincluding telemetry to avoid dislodgement.The duration of temporary pacing using atransvenous approach should be minimized,since complications increase with time

Take-home message

PCard