Overdrive Pacing
OVERVIEW
- Overdrive pacing = pacing the heart at a higher rate than the native heart rate
- VT or VF can result -> always have DC cardioversion available
INDICATIONS
- failure of drug therapy
- recurrent arrhythmia
- contraindication to cardioversion (digoxin toxicity)
- aid to differentiate VT from SVT
RHYTHMS THAT CAN BE CONTROLLED
- AV junctional tachycardia
- paroxysmal re-entrant SVT
- atrial flutter (rate 320-340)
- SVT with rapid ventricular response that fails to revert
- VT (may precipitate VF)
RHYTHMS THAT CAN’T BE CONTROLLED
- AF
- VF
- sinus tachycardia
OVERDRIVE PACING VS CARDIOVERSION
- may assist with rhythm diagnosis
- can use in digoxin toxicity
- doesn’t require GA
- avoids complications of DC shock (myocardial depression)
- pacing available post electrical version (in case of bradycardia or asystole)
OVERDRIVE PACING VS DRUGS
- may aid in rhythm diagnosis
- avoid drug induced cardiac depression and other side effects
- can be used when drug therapy fails
- termination of the tachycardia with pacing often immediate
- standby pacing immediately available
Critical Care
Compendium
Chris is an Intensivist and ECMO specialist at The Alfred ICU, where he is Deputy Director (Education). He is a Clinical Adjunct Associate Professor at Monash University, the Lead for the Clinician Educator Incubator programme, and a CICM First Part Examiner.
He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives. He was one of the founders of the FOAM movement (Free Open-Access Medical education) has been recognised for his contributions to education with awards from ANZICS, ANZAHPE, and ACEM.
His one great achievement is being the father of three amazing children.
On Bluesky, he is @precordialthump.bsky.social and on the site that Elon has screwed up, he is @precordialthump.
| INTENSIVE | RAGE | Resuscitology | SMACC
Hi! This might be playing with semantics, but I did not think that AV junctional tachycardia would usually be categorized as a rhythm that can be “overdrive paced”? As a supportive measure, we will indeed atrially pace children with post-operatve JET at a faster rate than the junctional rhythm until it self-resolves (to regain AV synchrony and ensure better cardiac output). I had previously understood that “overdrive pacing” is usually a term reserved for pacing at a faster rate with the goal of “breaking” the arrhythmia by disrupting the re-entrant circuit or over-riding the ectopic pacemaker, and it is performed over a few seconds. Let me know if I’ve misunderstood it – I was involved in teaching pacing to australian exam-takers and I wanted to clarify the term. Thank you very much.
Why can’t atrial fibrillation be overdrive paced?
Hi M,
I believe (and I’ve just consulted with a cardiologist as well as some of the literature) that it’s because it just isn’t effective. There were some early noughties (early ’00s to early ’10s) trials that looked at long-term prevention in pAF (and treatment) and overdrive atrial pacing and there wasn’t a benefit (unless you were a pacemaker company, because the batteries required replacing more frequently). Best evidence is with atrial flutter, SVT (can convert to AF sometimes) and VT (with ventricular overdrive pacing — although a high risk of converting to VF, and VF can’t be overdrive paced!).
There was some earlier evidence that bi- and/or multi-site atrial pacing may be more effective at overdrive atrial pacing, however this hasn’t really come to fruition, nor is it currently practised (to my knowledge) — the atria are fibrillating and are difficult to re-synchronise!
Hope this helps,
James