A pacemaker patient’s electrical dilemma
Mrs. A’s depression is worsening, and antidepressant trials have failed. Is electroconvulsive therapy a safe option for this patient with an implanted cardiac pacemaker?
What the evidence says
In evidence-based medicine, we tend to say: “In God we trust; all the others have to bring their data.” Unfortunately, it is difficult to conduct a trial of patients with multiple medical issues. Based on anecdotal reports, it appears that ECT use in patients with an implanted cardiac device such as a pacemaker or automatic internal cardioverter-defibrillator (AICD) generally is safe.8-12
One case report describes successful administration of ECT in a treatment-refractory depressed patient with an AICD. The AICD was deactivated during ECT and re-activated immediately upon completion of each treatment. The case report’s authors concluded that the presence of an AICD should not be a contraindication to ECT.13
A chart review of 3 patients with ICDs who received concurrent ECT found treatment was generally uneventful.12 One patient developed tachycardia with a rate-dependent left bundle branch block and hypotension in the recovery room, which responded promptly to esmolol. She did not experience similar events after subsequent ECT treatments.
Minimizing risk
In the absence of controlled data about the use of ECT in patients with implanted cardiac devices, crucial therapeutic decisions depend on the physician’s skill and judgment. Risk strategies can minimize complications (Algorithm).12 An internist or cardiologist experienced in pacemaker management should conduct a device interrogation—evaluating thresholds, lead impedance, and battery voltage and reviewing histograms, mode switch episodes, and stored electrograms—before the first ECT session and after the final one.
Most modern implantable pacemakers work in the synchronous (demand), rate-adaptive mode. In a patient in whom non-cardiac electrical signals cause bradycardia or asystole during ECT, the pacemaker can be reprogrammed to be less sensitive by placing a magnet over the pulse generator, which converts the pacemaker to an asynchronous (fixed), non-sensing mode. It is important to keep in mind that magnet application will not “turn off” a pacemaker; although each pacemaker is programmed to respond to a magnet in a specific fashion, the main response is asynchronous pacing.
Careful cardiac monitoring during ECT is essential (Table). The cardiologist or internist should be available during the first few ECT sessions to monitor for potential pacemaker interference or malfunction. This physician should be familiar with the pacemaker model and type of lead system so he or she can deactivate, reactivate, or reprogram the device.
Algorithm
Reducing risk when administering ECT to cardiac pacemaker patients
| Step 1 | |
| Evaluate the patient to ensure medical suitability for ECT and associated anesthesia | |
| Step 2 | ↓ |
| Conduct pacemaker interrogation (evaluating thresholds, lead impedance, and battery voltage and reviewing histograms, mode switch episodes, and stored electrograms) prior to first ECT treatment and after completion of full ECT course | |
| Step 3 | ↓ |
| Perform cardiac monitoring during and immediately after administering ECT | |
| Step 4 | ↓ |
| Have a magnet available to reprogram the pacemaker in the event of pacemaker inhibition or symptomatic bradycardia during ECT | |
| Step 5 | ↓ |
| Check that all monitoring devices are properly grounded, insulate the patient’s stretcher, and ensure that the patient does not touch anyone who is in contact with the ground during presentation of the ECT electrical stimulus | |
| ECT: electroconvulsive therapy | |
| Source: Reference 12 | |
Guidelines for monitoring cardiac pacemaker patients during ECT
| Use multilead ECG monitoring |
| Have equipment available to rapidly obtain central access (if vasoactive medications or transvenous pacing is needed) |
| Assess the plethysmography tracing of the pulse oximeter (a useful surrogate if the patient experiences dysrhythmias) |
| Have ready an external defibrillator |
TREATMENT: Successful ECT
We seek a medical consultation before initiating ECT. An internist performs device interrogation before the first ECT treatment and is present in the ECT treatment suite to ensure proper pacemaker conversion and to monitor for cardiac complications. The internist conducts another device interrogation after the acute series of ECT treatments.
Mrs. A tolerates the ECT sessions without cardiac complications. Her depressive symptoms respond well to 12 ECT sessions. She is more interactive and reports better attention and concentration. Although Mrs. A still has middle and initial insomnia, she denies thoughts of harming herself or anyone else.
Related resources
- Yarlagadda C. Pacemaker failure. www.emedicine.com/med/TOPIC1704.HTM.
- Atracurium • Tracrium
- Citalopram • Celexa
- Esmolol • Brevibloc
- Fluoxetine • Prozac
- Lorazepam • Ativan
- Methylphenidate • Ritalin, Concerta, others
- Nortriptyline • Aventyl, Pamelor, others
- Paroxetine • Paxil
- Sertraline • Zoloft
- Succinylcholine • Anectine
- Trazodone • Desyrel
- Venlafaxine • Effexor
- Ziprasidone • Geodon
Dr. Romanowicz reports no financial relationship with any company whose products are mentioned in this article or with manufacturers of competing products.
