- implantable device defibrillator +/- pacemaker (counter shock vector is from RV -> both SVC)
- VF or sudden cardiac death survivors
- VT-associated syncope not caused by MI or other correctable cause
- minimally symptomatic VT with EF <35%
- previous MI, LVEF ‘monitor only’ mode
- dysrhythmia resistant to anti-arhythmics or if anti-arrhythmics contra-indicated
- ideally have the cardiac technician present to enable the defibrillation function
- have defibrillator close to hand (attach prior to surgery)
- place pads at cardiac apex and below right clavicle
- nurse in HDU/ ICU with resuscitation equipment close by
- cardiac technician interrogation and reprogramming post surgery
- check medications as they may change threshold
- monitor for infection
- look for lead displacement or fracture
- check with cardiologist/technician for programming and idiosyncracies of unit
- monitor ECG
- have an external defibrillator available
MAGNETS AND AICDs
- no longer recommended to place magnet over AICDs — only applicable to older non-reprogrammable pacemakers
- magnet placement turns off antiarrhythmic program but has no affect on backup pacemaker
- all modern AICDs are reprogrammable
PROBLEMS WITH ICDs
- battery depletion
- lead fracture or displacement (by surgery, defibrillation or CVL/PAC placement)
- lead or box infection (e.g. due to bacteremia)
- multiple shocks due to algorithm error, sensing failure, oversensing of physiological signals and lead failure
- EMF interference from shaver, TV remote, MRI and also possible
- ICD may be switched off intra-operatively because of interference from diathermy (need to turn back on!)
- threshold may be changed by medications
References and Links
- Aguilera AL, Volokhina YV, Fisher KL. Radiography of cardiac conduction devices: a comprehensive review. Radiographics. 2011 Oct;31(6):1669-82. doi: 10.1148/rg.316115529. PubMed PMID: 21997988.
- Atlee JL, Bernstein AD. Cardiac rhythm management devices (part I): indications, device selection, and function. Anesthesiology. 2001 Nov;95(5):1265-80. PMID: 11684999.
- Atlee JL, Bernstein AD. Cardiac rhythm management devices (part II): perioperative management. Anesthesiology. 2001 Dec;95(6):1492-506. PMID: 11748411.
FOAM and web resources
- Course: ICD Essentials
- What is an Implantable Cardioverter Defibrillator (ICD)?
- Who qualifies for an ICD?
- What is ATP (anti-tachycardia pacing)?
- Defibrillation for VF and VT when ATP fails