- Common indications for placement of an implantable cardioverter-defibrillator (ICD) include VT/VF resulting in cardiac arrest, sustained VT in patient with structural heart disease, and end-stage cardiomyopathies with low ejection fraction, long QT syndrome, and Brugada syndrome.
- Most common presentation is patient presenting to ED after an ICD shock.
- More than 30% of patients with history of VT/VF receive an appropriate shock within two years of ICD implantation.
- Common triggers include electrolyte imbalance, ischemia, heart failure, medication noncompliance, and recent change to antiarrhythmic medications.
- Causes of inappropriate shocks include:
- Dysrhythmias (most common) including AF, SVT, or sinus tachycardia.
- Lead fracture, lead displacement or battery depletion.
- T wave oversensing, QRS complex double-counting.
- Interference from external electromagnetic radiation (metal detectors, MRI)
- Causes of failure of ICD to deliver successful shock include:
- Lead fracture, lead displacement, scar tissue or battery depletion.
- Recent change to antiarrhythmic medications.
- Electrolyte imbalance.
- Other complications associated with ICD implantation include wound hematoma, site/lead infection, pericardial effusion, PTX, and upper extremity DVT/SVT syndrome.
- Early diagnosis and treatment of ICD shocks will reduce psychological distress and improve quality of life in patients with ICDs.
- Initial investigations in all patients presenting with single/multiple ICD shocks include cardiac monitoring, 12-lead ECG, basic labwork including extended electrolytes (particularly, K and Mg), TSH, and CXR to diagnose lead displacement/fracture.
- If suspect ischemia, consider cardiac biomarkers +/- bedside echocardiography.
- All patients presenting with multiple shocks will require early cardiology consult OR electrophysiology consult for device interrogation if directly available.
- If inappropriate shocks due to dysrhythmia or suspected device malfunction, place magnet over ICD to disable defibrillator. Treat SVT accordingly with beta blockers/CCB.
- If appropriate shocks are unsuccessful in correcting arrhythmia AND hemodynamically unstable, place defibrillator pads in anterior-posterior configuration at least 10cm from ICD, resuscitate according to ACLS protocols, and treat underlying cause.
- If shockable rhythm not adequately treated by ICD, place magnet over device to deactivate if necessary.
- If shockable rhythm treated by ICD but patient is in recurrent VT (storm), do not place magnet. These patients require acute management of underlying dysrhythmia.
- These patients will require early consultation with cardiology and high-priority transfer to facility with cardiac/critical care unit.
- Well-appearing, asymptomatic patient after single shock can be discharged home after arranging for follow-up with cardiologist and pacemaker clinic.
Endocarditis / Device Infections
- Pocket infection should be suspected in patient presenting with local inflammation, while lead infection may present with bacteremia +/- endocarditis.
- Perform TTE, CXR and blood culturesx2 prior to empiric ABX in all patients with suspected ICD-related infection.
- Start vancomycin 25mg/kg IV x1 loading dose, then 15mg/kg IV q8-12h.
- Consult physician who inserted device for surgical removal.
- Aspiration +/- culture of device pocket should be performed by experienced physician.
Pericardial Effusion (Tamponade, Migration Lead)
- Perform CXR and bedside echocardiography to confirm cardiac tamponade in patient with newly inserted cardiac device who presents with hypotension.
- For large pocket hematoma, consider consult for surgical evacuation. Do not perform needle aspiration.
Quality Of Evidence?
We are highly confident that the true effect lies close to that of the estimate of the effect. There is a wide range of studies included in the analyses with no major limitations, there is little variation between studies, and the summary estimate has a narrow confidence interval.
We consider that the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. There are only a few studies and some have limitations but not major flaws, there are some variations between studies, or the confidence interval of the summary estimate is wide.
When the true effect may be substantially different from the estimate of the effect. The studies have major flaws, there is important variations between studies, of the confidence interval of the summary estimate is very wide.
- Role of early device removal in cardiac device infection: Strong association with lower short and long-term mortality.
- Duration of antimicrobial therapy following device extraction: Based largely on retrospective studies analyzing outcomes associated with common clinical practice.
Viganego F, O’Donoghue S, Eldadah Z, et al. Effect of early diagnosis and treatment with percutaneous lead extraction on survival in patients with cardiac device infections. Am J Cardiol 2012;109:1466-1471.
The purpose of this document is to provide health care professionals with key facts and recommendations for the diagnosis and treatment of patients in the emergency department. This summary was produced by the BC Emergency Medicine Network and uses the best available knowledge at the time of publication. However, healthcare professionals should continue to use their own judgment and take into consideration context, resources and other relevant factors. The BC Emergency Medicine Network is not liable for any damages, claims, liabilities, costs or obligations arising from the use of this document including loss or damages arising from any claims made by a third party. The BC Emergency Medicine Network also assumes no responsibility or liability for changes made to this document without its consent.
Last Updated Feb 17, 2022
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