Wearable Cardioverter Defibrillator (WCD)

WCD may be considered medically necessary when the clinical criteria in this Policy are met and serves as a bridge to an implantable cardioverter defibrillator or other more invasive intervention and is at high risk for sudden cardiac death.

Description:

Automatic defibrillators are devices that are capable of monitoring cardiac rhythms, detecting dysrhythmias, and delivering a defibrillation shock to the heart when appropriate without any user decision-making. There are two FDA approved DME Wearable Cardioverter Defibrillator (WCD) under the brand names LifeVest™ and Assure™. The WCD's monitor electrocardiogram (ECG) changes through a programmable microprocessor-based device and an electrode belt containing non- adhesive electrodes that are integrated into the vest.

The WCD is a combination of two different devices. As a defibrillator, if a life-threatening arrhythmia (ventricular fibrillation) is detected, the non-adhesive therapeutic electrodes release a conductive gel to the skin and deliver a high-energy shock to the heart to return the heart to normal sinus rhythm. As a cardioverter, the WCD delivers a low-energy shock when ventricular tachycardia is detected. The WCD is designed to perform the same functions as an automatic implantable cardioverter defibrillator (ICD). It is worn outside the body and noninvasive. Alarms sound prior to the delivery of a shock, and if the patient is conscious, the device may be disarmed.

Clinical Criteria: (Indications/Limitations)

1. Automatic external defibrillators may be considered medically necessary if ONE of the following criteria is met:
   • A previously implanted defibrillator now requires explantation
   • A documented episode of ventricular fibrillation or a sustained, lasting 30 seconds or longer, ventricular tachyarrhythmia. The dysrhythmias may be spontaneous or induced during an electrophysiological (EP) study, but may not be due to a transient or reversible cause and must not have occurred during the first 48 hours of an acute myocardial infarction
   • Left ventricular ejection fraction less than or equal to 0.35 which is documented from a prior myocardial infarction or dilated cardiomyopathy
   • Inherited or familial conditions with a high risk of life-threatening ventricular tachyarrhythmia (i.e. long QT syndrome or hypertrophic cardiomyopathy)
   • Awaiting Implantable Cardiac Defibrillator or heart transplant
2. Utilization Guidelines:
   • Prior authorization is required with monthly documentation for continued coverage.
   • Authorization is provided monthly after initial authorization of 60 days.
   • Required documentation includes medical records indicating member usage of the automatic external defibrillator.
   • Documentation showing that member is being reassessed monthly for implantable cardioverter-defibrillator candidacy.

NOTE: Patients may not comply with wearing the WCD for a variety of reasons, including device size and weight, skin rash, itching, and problems sleeping. Efficacy of the WCD in the prevention of sudden cardiac death is highly dependent on patient compliance and appropriate use of the device.

Limitations:

In spite of its overall efficacy for terminating life-threatening ventricular arrhythmias, the WCD does have some limitations.

• The device must be fitted to each patient, and some patients may not have a good fit due to body habitus. Its external nature does not allow for pacemaker functionality and introduces a component of patient interaction and compliance as well as the potential for external noise leading to inappropriate shocks. The device must be removed for bathing, but no protection is afforded while the device is off. Therefore, it is advisable that caregivers or other persons be nearby during these periods when the WCD is not worn. Comfort may also be an issue for some patients due to the size and weight of the device.
• Patient size. The WCD can only be fitted on patients with a chest circumference less than 57 inches (144 cm); therefore, it may not be an option for morbidly obese patients.
• Lack of pacemaker functionality. Because of its external nature, the WCD is not able to function as a pacemaker.
  • The WCD cannot deliver pacing therapies to treat bradycardia or asystole.
  • The WCD cannot provide antitachycardia pacing for VT, which can reduce patient shocks, when effective.