This document addresses the use of implantable transvenous and subcutaneous cardioverter-defibrillator devices to monitor the heart rhythm and deliver an electrical shock when a life-threatening ventricular arrhythmia is detected.

For information regarding other technologies for cardiac disease, see:

• MED.00055 Wearable Cardioverter Defibrillators
• CG-SURG-63 Cardiac Resynchronization Therapy with or without an Implantable Cardioverter Defibrillator for the Treatment of Heart Failure

Clinical Indications

Medically Necessary:

Implantable transvenous cardioverter-defibrillator (ICD) therapy is considered medically necessary when the criteria below have been met (I , II, and III):

1. Indications:
   1. Treatment of ventricular tachyarrhythmias; or
   2. Prevention of sudden cardiac death (SCD);
      and
2. Prior Treatment and Prognosis Criteria:
   1. Individual is
      1. On optimal medical therapy; and
      2. Has a reasonable expectation of survival with a good functional status for more than 1 year:
         and
3. Clinical criteria (one of the following is present [A through K]):
   1. After evaluation to define the cause of the event and to exclude any completely reversible causes in survivors of cardiac arrest due to either ventricular fibrillation (VF) or hemodynamically unstable sustained ventricular tachycardia (VT); or
   2. Those with structural heart disease and spontaneous sustained VT, whether hemodynamically stable or unstable; or
   3. Those with syncope of undetermined origin with clinically relevant, hemodynamically significant sustained VT; or
   4. Those with nonischemic dilated cardiomyopathy (NIDCM) who have an LVEF (left ventricular ejection fraction) less than or equal to 35% after 3 months of Guideline-directed medical therapy (GDMT) and who are in New York Heart Association (NYHA) functional Class II or III Heart Failure (HF); or
   5. Those with ischemic cardiomyopathy due to a prior myocardial infarction (MI) who are at least 40 days or more post-MI, with LVEF less than or equal to 30% and are in NYHA functional Class I HF after 3 months of GDMT or with an LVEF less than or equal to 35% and in NYHA Class II or III HF after 3 months of GDMT; or
   6. Those with nonsustained VT due to prior MI, LVEF less than 40%, and inducible VF or sustained VT at electrophysiological study; or
   7. Those with long-QT syndrome who are experiencing either syncope or VT while receiving beta blockers; or
   8. Those with confirmed hypertrophic cardiomyopathy (HCM) with 1 or more of the following major risk factors for sudden cardiac death (SCD):
      1. Personal history of cardiac arrest or sustained ventricular arrhythmias; or
      2. Personal history of syncope suspected by clinical history to be arrhythmic within the previous 12 months; or
      3. Family history of HCM-related sudden death in one or more 1st or 2nd degree relatives who are less than or equal to 50 years of age or in two or more 3rd degree relatives who are less than or equal to 50 years of age; or
      4. LV apical aneurysm, independent of size; or
      5. LV systolic dysfunction (LVEF less than 50%); or
      6. Nonsustained VT episodes on ECG or continuous ambulatory electrocardiographic monitoring; or
      7. Left ventricular (LV) wall thickness greater than or equal to 30 mm in any LV segment; or
   9. For individuals with symptomatic sustained VT in association with congenital heart disease who have undergone hemodynamic and electrophysiological evaluation; (catheter ablation or surgical repair may offer possible alternatives in carefully selected individuals); or
   10. For individuals with congenital heart disease with recurrent syncope of undetermined origin in the presence of either ventricular dysfunction or inducible ventricular arrhythmias at electrophysiological study; or
   11. For individuals with cardiac sarcoidosis when one (1) or more of the following are met:
       1. Sustained VT or survivors of sudden cardiac arrest or with an LVEF of 35% or less; or
       2. LVEF of greater than 35% with syncope or evidence of myocardial scar by cardiac MRI or PET scan; or
       3. LVEF of greater than 35% with inducible sustained ventricular arrhythmias.

Implantable transvenous cardioverter-defibrillator (ICD) therapy is considered medically necessary for individuals with a confirmed Brugada syndrome diagnosis when either of the following criteria is met (A or B):

1. History of unexplained syncope, documented spontaneous sustained VT with or without syncope, or survivor of a cardiac arrest; or
2. Family history of a first- or second-degree relative with sudden cardiac death due to Brugada syndrome or that is unexplained.

Subcutaneous cardioverter-defibrillator (S-ICD) devices are considered medically necessary for the following at-risk individuals when the medically necessary criteria above for implantable transvenous cardioverter-defibrillator (ICD) therapy have been met and the individual does not require cardiac pacing:

1. Individuals with a lack of venous access; or
2. Individuals who are immunocompromised; or
3. Individuals with prosthetic valves; or
4. Individuals with recurrent transvenous lead-related, device-pocket or systemic infections; or
5. Individuals with endocarditis; or
6. Pediatric individuals.*

*The FDA interprets pediatrics as individuals who are 21 years of age or younger (that is, up to, but not including, the 22nd birthday). See the Discussion/General Information section for additional information about use of ICD therapy in children.

Note: For use of combined ICD/Biventricular pacing (CRT-ICD) devices, in cases of NYHA Class IV heart failure and for other indications, see CG-SURG-63 Cardiac Resynchronization Therapy (CRT), with or without an Implantable Cardioverter Defibrillator (CRT/ICD) for the Treatment of Heart Failure.

Not Medically Necessary:

The use of an implantable transvenous cardioverter-defibrillator is considered not medically necessary when the criteria above are not met and for any other indications.

The use of a subcutaneous ICD (S-ICD) is considered not medically necessary for all indications when the above criteria are not met.