Medical Policy: 02.02.16 

Original Effective Date: July 2013 

Reviewed: August 2017 

Revised: June 2018 


Benefit Application:

Benefit determinations are based on the applicable contract language in effect at the time the services were rendered. Exclusions, limitations or exceptions may apply. Benefits may vary based on contract, and individual member benefits must be verified. Wellmark determines medical necessity only if the benefit exists and no contract exclusions are applicable. This medical policy may not apply to FEP. Benefits are determined by the Federal Employee Program.


This Medical Policy document describes the status of medical technology at the time the document was developed. Since that time, new technology may have emerged or new medical literature may have been published. This Medical Policy will be reviewed regularly and be updated as scientific and medical literature becomes available.



The automatic implantable cardioverter defibrillator (ICD) is a device designed to monitor a patient's heart rate, recognize ventricular fibrillation (VF) or ventricular tachycardia (VT), and deliver an electric shock to terminate these arrhythmias to reduce the risk of sudden death.


Indications for ICD implantation can be broadly subdivided into:

  1. secondary prevention, i.e., their use in patients who have experienced a potentially life-threatening episode of ventricular tachyarrhythmia (VT) (near sudden cardiac death); and
  2. primary prevention, i.e., their use in patients who are considered at high risk for sudden cardiac death but who have not yet experienced life-threatening VT or ventricular fibrillation (VF).


A totally subcutaneous ICD (S-ICD®) has been developed. This device does not employ transvenous leads and thus avoids the need for venous access and complications associated with the venous leads. Rather, the S-ICD® uses a subcutaneous electrode that is implanted adjacent to the left sternum. The electrodes sense the cardiac rhythm and deliver countershocks through the subcutaneous tissue of the chest wall.


On September 28, 2012, the S-ICD® system by Cameron Health, Inc. was approved by the FDA "to provide defibrillation therapy for the treatment of life-threatening ventricular tachyarrhythmias in patients who do not have symptomatic bradycardia, continual (incessant) ventricular tachycardia, or spontaneous frequently recurring ventricular tachycardia that is reliably terminated with anti-tachycardia pacing". Boston Scientific Corp. announced on March 17, 2015, that it received U.S. Food and Drug Administration approval, as well as the CE mark, for its Emblem™ S-ICD system. The Emblem is the next-generation S-ICD. According to the company, the Emblem device is 20% thinner than the S-ICD, and its battery will last 40% longer. The device is also enabled for remote patient management through the Latitude™ NXT Patient Management System.


As part of the S-ICD's 2012 marketing approval, FDA required Boston Scientific to conduct a 5-year, 1,600-patient postmarket study to assess long-term safety and performance, as well as possible differences in effectiveness between genders. That study is currently recruiting participants and has an estimated completion date of 2020. The RCT will study the efficacy and adverse effects of the subcutaneous and transvenous ICD in individuals with a Class I or IIa indication for ICD without an indication for pacing. Several other clinical trials are ongoing.


The first study on outcomes of an entirely subcutaneous ICD was published in 2010. This study described the development and testing of the device, including empiric evidence for the optimal placement of the subcutaneous electrode.


National Institute for Health and Care Excellence (NICE)

NICE published guidance in April 2013 on the insertion of a subcutaneous implantable defibrillator with the following guidance: Current evidence on the efficacy of the insertion of a subcutaneous implantable cardioverter defibrillator (ICD) for the prevention of sudden cardiac death in the short and medium term is adequate. Evidence on its safety in the short term is adequate but there are uncertainties about long-term durability. Therefore this procedure should only be used with special arrangements for clinical governance, consent and audit or research.


A Report of the American College of Cardiology Foundation Appropriate Use Criteria Task Force, Heart Rhythm Society, American Heart Association, American Society of Echocardiography, Heart Failure Society of America, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, and Society for Cardiovascular Magnetic Resonance

The report published in 2013 regarding the subcutaneous ICD stated: further study is necessary to determine whether benefits might outweigh risks in patients who currently appear to derive little benefit from ICD therapy due to comorbidities and competing mortality risks.


European Society of Cardiology

In a subcommittee of the European Society of Cardiology the following was reported:


Reported advantages and disadvantages of the S-ICD® system:

The advantages of the S-ICD are:

  1. The absence of leads within the heart and the preservation of central venous circulation is the main advantage making it a great alternative for children with congenital heart diseases or patients with no venous access who were unsuitable for transvenous ICD.
  2. There is no risk of vascular injury or pneumothorax.
  3. The risk of systemic infections appears to be very low, best in high risk cases of previous device infection, hemodialysis, chronic immunosuppression therapy immunodeficiencies, or artificial heart valves.
  4. Although pocket infections can occur with the S-ICD (5-10%, similar to transvenous devices) infection resolves with antibiotics in the majority of cases.
  5. Explantation is rarely necessary however explanting an S-ICD is much simpler and safer than endovascular lead extraction. Young patients with high lead failure rates due to an active lifestyle may especially benefit.
  6. The simplified implant procedure, with no need for fluoroscopy favors a more widespread use of a life-saving therapy, even in those centers without great experience in traditional surgical procedure, with less risk of serious complications.
  7. The S-ICD has cosmetic advantages despite its larger size, owing to the anatomic location in the lateral axilla: this location, rather than the anterior infraclavicular position is particularly appreciated by women.
  8. The device is well tolerated, no explantation due to patient discomfort has been noted.
  9. Another benefit is the lack of apparent myocardial damage despite greater shock intensity (80 J). Energy is actually distributed more evenly throughout the myocardium, with only 10% of delivered energy reaching cardiac myocytes: elevation of serum bio-markers of myocardial damage is lessened, and this may be particularly important in patients with ventricular dysfunction.


Described further are the limitations of the device:

  1. Pre-implantation screening is mandatory. Using a customised transparent plastic tool provided by the manufacturer, a modified “ad hoc” ECG skin electrode positioning is carried out to verify adequate sensing of subcutaneous signals, avoiding double counting of QRS or T wave oversensing (TWOS) in particular. Up to 7.4% of possible candidates would not be suitable for implant: hypertrophic cardiomyopathy, heavy weight, prolonged QRS duration and a R/T ratio <3 were independently associated with screening failure.
  2. Rates of inappropriate shocks are similar to those occuring with the transvenous ICD and range from 4 to 25% however the mechanisms are different. WIth the S-ICD, eighty per cent of inappropriate shocks are caused by TWOS, especially in congenital heart disease, Brugada and long QT syndromes, while in transvenous ICD, TWOS is involved in about 20% of cases. Accurate screening is possible even with acquisition of templates during exercise. Moreover about 5 to 10% of inappropriate shocks can be caused by muscular noise due to myopotentials (lead is placed over intercostal and pectoral muscles) but this problem may be overcome by reprogramming the sensing vector. Explantation can become necessary (5% in one study) when repeated shocks due to TWOS or noise occur despite different vectors programming.
  3. The risk for undersensing of true arrhythmias (i.e. VF with very low amplitude waves).
  4. Prolonged time to therapy compared with transvenous ICD (14-18” vs 7-8”)
  5. Inadequate shock efficacy on spontaneous clinical VT/VF (22). Indeed, there are still relatively few data regarding long term performance of the S-ICD in a “real world” scenario therefore larger experience and longer follow-up are required, nevertheless initial results are encouraging (no death can be attributed to device or lead failure in published studies).
  6. Other limitations are no pacing capability (with the exception of post-shock pacing) that also means no ATP nor resynchronisation therapy delivery (CRT).
  7. Remote monitoring and atrial tachyarrhythmias monitoring are not yet available.
  8. Pulse generator is larger, with anticipated life battery shorter than traditional devices (about 5 years).
  9. Costs are still high: The S-ICD cost is 4-6x than that of a single chamber transvenous ICD.


On the basis of provider consensus: There is a subset of the population that is unable to use the transvenous implantable cardioverter defibrillator (ICD). This population would qualify for implantation of the subcutaneous ICD, not based on device superiority or longevity, but strictly based on the inability to use the transvenous ICD.


Prior Approval:

Not Applicable



The implantation of the subcutaneous ICD (S-ICD) is considered medically necessary only for the following populations:

There must be a contraindication to a transvenous ICD due to one or more of the following:

  1. Lack of adequate vascular access (ie, need for chronic dialysis, current indwelling catheter) OR
  2. History of need for removal of a transvenous ICD due to a complication, with ongoing need for ICD therapy. OR
  3. Complex congenital heart disease causing vascular access challenge. OR
  4. Those with previous endocarditis or other cardiac infection


The following must also apply to the patient’s condition:

  1. Must have a medical indication for ICD therapy AND
  2. Do not have ventricular arrhythmias that are known or anticipated to respond to antitachycardia pacing including ventricular tachycardia AND
  3. Have no indication for antibradycardia pacing; (including no history of persistent bradycardia or frequent bradycardia)


There are currently no defined guidelines for the selection of a subcutaneous implantable cardioverter defibrillator (S-ICD) over a transvenous ICD (TV-ICD) system. The results from ongoing clinical studies will determine the S-ICD system's long-term performance, and better define suitable patient subpopulations where subcutaneous ICD would be a first line choice. Age alone, fear of complications, or fear of lead failure are not indications for using the subcutaneous ICD. Ongoing comparison studies need to define durability and superiority of the S-ICD over the transvenous ICD. Transvenous ICD remains the gold standard at this time.


Procedure Codes and Billing Guidelines:

To report provider services, use appropriate CPT* codes, Alpha Numeric (HCPCS level 2) codes, Revenue codes, and/or diagnosis codes.

  • 33270 Insertion or replacement of permanent subcutaneous implantable defibrillator system, with subcutaneous electrode, including defibrillation threshold evaluation, induction of arrhythmia, evaluation of sensing for arrhythmia termination, and programming or reprogramming of sensing or therapeutic parameters, when performed
  • 33271 Insertion of subcutaneous implantable defibrillator electrode


Selected References:

  • Bardy GH, Smith WM, Hood MA et al. An entirely subcutaneous implantable cardioverter-defibrillator. N. Engl. J. Med. 2010; 363(1):36-44.
  • Gold MR, Theuns DA, Knight BP et al. Head-to-head comparison of arrhythmia discrimination performance of subcutaneous and transvenous ICD arrhythmia detection algorithms: the START study. J. Cardiovasc. Electrophysiol. 2012; 23(4):359-66.
  • Jarman JW, Lascelles K, Wong T, Markides V, Clague JR, Till J: Clinical experience of entirely subcutaneous implantable cardioverter-defibrillators in children and adults: Cause for caution. Eur Heart J 2012;33:1351-1359
  • Pedersen SS, Lambiase P, Boersma LV, Murgatroyd F, Johansen JB, Reeve H, Stuart AG, Adragao P, Theuns DA: Evaluation of factors impacting clinical outcome and cost effectiveness of the S-ICD: Design and rationale of the EFFORTLESS S-ICD Registry. Pacing Clin Electrophysiol 2012;35:574-579
  • Blue Cross and Blue Shield Association Medical Policy Reference Manual Issue 5:2013. Accessed 6/18/13.
  • Lambiase PD, Barr C, Theuns DA et al. Worldwide experience with totally subcutaneous implantable defibrillator: early results from the EFFORTLESS S-ICD registry. Eur Heart J 2014;doi:10.1093/eurheartj/ehu112.
  • Jarman JW, Todd DM. United Kingdom national experience of entirely subcutaneous implantablecardioverter-defibrillator technology: important lessons to learn. Europace 2013;15:1158-1165.
  • NICE Interventional Procedures Guidance [IPG454}]. Insertion of a subcutaneous implantable cardioverter defibrillator for prevention of sudden cardiac death. 24 April 2013.
  • Who Should Receive the Subcutaneous Implanted Defibrillator? The Subcutaneous Implantable Cardioverter Defibrillator (ICD) Should Be Considered in all ICD Patients Who Do Not Require Pacing. Poole JE, Gold MR. Circ Arrhythm Electrophysiol. 2013 Dec 1;6(6):1236-45.
  • Evaluation of acute cardiac and chest wall damage after shocks with a subcutaneous implantable cardioverter defibrillator in Swine. Killingsworth CR, Melnick SB, Litovsky SH, Ideker RE, Walcott GP. Pacing Clin Electrophysiol. 2013 Oct;36(10):1265-72.
  • Which Patients Are Not Suitable for a Subcutaneous ICD: Incidence and Predictors of Failed QRS-T-Wave Morphology Screening. Olde Nordkamp LR, Warnaars JL, Kooiman KM, de Groot JR, Rosenmöller BR, Wilde AA, Knops RE. J Cardiovasc Electrophysiol. 2013 Dec 9. doi: 10.1111/jce.12343. [Epub ahead of print].
  • Who should receive the subcutaneous implanted defibrillator? Timing is not right to replace the transvenous implantable cardioverter defibrillator.  Acha MR, Milan D. Circ Arrhythm Electrophysiol. 2013 Dec 1;6(6):1246-51.
  • Evaluation oF FactORs ImpacTing CLinical Outcome and Cost EffectiveneSS of the S-ICD: design and rationale of the EFFORTLESS S-ICD Registry. Pedersen SS, Lambiase P, Boersma LV, Murgatroyd F, Johansen JB, Reeve H, Stuart AG, Adragao P, Theuns DA. Pacing Clin Electrophysiol. 2012 May;35(5):574-9.
  • Maria ED, Olaru A., Cappelli S. The subcutaneous defibrillator: who stands to benefit. An article from the e-journal of the ESC Council for Cardiology. Vol 12 No17, 04Mar2014.
  • Priori SG, Blomstrom-Lundqvist C, Mazzanti A, et al. 2015 ESC Guidelines for the management of patients with ventricular arrhythmias and the prevention of sudden cardiac death: The Task Force for the Management of Patients with Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death of the European Society of Cardiology (ESC)Endorsed by: Association for European Paediatric and Congenital Cardiology (AEPC). Eur Heart J. Nov 1 2015;36(41):2793-2867. PMID 26320108
  • Lambiase PD, Gold MR, Hood M, et al. Evaluation of subcutaneous ICD early performance in hypertrophic cardiomyopathy from the pooled EFFORTLESS and IDE cohorts. Heart Rhythm. 2016. PMID
  • Burke MC, Gold MR, Knight BP, et al. Safety and efficacy of the totally subcutaneous implantable defibrillator: 2- year results from a pooled analysis of the IDE Study and EFFORTLESS Registry. J Am Coll Cardiol. Apr 28 2015;65(16):1605-1615. PMID 25908064
  • Kobe J, Reinke F, Meyer C et al. Implantation and follow-up of totally subcutaneous versus  conventional implantable cardioverter-defibrillators: a multicenter case-control study. Heart Rhythm 2013; 10(1):29-36.
  • Weiss R, Knight BP, Gold MR et al. Safety and Efficacy of a Totally Subcutaneous Implantable-  Cardioverter Defibrillator. Circulation 2013; 128(9):944-53.
  • Providencia R, Kramer DB, Pimenta D, et al. Transvenous implantable cardioverter-defibrillator (ICD) lead performance: a meta-analysis of observational studies. J Am Heart Assoc. Nov 2015;4(11). PMID 26518666
  • Ray JC, Goodall HM, Pascual TE, Kusumoto FM. Implantable cardioverter defibrillators: state of the art. 7 April 2015 Volume 2015:6 Pages 29—41
  • Olde Nordkamp LR, Postema PG, Knops RE, et al. Implantable cardioverter-defibrillator harm in young patients with inherited arrhythmia syndromes: A systematic review and meta-analysis of inappropriate shocks and complications. Heart Rhythm. Feb 2016;13(2):443-454. PMID 26385533
  • Pettit SJ, McLean A, Colquhoun I, et al. Clinical experience of subcutaneous and transvenous implantable cardioverter defibrillators in children and teenagers. Pacing Clin Electrophysiol. 2013;36(12):1532-1538.
  • Haugaa KH, Tilz R, Boveda S, et al. Implantable cardioverter defibrillator use for primary prevention in ischaemic and non-ischaemic heart disease-indications in the post-DANISH trial era: Results of the European Heart Rhythm Association survey. Europace. 2017;19(4):660-664.
  • O'Gara PT, Kushner FG, Ascheim DD, et al. 2013 ACCF/AHA guideline for the management of ST-elevation myocardial infarction: A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol. 2013;61(4):e78-e140.


Policy History:

  • June 2018 - Interim review, Policy Revised
  • August 2017 - Annual review, Policy revised
  • August 2016 - Annual review, Policy revised
  • September 2015 - Annual review, Policy revised
  • October 2014 - Annual review, Policy revised
  • December 2013 - Annual review, Policy renewed
  • July 2013 - New Policy

Wellmark medical policies address the complex issue of technology assessment of new and emerging treatments, devices, drugs, etc.   They are developed to assist in administering plan benefits and constitute neither offers of coverage nor medical advice. Wellmark medical policies contain only a partial, general description of plan or program benefits and do not constitute a contract. Wellmark does not provide health care services and, therefore, cannot guarantee any results or outcomes. Participating providers are independent contractors in private practice and are neither employees nor agents of Wellmark or its affiliates. Treating providers are solely responsible for medical advice and treatment of members. Our medical policies may be updated and therefore are subject to change without notice.


*CPT® is a registered trademark of the American Medical Association.