Protocol. Biventricular Pacemakers (Cardiac Resynchronization Therapy) for the Treatment of Heart Failure



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Biventricular Pacemakers (Cardiac Resynchronization Therapy) for (20210) Medical Benefit Effective Date: 07/01/15 Next Review Date: 05/17 Preauthorization Yes Review Dates: 09/09, 01/10, 09/10, 07/11, 07/12, 09/12, 05/13, 05/14, 05/15, 05/16 Preauthorization is required. The following Protocol contains medical necessity criteria that apply for this service. The criteria are also applicable to services provided in the local Medicare Advantage operating area for those members, unless separate Medicare Advantage criteria are indicated. If the criteria are not met, reimbursement will be denied and the patient cannot be billed. Please note that payment for covered services is subject to eligibility and the limitations noted in the patient s contract at the time the services are rendered. Description Cardiac resynchronization therapy (CRT), which consists of synchronized pacing of the left and right ventricles, is intended to treat patients with heart failure and dyssynchronous ventricular contractions. Treatment involves placement of a device that paces both ventricles and which coordinates ventricular pacing to maximize cardiac pumping function and left ventricular ejection fraction (LVEF). Summary of Evidence Evidence from clinical trials and systematic reviews supports the benefit of cardiac resynchronization therapy (CRT) treatment for patients with New York Heart Association (NYHA) class III/IV heart failure. For this group, there are improvements in mortality, functional status, and quality of life. As a result, CRT treatment may be considered medically necessary for patients with NYHA class III/IV heart failure when criteria are met. For patients with milder heart failure, randomized controlled trial (RCT) evidence from at least one large, highquality trial reports a mortality benefit for patients with class II heart failure, but other RCTs do not report a mortality benefit. Several studies report a decrease in hospitalizations and mortality for class II or combined class I/II patients, but no studies provide evidence of treatment benefit on functional status or quality-of-life outcomes. Despite the lower level of evidence available for mild (class II) compared with advanced heart failure, it can be concluded that the benefit of CRT outweighs the risk for these patients. Therefore, CRT treatment may be considered medically necessary for class II heart failure patients who meet other clinical criteria for treatment. The evidence on class I heart failure is not sufficient to permit conclusions, as only a small number of class I patients have been included in some of the trials, and no benefit has been demonstrated for this specific subgroup. As a result, CRT is considered investigational for class I heart failure. Triple-site (triventricular) CRT, using an additional pacing lead, is in preliminary testing with only a small amount of available evidence and is considered investigational as an alternative to conventional CRT. Treatment of patients with atrial fibrillation (AF) and heart failure is controversial. Available evidence establishes that patients with heart failure probably do not derive the same magnitude of benefit as do patients with sinus rhythm and that CRT with atrioventricular (AV) nodal ablation is probably superior to CRT without AV nodal ablation in patients with heart failure. However, the evidence is insufficient to determine whether CRT treatment is superior to no treatment for this patient group. In addition, clinical input in 2012 was mixed as to Page 1 of 9

whether patients with AF should be treated with CRT. Therefore, CRT remains investigational for patients with AF. The available evidence indicates that benefit is concentrated in patients with a QRS duration of more than 150 ms or in patients with a left bundle branch block (LBBB). Conversely, patients with a QRS duration of 120 to 150 ms do not benefit. Although clinical input in 2012 demonstrated support for continued use of QRS threshold of 120 ms, rather than restricting treatment to patients with QRS of more than 150 ms, the evolving evidence since 2012 supports limiting CRT to patients with widened QRS complexes or LBBB. Other factors for selecting patients, such as ventricular dyssynchrony on echocardiography, have not been shown to be good discriminators of responders versus nonresponders. For patients who have some degree of heart failure and who are candidates for a pacemaker, evidence from one RCT suggests that biventricular pacing is associated with reduced urgent care visits and hospitalizations for heart failure. Therefore, CRT may be considered medically necessary for patients with left ventricular ejection fraction of 50% or less and AV block who are likely to require a high degree of ventricular pacing, as an alternative to right ventricular pacing. For patients without heart failure but who require a pacemaker, randomized trials are underway to determine whether biventricular pacing is associated with improved outcomes. Policy Biventricular pacemakers with or without an accompanying implantable cardiac defibrillator (i.e., a combined biventricular pacemaker/icd) may be considered medically necessary as a treatment of heart failure in patients who meet all of the following criteria: New York Heart Association class III or IV Left ventricular ejection fraction 35% Sinus rhythm Patients treated with guideline-directed medical therapy (see Policy Guidelines) AND Either left bundle branch block OR QRS duration 150 ms* New York Heart Association class II Left ventricular ejection fraction 30% Sinus rhythm Patients treated with a guideline-directed medical therapy (see Policy Guidelines) AND Either Left bundle branch block, OR QRS duration 150 ms* * U.S. Food and Drug Administration (FDA) labeled indications for QRS duration vary by device. For some devices, FDA approval is based on QRS duration of 130 (e.g., InSync device), while for others, it is based on QRS duration 120 ms (e.g., CONTAK CD CRT-D System). These differences in QRS duration arise from differences in the eligibility criteria in the trials on which the FDA approval is based. For patients who do not meet the criteria outlined above, but who have an indication for a ventricular pacemaker, biventricular pacemakers with or without an accompanying implantable cardiac defibrillator (i.e., a Page 2 of 9

combined biventricular pacemaker/icd) may be considered medically necessary as an alternative to a right ventricular pacemaker in patients who meet all of the following criteria: NYHA class I, II, III, or IV heart failure; Left ventricular ejection fraction 50%; The presence of atrioventricular block with requirement for a high percentage of ventricular pacing (see Policy Guidelines); and Patients treated with guideline-directed medical therapy (see Policy Guidelines). Biventricular pacemakers, with or without an accompanying implantable cardiac defibrillator (i.e., a combined biventricular pacemaker/icd), are considered investigational as a treatment for patients with NYHA class I heart failure who do not meet the above criteria. Biventricular pacemakers, with or without an accompanying implantable cardiac defibrillator (i.e., a combined biventricular pacemaker/icd), are considered investigational as a treatment for heart failure in patients with atrial fibrillation who do not meet the above criteria. An intrathoracic fluid monitoring sensor is considered investigational as a component of a biventricular pacemaker. Triple-site (triventricular) CRT, using an additional pacing lead, is considered investigational. Policy Guidelines Policy Definitions AV block with a requirement for a high percentage of ventricular pacing is considered to be present when there is either: 3 rd degree AV block; or 2 nd degree AV block or a PR interval of 300 ms or more when paced at 100 beats per minute Guideline-directed medical therapy for heart failure is outlined in 2013 American College of Cardiology Foundation/American Heart Association guidelines for the management of heart failure. 1 Background It is estimated that 20% to 30% of patients with heart failure have intraventricular conduction disorders, resulting in a contraction pattern that is not coordinated and a wide QRS interval on the electrocardiogram. This abnormality appears to be associated with increased morbidity and mortality. Biventricular pacemakers using three leads (one in the right atrium, one in each ventricle), also known as CRT, have been investigated as a technique to coordinate the contraction of the ventricles, thus improving patients hemodynamic status. Several types of CRT devices are available, including those that incorporate biventricular pacing into automatic implantable cardiac defibrillators (ICDs), stand-alone biventricular pacemakers, and biventricular pacemakers that incorporate fluid monitoring via bioimpedance. Originally developed CRT devices typically used two ventricular leads for biventricular pacing. Devices and implantation techniques have been developed to allow for multisite pacing, with the goal of improving CRT response. This may be accomplished in one of two ways: through the use of multiple leads within the coronary Page 3 of 9

sinus (triventricular pacing) or through the use of multipolar left ventricular pacing leads, which can deliver pacing stimuli at multiple sites. Regulatory Status There are numerous CRT devices, combined ICD-CRT devices (CRT-D), and combined CRT and fluid monitoring devices. Some of the devices are discussed here. For example, a stand-alone biventricular pacemaker (InSync Biventricular Pacing System; Medtronic) has received approval by FDA for the treatment of patients with NYHA class III or IV heart failure, on a stable pharmacologic regimen, who also have a QRS duration of 130 ms or longer and a LVEF of 35% or less. Both Guidant (CONTAK CD CRT-D System) and Medtronic (InSync ICD Model 7272) have received FDA approval for combined cardiac resynchronization therapy defibrillators for patients at high risk of sudden cardiac death due to ventricular arrhythmias and who have NYHA class III or IV heart failure with LVEF of 35% or less, QRS duration 130 ms or longer ( 120 ms for the Guidant device), and remain symptomatic despite a stable, optimal heart failure drug therapy. In 2006, Biotronik Inc. received FDA approval for its combined ICD-CRT device with ventricular pacing leads (Tupos LV/ATx CRT-D/Kronos LV-T CRT-D systems 2 ); in 2013, the company received FDA approval for updated ICD-CRT devices (Ilesto/Iforia series). 3 In September 2010, FDA expanded the indications for some CRT devices to include patients with class I and II heart failure. Based on data from the MADIT-CRT study, indications for three Guidant (Boston Scientific) CRTdefibrillator devices (Cognis, Livian, and Contak Renewal devices) were expanded to include patients with heart failure who receive stable optimal pharmacologic therapy for heart failure and who meet any one of the following classifications 4 : Moderate-to-severe heart failure (NYHA class III-IV) with ejection fraction less than 35% and QRS duration greater than 120 ms. Left bundle branch block with QRS greater than or equal to 130 ms, ejection fraction less than 30%, and mild (NYHA class II) ischemic or nonischemic heart failure or asymptomatic (NYHA class I) ischemic heart failure. In April 2014, FDA further expanded the indications for multiple Medtronic CRT devices to include patients with NYHA functional class I, II, or III heart failure, who have LVEF of 50% or less on stable, optimal heart failure medical therapy, if indicated, and have AV block that is expected to require a high percentage of ventricular pacing that cannot be managed with algorithms to minimize right ventricular pacing. The expanded indication was based on data from the BLOCK-HF study, a Medtronic-sponsored RCT to evaluate the use of CRT in patients with NYHA class I, II, or III heart failure, LVEF 50%, and AV block. Several CRT devices incorporate a fourth lead, providing quadripolar pacing. The Medtronic Viva Quad XT and the Viva Quad S incorporate a fourth lead, the Medtronic Attain Performa left ventricular lead, which received clearance for marketing from FDA in August 2014. The Dynagen X4 and Inogen X4 devices (Boston Scientific, Marlborough, MA) incorporate a fourth lead. Other CRT devices with quadripolar leads have been approved for use outside of the United States (e.g., St. Jude Quartet left ventricular lead). Multiple devices manufactured by Medtronic combine a CRT with the OptiVol monitoring system. For example, in 2005, the InSync Sentry system received FDA approval through the supplemental premarket approval process. This combined biventricular pacemaker/icd is also equipped to monitor intrathoracic fluid levels using bioimpedance technology, referred to as OptiVol Fluid Status Monitoring. Bioimpedance measures, defined as the electrical resistance of tissue to flow of current, are performed many times per day using a vector from the right ventricular coil on the lead in the right side of the heart to the implanted pacemaker devices; changes in bioimpedance reflect intrathoracic fluid status and are evaluated based on a computer algorithm. For example, changes in a patient s daily average of intrathoracic bioimpedance can be monitored; differences in the daily average compared with a baseline are reported as the OptiVol Fluid Index. It has been proposed that these data Page 4 of 9

may be used as an early warning system of cardiac decompensation or to provide additional feedback, enabling a physician to further tailor medical therapy. FDA product code: NIK. Related Protocol Implantable Cardioverter Defibrillator Services that are the subject of a clinical trial do not meet our Technology Assessment Protocol criteria and are considered investigational. For explanation of experimental and investigational, please refer to the Technology Assessment Protocol. It is expected that only appropriate and medically necessary services will be rendered. We reserve the right to conduct prepayment and postpayment reviews to assess the medical appropriateness of the above-referenced procedures. Some of this Protocol may not pertain to the patients you provide care to, as it may relate to products that are not available in your geographic area. References We are not responsible for the continuing viability of web site addresses that may be listed in any references below. 1. Writing Committee M, Yancy CW, Jessup M, et al. 2013 ACCF/AHA guideline for the management of heart failure: a report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines. Circulation. Oct 15 2013; 128(16):e240-327. PMID 23741058 2. FDA. Summary of Safety and Effectiveness Data: Tupos LV/ATx CRT-D, Kronos LV-T CRT-D. 2006; http://www.accessdata.fda.gov/cdrh_docs/pdf5/p050023b.pdf. Accessed February 23, 2015. 3. FDA. Approval Order: Biotronic PMA P050023. 2013; http://www.accessdata.fda.gov/cdrh_docs/pdf5/p050023s058a.pdf. Accessed February 23, 2015. 4. Administration FaD. Summary of Safety and Effectiveness Data: Cardiac Resynchronization Therapy Defibrillator (CRT-D). 2010; http://www.accessdata.fda.gov/cdrh_docs/pdf/p010012s230b.pdf. Accessed March 30, 2015. 5. Hunt SA. ACC/AHA 2005 guideline update for the diagnosis and management of chronic heart failure in the adult: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Update the 2001 Guidelines for the Evaluation and Management of Heart Failure). J Am Coll Cardiol. Sep 20 2005; 46(6):e1-82. PMID 16168273 6. Cardiac resynchronization therapy for mild congestive heart failure. Blue Cross and Blue Shield Association Technology Evaluation Center TEC Assessment Program. 2009; 24(8). 7. Bristow MR, Saxon LA, Boehmer J, et al. Cardiac-resynchronization therapy with or without an implantable defibrillator in advanced chronic heart failure. N Engl J Med. May 20, 2004; 350(21):2140-2150. PMID 15152059 Page 5 of 9

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