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Cardiac Hemodynamic Monitoring for the Management of Heart Failure in the Outpatient Setting

Policy Number: MP-441

Latest Review Date: May 2019

Category: Medicine                                                               

Policy Grade:  B

Description of Procedure or Service:

A variety of outpatient cardiac hemodynamic monitoring devices are intended to improve quality of life and reduce morbidity for patients with heart failure by decreasing episodes of acute decompensation. Monitors can identify physiologic changes that precede clinical symptoms and thus allow preventive intervention.  These devices operate through a variety of mechanisms, including implantable pressure sensors, thoracic bioimpedance measurement, inert gas rebreathing, and estimation of left ventricular end diastolic pressure by arterial pressure during the Valsalva maneuver.

Chronic Heart Failure

Patients with chronic heart failure are at risk of developing acute decompensated heart failure, often requiring hospital admission. Patients with a history of acute decompensation have the additional risk of future episodes of decompensation, and death. Reasons for the transition from a stable, chronic state to an acute, decompensated state include disease progression, as well as acute events such as coronary ischemia and dysrhythmias. While precipitating factors are frequently not identified, the most common preventable cause is noncompliance with medication and dietary regimens.  

Management

Strategies for reducing decompensation, and thus the need for hospitalization, are aimed at early identification of patients at risk for imminent decompensation. Programs for early identification of heart failure are characterized by frequent contact with patients to review signs and symptoms with a healthcare provider and with education or adjustment of medications as appropriate. These encounters may occur face-to-face in the office or at home, or via cellular or computed technology.

Precise measurement of cardiac hemodynamics is often employed in the intensive care setting to carefully manage fluid status in acutely decompensated heart failure. Transthoracic echocardiography, transesophageal echocardiography (TEE), and Doppler ultrasound are noninvasive methods for monitoring cardiac output on an intermittent basis for the more stable patient but are not addressed herein.  A variety of biomarkers and radiological techniques may be used for dyspnea when the diagnosis of acute decompensated heart failure is uncertain.

The criterion standard for hemodynamic monitoring is pulmonary artery catheters and central venous pressure catheters. However, they are invasive, inaccurate and inconsistent in predicting fluid responsiveness. Several studies have demonstrated that it fails to improve outcome in critically ill patients and may be associated with harm. To overcome these limitations, multiple techniques and devices have been developed that use complex imaging technology and computer algorithms to estimate fluid responsiveness, volume status, cardiac output and tissue perfusion. Many of these are intended to be used in outpatient setting but can potentially be also used in the emergency department, intensive care unit, and operating room. Four methods are reviewed here: implantable pressure monitoring devices, thoracic bioimpedance, inert gas rebreathing, and arterial waveform during the Valsalva maneuver. The use of last 3 is not widespread because of several limitations including use proprietary technology making it difficult to confirm their validity and no large randomized controlled trials have been conducted to evaluate treatment decisions guided by these hemodynamic monitors.

This policy refers only to the use of stand-alone cardiac output measurement devices designed for use in ambulatory care and outpatient settings. The use of cardiac hemodynamic monitors or intrathoracic fluid monitors that are integrated into other implantable cardiac devices, including implantable cardioverter defibrillators, cardiac resynchronization therapy devices, and cardiac pacing devices, is addressed in medical policy # 055 – Biventricular Pacemakers (Cardiac Resynchronization Therapy) for the Treatment of Heart Failure.

Policy:

In the ambulatory care and outpatient setting, cardiac hemodynamic monitoring for the management of heart failure utilizing thoracic bioimpedance, inert gas rebreathing, arterial pressure/Valsalva, and implantable direct pressure monitoring of the pulmonary artery is considered not medically necessary and investigational.

Key Points:

The most recent literature review was updated through April 2, 2019.

For the first indication, because we have direct evidence from a large randomized controlled trial (RCT), we will focus on it and assess the evidence it provides on clinical utility. Evidence reviews assess the clinical evidence to determine whether the use of a technology improves the net health outcome. Broadly defined, health outcomes are length of life, quality of life, and ability to function; including benefits and harms. Every clinical condition has specific outcomes that are important to patients and to managing the course of that condition. Validated outcome measures are necessary to ascertain whether a condition improves or worsens; and whether the magnitude of that change is clinically significant. The net health outcome is a balance of benefits and harms.

To assess whether the evidence is sufficient to draw conclusions about the net health outcome of a technology, 2 domains are examined: the relevance and the quality and credibility. To be relevant, studies must represent one or more intended clinical use of the technology in the intended population and compare an effective and appropriate alternative at a comparable intensity. For some conditions, the alternative will be supportive care or surveillance. The quality and credibility of the evidence depend on study design and conduct, minimizing bias and confounding that can generate incorrect findings. The RCT is preferred to assess efficacy; however, in some circumstances, nonrandomized studies may be adequate. RCTs are rarely large enough or long enough to capture less common adverse events and long-term effects. Other types of studies can be used for these purposes and to assess generalizability to broader clinical populations and settings of clinical practice.

For indications 2, 3, and 4, we assess the evidence as a medical test. Evidence reviews assess whether a medical test is clinically useful. A useful test provides information to make a clinical management decision that improves the net health outcome. That is, the balance benefits and harms are better when the test is used to manage the condition than when another test or no test is used to manage the condition.

The first step in assessing a medical test is to formulate the clinical context and purpose of the test. The test must be technically reliable, clinically valid, and clinically useful for that purpose. Evidence reviews assess the evidence on whether a test is clinically valid and clinically useful. Technical reliability is outside the scope of these reviews, and credible information on technical reliability is available from other sources.

Implantable Direct Pulmonary Artery Pressure Measurement Methods

Clinical Context and Therapy Purpose

The purpose of the CardioMEMS system in patients who have heart failure is to provide remote monitoring for early symptoms of heart failure in order to modify therapy and prevent or reduce hospitalization.

The question addressed in this evidence review is: does use of an implantable pulmonary artery sensor device (CardioMEMS) improve health outcomes in individuals with heart failure in the outpatient setting?

The following PICOTS were used to select literature to inform this review.

Patients

The relevant population(s) of interest are patients with NYHA Class III heart failure who have had a hospitalization in the past year.

Interventions

Left ventricular end-diastolic pressure (LVEDP) can be approximated by direct pressure measurement of an implantable sensor in the pulmonary artery wall or right ventricular outflow tract. The sensor is implanted via right heart catheterization and transmits pressure readings wirelessly to external monitors. One device, the CardioMEMS Champion Heart Failure Monitoring System, has approval from the U.S. Food and Drug Administration (FDA) for the ambulatory management of heart failure patient. The CardioMEMS device is implanted using a heart catheter system fed through the femoral vein and generally requires patients have an overnight hospital admission for observation after implantation.

Comparators

The comparator of interest is standard clinical care without testing.

Outcomes

The International Consortium for Health Outcomes Measurement (ICHOM) has identified 3 domains of outcomes for a standard outcome set for patients with heart failure.

1. Survival and disease control (i.e., mortality)

2. Functioning and disease control (i.e., symptom control including dyspnea, fatigue and tiredness, disturbed sleep, and peripheral edema, activities of daily living including health-related quality of life, maximum physical exertion, independence and psychosocial health including depression and anxiety, confidence and self-esteem)

3. Burden of care to patient (i.e., hospital visits including admissions and appointments, treatment side effects, complications)

The Heart Failure Association of the European Society of Cardiology has published a consensus document on heart failure outcome in clinical trials. They likewise categorize important outcomes for clinical trials as mortality outcomes (all-cause and cause-specific), morbidity and clinical composites (including hospitalizations, worsening of heart failure, implantable cardioverter device shocks) and symptoms and patient-reported outcomes. The consensus document recommends that hospitalization for heart failure be defined as a hospitalization requiring at least an overnight stay caused by substantive worsening of symptoms and/or signs requiring augmentation of therapy.

Measurements of maximal oxygen consumption during exercise (MVO2), the 6 minute walk test (6MWT), stair climb test, Short Physical Performance Battery (SPPB) or hand-grip strength are measures of function.

Patient-reported outcome measures include the Kansas City Cardiomyopathy Questionnaire (KCCQ), the New York Heart Association (NYHA) Functional Classification, Minnesota Living with Heart Failure Questionnaire (MLWHFQ).

Study Selection Criteria

Methodologically credible studies were selected using the following principles.

1. Comparative controlled prospective trials were sought, with preference for randomized controlled trials.

2. In the absence of such trials, comparative observational studies were sought, with preference for prospective studies.

3. To assess longer term outcomes and adverse effects, single-arm studies that capture longer periods of follow up and/or larger populations will be considered.

4. Larger sample size studies and longer duration studies are preferred.

5. Studies with duplicative or overlapping populations were excluded.

Randomized Controlled Trials

Abraham et al (2011, 2016) reported on the results of the CHAMPION single-blind RCT in which all enrolled patients were implanted with the CardioMEMS device. Patients were randomized to CardioMEMS group, in which daily uploaded pulmonary artery pressures were used to guide medical therapy, or to the control group, in which daily uploaded pressures were not made available to investigators and they continued to receive standard of care management, which included drug changes in response to patients’ clinical signs and symptoms. An independent clinical endpoints committee, blinded to the treatment groups, reviewed abstracted clinical data and determined if a hospitalization was related to heart failure hospitalization. The randomized phase ended when the last patient enrolled completed at least 6 months of study follow-up (average, 18 months) and was followed by an open access phase during which investigators had access to pulmonary artery pressure for all patients (former control and treatment group). The open access phase lasted for an average of 13 months. In the randomized phase of the trial, if the investigator did not document a medication change(s) in response to an abnormal PA pressure elevation, a remote CardioMEMS nurse could send communications to investigator related to clinical management. No such activity occurred in the nonrandomized phase. Trial characteristics and results are summarized in Tables 1 and 2. The trial met its primary efficacy end point with a statistically significant 28% relative reduction in the rate of heart failure‒related hospitalizations at 6 months. However, the members of the FDA advisory committee in 2011 were unable to distinguish the effect of the device from the effect of nurse communications and as such FDA denied the approval of CardioMEMS and requested additional clarification from the manufacturer. Subsequently, the FDA held a second Advisory committee meeting in 2013 and reviewed additional data (including open-access phase) to address the previous concerns related to impact of nurse communication on the CHMAPION trial.

The 2 major limitations in the early data were related to potential impact of nurse communication and lack of treatment effect in women.

The sponsor conducted multiple analyses to address the impact of nurse intervention on heart failure related hospitalizations that included (1) an independent audit of all nurse communication to estimate quantitatively the number of hospitalization that could have potentially be influenced by nurse communication, (2) using a propensity-based score matching approach to match patients in the CardioMEMS group that did not receive nurse communications and match them to control based, (3) compare if the new knowledge of pulmonary arterial pressure in the former control during the open-access phase led to reduction in heart failure related hospitalizations, (4) compare if the maintained access to pulmonary artery pressures in the treatment group during the open-access phase was accompanied by maintenance of a reduced rate of heart failure hospitalizations, and (5) compare if similar access to pulmonary artery pressures in the former control group and treatment group during the open access phase is associated with similar rates of heart failure related hospitalizations. FDA concluded that all such analysis have methodologic limitations. Propensity matching cannot balance unmeasured characteristics and confounders and therefore conclusions drawn from propensity analysis are not definitive. While FDA concluded that the third-party audit of nurse communication was valid, it was difficult to estimate accurately how many HFR hospitalizations were avoided by the nurse communications. FDA stated that the longitudinal analyses (see 3 to 5 above) were the most useful in terms of supporting the effectiveness of the device. Therefore, only data from analyses 3 to 5 is summarized in Table 3 and discussed next. It is important to acknowledge that all such analyses were post hoc and were conducted with the intention to test the robustness of potentially biased results of the RCT and therefore results from these analyses should be evaluated to assess consistency and not as independent source of evidence to support efficacy. As stated in Table 3, the longitudinal analyses of individual patient data showed that the device appears to be associated with reducing HFR hospitalization rate. However, there are important study limitations notably that subject dropouts were not random and patient risk profile could have changed from randomized phase to open access phase. In the open access phase, 93 (34%) of 270 subjects in treatment group and 110 (39%) of 280 subjects in control group remained in the analysis.

According to FDA documents, the apparent lack of reduction in heart failure-related hospitalization in women was a result of greater number of deaths early in the trial among women in the control group and this early mortality resulted in a competing risk for future heart failure hospitalizations. While both FDA and sponsor conducted multiple analyses to understand device effectiveness in women but FDA statisticians concluded that such analyses did not provide clarity in delineating limited treatment effect in women. The effectiveness of CardioMEMS in women may be clarified from the results of a postmarketing study that is currently ongoing and proposes to enroll at least 35% (n=420) women of the enrollment (n=1200).

Other subgroup analysis of CHAMPION trial in patients with reduced ejection fraction, preserved ejection fraction, Medicare-eligible patients, and patients with chronic obstructive pulmonary disease (COPD) are not discussed in this evidence review.

Table 1. Summary of Key RCT Characteristics

Author; Trial

Countries

Sites

Dates

Participants

Interventions

Active

Comparator

Abraham et al (2011, 2016); CHAMPION

U.S.

64

2007 - 2009

  • At least 1 previous HFH in the past 12 mo and NYHA class III HF for at least 3 mo
  • 40% patients from academic setting and 60% from community setting

Disease management by daily measurement of pulmonary artery pressures (via CardioMEMS) plus standard of care (n=270)

Disease management by standard of care alone (n=280)

HF: heart failure; HFH: heart failure hospitalization; NYHA: New York Heart Association.

Table 2. Summary of Key RCT Results

Study

HFH,n (events per patient per 6mo)

HFH, n (events per patient per 12 mo)

Device- or System Related Complications at 6 Months, n (%)

Device- or System Related Complications at 12 Months, n (%)

Pressure-Sensor Failures at 6 or 12 Months

Abraham et al (2011, 2016); CHAMPION

550

550

550

550

550

CardioMEMS

84 (0.32)

182 (0.46)

3 (1)

0

0

Control

120 (0.44)

279 (0.68)

3 (1)

0

0

HR (95% CI)

0.72 (0.60 to 0.85)

0.67 (0.55 to 0.80)

NA

NA

NA

NNT (95% CI)

8 (not reported)

4 (not reported)

NA

NA

CI: confidence interval; HFH: heart failure hospitalization; HR: hazard ratio; NNT: number needed to treat.

Table 3. Summary of Additional Analyses of the CHAMPION RCT

Trial Period

Randomized Group

CardioMEMS Data Available

Nurse Communications

Comparison

HR for HFH (95%CI)

Randomized access

Treatment

Yes

Yes

Former control to control

0.52(0.40 to 0.69)

Control

No

No

Former treatment to treatment

0.93 (0.70 to 1.22)

Open access

Former control

Yes

No

Former control to former treatment

0.80 (0.56 to 1.14)

Former treatment

Yes

No

Adapted from Abraham et al (2016) and FDA (2013). CI: confidence interval; HFH: heart failure hospitalization; HR: hazard ratio

Table 4. Relevance Gaps

Study; Trial

Population

Intervention

Comparator

Outcomes

Follow-up

Abraham et al (2011, 2016); CHAMPION

1.None

1. Delivery not similar intensity as comparator. Treatment group received additional nurse communication for enhanced protocol compliance. Trial intention was to assess physician’s ability to use PA pressure information and not capabilities of sponsor’s nursing staff to monitor and correct physician directed therapy.

1.None

1.None

1.None

The evidence gaps stated in this table are those notable in the current review; this is not a comprehensive gaps assessment. PA: pulmonary artery. a Population key: 1. Intended use population unclear; 2. Clinical context is unclear; 3. Study population is unclear; 4. Study population not representative of intended use. b Intervention key: 1. Not clearly defined; 2. Version used unclear; 3. Delivery not similar intensity as comparator; 4.Not the intervention of interest. c Comparator key: 1. Not clearly defined; 2. Not standard or optimal; 3. Delivery not similar intensity as intervention; 4. Not delivered effectively. d Outcomes key: 1. Key health outcomes not addressed; 2. Physiologic measures, not validated surrogates; 3. No CONSORT reporting of harms; 4. Not establish and validated measurements; 5. Clinical significant difference not prespecified; 6. Clinical significant difference not supported. e Follow-Up key: 1. Not sufficient duration for benefit; 2. Not sufficient duration for harms.

Table 5. Study Design and Conduct Gaps

Study

Allocation

Blinding

Selective Reporting

Follow-Up

Power

Abraham (2011, 2016); CHAMPION

1.None

1.Physicians not blinded to treatment assignment but outcome assessment was independent and blinded

1.None

1.None

1.None

The evidence gaps stated in this table are those notable in the current review; this is not a comprehensive gaps assessment. a Allocation key: 1. Participants not randomly allocated; 2. Allocation not concealed; 3. Allocation concealment unclear; 4. Inadequate control for selection bias. b Blinding key: 1. Not blinded to treatment assignment; 2. Not blinded outcome assessment; 3. Outcome assessed by treating physician. c Selective Reporting key: 1. Not registered; 2. Evidence of selective reporting; 3. Evidence of selective publication. d Follow-Up key: 1. High loss to follow-up or missing data; 2. Inadequate handling of missing data; 3. High number of crossovers; 4. Inadequate handling of crossovers; 5. Inappropriate exclusions; 6. Not intent to treat analysis (per protocol for noninferiority trials). e Power key: 1. Power calculations not reported; 2. Power not calculated for primary outcome; 3. Power not based on clinically important difference. f Statistical key: 1. Intervention is not appropriate for outcome type: (a) continuous; (b) binary; (c) time to event; 2. Intervention is not appropriate for multiple observations per patient; 3. Confidence intervals and/or p values not reported; 4. Comparative treatment effects not calculated.

Nonrandomized Studies

As previously described in the selection criteria, studies will be included here to assess longer term outcomes and adverse effects if they capture longer periods of follow up and/or larger populations than the RCTs.

Desai et al (2017) published a retrospective cohort study of Medicare administrative claims data for individuals who received the CardioMEMS device following FDA approval. Of 1935 Medicare enrollees who underwent implantation of the device, 1114 were continuously enrolled and had evaluable data for at least 6 months prior to, and following, implantation. A subset of 480 enrollees had complete data for 12 months before and after implantation. Study characteristics and results are summarized in Tables 6 and 7. The cumulative incidence of heart failure−related hospitalizations was significantly lower in the postimplantation period compared with preimplantation period at both 6- and 12-month follow-ups. Limitations of this pre-post retrospective study include lack of data regarding medical history, ejection fraction, indication for implantation and possible confounding due to amplified touchpoints with the healthcare system necessitated by the device’s implantation.

Vaduganathan (2017) analyzed mandatory and voluntary reports of device-related malfunctions reported to FDA to identify CardioMEMS HF System−related adverse events within the first 3 years of FDA approval. From among the more than 5500 CardioMEMS implants in the first 3 years, there were 155 adverse event reports covering 177 distinct adverse events for a rate of about 2.8%. There were 28 reports of pulmonary artery injury/hemoptysis (0.5%) that included 14 intensive care unit stays, 7 intubations, and 6 deaths. Sensor failure, malfunction, or migration occurred in 46 cases, of which 35 required recalibrations. Compared with a 2.8% event rate reported in this analysis, the serious adverse event rate in CHAMPION trial was 2.6% with 575 implant attempts, including 1 case of pulmonary artery injury and 2 deaths. Limitation of the current analysis primarily included lack of adjudication and limited clinical data.

Table 6. Summary of Key Nonrandomized Study Characteristics

Author

Study Type

Country/Institution

Dates

Participants

Treatment

Follow-Up

Desai et al (2017)

Retrospective cohort

U.S./Medicare

2014- 2015

Individuals with inpatient CPT codes consistent with use of procedure

CardioMEMS implant

2 cohorts:

• 6-mo preimplant and postimplant data (n=1114)

• 12-mo preimplant and postimplant data (n=480)

Vaduganathan (2017)

Postmarketing surveillance study

U.S./FDA and Abbott

2014- 2017

Individuals reporting CardioMEMS-related adverse event

CardioMEMS implant

Not applicable

FDA: Food and Drug Administration.

Table 7. Summary of Key Nonrandomized Study Results

Study

HFH at 6 months

HFH at 12 months

Safety

Desal et al (2017)

1114

480

-

Preimplant, n

1020

696

-

Postimplant, n

381

300

-

HR (95% CI);p

0.55 (0.49 to 0.61); <0.001

0.66 (0.57 to 0.76); <0.001

-

Vaduganathan et al (2017)

5500 estimated individuals who received CardioMEMS

AE cohort identified from MAUDE database

-

-

155 (2.8%) AEs; 28 pulmonary artery injury or hemoptysis (0.5%), and 22 deaths (0.4%)

AE: adverse event; CI: confidence interval; HFH: heart failure hospitalization; HR: hazard ratio.

Case Series

Heywood et al (2017) reported pulmonary artery pressure data of first 2000 consecutive patients with at least 6 months of follow-up that were implanted with CardioMEMS. No clinical data was reported except for PA measurement. Study characteristics and results are summarized in Tables 8 and 9. The mean age of the cohort enrolled was 70 years and the mean follow-up period was 333 days. There was a median of 1.2 days between remote pressure transmissions and greater than 98% weekly use of the system, demonstrating a high level of adherence.

Table 8. Summary of Key Case Series Characteristics

Author

Country/institution

Participants

Treatment Delivery

Follow-Up (SD)

Heywood et al (2010)

U.S./ Abbott

First 2000 individuals who received CardioMEMS with followup data for a minimum of 6 mo

CardioMEMS

333 (125) d

Table 9. Summary of Key Case Series Results

Author

Treatment

AUC (mm Hg day)

Adherence

Heywood et al (2010)

CardioMEMS device

  • -32.8 mm Hg/d (1 mo)
  • -156.2 mm Hg/d (3 mo)
  • −434.0 mm Hg/d (6 mo)
  • Median days between transmissions: 1.07 d (first 30 d) and 1.27 days (after 6 mo)
  • Use of the system: 98.6% (IQR, 82.9%-100.0%)

AUC: area under the curve; IQR: interquartile range

Section Summary: CardioMEMS Device

The pivotal CHAMPION RCT reported a statistically significant decrease in heart failure-related hospitalizations in patients implanted with CardioMEMS device compared with usual care. However, the results were potentially biased in favor of the treatment group due to use of additional nurse communication to enhance protocol compliance with the device. The intention of the trial was to assess the physician’s ability to use pulmonary artery pressure information and not the capabilities of the sponsor’s nursing staff to monitor and correct physician directed therapy. The manufacture conducted multiple analyses to address the issue of potential bias from the nurse interventions. These were reviewed favorably by the FDA. While these analyses demonstrated consistency of benefit from the CardioMEMS device, all such analyses have methodologic limitations. With greater adoption of this technology, it is likely to be used by a broader group of clinicians with variable training in the actual procedure and used in patients at a higher risk as compared with the CHAMPION trial. Early safety data are suggestive of a higher rate of procedural complications, particularly related to pulmonary artery injury. Given that the intervention is invasive, intended to be used for a highly prevalent condition, in the light of limited safety data, lack of demonstrable mortality benefit and pending questions related to its benefit for reduction in hospitalization, the net benefit remains uncertain. Many of these issues may be clarified from the results of an ongoing postmarketing study that is currently ongoing and proposes to enroll 1200 patients with at least 35% women.

Noninvasive Thoracic Bioimpedance/Impedance Cardiography (ICG)

Clinical Context and Test Purpose

The purpose of thoracic bioimpedance/impedance cardiography in patients who have heart failure in an outpatient setting is to (1) guide volume management, (2) identify physiologic changes that precede clinical symptoms and thus allow preventive interventions, and (3) prevent hospitalizations.

The question addressed in this evidence review is: Does use of thoracic bioimpedance/impedance

cardiography improve health outcomes in individuals with heart failure in outpatient setting?

The following PICOTS were used to select literature to inform this review.

Patients

The relevant population of interest is patients with chronic heart failure who are at risk of developing acute decompensated heart failure.

Interventions

The test being considered is thoracic bioimpedance/impedance cardiography.

Bioimpedance is defined as the electrical resistance of current flow through tissue. For example, when small electrical signals are transmitted through the thorax, the current travels along the blood-filled aorta, which is the most conductive area. Changes in bioimpedance, measured during each beat of the heart, are inversely related to pulsatile changes in volume and velocity of blood in the aorta. Cardiac output is the product of stroke volume by heart rate and, thus, can be calculated from bioimpedance. Cardiac output is generally reduced in patients with systolic heart failure. Acute decompensation is characterized by worsening of cardiac output from the patient's baseline status. The technique is alternatively known as impedance cardiography.

Comparators

The comparator of interest is standard clinical care without testing. Decisions regarding to guide volume management are being made based on signs and symptoms.

Outcomes

The general outcomes of interest are prevention of decompensation episodes, reductions in hospitalization and mortality, and improvement in quality of life.

Trials of using thoracic bioimpedance/impedance cardiography in this population were not found. Generally, demonstration of outcomes over a 1-year period is meaningful for interventions.

Simplifying Test Terms

There are 3 core characteristics for assessing a medical test. Whether imaging, laboratory, or other, all medical tests must be:

• Technically reliable

• Clinically valid

• Clinically useful.

Technically Reliable

Assessment of technical reliability focuses on specific tests and operators and requires review of unpublished and often proprietary information. Review of specific tests, operators, and unpublished data are outside the scope of this evidence review and alternative sources exist. This evidence review focuses on the clinical validity and clinical utility.

Clinically Valid

A test must detect the presence or absence of a condition, the risk of developing a condition in the future, or treatment response (beneficial or adverse).

Several studies were excluded from the evaluation of the clinical validity of the thoracic bioimpedance/impedance cardiography test because they did not include information needed to assess clinically validity.

Packer et al (2006) reported on use of impedance cardiography (ICG) measured by BioZ ICG monitor to predict decompensation in patients with chronic heart failure. In this study, 212 stable patients with heart failure and a recent episode of decompensation underwent serial evaluation and blinded ICG testing every 2 weeks for 26 weeks and were followed for the occurrence of death or worsening heart failure requiring hospitalization or emergent care. During the study, 59 patients experienced 104 episodes of decompensated heart failure, including 16 deaths, 78 hospitalizations, and 10 emergency department visits. Results are summarized in Table 10. A composite score of 3 ICG parameters was a predictor of an event during the next 14 days (p<0.001).

Table 10. Clinical Validity of 3-Level Risk Score for BioZ ICG Monitor

Author

Initial N

Final N

Excluded Samples

Prevalence of Condition

Clinical Validity: Mean Probability of Outcome (95% CI), %

Low Risk

Medium Risk

High Risk

Packer et al (2006)

212

212

None

59 patients had 104 episodes of decompensated HF including 16 deaths, 78 hospitalizations, 10 ED visits

1.0 (0.5 to 1.9)

3.5 (2.4 to 4.8)

8.4 (5.8 to 11.6)

CI: confidence interval; ER: emergency department; HF: heart failure.

Section Summary: Clinically Valid

Clinical validity of using thoracic bioimpedance/impedance cardiography for patients with chronic heart failure who are at risk of developing acute decompensated heart failure has not been established. Association studies are insufficient evidence to determine whether thoracic bioimpedance/impedance cardiography can improve outcomes patients with chronic heart failure who are at risk of developing acute decompensated heart failure. There are no studies reporting the clinical validity in terms of sensitivity, specificity, or predictive value.

Clinically Useful

A test is clinically useful if the use of the results informs management decisions that improve the net health outcome of care. The net health outcome can be improved if patients receive correct therapy, or more effective therapy, or avoid unnecessary therapy, or avoid unnecessary testing.

Direct Evidence

Direct evidence of clinical utility is provided by studies that have compared health outcomes for patients managed with and without the test. Because these are intervention studies, the preferred evidence would be from randomized controlled trials.

Amir et al (2017) reported on results of a prospective study in which 59 patients recently hospitalized for heart failure was selected for ReDS-guided treatment for 90 days. The number of heart failure hospitalizations during 90-day ReDS-guided therapy were compared with hospitalizations in the preceding 90 days before enrollment and the 90 days following discontinuation of ReDS monitoring. During treatment, patients were equipped with the ReDS wearable vest, which was worn once a day at home to measure lung fluid content. Study characteristics and results are summarized in Tables 11 and 12. The rate of heart failure hospitalizations was lower during the ReDS-guided follow-up compared with pre and posttreatment periods. Interpretation of results is uncertain due to the lack of concurrent control and randomization, short-term follow-up, large CIs, and lack of clarity about lost-to-follow-up during the post-ReDS period. An RCT comparing ReDS monitoring with standard of care (SMILE; NCT02448342) was initiated but terminated before its completion.

Table 11. Summary of Key Nonrandomized Study Characteristics

Author

Study Type

Country

Dates

Participants

Treatment

Mean FU (SD),d

Amir et al (2017)

Pre-post prospective cohort

Israel

2012-2015

Patients ≥18 y with stage C heart failure, regardless of LVEF (n=59)

ReDS Wearable System

83.0 (25.4)

a Treatment vs pretreatment period. b Treatment vs posttreatment period.

Table 12. Summary of Key Nonrandomized Study Results

Study

HFH (events/patient/3 mo)

Deaths

Amir et al (2017)20

50

50

Pre-90-day period (control)

0.04

NA

90-day treatment period

0.30

2

Post-90-day period (control)

0.19

2

Hazard ratio (95% confidence interval); p

• 0.07 (0.01 to 0.54); 0.01a

• 0.11 (0.014 to 0.88); 0.037b

a Treatment vs pretreatment period. b Treatment vs posttreatment period

Chain of Evidence

Indirect evidence on clinical utility rests on clinical validity. If the evidence is insufficient to demonstrate test performance, no inferences can be made about clinical utility. Because clinical validity of using thoracic bioimpedance/impedance cardiography has not been proven, a chain of evidence to build a case for clinical utility cannot be made.

Section Summary: Clinical Utility

Clinical utility of using thoracic bioimpedance/impedance cardiography for patients with chronic heart failure who are at risk of developing acute decompensated heart failure has not been established. One prospective longitudinal study reported ReDS-guided management reduced heart failure readmissions in acute decompensated heart failure patients recently discharged from the hospital. However, interpretation of results is uncertain due to the lack of concurrent control and randomization, short-term follow-up, large confidence intervals, and lack of clarity about lost-to-follow-up during the post-ReDS period. An RCT comparing ReDS monitoring with standard of care was initiated but terminated prior to its completion.

Inert Gas Rebreathing

Clinical Context and Test Purpose

The purpose of inert gas breathing in patients who have heart failure in an outpatient setting is to (1) guide volume management, (2) identify physiologic changes that precede clinical symptoms and thus allow preventive interventions, and (3) prevent hospitalizations.

The question addressed in this evidence review is does use of inert gas breathing improve health

outcomes in individuals with heart failure in outpatient setting?

The following PICOTS were used to select literature to inform this review.

Patients

The relevant population of interest is patients with chronic heart failure who are at risk of developing acute decompensated heart failure.

Interventions

The test being considered is inert gas breathing.

Inert gas rebreathing is based on the observation that the absorption and disappearance of a blood-soluble gas are proportional to cardiac blood flow. The patient is asked to breathe and rebreathe from a bag filled with oxygen mixed with a fixed proportion of 2 inert gases, typically nitrous oxide and sulfur hexafluoride. The nitrous oxide is soluble in blood and is therefore absorbed during the blood's passage through the lungs at a rate proportional to the blood flow. The sulfur hexafluoride is insoluble in blood and therefore stays in the gas phase and is used to determine the lung volume from which the soluble gas is removed. These gases and carbon dioxide are measured continuously and simultaneously at the mouthpiece.

Comparators

The comparator of interest is standard clinical care without testing. Decisions regarding to guide volume management are being made based on signs and symptoms.

Outcomes

The general outcomes of interest are prevention of decompensation episodes, reduction in hospitalization and mortality and improvement in quality of life.

Timing

Trials of using inert gas breathing in this population were not found. Generally, demonstration of outcomes over a 1-year period is meaningful for interventions.

Setting

Outpatient setting.

Technically Reliable

Assessment of technical reliability focuses on specific tests and operators and requires review of unpublished and often proprietary information. Review of specific tests, operators, and unpublished data are outside the scope of this evidence review and alternative sources exist. This evidence review focuses on the clinical validity and clinical utility.

Clinically Valid

A test must detect the presence or absence of a condition, the risk of developing a condition in the future, or treatment response (beneficial or adverse).

No studies for clinically validity were identified that determined how use of inert gas rebreathing measurements are helpful in detecting the likelihood of decompensation.

Section Summary: Clinically Valid

Clinical validity of using inert gas breathing for patients with chronic heart failure who are at risk of developing acute decompensated heart failure has not been established.

Clinically Useful

A test is clinically useful if the use of the results informs management decisions that improve the net health outcome of care. The net health outcome can be improved if patients receive correct therapy, or more effective therapy, or avoid unnecessary therapy, or avoid unnecessary testing.

Direct Evidence

Direct evidence of clinical utility is provided by studies that have compared health outcomes for patients managed with and without the test. Because these are intervention studies, the preferred evidence would be from randomized controlled trials.

No studies were identified that determined how use of inert gas rebreathing measurements is associated with changes in patient management or evaluated effects on patient outcomes.

Chain of Evidence

Indirect evidence on clinical utility rests on clinical validity. If the evidence is insufficient to demonstrate test performance, no inferences can be made about clinical utility. Because clinical validity of using inert gas breathing has not been proven, an indirect chain of evidence to build a case for clinical utility cannot be made.

Section Summary: Clinically Valid

No studies of clinical utility were identified that determined how use of inert gas breathing measurements in managing heart failure affects patient outcomes. It is unclear how these devices will improve patient outcomes.

Noninvasive left ventricular End Diastolic Pressure Estimation Methods

Clinical Context and Test Purpose

The purpose of noninvasive left ventricular end diastolic pressure estimation methods in patients who have heart failure in an outpatient setting is to (1) guide volume management, (2) identify physiologic changes that precede clinical symptoms and thus allow preventive interventions, and (3) prevent hospitalizations.

The question addressed in this evidence review is does use of noninvasive left ventricular end diastolic pressure estimation methods improve health outcomes in individuals with heart failure in outpatient setting?

The following PICOTS were used to select literature to inform this review.

Patients

The relevant population of interest is patients with chronic heart failure who are at risk of developing acute decompensated heart failure.

Interventions

The test being considered is noninvasive left ventricular end diastolic pressure estimation.

LVEDP is elevated with acute decompensated heart failure. While direct catheter measurement of LVEDP is possible for patients undergoing cardiac catheterization for diagnostic or therapeutic reasons, its invasive nature precludes outpatient use. Noninvasive measurements of LVEDP have been developed based on the observation that arterial pressure during the strain phase of the Valsalva maneuver may directly reflect the LVEDP. Arterial pressure responses during repeated Valsalva maneuvers can be recorded and analyzed to produce values that correlate to the LVEDP.

Comparators

The comparator of interest is standard clinical care without testing. Decisions to guide volume management are being made based on signs and symptoms.

Outcomes

The general outcomes of interest are prevention of decompensation episodes, reduction in hospitalization and mortality, and improvement in quality of life.

Timing

Trials of using noninvasive left ventricular end diastolic pressure estimation methods in this population were not found. Generally, demonstration of outcomes over a 1-year period is meaningful for interventions.

Setting

Outpatient setting.

Technically Reliable

Assessment of technical reliability focuses on specific tests and operators and requires review of unpublished and often proprietary information. Review of specific tests, operators, and unpublished data are outside the scope of this evidence review and alternative sources exist. This evidence review focuses on the clinical validity and clinical utility.

Clinically Valid

A test must detect the presence or absence of a condition, the risk of developing a condition in the future, or treatment response (beneficial or adverse).

Silber et al (2012) reported on finger photoplethysmography during the Valsalva maneuver performed in 33 patients before cardiac catheterization. Left ventricular end-diastolic pressure (LVEDP) was measured via a catheter placed in the left ventricle and used as the reference standard. For identifying LVEDP greater than 15 mm Hg, finger photoplethysmography during Valsalva maneuver was 85% sensitive (95% confidence interval [CI], 54% to 97%) and 80% specific (95% CI, 56% to 93%).

Section Summary: Clinically Valid

One study was identified assessing the use of LVEDP monitoring in this patient population; it reported 85% sensitivity and 80% specificity to detect LVEDP greater than 15 mm Hg.

Clinically Useful

A test is clinically useful if the use of the results informs management decisions that improve the net health outcome of care. The net health outcome can be improved if patients receive correct therapy, or more effective therapy, or avoid unnecessary therapy, or avoid unnecessary testing.

Direct Evidence

Direct evidence of clinical utility is provided by studies that have compared health outcomes for patients managed with and without the test. Because these are intervention studies, the preferred evidence would be from randomized controlled trials.

No studies were identified that determined how use of noninvasive left ventricular end diastolic pressure estimation methods is associated with changes in patient management or evaluated effects on patient outcomes.

Chain of Evidence

Indirect evidence on clinical utility rests on clinical validity. If the evidence is insufficient to demonstrate test performance, no inferences can be made about clinical utility.

Because clinical validity of using noninvasive left ventricular end diastolic pressure estimation has only been demonstrated in a small single study, an chain of evidence to support clinical utility cannot be made.

Section Summary: Clinically Valid

No studies of clinical utility were identified that determined how use of noninvasive left ventricular end diastolic pressure estimation methods in managing heart failure affects patient outcomes. A chain of evidence on the clinical utility of noninvasive left ventricular end diastolic pressure estimation cannot be constructed because it is unclear how these devices will improve patient outcomes.

Summary of Evidence

For individuals who have heart failure in outpatient settings who receive hemodynamic monitoring with an implantable pulmonary artery pressure sensor device, the evidence includes randomized controlled trials (RCTs). Relevant outcomes are overall survival, symptoms, functional outcomes, quality of life, morbid events, hospitalizations, and treatment-related morbidity. One implantable pressure monitor, the CardioMEMS device, has U.S. Food and Drug Administration approval. The pivotal CHAMPION RCT reported a statistically significant decrease in heart failure-related hospitalizations in patients implanted with CardioMEMS device compared with usual care. However, the results were potentially biased in favor of the treatment group due to use of additional nurse communication to enhance protocol compliance with the device. The manufacture conducted multiple analyses to address the issue of potential bias from the nurse interventions. These were reviewed favorably by FDA. While these analyses demonstrated consistency of benefit from the CardioMEMS device, all such analyses have methodologic limitations. Early safety data is suggestive of a higher rate of procedural complications, particularly related to pulmonary artery injury. Given that the intervention is invasive, intended to be used for a highly prevalent condition, in the light of limited safety data, lack of demonstrable mortality benefit and pending questions related to its benefit for reduction in hospitalization, the net benefit remains uncertain. Many of these issues may be clarified from the results of an ongoing postmarketing study that is currently ongoing and proposes to enroll 1200 patients with at least 35% women. The evidence is insufficient to determine the effects of the technology on health outcomes.

For individuals who have heart failure in outpatient setting who receive hemodynamic monitoring by thoracic impedance, with inert gas rebreathing, or of arterial pressure during the Valsalva maneuver, the evidence includes uncontrolled prospective studies and case series. Relevant outcomes are overall survival, symptoms, functional outcomes, quality of life, morbid events, hospitalizations, and treatment-related morbidity. There is a lack of RCT evidence evaluating whether use of these technologies improves health outcomes over standard active management of heart failure patient. The case series have reported physiologic measurement-related outcomes and/or associations between monitoring information and heart failure exacerbations, but do not provide definitive evidence on device efficacy. The evidence is insufficient to determine the effects of the technology on health outcomes.

Practice Guidelines and Positions Statements

American College of Cardiology et al

The 2017 joint guidelines by the American College of Cardiology, American Heart Association, and Heart Failure Society of America on the management of heart failure offered no recommendations for use of ambulatory monitoring devices.

European Society of Cardiology

The European Society of Cardiology guidelines on the diagnosis and treatment of acute and chronic heart failure state the following: “Monitoring of pulmonary artery pressures using a wireless implantable hemodynamic monitoring system (CardioMEMS) may be considered in symptomatic patients with heart failure with previous heart failure hospitalization in order to reduce the risk of recurrent heart failure hospitalization (Class IIb Level B recommendation).”

National Institute for Health and Clinical Excellence

The updated 2018 guidance from the National Institute for Health and Care Excellence (NICE) on chronic heart failure management did not include outpatient hemodynamic monitoring as a recommendation.

In 2013, NICE issued guidance on the insertion and use of implantable pulmonary artery pressure monitors in chronic heart failure. The recommendations concluded that “Current evidence on the safety and efficacy of the insertion and use of implantable pulmonary artery pressure monitors in chronic heart failure is limited in both quality and quantity.”

Heart Failure Society of America

In 2018, the Heart Failure Society of America Scientific Statements Committee published a white paper consensus statement on remote monitoring of patients with heart failure.

The committee concluded that: "Based on available evidence, routine use of external RPM devices is not recommended. Implanted devices that monitor pulmonary arterial pressure and/or other parameters may be beneficial in selected patients or when used in structured programs, but the value of these devices in routine care requires further study.

U.S. Preventive Services Task Force Recommendations

Not applicable

Key Words:

Thoracic electrical bioimpedance, TEB, impedance cardiography, ICD, cardiac output, CO, thermodilution, inert gas rebreathing, BioZ®, Innocor, VeriCor®, Endosure®, Implantable Direct Pulmonary Artery Pressure, Left Ventricular End Diastolic Pressure, LVEDP, Noninvasive Measurement, CardioMEMS, thoracic bioimpedance, TEBCO®, IQ™, Zoe®, Cheetah NICOM®, PhysioFlow®, Cardiography

Approved by Governing Bodies:

Noninvasive Left Ventricular End Diastolic Pressure Measurement Devices

In June 2004, the VeriCor® (CVP Diagnostics, Boston, MA), a noninvasive left ventricular end diastolic pressure measurement device, was cleared for marketing by the U.S. Food and Drug Administration (FDA) through the 510(k) process. FDA determined that this device was substantially equivalent to existing devices for the following indication:

“The VeriCor is indicated for use in estimating non-invasively, left ventricular end-diastolic pressure (LVEDP). This estimate, when used along with clinical signs and symptoms and other patient test results, including weights on a daily basis, can aid the clinician in the selection of further diagnostic tests in the process of reaching a diagnosis and formulating a therapeutic plan when abnormalities of intravascular volume are suspected. The device has been clinically validated in males only. Use of the device in females has not been investigated.”

Thoracic Bioimpedance Devices

Multiple thoracic impedance measurement devices that do not require invasive placement have been cleared for marketing by the U.S. Food and Drug Administration (FDA) 510(k) process.  FDA determined that this device was substantially equivalent to existing devices for use for peripheral blood flow monitoring.  Table 13 includes a representative list of devices, but is not meant to be comprehensive (FDA product code: DSB).

Table 13:  Noninvasive Thoracic Impedance Plethysmography Devices

Device

Manufacturer

Year of FDA Clearance

BioZ ® Thoracic Impedance Plethysmograph

SonoSite (Bothell, WA)

2009

Zoe® Fluid Status Monitor

Noninvasive Medical Technologies LLC (Las Vegas, NV)

2004

Cheetah Starling SV

Cheetah Medical Inc.

2008

Physioflow® Signal Morphology-based Impedance Cardiography (SM-ICG™)

Vasocom Inc., now Neumedx Inc. (Bristol, PA)

2008

ReDS™  Wearable System

Sensible Medical Innovations (Philadelphia, PA)

2015

FDA:  U.S. Food and Drug Administration.

In addition, several manufacturers market thoracic impedance measurement devices that are integrated into implantable devices.

Inert Gas Rebreathing Devices

In March 2006, the Innocor® (Innovision, Denmark), an inert gas rebreathing device, was cleared for marketing by FDA through the 510(k) process. FDA determined that this device was substantially equivalent to existing inert gas rebreathing devices for use in computing blood flow.  FDA product code: BZG.

Implantable Pulmonary Artery Pressure Sensor Devices

In May 2014, the CardioMEMS™ Champion Heart Failure Monitoring System (CardioMEMS, now Abbott) was cleared for marketing by FDA through the premarket approval process. This device consists of an implantable pulmonary artery (PA) sensor, which is implanted in the distal PA, a transvenous delivery system, and an electronic sensor that processes signals from the implantable PA sensor and transmits PA pressure measurements to a secure database. The device originally underwent FDA review in 2011, at which point FDA decided that there was no reasonable assurance that the discussed monitoring system would be effective, particularly in certain subpopulations, although it was agreed that this monitoring system was safe for use in the indicated patient population.

Several other devices that monitor cardiac output by measuring pressure changes in the PA or right ventricular outflow tract have been investigated in the research setting but have not received FDA approval. They include the Chronicle® implantable continuous hemodynamic monitoring device (Medtronic, Minneapolis, MN), which includes a sensor implanted in the right ventricular outflow tract, and the ImPressure® device (Remon Medical Technologies, Caesara, Israel), which includes a sensor implanted in the PA.

Note: This evidence review only addresses use of these techniques in ambulatory care and outpatient settings.

Benefit Application:

Coverage is subject to member’s specific benefits.  Group specific policy will supersede this policy when applicable.

ITS: Home Policy provisions apply

FEP:  Special benefit consideration may apply.  Refer to member’s benefit plan.  FEP does not consider investigational if FDA approved and will be reviewed for medical necessity.

Current Coding: 

CPT Codes:

33289

Transcatheter implantation of wireless pulmonary artery pressure sensor for long-term hemodynamic monitoring, including deployment and calibration of the sensor, right heart catheterization, selective pulmonary catheterization, radiological supervision and interpretation, and pulmonary artery angiography, when performed (Effective 01/01/2019)

93264

Remote monitoring of a wireless pulmonary artery pressure sensor for up to 30 days, including at least weekly downloads of pulmonary artery pressure recordings, interpretation(s), trend analysis, and report(s) by a physician or other qualified health care professional (Effective 01/01/2019)

There is a specific CPT code for bioimpedance:

93701

Bioimpedance-derived physiologic cardiovascular analysis

Inert gas rebreathing measurement and LVEDP should be reported using the unlisted code 93799.

There is no specific CPT code for implantable direct pressure monitoring of the pulmonary artery.  The unlisted code 93799 would be used.

93799

Unlisted cardiovascular service or procedure

References:

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  2. Abraham WT, Adamson PB, Bourge RC et al. Wireless pulmonary artery haemodynamic monitoring in chronic heart failure: a randomised controlled trial. Lancet 2011; 377(9766):658-66.
  3. Abraham WT, Adamson PB, Bourge RC, et al. Wireless pulmonary artery haemodynamic monitoring in chronic heart failure: a randomised controlled trial. Lancet 2011; 377(9766):658-66.
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Policy History:

Medical Policy Group, July 2010 (1)

Medical Policy Administration Committee, July 2010

Available for comment July 23-September 6, 2010

Medical Policy Group, July 2011 (1): Update to Key Points, Approved by Governing Bodies and References

Medical Policy Group, August 2011 (1): Merge policy #363 onto this policy related to non-invasive measurement of LVEDP in outpatient setting and archive policy #363

Medical Policy Administration Committee, August 2011

Medical Policy Group, July 2012 (1): Update to Key Points and References related to MPP update; no change to policy statement

Medical Policy Group, July 2013 (4): 2013 Update to Description, Key Points and References

Medical Policy Panel, July 2014

Medical Policy Group, July 2014 (4): 2014 Update to Description, Approved Governing Bodies, Key Points, Key Words, & References; no change in policy statement

Medical Policy Group, September 2014 (3): October Quarterly Coding Update – added to current coding section code C9741 & description with effective date 10/1/14

Medical Policy Group, November 2014: Annual Coding update.  Added HCPC code C2624 to current coding, effective date01/01/15; also updated C9741 with the removal of “includes provision of patient home electronics unit”.

Medical Policy Panel, July 2015

Medical Policy Group, July 2015(4): Updates to Description, Key Points, Key Words and References.  No change to policy statement.

Medical Policy Panel, May 2016

Medical Policy Group, May 2016 (4): Updates to Description, Key Points and References. No change to policy statement.

Medical Policy Panel, May 2017

Medical Policy Group, June 2017 (4):  Updates to Description, Key Points, Approved by Governing Bodies, Coding and References.  No change to policy statement. Removed Previous CPT coding 0104T and 0105T that were deleted 1/1/11 and removed HCPCs codes C2624 and C9741.

Medical Policy Panel, May 2018

Medical Policy Group, May 2018 (4): Updates to Description, Key Points, Approved by Governing Bodies, and References. No change to policy statement.

Medical Policy Group, December 2018:  2019 Annual Coding Update.  Added CPT codes 33289, 93264 to the Current Coding section.

Medical Policy Panel, May 2019

Medical Policy Group, May 2019 (4): Updates to Description, Key Points, and References.  No change to policy statement.


This medical policy is not an authorization, certification, explanation of benefits, or a contract. Eligibility and benefits are determined on a case-by-case basis according to the terms of the member’s plan in effect as of the date services are rendered. All medical policies are based on (i) research of current medical literature and (ii) review of common medical practices in the treatment and diagnosis of disease as of the date hereof. Physicians and other providers are solely responsible for all aspects of medical care and treatment, including the type, quality, and levels of care and treatment.

This policy is intended to be used for adjudication of claims (including pre-admission certification, pre-determinations, and pre-procedure review) in Blue Cross and Blue Shield’s administration of plan contracts.

The plan does not approve or deny procedures, services, testing, or equipment for our members. Our decisions concern coverage only. The decision of whether or not to have a certain test, treatment or procedure is one made between the physician and his/her patient. The plan administers benefits based on the member’s contract and corporate medical policies. Physicians should always exercise their best medical judgment in providing the care they feel is most appropriate for their patients. Needed care should not be delayed or refused because of a coverage determination.

As a general rule, benefits are payable under health plans only in cases of medical necessity and only if services or supplies are not investigational, provided the customer group contracts have such coverage.

The following Association Technology Evaluation Criteria must be met for a service/supply to be considered for coverage:

1. The technology must have final approval from the appropriate government regulatory bodies;

2. The scientific evidence must permit conclusions concerning the effect of the technology on health outcomes;

3. The technology must improve the net health outcome;

4. The technology must be as beneficial as any established alternatives;

5. The improvement must be attainable outside the investigational setting.

Medical Necessity means that health care services (e.g., procedures, treatments, supplies, devices, equipment, facilities or drugs) that a physician, exercising prudent clinical judgment, would provide to a patient for the purpose of preventing, evaluating, diagnosing or treating an illness, injury or disease or its symptoms, and that are:

1. In accordance with generally accepted standards of medical practice; and

2. Clinically appropriate in terms of type, frequency, extent, site and duration and considered effective for the patient’s illness, injury or disease; and

3. Not primarily for the convenience of the patient, physician or other health care provider; and

4. Not more costly than an alternative service or sequence of services at least as likely to produce equivalent therapeutic or diagnostic results as to the diagnosis or treatment of that patient’s illness, injury or disease.