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How changes to the Medicare Benefits Schedule could improve the practice of cardiology and save taxpayer money

Richard W Harper, Arthur Nasis and Vijaya Sundararajan
Med J Aust 2015; 203 (6): 256-258. || doi: 10.5694/mja15.00333
Published online: 21 September 2015

Summary

  • Rising health care costs above inflation are placing serious strains on the sustainability of the Australian Medicare system in its current structure.
  • The Medicare Benefits Schedule (MBS), which lists rebates payable to patients for private medical services provided on a fee-for-service basis, is the cornerstone of the Australian health care system. Introduced in the 1980s, the MBS has changed little despite major advances in the evidence base for the practice of cardiology.
  • We outline how we believe sensible changes to the MBS listings for four cardiac services — invasive coronary angiography, computed tomography coronary angiography, stress testing and percutaneous coronary intervention — would improve the clinical practice of cardiology and save substantial amounts of taxpayer money.

The Australian Medicare system is a government-funded fee-for-service system that is highly regarded by the general public. A major advantage of the system is that low-income non-insured patients have ready access to approved ambulatory medical services at little or no cost to them, with public inhospital care provided at no charge. However, a disadvantage is the potential for over servicing. This may occur when new technology or new knowledge lessens or eliminates the indications for a test, without such a development being reflected by a change in the criteria for the particular Medicare Benefits Schedule (MBS) item number. In these circumstances, a medical practitioner may disregard advances in the medical evidence base and continue to practice in the same way, particularly if it is financially advantageous to do so. The examples we discuss in this article reflect this phenomenon. Computed tomography coronary angiography (CTCA), a new, safer and much less expensive technology, should replace invasive coronary angiography (ICA) for the diagnosis of coronary artery disease (CAD), but based on Medicare item reports for 2010–2014,1 this is happening only slowly. Measurement of the fractional flow reserve (FFR) clearly improves the practice of percutaneous coronary intervention (PCI) and saves both money and lives; however, the uptake in Australia has been slow.1 A nuclear stress test has a high radiation burden and is 3.4 times more expensive than a stress echocardiogram,2 yet under the current MBS system it can be ordered by any medical practitioner who may or may not be aware of the cost or the radiation risk.

Invasive coronary angiography

ICA is an expensive procedure ($5187–$6289 per procedure; Appendix 1), with substantial cost to the taxpayer (Box 1). It carries a small risk of serious complications and a radiation burden (5–7 mSv).3 It is a guideline-recommended investigation for patients presenting with troponin-positive acute coronary syndrome.4 In these circumstances, ICA and PCI, if necessary, should be performed by an interventional cardiologist at the same sitting.

ICA is also indicated in symptomatic patients with known stable CAD or with a high probability of CAD who have evidence of myocardial ischaemia of sufficient severity to justify revascularisation with PCI or coronary artery bypass grafting.5 In these circumstances, initial ICA is often performed by a non-interventional cardiologist, and a second ICA and a PCI, if indicated, is then carried out by an interventional cardiologist. This practice is inefficient; the patient and the Medicare system will be billed for two ICAs and a PCI, whereas if the initial ICA had been performed by an interventional cardiologist, only one ICA (and one PCI) would have been charged. Further, in most cases, the decision of a non-interventional cardiologist to refer a patient for PCI after the baseline ICA will be made on visual (anatomical) assessment of the coronary lesion(s), whereas it should be guided by both anatomical and functional assessment.6 The diagnostic accuracy of ICA based on diameter stenosis alone to predict functionally significant coronary artery stenosis (ie, lesions causing ischaemia) is poor.7,8 In the FAME (Fractional flow reserve versus Angiography for Multivessel Evaluation) study, 35% and 80% of coronary lesions seen on ICA with diameter stenosis between 50%–70% and 70%–90%, respectively, were functionally significant by FFR measurement.8 The implication of these findings is that if a patient with stable CAD undergoes ICA for the purpose of assessing suitability for revascularisation, the operator should be capable of performing FFR measurement. As FFR measurement involves instrumentation of the coronary artery with a pressure wire, interventional training is required for its safe performance. This lends further support that ICA is best performed by an interventional cardiologist.

ICA is no longer an appropriate test for the diagnosis of CAD, because it is associated with a low rate of obstructive CAD warranting intervention, even when preceded by an abnormal stress test result.9 It accurately examines the lumen of the coronary artery but does not detect non-obstructive atherosclerotic lesions in the coronary wall that could be a nidus for future coronary events.10 That is, a “normal” ICA finding does not always exclude coronary atherosclerosis.

We suggest that the item numbers for ICA should only be payable if the procedure is performed by an accredited interventional cardiologist in a hospital with accredited PCI facilities.

In cardiology, there is already a precedent for a procedural item number to be available only to an accredited cardiologist. For example, the item number for extraction of a permanent pacemaker lead is only available to cardiologists accredited for that procedure on the advice of the Cardiac Society for Australia and New Zealand. To our knowledge, all public and private hospitals performing PCI have an accreditation process to allow cardiologists to carry out the procedure in their hospital. For new applications, accreditation approval in these hospitals requires evidence that the candidate has undergone specialised training in interventional cardiology and is regarded as competent by his or her supervisors. We suggest that all interventional cardiologists currently accredited to perform PCI be allowed to charge the item numbers for ICA, and that new applications for accreditation be vetted by the Cardiac Society for Australia and New Zealand.

Operator compliance with the indications for ICA could be monitored by examination of an individual cardiologist’s Medicare statistics or, alternatively, by a national cardiac procedures registry. For example, if ICA was only being performed in the setting of troponin-positive acute coronary syndrome or for patients with known CAD and objective evidence of ischaemia not sufficiently controlled with medical therapy, one would expect most patients to require a revascularisation procedure such as PCI or coronary artery bypass grafting. On this basis, the ratio of ICA to revascularisation should be at least less than 2.0 : 1 and preferably in the order of 1.5 : 1. If an individual cardiologist’s statistics fall well outside this range (eg, greater than 2 SDs from that of his or her peers), that cardiologist could be asked to justify the discrepancy.

Computed tomography coronary angiography

Compared with ICA, CTCA is a safer, less invasive and less expensive (the cost to the taxpayer is $622 per angiogram) outpatient investigation and carries a lower radiation burden. The costs of equipping and running a CTCA service in terms of equipment and personnel are far less than those for a cardiac catheterisation laboratory. In regional hospitals without cardiac catheterisation and PCI facilities, the presence and appropriate use of CTCA would allow many patients to be treated locally without the need for transfer to larger centres.

CTCA should be considered as a logical first-line investigation in patients with suspected CAD.11-13 There are three possible outcomes to a CTCA investigation. First, the angiogram may show completely normal results. In such a patient, the likelihood of a coronary event occurring within the next 5 years is extremely low.14,15 Second, the angiogram may show non-obstructive coronary atherosclerosis. In this instance, the patient’s symptoms are unlikely to be caused by myocardial ischaemia. Nevertheless, such patients are at increased risk of future cardiovascular events and require lifestyle advice and possibly anti-atherosclerotic therapy.14,16,17 Third, the angiogram may show obstructive intramural coronary atherosclerotic lesions (or non-evaluable segments as a result of heavy calcifications). Symptomatic patients with these lesions require lifelong anti-atherosclerotic therapy and may benefit from a stress test to determine the presence of ischaemia. CTCA alone is of little or no diagnostic value in patients with pre-existing CAD, because with current technology, routine CTCA is not capable of reliably detecting ischaemia.18

We suggest that the item number for CTCA be payable only if performed in patients without known CAD. For patients whose initial CTCA results are normal, a second CTCA investigation should only be rebatable if it is performed at least 5 years after the first. The imposition of these restrictions would undoubtedly reduce over servicing and help stem the dramatic rise in the use of CTCA.

Stress testing

Stress testing (electrocardiogram based, echocardiogram based or nuclear based) is the non-invasive test of choice for detection of myocardial ischaemia but is a less suitable test for the diagnosis of CAD.19 A standard electrocardiogram stress test is less accurate than either a nuclear stress test or a stress echocardiogram to determine the site and extent of ischaemia. A stress echocardiogram and a nuclear stress test have similar sensitivity for detecting ischaemia but the former has a higher specificity.20 Stress echocardiography is not associated with any radiation exposure but may be technically difficult in patients with unfavourable body habitus. On the other hand, a stress nuclear test is 3.4 times more expensive ($756 v $222) and carries an average radiation burden of 9–11 mSv.3 For these reasons, we suggest that the item number for a nuclear stress test be payable only if ordered by a physician and only if a stress echocardiogram is considered unsuitable for technical reasons.

Percutaneous coronary intervention

ICA with a view to PCI at the culprit lesion, if technically suitable, is a guideline recommendation for patients with acute coronary syndrome.4 In stable CAD, the benefit from PCI with optimal medical therapy is less certain compared with medical therapy alone.21 Furthermore, stenting of non-ischaemic coronary lesions leads to higher rates of mortality and myocardial infarction.22 A coronary lesion can be assumed to be causing ischaemia only if there is > 90% stenosis in a major coronary artery or if it is a single lesion in a coronary vessel supplying an area of myocardium identified as ischaemic on stress testing. All other coronary lesions should not be stented in stable CAD unless the FFR is less than 0.8. Use of FFR in this manner has been shown to reduce stent insertions, improve outcomes and lower health costs.23,24 According to Medicare item reports for 2013–2014,1 only 16% of cases of PCI were associated with FFR. The implication of this finding is that, in Australia, many patients must be undergoing PCI procedures that are potentially detrimental to their health.

We suggest separate MBS item numbers for PCI for troponin-positive acute coronary syndrome and for PCI for stable CAD, thus allowing easier evaluation of the Medicare statistics of an individual practitioner. The item number for PCI for stable CAD should only be payable if one of three conditions is satisfied: (i) a stenosis >90% in a coronary vessel >2 mm in diameter; (ii) a single lesion in a vessel supplying an area of myocardium identified as ischaemic on stress testing; or (iii) a coronary lesion associated with an FFR less than 0.8.

Overall savings resulting from our proposed changes

The overall savings resulting from these changes are summarised in Box 2. Medicare statistics along with data from the Australian Commission on Safety and Quality in Health Care25 were used to calculate the ratio of ICA to revascularisation and the cost to the taxpayer of unnecessary ICA (defined as in excess of a ratio of 1.5 : 1; Appendix 2). Applying this ratio to the four patient groups discussed, taxpayers could have saved $233.5 million and private health insurance companies $139.8 million in 2013–2014.

If our suggested changes to PCI were to occur, the annual savings to the Australian health budget would be in the order of $4 million.24 Changes for CTCA would be cost neutral in the short term but would save costs in the long term (Appendix 2).

In 2013–2014, 77 564 nuclear stress tests were charged to Medicare (cost per test, $756). It is likely that at least 75% of these patients could have had a less expensive stress echocardiogram (cost per test, $222) as an alternative. Doing so would have saved over $30 million of the Medicare budget.

We believe that these relatively simple changes to the MBS would improve the practice of cardiology (Box 3) and result in substantial savings to the health budget (Box 2). Undoubtedly, some cardiologists will consider the suggested changes to be an unwelcome interference with their practice. The counter argument is that as funders of Medicare, the government has a right and a duty to spend public money prudently.

In 2013–2014, the ratio of ICA to revascularisation was substantially higher in the private compared with the public system (3.1 v 2.3; Appendix 2). The likely explanation relates to the effect of fee-for-service on the provision of ICA.

A potential disadvantage of performing PCI at the same sitting as the initial ICA is that the patient will be denied the opportunity for surgical consultation. However, in light of recent evidence indicating the clear superiority of coronary artery bypass grafting over PCI for patients with complex multivessel disease or with diabetes with multivessel disease,26,27 we believe the need for multidisciplinary discussion to determine the best revascularisation option will be infrequent. We consider our recommended ratio of ICA to revascularisation of 1.5 : 1 or less to be sufficiently elastic to accommodate this possibility without compromising patient care.

In summary, we believe these relatively simple changes to the MBS would result in improved evidence-based cardiology practice and substantial savings to the health budget in an ever-increasingly constrained fiscal climate.

1  Cost to the taxpayer of unnecessary invasive coronary angiography (ICA), 2013–2014

ICA to revascularisation ratio

No. of unnecessary cases

Cost per unnecessary case

Cost per year


Public inpatient

2.3 : 1

23 060

$5773

$133.13m

Private in public

2.7 : 1

2986

$4964

$14.82m

Private inpatient

3.1 : 1

38 259

$2199

$84.13m

Non-insured outpatient

2.4 : 1

1871

$759

$1.42m

Total cost

$233.5m



2  How much money could be saved?

Measure

Potential annual savings


Reducing invasive coronary angiography to revascularisation ratio to 1.5 : 1

$233.5m

Limitations to computed tomography coronary angiography

Cost neutral

Reducing nuclear stress tests

$30.1m

More use of fractional flow reserve

$4.0m

Total

$267.6m



3  How our proposed changes to the Medicare Benefits Schedule could improve cardiology practice

  • More judicious use of invasive coronary angiography = less complications, less radiation exposure, less waste of catheter laboratory resources.
  • More judicious use of computed tomography coronary angiography = earlier diagnosis of coronary artery disease, better prognostic assessment, lifestyle modifications and medical therapy where appropriate.
  • More judicious use of nuclear stress test = less radiation burden.
  • Greater use of fractional flow reserve-guided percutaneous coronary intervention = less inappropriate percutaneous coronary intervention and less myocardial infarction and death.

Provenance: Not commissioned; externally peer reviewed.

  • Richard W Harper1
  • Arthur Nasis1
  • Vijaya Sundararajan2

  • 1 Monash Health, Melbourne, VIC
  • 2 University of Melbourne, Melbourne, VIC


Competing interests:

No relevant disclosures.

  • 1. Australian Government Department of Human Services. Medicare Australia Statistics. Medicare item reports. http://medicarestatistics.humanservices.gov.au/statistics/mbs_item.jsp (accessed Mar 2015).
  • 2. Australian Government Department of Health. Medicare Benefits Schedule Online. http://www.mbsonline.gov.au/internet/mbsonline/publishing.nsf/Content/downloads (accessed Aug 2015).
  • 3. Einstein AJ. Radiation risk from coronary artery disease imaging: how do different diagnostic tests compare? Heart 2008; 94: 1519-1521.
  • 4. Aroney CA, Aylward P, Kelly A, et al. National Heart Foundation of Australia and Cardiac Society of Australia and New Zealand guidelines for the management of acute coronary syndromes. Med J Aust 2006; 184 (8 Suppl): S1-S30.
  • 5. Fihn SD, Blankenship JC, Alexander KP, et al. 2014 ACC/AHA/AATS/PCNA/SCAI/STS focused update of the guideline for the diagnosis and management of patients with stable ischemic heart disease. J Am Coll Cardiol 2014; 64: 1929-1949.
  • 6. Pijls NH, De Bruyne B, Peels K, et al. Measurement of fractional flow reserve to assess the functional severity of coronary-artery stenoses. N Engl J Med 1996; 334: 1703-1708.
  • 7. Park SJ, Kang SJ, Ahn JM, et al. Visual-functional mismatch between coronary angiography and fractional flow reserve. JACC Cardiovasc Interv 2012; 5: 1029-1036.
  • 8. Tonino PAL, Fearon WF, De Bruyne B, et al. Angiographic versus functional severity of coronary artery stenoses in the FAME study. J Am Coll Cardiol 2010; 55: 2816-2821.
  • 9. Patel MR, Peterson ED, Dai D, et al. Low diagnostic yield of elective coronary angiography. N Engl J Med 2010; 362: 886-895.
  • 10. Naghavi M, Falk E, Hecht HS, et al. From vulnerable plaque to vulnerable patient, III: Executive summary of the Screening for Heart Attack Prevention and Education (SHAPE) Task Force report. Am J Cardiol 2006; 98: 2H-15H.
  • 11. Harper RW, Ko BS. A new algorithm for the management of stable coronary artery disease incorporating CT coronary angiography and fractional flow reserve: how we can improve outcomes and reduce costs. Med J Aust 2011; 194: 186-189. <MJA full text>
  • 12. Douglas PS, Hoffmann U, Patel MR, et al. Outcomes of anatomical versus functional testing for coronary artery disease. N Engl J Med 2015; 372: 1291-1300.
  • 13. SCOT-HEART investigators. CT coronary angiography in patients with suspected angina due to coronary heart disease (SCOT-HEART): an open-label, parallel-group, multicentre trial. Lancet 2015; 385: 2383-2391.
  • 14. Min JK, Dunning A, Lin FY, et al. Age- and sex-related differences in all-cause mortality risk based on coronary computed tomography angiography findings results from the International Multicenter CONFIRM (Coronary CT Angiography Evaluation for Clinical Outcomes: An International Multicenter Registry) of 23,854 patients without known coronary artery disease. J Am Coll Cardiol 2011; 58: 849-860.
  • 15. Andreini D, Pontone G, Mushtaq S, et al. A long-term prognostic value of coronary CT angiography in suspected coronary artery disease. JACC Cardiovasc Imaging 2012; 5: 690-701.
  • 16. Maddox TM, Stanislawski MA, Grunwald GK, et al. Nonobstructive coronary artery disease and risk of myocardial infarction. JAMA 2014; 312: 1754-1763.
  • 17. Russo V, Zavalloni A, Reggiani M, et al. Incremental Prognostic Value of Coronary CT Angiography in Patients With Suspected Coronary Artery Disease. Circ Cardiovasc Imaging 2010; 3: 351-359.
  • 18. Blankstein R, Di Carli MF. Integration of coronary anatomy and myocardial perfusion imaging. Nat Rev Cardiol 2010; 7: 226-236.
  • 19. Chinnaiyan KM, Raff GL, Goraya T, et al. Coronary computed tomography angiography after stress testing: results from a multicenter, statewide registry, ACIC (Advanced Cardiovascular Imaging Consortium). J Am Coll Cardiol 2012; 58: 849-860.
  • 20. Fleischmann KE, Hunink MG, Kuntz KM, et al. Exercise echocardiography or exercise SPECT imaging? A meta-analysis of diagnostic test performance. JAMA 1998; 280: 913-920.
  • 21. Boden WE, O’Rourke RA, Teo KK, et al. Optimal medical therapy with or without PCI for stable coronary disease. N Engl J Med 2007; 356: 1503-1516.
  • 22. Tonino PA, De Bruyne B, Pijls NH, et al. Fractional flow reserve versus angiography for guiding percutaneous coronary intervention. N Engl J Med 2009; 360: 213-224.
  • 23. Fearon WF, Bornschein B, Pim AL, et al. Economic evaluation of fractional flow reserve-guided percutaneous coronary intervention in patients with multivessel disease. Circulation 2010; 122: 2545-2550.
  • 24. Siebert U, Arvandi M, Gothe RM, et al. Improving the quality of percutaneous revascularisation in patients with multivessel disease in Australia: cost-effectiveness, public health implications, and budget impact of FFR-guided PCI. Heart Lung Circ 2014; 23: 527-533.
  • 25. Australian Commission on Safety and Quality in Health Care; Australian Institute of Health and Welfare. Exploring healthcare variation in Australia: analysis resulting from an OECD study. Sydney: ACSQHC, 2014. http://www.safetyandquality.gov.au/publications/exploring-healthcare-variation-in-australia (accessed Mar 2015).
  • 26. Farkouh ME, Domanski M, Sleepr LA, et al. Strategies for multivessel revascularization in patients with diabetes. N Engl J Med 2012; 367: 2375-2384.
  • 27. Bangalore S, Guo Y, Samadashvili Z, et al. Everolimus-eluting stents or bypass surgery for multivessel coronary disease. N Engl J Med 2015; 372: 1204-1212.

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access_time 11:05, 23 September 2015
Melissa Doohan

Whilst supporting the premise of trying to reduce unnecessary invasive testing, interventional procedures, radiation exposure and costs I suggest it may be necessary to factor in potential differences in patient populations.
For example, many women with ischaemic symptoms, even those with positive non-invasive imaging, or with more acute symptoms and positive ischaemic markers, have non-obstructive coronary disease on formal coronary angiography. This finding should not be interpreted as indicating a non-coronary diagnosis. It often signifies a contribution from endothelial dysfunction or microvascular pathology, or in other cases, may be due to Tako-Tsubo Cardiomyopathy. In such a population a lower percentage of interventions based on FFR might be expected and it may be very reasonable, depending on circumstances, to expect access to repeat subsidised CT coronary angiography within a narrower time frame than 5 years.

Competing Interests: No relevant disclosures

Dr Melissa Doohan
North Shore Private and Sydney Adventist Hospitals

access_time 06:38, 30 September 2015
William Wang

1. The authors note that the fee-for-service system may lead to over servicing, yet they argue that only interventional cardiologists (ie people who benefit financially from interventions) should perform diagnostic angiograms.

We can agree that if a patient has an angiogram performed by a non-interventionist and then referred to an interventionist, the total cost to the health system would be higher for that case. However, only a minority of diagnostic angiograms result in coronary angioplasty. We do not know how more many patients with stable angina would receive angioplasty if the angiogram was performed by an interventionist but would stay on medical therapy only if the angiogram was performed by a non-interventionist. The use of interventional ratios could help monitor over servicing of individuals but not the group.

2. CTCA vs stress echo
CTCA: $622, radiation, issues with contrast.
Stress echocardiography: $222, no radiation, no contrast.

In addition to excluding ischaemia at lower cost and lower risk, stress echocardiography provides additional information on cardiac structures, haemodynamic response with exercise and exercise capacity. It should be the first-line investigation in patients with suspected CAD, as it is in practice already.

Competing Interests: No relevant disclosures

Assoc Prof William Wang
Princess Alexandra Hospital, Brisbane

access_time 10:31, 30 September 2015
Dinesh Sivaratnam

We would make the following observations regarding the article by Rick Harper et al:

Radiation Exposure: While the total dose each procedure imparts on the patient is important, attention also has to be paid to the dose rate (1).
While a CT coronary angiogram (CTCA) could be performed with as little as 3mSv and a myocardial perfusion study (MPS) as high as11mSv, the dose rate from the CTCA could be 5000 times higher that of the MPS. The radiobiology of lower dose rates is thought more favorable than the total dose (1).

Sensitivity of non-invasive testing: MPS is more sensitive in detecting myocardial ischemia than stress echocardiography (SE). This has been demonstrated in large meta-analysis (2).

Access to Nuclear Cardiology: The authors state that a MPS should be ordered only by a physician. Does that mean that the large number of patients who are over weight and whose body habitus precludes them from having a SE should be referred to a physician in order to access such a referral?
It is more likely than not these patients’ will end up having a non diagnostic SE and will then go onto a MPS. Not to mention the implied discrimination of patients with such body habitus not being able to be rapidly evaluated by their general practitioner.

Cost effectiveness of Nuclear Cardiology: Cost effective assessment (CEA) for MPS has been well documented as being favorable and the use of MPS leads to fewer unnecessary revascularization than direct angiography or CTCA as first line investigation (3). In addition in intermediate to high-risk patients the CEA for MPS was superior to SE (4).


References:
1. A.L.Brookes, L.T Dauer. Advances in Radiation Biology:Effect on Nuclear Medicine. Seminars in Nuclear Medicine (2014). Vol 44. Issue 3.179-186.
2.A.F.L Schinkel, J.J Bax, E.Boersma et al. European Heart Journal (2003) 24, 789-800.
3.L.J.Shaw, J Narula. Journal of Nuclear Medicine (2009). Vol 50;No8,1296-1306
4.L.J.Shaw, Marwick TH,Berman DS et al. Incremental cost effectiveness of exercise echocardiography versus SPECT imaging for evaluation of stable chest pain. Eur.Heart.J. 2006;27:2448-2458.

Competing Interests: No relevant disclosures

Dr Dinesh Sivaratnam
The Royal Melbourne Hopital and Cabrini Hospital

access_time 05:51, 21 October 2015
Richard W Harper

We thank Dr. Doohan for her comments.

Potential differences in patient populations: whilst we agree that care is ideally tailored for specific patient needs, we consider our recommendations to hold for the initial evaluation of stable symptoms in all patient groups. The combination of CT coronary angiography (CTCA) and stress echocardiography (SE) provide both anatomic, physiologic and risk stratification information and can be used to make a decision regarding whether the patient warrants invasive angiography (IA).

Regarding women with positive ischaemic markers: our recommendations are for stable symptoms. For patients with symptoms of potential acute myocardial infarction, the Cardiac Society of Australia New Zealand Guidelines recommend IA. Whether these patients require repeated non-invasive testing is beyond the scope of our recommendations.

Competing Interests: No relevant disclosures

Prof Richard W Harper
Monash Health

access_time 05:53, 21 October 2015
Richard W Harper

We thank Dr Wang for his comments.

We agree that currently in Australia only a minority of “diagnostic” IA lead to a revascularisation. As was the main point of our paper we consider this to be a great waste of resources since a diagnosis of coronary artery disease (CAD) can be made much more cheaply and more accurately (since it examines both the wall and lumen of the artery) by CTCA (cost $622) than by IA (cost ~$5000). In stable patients a CTCA should only lead to an IA if the CTCA shows evidence of significant obstructive CAD and the patient has evidence of significant myocardial ischaemia (e.g. classic symptoms, positive functional test) despite optimal medical therapy. If such a policy were followed and the IA was only performed by an interventional cardiologist it is likely that a revascularisation procedure would follow (either an FFR guided percutaneous coronary intervention or referral for coronary artery bypass surgery). The result of such a policy would be the elimination of “diagnostic IA” and the savings of millions of dollars to the health system.

We entirely agree that a stress echo provides valuable anatomic and physiologic information including the presence or absence of ischaemia at a low cost but unlike a CTCA a negative stress echo does not exclude non obstructive CAD that may benefit from optimal anti-atherosclerotic measures.

Competing Interests: No relevant disclosures

Prof Richard W Harper
Monash Health

access_time 06:04, 21 October 2015
Richard W Harper

We thank Drs Sivararatnam and Lichtenstein for their comments.

Radiation Exposure: We accept that dose rate is important, however CTCA provides anatomic data about the coronary circulation whereas myocardial perfusion study (MPS) provides physiologic data: the two tests aren’t comparable. The more valid comparison is with SE which carries no radiation.

Sensitivity of non-invasive testing: The study quoted showed a marginal benefit in sensitivity of MPS over SE (84% vs 80%), although other studies show similar sensitivity (1). It is also widely accepted that SE is more specific than MPS. Putting these subtle differences aside, in our opinion, the 3.4x greater expense of MPS compared to SE and the associated radiation burden of MPS do not justify its current unrestricted widespread use.

Access to Nuclear Cardiology: We don’t accept that overweight patients are “more likely than not” to “end up having a non-diagnostic SE”. In our experience almost all overweight people can undergo SE (exercise or dobutamine) with diagnostic image quality. In fact, we published a paper evaluating 322 patients who underwent SE: the mean body mass index of participants was 29.5±6 and all studies were of diagnostic quality (2).

Cost effectiveness of Nuclear Cardiology: As a first-line investigation comparison should be with functional testing like SE, not CTCA or IA. The quoted study of Shaw and Narula is not relevant to the Australian context because in that study, unlike Australia, the costs of the two investigations were similar.

References:
1. Fleischmann KE, Hunink MG, Kuntz KM, et al. Exercise echocardiography or exercise SPECT imaging? A meta-analysis of diagnostic test performance. JAMA 1998; 280:913-920.
2. Nasis A, Moir S, Meredith IT, et al. Abnormal Left Ventricular Contractile Response to Exercise in the Absence of Obstructive Coronary Artery Disease Is Associated with Resting Left Ventricular Long-Axis Dysfunction. J Am Soc Echocardiogr 2015; 28:95-105.

Competing Interests: No relevant disclosures

Prof Richard W Harper
Monash Health

access_time 08:57, 7 November 2015
William Macdonald

While it is worthy to consider cost reduction and patient safety there are a variety of ways to appropriately assess patients with chest pain. We are concerned with suggestions made by Harper et al1, particularly regarding the role of nuclear cardiology (NC) in the assessment of suspected coronary disease. A large body of evidence has established the gatekeeper role of NC in this setting and studies have shown that NC has greater sensitivity (but less specificity) than stress echocardiography (SE). Indeed, a normal NC scan in a previously well patient can predict a low (< 1%) annual cardiac event rate over many years2,3. Moreover, the ability of NC to quantify extent and severity of ischaemia allows appropriate triage of downstream management, with a demonstrated significant reduction in costs; mildly abnormal studies can appropriately guide the clinician to medical management, avoiding angiography without compromising patient outcomes3. Furthermore, certain patient subgroups may be best assessed by NC (e.g. LBBB, prior infarction, obesity). Additionally, the recent PROMISE trial showed similar outcomes for functional imaging or CTCA4, allowing clinicians an appropriate choice.

We contend that it is completely appropriate for both GPs and specialists to refer patients for NC and SE in the appropriate clinical setting. Decision support tools that assist doctors in choosing the appropriate cardiac investigation are readily available5. The choice will vary with the doctor, the patient and the locally available facilities.

1. Harper RW, Nasis A, Sundararajan V. How changes to the Medicare Benefits Schedule could improve the practice of cardiology and save taxpayer money. Med J Aust 2015; 203: 256-8
2. Schinkel AFL, Boiten HJ, van der Sijde JN, et al. Prediction of 9-year cardiovascular outcomes by myocardial perfusion imaging in patients with normal exercise electrocardiographic testing. Eur Heart J – Cardiovasc Imaging 2012; 13: 900-4
3. Shaw LJ, Narula J. Risk assessment and predictive value of coronary artery disease testing. J Nucl Med 2009; 50: 1296-1306
4. Douglas PS, Hoffman U, Patel MR, et al. Outcomes of anatomical versus functional testing for coronary artery disease. N Engl J Med 2015; 372: 1291-300
5. Wolk MJ, Bailey SR, Doherty JU, et al. ACCF/AHA/ASE/ASNC/HFSA/HRS/SCAI/SCCT/SCMR/STS 2013 multimodality appropriate use criteria for the detection and risk assessment of stable ischemic heart disease: a report of the American College of Cardiology Foundation Appropriate Use Criteria Task Force, American Heart Association, American Society of Echocardiography, American Society of Nuclear Cardiology, Heart Failure Society of America, Heart Rhythm Society, Society for Cardiovascular Angiography and Interventions, Society of Cardiovascular Computed Tomography, Society for Cardiovascular Magnetic Resonance, and Society of Thoracic Surgeons. J Am Coll Cardiol 2014; 63: 380-406

Competing Interests: No relevant disclosures

Dr William Macdonald
President, Australasian Association of Nuclear Medicine Specialists. Head of Nuclear Medicine, Fiona Stanley and Royal Perth Hospitals

access_time 10:01, 11 November 2015
Richard W Harper

We thank Drs Macdonald, Better and MacIsaac for their comments.

We accept that nuclear cardiology has played a useful gatekeeper role in the past but things change. In these times of financial constraint and concerns about patient exposure to radiation we believe it unwise to allow unfettered access to an expensive test which is no more accurate in the detection of ischaemia and provides less structural information about the state of the heart but costs the taxpayer 3.4 times as much as the comparator (stress echocardiography) which carries no radiation burden.

Competing Interests: No relevant disclosures

Prof Richard W Harper
Monash Health

Responses are now closed for this article.