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Can we improve the detection of heart valve disease?
  1. Chris Arden1,
  2. John B Chambers2,
  3. Jonathan Sandoe3,
  4. Simon Ray4,
  5. Bernard Prendergast4,
  6. David Taggart5,
  7. Stephen Westaby5,
  8. Lucy Grothier6,
  9. Jo Wilson7,
  10. Brian Campbell8,
  11. Christa Gohlke-Bärwolf9,
  12. Carlos A Mestres10,
  13. Raphael Rosenhek11,
  14. Philippe Pibarot12,
  15. Catherine M Otto13
  1. 1Royal College of General Practitioners
  2. 2British Heart Valve Society
  3. 3British Infection Association
  4. 4British Cardiovascular Society
  5. 5Society of Cardiothoracic Surgeons of Great Britain and Ireland
  6. 6Director South London Stroke and Cardiovascular Network
  7. 7British Assoc of Nursing for Cardiac Care
  8. 8Society for Cardiological Science and Technology
  9. 9Herz-Zentrum Bad Krozingen, Germany
  10. 10Department of Cardiovascular Surgery, Hospital Clinico, University of Barcelona, Spain
  11. 11University of Vienna, Austria
  12. 12Department of Medicine, Laval University, Canada
  13. 13University of Washington, USA
  1. Correspondence to Professor J B Chambers, Cardiothoracic Centre, St Thomas’ Hospital, London SE1 7EH, UK; john.chambers{at}gstt.nhs.uk

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Introduction

The clinical care of patients with valve disease is best organised by multidisciplinary specialist valve teams.1 ,2 These supervise inpatient and outpatient care, design protocols and processes and coordinate training and education. However, valve disease may not be detected or, if detected, a referral to a specialist team may not be made. This leads to preventable premature death.3 ,4

A working group was therefore convened by the British Heart Valve Society with representatives of all interested national bodies and a panel of invited international commentators. The overall aim was to produce recommendations to improve the detection, conservative management and interventional treatment of valve disease. This document focuses on the detection of valve disease. This occurs principally, but not exclusively, in the community.

Limitations in current detection rates

In the USA, the estimated prevalence of moderate or severe valve disease is 2.5% using population screening.3 By contrast, it was only 1.8% in a separate population when echocardiography was performed according to clinical indications.3 Although the two populations were different geographically and racially, this difference still points to clinically and statistically significant underdetection of valve disease. Similarly, there is major variation between observed and expected rates of aortic valve replacement in the UK5 which is likely to be as a result of differences in rates of detection and referral by general practitioners.

Early detection of asymptomatic moderate or severe disease allows planned surveillance and optimal timing of surgery. By contrast, the EuroHeart survey6 found that approximately 50% of all patients having surgery for valve disease were in NYHA class III or IV which unnecessarily increases morbidity and mortality. Just under a third of patients with heart failure have valve disease7 and heart failure complicated 25% of admissions with aortic valve disease in Scotland between 1997 and 2005.4

At least a third of elderly patients with severe aortic stenosis are not referred for surgery at all even when clinically indicated.8 ,9 Developing a transcatheter valve programme led to increased rates of conventional surgery suggesting the prior existence of clinically inappropriate perceptual barriers to referral.10

Aortic stenosis is commonly diagnosed postmortem11 and undiagnosed aortic stenosis remains an important cause of unexpected perioperative and traumatic death.12 ,13 It is found in 8% of patients admitted acutely requiring surgery for a hip fracture.14

Recommendations

Screening

Although still an essential part of the clinical examination, auscultation has limited sensitivity for valve disease15 particularly when performed by generalists.16 Echocardiography is known to maximise detection3 ,17 but for population screening has rarely been deployed beyond local research projects.

Echocardiography is indicated for patients with murmurs or cardiac symptoms presenting with acute medical or surgical illnesses or electively at preadmission clinics.12 ,14

Population screening for valve disease similar to US research surveys1 would involve major resources and may not be appropriate economically, medically or because of the real risks of medicalising normal people.18 ,19 However, echocardiography is not yet fully used for groups known to be at the highest risk of valve disease20 including those with a murmur or a potential cardiac symptom (box 1). First degree relatives of probands with bicuspid aortic valves have approximately a 10% chance of aortic valve or aortic pathology21 and should also be offered screening.22 Patients who have lived during childhood and adolescence in countries with a high population prevalence of rheumatic disease23 could also be offered screening particularly before non-cardiac surgery or during pregnancy.

Box 1

Indications for community echocardiography*

Established indications20

  • Cardiac symptoms (exertional breathlessness, chest pain, syncope, unexplained decrease in exercise tolerance)

  • Atrial fibrillation without previous echocardiography

  • Abnormal resting 12-lead ECG

  • Clinically obvious systolic murmur†

  • Any diastolic murmur

  • Relative of patients with bicuspid aortic valve21 ,22

Additional indications

  • Patients from areas with a high population prevalence of rheumatic disease17 ,23

  • Age over 75 years, particularly in patients with risk factors, for example, hypertension, diabetes, obesity, hypercholesterolaemia, renal disease or coronary artery disease3 ,24 ,25 ,26

*A comprehensive service including standard echocardiography is necessary, but faster triage could be performed with an initial focused study as has been shown to be cost-effective in suspected heart failure.27

†A trivial short systolic murmur with well-heard second sound should not require echocardiography, but general practitioners may lack the experience to distinguish reliably between a physiological and pathological systolic murmur underlining the potential usefulness of a ‘quick scan’ as an extension of the clinical examination.

We further propose piloting screening echocardiography in those aged over 75 years since they have a 13% chance of moderate or severe valve disease.3 This threshold is supported by European data.24 ,25 It is likely that a particularly high risk subgroup can be defined by the presence of risk factors like hypertension, diabetes, obesity, hypercholesterolaemia, renal disease or coronary artery disease.26 Studies in progress including OxValve may offer insights into the feasibility and appropriateness of this approach.

Within the community, chronic disease annual review clinics provide an opportunity for screening to be organised. Both doctors and practice nurses should be trained and encouraged to perform auscultation as a routine part of their review. In the UK, this might need to be included as part of the Quality and Outcomes Framework, as are other elements of the clinical review which are also of prognostic significance, for example, blood pressure.

Delivery of echocardiography

The method of achieving echocardiography for the community will depend on local arrangements. Examples include:

  1. Hospital or polyclinic-based open access echocardiography service. The diagnostic yield is about 50% for patients with a murmur in the UK (unpublished data). Quality standards for open access services in the UK have been defined.28

  2. Murmur clinic. A focused clinic based in the hospital or community can offer a protocol-driven clinical response to the echocardiogram making it superior to an open access service. These clinics can be led by a cardiologist or, in countries with the necessary training and clinical organisation, by a senior sonographer1 or general practitioner with specialist cardiovascular competencies (including British Society of Echocardiography or European Association of Echocardiography or similar accreditation in echocardiography).

  3. Initial ‘quick scanning’ (box 2) could be performed in the community practice using a portable or hand-held system. There is evidence for the value of hand-held devices29 ,30 and training systems already existing for devolved basic echocardiography.31 It is vital that these are recognised as an extension of the clinical examination and not equivalent to a standard echocardiogram. An abnormal ‘quick scan’ would necessitate a standard echocardiogram on a high-end machine usually based at a hospital. Such a service should be an integral part of a comprehensive echocardiography service in order to maintain quality (box 3). Quality standards have already been defined for the UK.1 ,32

Box 2

Quick scan’* for community screening for valve disease when full echocardiograms are not easily available29,30,31

  • Parasternal long axis view (2D and colour Doppler)

  • Parasternal short axis view of aortic valve, mitral valve (2D and colour Doppler) and mid-left ventricular level

  • Apical 4-chamber, 2-chamber and long axis views (with and without colour Doppler)

  • Subcostal view (for pericardial effusion and engorged inferior vena cava)

*There is no agreed standard terminology. ‘Basic’, ‘limited’, or ‘focused’ echocardiogram or ‘ultrasonic stethoscopy’ have all been used. We propose ‘quick scan’ since it underlines that this is an extension of the clinical examination rather than a substitute for standard echocardiography. The ‘quick scan’ can also be used to rule out significant pathology in many acute presentations in the emergency department or on general medical wards. Spectral Doppler is not included which makes a ‘quick scan’ feasible with hand-held devices and underlines that it cannot substitute for a standard echocardiogram.

Box 3

Properties of community echocardiography for valve disease

  • Availability of echocardiography within 2 weeks for patients with chronic cardiac symptoms*

  • Availability of echocardiography within 1 month for patients with an asymptomatic murmur†

  • Automatic referral of patients found to have moderate or severe valve disease to a valve clinic

  • Links with a cardiothoracic centre in a hub and spoke arrangement either via a specialist valve clinic at a local hospital or run by a general practitioner with specialist cardiovascular interests

  • Provision for structured surveillance of patients with mild native disease or normally-functioning replacement valves

  • Shared archiving between community and hospital

  • Training of general practitioners and education of patients

  • Community echocardiography by accredited operators within high-quality accredited departments including quality assurance, expert back-up and clinical links

*Processes for urgent or emergency assessment of patients with acute or severe symptoms must exist.

†Although not clinically urgent, there is evidence that waiting too long for echocardiography induces anxiety which is not then dispelled by a normal echocardiogram.18

Organisation of echocardiography

Some general practitioners may be uncertain how to interpret the results of an echocardiogram and so it is vital that diagnostic echocardiography occurs within a comprehensive clinical framework. The clinical lead for valve disease in the area, either based at the local hospital or a general practitioner with a special interest in cardiovascular and valve disease, should ensure that echocardiography leads to:

  1. referral of patients found to have moderate or severe valve disease to a specialist valve clinic

  2. appropriate surveillance of patients with mild disease, for example, return to community-based clinic, call-back for serial open access studies

  3. appropriate referral back to the general practitioner of patients with normal echocardiograms to ensure exclusion of other diseases, for example, angina and chronic lung disease.

Studies performed in the community need to be available for review at the local hospital to avoid the need of repeating studies. This can be done in a variety of ways, most conveniently cloud archiving or dedicated secure IT links between community clinics and specialist centres. Encrypted memory sticks or CDs remain in use but are not encouraged.

Detection also occurs in non-cardiac departments within hospitals including emergency departments, general medical and elderly care clinics, stroke units and surgical preadmission and obstetrics clinics. It is important that clinical referral pathways exist once significant valve disease is identified from the clinical examination and echocardiography report. These are the responsibility of the cardiologist running the specialist valve clinic.1

Education and training

There need to be local, national and international educational programmes to encourage general practitioners and hospital based non-cardiologists to refer patients with possible valve disease to specialist valve clinics.1 ,2 Nurses and physicians running preadmission clinics and admitting elderly patients with acute surgical and medical conditions must be aware of how frequent valve disease is in these patients.

There should be provision for general practitioners with experience in cardiovascular medicine to obtain accreditation in echocardiography to undertake initial investigations within the community. It is important that they work in close partnership with local specialist hospital teams to provide clinical governance and immediate clinical back-up as required.

Expert software as currently available for guiding the management of COPD33 should be considered for valve disease. The aim would be to encapsulate national and international guidelines to guide aspects of care including the frequency of echocardiography or the need to refer to a valve clinic as a result of an open access echocardiogram.

There needs to be basic information for patients about valve disease, including the need for dental surveillance to prevent infective endocarditis and the options available for treatment of valve disease. Information currently available about the significance of a murmur is patchy and sometimes misleading.34

Conclusions

Valve disease is increasingly common as our populations age. It may still remain undetected until severe symptoms or acute cardiac decompensation develops. Early detection allows appropriate timing of intervention and is expected to save lives.1 Echocardiography is superior to clinical examination and should be offered to those with high risk features including symptoms or a murmur. Wider screening of the elderly particularly those with atherogenic risk factors should be explored. Community echocardiography must only be performed to the highest standard and must be embedded in a comprehensive diagnostic and clinical service.

References

View Abstract

Footnotes

  • Contributors JBC and CA wrote the first draft and all other coauthors contributed significantly to the final version.

  • Competing interests None.

  • Provenance and peer review Not commissioned; internally peer reviewed.

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