Open access echocardiography (OAE) is defined as echocardiography that is requested
by, reported to, and acted upon by general practitioners (GPs). Echocardiography provides
information about cardiac anatomy (e.g. volumes, geometry, mass) and function (e.g.
left ventricular function and wall motion, valvular function, right ventricular function,
pulmonary artery pressure, pericardium).
In the population referred by the GPs, the pretest likelihood of disease is much lower
than in the (prescreened) hospital population. Thus OAE is mainly used as a screening
tool to exclude clinically relevant abnormalities.
The most common indications for OAE are assessment of asymptomatic murmurs, breathlessness
and suspected heart failure. OAE is able to exclude significant valvular heart disease,
with the exception of dynamic, exercise-related mitral regurgitation.
OAE is also valuable in a breathless patient if left ventricular (LV) dysfunction
(ejection fraction <40 %) is found, leading to a management change, e.g. starting
an ACE inhibitor and β-blocker. However, a normal systolic LV function in a breathless
patient does not exclude a cardiac cause of breathlessness, as this may be caused
by diastolic LV dysfunction, ischaemia or paroxysmal heart rhythm problems. In such
cases, the echocardiographic examination needs to be interpreted in the context of
clinical history and examination, ECG, exercise ECG or other tests.
Van Gurp et al. describe their experience with OAE, which was set up independently
from the regional hospitals [1]. The aim of the study was to demonstrate that OAE
reduces the number of referrals to the cardiologist and found a decrease in intended
referrals within a mean follow-up of 4 months (92 % vs. 34 %, p < 0.001). However,
the aim of the study should have been: reducing the number of referrals, without compromising
patient care. This means that one should also investigate subsequent patient management
(change in medication), delayed referrals and hospitalisations. Ideally, this should
have been investigated in a randomised controlled trial.
The indication for echocardiography (and potential referral to the cardiologist) in
the present study was suspected valve disease in the majority of cases and, less often,
suspected heart failure: 81 (55 %) and 55 (35 %), respectively. However, one would
expect a much higher number of heart failure indications, as 54 GP practices participated.
Each year approximately 7 patients are expected to develop heart failure for the first
time in a Dutch average general practice of 2350 patients. Therefore, the OAE indication
of suspected heart failure should have been 7 times higher, i.e. circa 375 patients
instead of 55 [2]. This underutilisation of OAE in suspected heart failure is also
obvious in other studies [3–5].
What are the reasons for this underutilisation of OAE for the indication of suspected
heart failure?
Barriers to an accurate diagnosis include: lack of confidence in interpreting the
results of technical echo reports, inertia or fear of initiating action because of
anxieties about committing to an intensive course of action, such as investigations,
initiation, titration and monitoring of treatment, or patients’ choices, including
reluctance to be investigated or treated further [6].
According to the heart failure guideline of the Dutch Association of General Practitioners,
in case of suspected heart failure first an ECG and NT-proBNP should be performed.
If the diagnosis of heart failure cannot be excluded by ECG and (NT-pro) BNP, echocardiography
should always be carried out for further diagnosis or to determine the cause of heart
failure. In the study by Van Gurp et al., neither an ECG nor NT-proBNP were performed
before referral for OAE in 1:4 patients with suspected heart failure, in 55 % NT-proBNP
was performed and in 62 % an ECG, indicating a suboptimal adherence to heart failure
guidelines.
Although it is important to diagnose heart failure, which can be treated according
to protocol by a GP, it is even more important to assess and address the cause of
heart failure. No data are provided in the present study on the cause of heart failure
and how this was addressed.
Moreover, the present study provides no information on patient treatment as a result
of echocardiographic findings. However, a cross-sectional observational study, in
a representative sample of 357 patients diagnosed with heart failure from 42 GP practices
in the Netherlands (mean age 75 years, 77 % in NYHA class 1 or 2), found that 76.5 %
of patients received diuretics. ACE inhibitors were prescribed in 40.6 % and angiotensin-II
receptor blockers in 20.7 %; β-blockers were prescribed to 54.6 %, while 24.9 % received
spironolactone. Only small percentages (10–25 %) of patients received drugs in the
suggested daily target doses [7].
How to proceed with OAE?
Important issues for OAE are:
A local (regional or nationwide) consensus document should be created, including generally
accepted indications for OAE (e.g. suspected heart failure and assessment of asymptomatic
murmurs), the required pretest information, the level of training of ultrasound technicians,
the way of reporting, and cardiologist advice for further treatment. In this consensus
document barriers to be overcome before implementation of OAE in primary and secondary
care should be identified and addressed [5]. Just as in the UK, it could turn out
that not OAE, but a rapid access one-stop heart failure clinic (independent treatment
centre) is the favoured model of care, offering diagnosis and initial treatment, whilst
liaising with GPs and nurses for maintenance and palliative services [8]. In the present
study OAE was set up independently from the regional hospitals, which does not seem
the right way to go.
The echocardiographic examination should be performed by individuals with sufficient
training and accreditation in echocardiography. In the present study it is stated
that at first echocardiographic examinations were suboptimal due to lack of routine
and experience of the ultrasound technicians; their accreditation level is not mentioned.
Reports of OAE should contain a minimum of information, relevant for treatment according
to the guidelines. The report should be devoid of trivial abnormalities that confuse
the GPs, such as mild thickening of the aortic valve in the elderly or mild MR or
TR. All echo reports should be provided with a cardiologist’s advice. In order to
give good advice, the cardiologist needs information on relevant general and cardiovascular
history, medication, physical examination, ECG and NT-proBNP. In the study by Van
Gurp et al. the cardiologists received insufficient information, i.e. they only had
access to the indication and patient-reported height and weight. In case of heart
failure also the cause of heart failure should be searched for and mentioned.
An intensive collaboration between first-line (GPs) and second-line (cardiologists)
is mandatory to prevent a decrease in the quality of patient care, both as to optimal
treatment and in a search for the (potentially reversible) cause of heart failure.
Additional research is necessary, preferably a randomised controlled trial with clinical
outcomes and cost-effectiveness analysis.
Currently, in the Netherlands, OAE is the result of competition in patient care and
a perceived long waiting list for referral to the cardiologist. However, for society,
low-threshold OAE might turn out to be more expensive due to more unnecessary echocardiographic
examinations.
Apart from that, the legal consequences of an unfavourable clinical course after OAE
are yet unclear.
The danger of OAE is that it leads to a ‘low-budget pseudo-consult’ of the cardiologist,
whilst the patient thinks he is getting a state-of-the-art treatment.