Introduction
The complexity of the individual patient and organization of medical practice results
in important institutional and country quality of care variability.
1–17
Attempts to assess the quality of clinical practice have established rating systems
that may yield completely different results and rating for the same hospital during
the same period of time, adding confusion rather than help to prove their usefulness
and, questioning whether existing measures can actually measure quality.
18–35
Most important, benchmarking may be associated with progressive improvement both in
performance and outcomes,
18,26,28,36–38
highlighting the relevance of standardization of quality measures and the responsibility
of scientific societies.
Objectives
The Spanish Society of Cardiology (SSC) and the Spanish Society of Thoracic and Cardiovascular
Surgery (SSTCS) organized a task force to identify and define two sets of quality
metrics in hospital cardiology practice: (i) outcome measures (metrics of the final
quality of the practice of cardiology) and (ii) performance measures (metrics of clinical
practice which are known to positively influence desirable outcomes). Beyond this
objective, Scientific Societies and Health Care Authorities should be responsible
for the implementation of programmes to measure quality, ensure the quality of the
data, benchmarking, and certification/accreditation of cardiology services.
Methods
All European Society of Cardiology (ESC)
32
and American Heart Association/American College of Cardiology
33
guidelines were reviewed and recommendations related to quality standards were included
in the document.
Grading of quality markers
Three levels were established both for class recommendation and level of evidence
considering (i) clinical and practical relevance, (ii) source and difficulty to obtain
the information, (iii) difficulty to audit and ascertain the information, and (iv)
evidence in the literature (Table 1
). Mortality and stroke were considered as self-evident. To avoid confusion with general
clinical practice guidelines nomenclature, Class of recommendation was graded in 1,
2, and 3 grades instead of I, II, and III.
Table 1
Grading of quality markers/metrics
Class of recommendation
Level of evidence
Class
Relevance
Data source. Reliability and difficulty to obtain
Auditable
Level
Evidence
1
Mayor outcomes (usual outcomes in clinical trials)
Data available in all hospitals by law (e.g. minimal health care database)
Obligatory registries
Data public, available on file
Obligatory registries
A
Self-evident
Level A in ESC/AHA-ACC guidelines
Recommendations of regulatory agencies
2
Outcome surrogates
Class I in guidelines other than major outcomes in clinical trials
Voluntary registries including all patients
Difficult to obtain; may be unreliable
Voluntary disclosures
Difficult to audit
B
Level B in guidelines
3
Class < I in guidelines
Opinions
Voluntary registries (not including all consecutive patients)
Opinions, surveys
Data on file but difficult to obtain
Data impossible to obtain in majority of hospitals
C
Level C in guidelines
Opinion surveys
Recommended by other agencies for quality grading
Type of hospital
For quality benchmarking, the task force established three types of hospitals defined
as low, intermediate, and high complexity according to their organization, resources,
and the need to transfer patients to other hospitals.
Clusters to assess overall quality in clinical practice
Quality of care parameters may be grouped in clusters including institution characteristics,
available technologies, staffing of the hospital and cardiac unit, organization, certification
and accreditation, reputation and patients opinion.
17,39,40
All of them may influence outcomes, most are clearly identified in guidelines for
clinical practice and all should be taken in consideration in every hospital.
Main markers to measure quality of results (measures of outcomes) in clinical cardiology
practice
Clinical outcomes are the ultimate measure of quality of care in cardiology and there
is no excuse to ignore them. The main outcomes in cardiology trials (mortality, hospitalization,
myocardial infarction/re-infarction, and stroke) constitute the strongest reference
for guideline recommendations.
29,30,32,33,41–47
Ideally, an outcome at a pre-defined follow-up (e.g. 30 days after index hospitalization)
is preferred instead of during hospitalization, but this may be difficult or impossible
to ascertain except in well-organized dedicated registries. Outcomes should be measured
in uniform groups of patients and need corrections for case mix complexity (Table
2
).
Table 2
Principal markers frequently used to assess overall quality of results in clinical
practice
Metric
Relevance
Difficulty
Auditable
Evidence
Comments
All-cause mortality
1
1
1
A
Self-evident. Reliable only in auditable registries/databases
Cardiovascular mortality
1
2
2
A
Difficult to ascertain. Needs adjudication
Number of days in hospital
1
2
2
A
Reason for hospitalization dependent of health care systems, individual preferences
and co-morbidities
Number of days in any hospital 30 days after index hospitalization preferred to days
in hospital until discharge
Stroke
1
2
2
A
Difficult to ascertain. Needs adjudication
No reliable risk scores for corrections between different hospitals
Re-infarction
1
2
2
A
Difficult to ascertain. Needs adjudication
Safety (major bleeding, severe infections, medical errors, etc.)
1
2
2
A
Difficult to ascertain. Needs adjudication
Mortality
Mortality constitutes the first and most important metric recommended by this task
force to measure quality results in clinical practice. The relevance of mortality
is self-evident, remains the most important outcome measure in clinical trials designed
to change clinical practice, and is the most powerful evidence to support recommendations
in practice guidelines. In many clinical settings, it is related to guideline adherence
as well as performance measures,
2,47
it is included in different programmes that evaluate quality of care,
3–7,10,13,16,19,21,31
and certainly it can be audited (Class of recommendation 1 and Level of evidence A).
All-cause mortality during the index hospitalization is the recommended metric by
this Task Force, as different causes of mortality need adjudication for uniformity
and this will not be possible except in dedicated registries. Mortality, particularly
in acute coronary syndromes (ACS), is not evenly distributed, i.e. mortality for stable
patients is currently around 3–5%, while rescucitated or intubated patients have a
lethality of 35–50%. Thus, mean mortality rates have to be adjusted for case complexity
to be fair for centres with a large number of ACS patients in shock or after cardiopulmonary
resuscitation.
Length of hospitalization stay and re-admission rates
Length of hospitalization stay and re-admission rates constitute the second metric
recommended by this Task Force. Hospitalization reflects quality of care, impacts
health care cost, is commonly used in quality programmes,
2,41–47
and is also included in many quality control databases. On the other hand, length
of stay may not be reliable as an outcome metric to compare results of practice in
different countries/areas where hospitalization may be driven not only by medical
but also by administrative and social reasons. In addition, it may be dependent of
other conditions or comorbidities, always difficult to properly determine. For this
reason, hospitalization is recommended as a quality metric only when hospitals participate
in a prospective, dedicated registry, where criteria for admission and discharge are
pre-defined or the cluster of hospitals is uniform (Class of recommendation 2 and
Level of evidence B).
Myocardial infarction
In-hospital or post-discharge myocardial infarction is one of the components of the
main outcomes in clinical trials and registries in patients with ischaemic heart disease.
However, it may be a poor metric for outcomes due to the difficulties to standardize
the diagnosis in large populations, in particular during the first few days after
hospital admission for ACS,
2,41–48
and should only be used in dedicated, prospective controlled registries (Class of
recommendation 2 and Level of evidence B).
Stroke
Disabling stroke is self-relevant, is related with iatrogenia, percutaneous interventions
(PCI) surgery, and the use of antithrombotic therapy. Stroke is a metric included
in registries and some quality programmes.
49
However, minor forms of stroke are difficult to diagnose without the routine use of
brain imaging techniques, there are not reliable scales for stroke risk in different
clinical settings and this metric may represent a confounding factor for benchmarking
if not centrally adjudicated.
50–52
Stroke is only recommended as a quality measure when considering well organized, controlled,
and audited registries (Class of recommendation 2 and Level of evidence B).
Safety
Safety parameters such as major bleeding, medical errors, infections, cardiac tamponade
during PCI, and other relevant clinical complications of clinical practice should
be considered in quality performance reports. Again, the complexity of achieving uniform
diagnosis and reporting in large number of hospitals preclude the use of safety parameters
for benchmarking of quality except when data are prospectively obtained in dedicated,
controlled registries (Class of recommendation 2 and Level of evidence B).
Adjustment of outcomes metrics
Selection of uniform populations
Comparisons should be made only between similar hospitals and in selected, well-defined,
high-risk-specific populations with prognosis known to be dependent on overall cardiology
management (Groups of Related Diagnosis or GRDs).
39,53–55
Extreme high-risk and low-prevalence groups of patients should be excluded from analysis
rather than corrected for risk.
53,54
Sometimes this information is not well reflected in registries or databases, stressing
the importance of dedicated databases for the measurement of quality outcomes.
54
Table 3
shows the recommended populations for benchmarking.
Table 3
Recommended measures to assess quality of results in clinical practice
Metric
Suggested reference value
Relevance
Difficulty
Auditable
Evidence
References
Mortality
a
STEMI mortality (excluding Killip IV class patients and patients after cardiopulmonary
resuscitation)
<5% (a)
1
1
1
A
41,42
Non-STE-ACS mortality (excluding Killip IV class patients and patients after cardiopulmonary
resuscitation)
<3% (a)
1
1
1
A
43,44
Staged PCI mortality
<1% (a)
1
1
1
A
56
TAVI mortality
<6% (a)
1
1
1
A
57,58
VT after AMI and other complex catheter ablation mortality
<3% (a)
1
1
1
A
59–61
Pacemaker, ICD, CRT implant mortality
<1% (a)
1
1
1
A
62,63
Heart failure mortality
<7% (a)
1
1
1
A
67
Staged first aortic valve surgery replacement mortality (excluding TAVI)
<5% (a)<7% (b)
1
1
1
A
64–66
Staged first mitral valve surgery replacement mortality
<7% (a)<9% (b)
1
1
1
A
64–66
Staged first mitral valve surgery repair mortality
<3% (a)<5% (b)
1
1
1
A
64–66
Staged first CABG (without combined surgery) mortality
<3% (a)<5% (b)
1
1
1
A
64–66
Staged first combined CABG + AVR mortality
<6% (a)<8% (b)
1
1
1
A
64–66
Heart transplant
<15% (a)(c)
1
1
1
A
184
Hospitalization
b
STEMI number of days in hospital
<10
2
2
1
A
41,42
Non-STE-ACS number of days in hospital
<10
2
2
1
A
43,44
Heart failure number of days in hospital
<9
2
2
1
A
5,11,18,67
Staged first CABG, aortic or mitral surgery number of days in hospital
<15
2
2
1
A
64,68,69
Rehospitalization after ACS, heart failure, or surgery as abovec
Less than mean value in national registries
Reference values are orientative. For benchmarking, a target reference value less
than median value in participating hospitals is strongly suggested.
aMortality: 30 days all-cause mortality is preferred over mortality before hospital
discharge only if reliable data can be obtained.
b
Hospitalization: the number of days in any hospital during the first 30 days after
index hospitalization is preferred over number of days from hospitalization to discharge.
c
Rehospitalization: unplanned readmission for any cause to any acute care hospital
within 30 days of discharge from a hospitalization. (a) Observed mortality (mean value).
(b) Expected mortality corrected for the logistic euroscore for this population. (c)
Mortality or re-transplant. CABG, coronary artery bypass-grafting; TAVI, transaortic
valve implant.
Risk adjustment
The use of specific and validated risk scores recommended in guidelines (GRACE or
TIMI risk scores for ACS,
70,71
Euro2 risk score,
72–74
and others
75–77
) will provide further refinement and make the metrics reliable for benchmarking.
Some are too complex and difficult to assess in large populations (e.g. including
biological markers not universally used
74–77
). In such circumstances, adjusted models considering common risk factors are recommended.
16,78
Measures of the performance of the practice of clinical cardiology: quality markers
related with better results in clinical practice (performance measures)
These metrics are the reference for a better health care organization but must not
be considered as important as outcomes. Benchmarking of some of these parameters may
be difficult, and obtaining the appropriate information may require a dedicated database
very difficult to standardize or complete, and even more difficult to audit accurately.
Accordingly, the most important use of these parameters is for internal quality controls,
not for benchmarking different hospitals. Eight different sections have been identified:
Clinical cardiology
Some quality markers are recommended for the accreditation of cardiology units of
all hospitals (e.g. staffing, technology, volumes); others are directed to control
internal quality or to identify problems and opportunities for improvement and are
recommended for all hospitals.
79–121
The most relevant recommendations are the use of local protocols for diagnosis and
treatment, based in the ESC/AHA or country-specific guidelines and approved by the
hospital.
32,33,89
Teamwork with internal medicine and other related specialties, with special reference
to primary care should constitute a priority.
81–88
Cardiac imaging
Cardiac imaging constitutes the core for diagnosis in cardiology.
122–137
Transthoracic echocardiography performed by well-trained cardiologists is recommended
in all patients, in all hospitals. More complex techniques require specific training,
accreditation and certification are highly recommended and may benefit from teamwork
with radiologists (nuclear imaging, cardiac computed tomography, and cardiovascular
magnetic resonance). Accreditation of image laboratories by the ESC or other official
accreditation agencies is recommended. Quality controls include accreditation, low
inter-observer variability, timely performed studies (waiting list's), and prompt
systematic reports.
Acute cardiac care measures related to better results in clinical practice
Acute cardiac care requires teamwork with out-of-hospital professionals, emergency
departments, internal medicine, and intensive care physicians following well-defined
protocols for common cardiac conditions such as acute myocardial infarction (AMI)
and ACS.
41–44,90,138
Patients with ST elevation myocardial infarction (STEMI) should be referred immediately
and only to hospitals with available primary PCI. Well-trained nurses are of upmost
importance in emergency departments, medical wards in type II and III hospitals, and
intensive care units. Time do first medical contact to balloon or needle, risk score
determinations, revascularization in intermediate and high-risk patients, and adherence
to guidelines recommended medication are the most relevant quality performance measures.
Outcomes include mortality in STEMI and ACS. Local safety controls should focus on
antithrombotic complications.
Interventional cardiology
The results of percutaneous cardiac interventions are highly dependent on the expertise
and training of interventional cardiologists, as well as on the volume of performed
procedures at each hospital and by individual interventional cardiologists.
41–44,56–58,139–149
Complex cases should be only treated in hospitals with cardiac surgery support.
142
Low volume, highly complex interventions [transaortic valve implant (TAVI) closure
of left atrial appendage and foramen ovale, valvular and adult congenital heart disease
interventions] should be considered only in selected type III hospitals with specific
training and accreditation. Adherence to local protocols based on guidelines and heart
team decisions for non-urgent interventions should be considered in all cases. Outcome
metrics include STEMI and ACS mortality, as well as TAVI mortality and elective PCI
mortality. The main safety control is focused on bleeding and vascular complications
requiring surgery or extended length of stay.
Electrophysiology and complex arrhythmia
Interventional treatment of complex arrhythmias (e.g. atrial fibrillation) requires
accreditation of both laboratory and electrophysiologists.
59–63,150–161
Indication for ablation should be established after a Heart Team approach that adheres
to the guideline recommendations. Outcome targets should include complex electrophysiological
procedures and device implantation mortality. Safety should focus on complications
requiring surgery, transfusions, or prolongation of hospitalization.
Heart failure
Diagnosis and treatment of heart failure is rapidly changing and increasing in complexity
and adherence to guidelines is likely to assure better outcomes including survival.
5,18,45,46,67,162–164
Cardiac care must be continued after discharge from hospital in all cases. Teamwork
as opposed to admitting patients in cardiology or internal medicine is crucial and
strongly recommended. A heart failure unit adapted to local characteristics of the
hospital is always highly recommended. Outcomes include mortality and readmissions
to the hospital.
Cardiac rehabilitation
Cardiac rehabilitation is more than controlled exercise training.
41–44,165–180
The main objective should be the patient education for long-term changes related to
life-style, adherence to medical treatment for the specific condition and use of appropriate
secondary prevention strategies. Cardiac rehabilitation units or programmes should
be implemented to offer all patients appropriate counselling and follow-up for secondary
prevention. Teamwork especially with general physicians is essential. Quality controls
should include access to rehabilitation programmes for patients with ischaemic heart
disease and adherence to guidelines during long-term follow-up.
Cardiac surgery
Quality controls in cardiac surgery have already been implemented in some countries.
64–66,181–184
Heart Team approach is recommended in all cases; hospital volumes, training and expertise
of surgeons, anaesthesiologist, nurses and referring cardiologists highly impact outcomes.
Outcomes are relatively easy to measure and should focus on mortality and length of
hospitalization in prevalent, well-defined surgical procedures such as CABG, aortic
and mitral valve staged, first time surgery.
Current limitations
Capture of information
Registries and databases currently used for benchmarking may not have the appropriate
quality. Audited, dedicated, prospective mandatory reports would be arguably the best
way of capturing simple but essential/core information.
185
This document is based on the ESC and AHA-ACC guidelines recommendations. Nevertheless,
the document is mainly intended for the health care system in Spain. It may not apply
in other countries with different health care systems. There is a need for defining
quality standards universally acceptable to compare quality of care between different
health care systems and countries, within and out of the European Union and ESC.
Future challenges
Unmet needs and opportunities for improvement include: (i) standardization of data
(data capture and availability, risk corrections, target values and reporting); (ii)
standardization of audits to ascertain data quality; (iii) universal participation;
(iv) identification of quality metrics for outpatient clinical practice
68,69,186
and long-term follow-up; and (v) refinement of the quality metrics considering the
feed back from participants in benchmarking programmes.