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## Complete Summary

#### GUIDELINE TITLE

Shortness of breath\--suspected cardiac origin.

#### BIBLIOGRAPHIC SOURCE(S)

Schoepf UJ, Yucel EK, Bettmann MA, Casciani T, Gomes AS, Grollman JH,
Holtzman SR, Polak JF, Sacks D, Stanford W, Jaff M, Moneta GL, Expert
Panel on Cardiovascular Imaging. Shortness of breath \-- suspected
cardiac origin. \[online publication\]. Reston (VA): American College of
Radiology (ACR); 2006. 5 p. \[34 references\]

#### GUIDELINE STATUS

This is the current release of the guideline.

This guideline updates a previous version: Boxt LM, Bettmann MA, Gomes
AS, Grollman J, Henkin RE, Higgins CB, Kelley MJ, Needleman L,
Pagan-Marin H, Polak JF, Stanford W, Wexler L. Shortness of
breath\--suspected cardiac origin. American College of Radiology. ACR
Appropriateness Criteria. Radiology 2000 Jun;215(Suppl):23-7.

The appropriateness criteria are reviewed annually and updated by the
panels as needed, depending on introduction of new and highly
significant scientific evidence.

### COMPLETE SUMMARY CONTENT

 SCOPE\
 METHODOLOGY - including Rating Scheme and Cost Analysis\
 RECOMMENDATIONS\
 EVIDENCE SUPPORTING THE RECOMMENDATIONS\
 BENEFITS/HARMS OF IMPLEMENTING THE GUIDELINE RECOMMENDATIONS\
 QUALIFYING STATEMENTS\
 IMPLEMENTATION OF THE GUIDELINE\
 INSTITUTE OF MEDICINE (IOM) NATIONAL HEALTHCARE QUALITY REPORT
CATEGORIES\
 IDENTIFYING INFORMATION AND AVAILABILITY\
 DISCLAIMER

### SCOPE

#### DISEASE/CONDITION(S)

Shortness of breath, suspected cardiac origin

#### GUIDELINE CATEGORY

Diagnosis\
Evaluation

#### CLINICAL SPECIALTY

Cardiology\
Emergency Medicine\
Family Practice\
Internal Medicine\
Radiology

#### INTENDED USERS

Health Plans\
Hospitals\
Managed Care Organizations\
Physicians\
Utilization Management

#### GUIDELINE OBJECTIVE(S)

To evaluate the appropriateness of initial radiologic examinations for
patients with shortness of breath, suspected cardiac origin

#### TARGET POPULATION

Patients with shortness of breath, suspected cardiac origin

#### INTERVENTIONS AND PRACTICES CONSIDERED

1.  X-ray, chest

2.  Ultrasound

    -   Transthoracic echocardiography (TTE)

    -   Transesophageal echocardiography (TEE)

    -   Peripheral venous

3.  Nuclear medicine (NUC)

    -   Radionuclide myocardial perfusion scan, stress

    -   Radionuclide ventriculogram (RNV)

    -   Radionuclide ventilation/perfusion (VQ) scan

4.  Invasive (INV)

    -   Coronary angiography

    -   Left ventriculography, heart

    -   Angiography, lung

5.  Computed tomography (CT)

    -   Chest

    -   Heart, electrocardiogram (ECG)-gated

6.  Magnetic resonance imaging (MRI), heart

#### MAJOR OUTCOMES CONSIDERED

Utility of radiologic examinations in differential diagnosis

### METHODOLOGY

#### METHODS USED TO COLLECT/SELECT EVIDENCE

Searches of Electronic Databases

#### DESCRIPTION OF METHODS USED TO COLLECT/SELECT THE EVIDENCE

The guideline developer performed literature searches of recent
peer-reviewed medical journals, and the major applicable articles were
identified and collected.

#### NUMBER OF SOURCE DOCUMENTS

The total number of source documents identified as the result of the
literature search is not known.

#### METHODS USED TO ASSESS THE QUALITY AND STRENGTH OF THE EVIDENCE

Weighting According to a Rating Scheme (Scheme Not Given)

#### RATING SCHEME FOR THE STRENGTH OF THE EVIDENCE

Not stated

#### METHODS USED TO ANALYZE THE EVIDENCE

Systematic Review with Evidence Tables

#### DESCRIPTION OF THE METHODS USED TO ANALYZE THE EVIDENCE

One or two topic leaders within a panel assume the responsibility of
developing an evidence table for each clinical condition, based on
analysis of the current literature. These tables serve as a basis for
developing a narrative specific to each clinical condition.

#### METHODS USED TO FORMULATE THE RECOMMENDATIONS

Expert Consensus (Delphi)

#### DESCRIPTION OF METHODS USED TO FORMULATE THE RECOMMENDATIONS

Since data available from existing scientific studies are usually
insufficient for meta-analysis, broad-based consensus techniques are
needed to reach agreement in the formulation of the appropriateness
criteria. The American College of Radiology (ACR) Appropriateness
Criteria panels use a modified Delphi technique to arrive at consensus.
Serial surveys are conducted by distributing questionnaires to
consolidate expert opinions within each panel. These questionnaires are
distributed to the participants along with the evidence table and
narrative as developed by the topic leader(s). Questionnaires are
completed by the participants in their own professional setting without
influence of the other members. Voting is conducted using a scoring
system from 1-9, indicating the least to the most appropriate imaging
examination or therapeutic procedure. The survey results are collected,
tabulated in anonymous fashion, and redistributed after each round. A
maximum of three rounds is conducted and opinions are unified to the
highest degree possible. Eighty percent agreement is considered a
consensus. This modified Delphi technique enables individual, unbiased
expression, is economical, easy to understand, and relatively simple to
conduct.

If consensus cannot be reached by the Delphi technique, the panel is
convened and group consensus techniques are utilized. The strengths and
weaknesses of each test or procedure are discussed and consensus reached
whenever possible. If \"No consensus\" appears in the rating column,
reasons for this decision are added to the comment sections.

#### RATING SCHEME FOR THE STRENGTH OF THE RECOMMENDATIONS

Not applicable

#### COST ANALYSIS

A formal cost analysis was not performed and published cost analyses
were not reviewed.

#### METHOD OF GUIDELINE VALIDATION

Internal Peer Review

#### DESCRIPTION OF METHOD OF GUIDELINE VALIDATION

Criteria developed by the Expert Panels are reviewed by the American
College of Radiology (ACR) Committee on Appropriateness Criteria.

### RECOMMENDATIONS

#### MAJOR RECOMMENDATIONS

**ACR Appropriateness Criteria®**

**Clinical Condition: Shortness of Breath\--Suspected Cardiac Origin**

  ---------------------------------------------------------------------------
  **Radiologic Exam    **Appropriateness   **Comments**
  Procedure**          Rating**            
  -------------------- ------------------- ----------------------------------
  X-ray, chest         9                   For evaluation of pulmonary
                                           vascularity and edema

  US, heart,           8                    
  transthoracic (TTE)                      

  NUC, heart,          7                    
  radionuclide                             
  myocardial perfusion                     
  scan, stress                             

  NUC, heart,          6                    
  radionuclide                             
  ventriculogram (RNV)                     

  INV, heart, coronary 6                    
  angiography                              

  INV, heart,          6                    
  ventriculography,                        
  left                                     

  US, heart,           5                    
  transesophageal                          
  (TEE)                                    

  CT, chest            5                   For evaluation of pulmonary
                                           vascularity and edema

  CT, heart, ECG-gated 5                   Multidetector with maximal
                                           temporal and spatial resolution.
                                           For detection of coronary artery
                                           disease.

  MRI, heart           4                    

  US, peripheral       3                   Only if DVT or PE suspected
  venous                                   

  NUC, lung,           3                   Only if PE suspected
  radionuclide VQ scan                     

  INV, lung,           2                   Only if PE suspected
  angiography                              

  ***Appropriateness                       
  Criteria Scale*\                         
  1 2 3 4 5 6 7 8 9\                       
  1 = Least                                
  appropriate 9 = Most                     
  appropriate**                            
  ---------------------------------------------------------------------------

Note: Abbreviations used in the table are listed at the end of the
\"Major Recommendations\" field.

Shortness of breath, or dyspnea, has no precise definition, and patients
vary in their attempts to describe the sensation. It may have a
respiratory or cardiac origin and may be associated with deconditioning,
anemia, or anxiety. Some patients have a combination of these factors
that produce dyspnea at rest, after exercise, or in certain positions
(orthopnea, trepopnea, or platypnea, i.e., recumbent, on one side, or in
the upright position). Dyspnea may have an acute onset or may be chronic
and is more common in the elderly. Breathlessness has been described as
\"\...difficult, labored, uncomfortable breathing.\"

It is not always easy to distinguish between the various causes of
dyspnea, although history, physical examination, and simple laboratory
tests usually provide a working diagnosis. The electrocardiogram, plain
chest radiograph, and complete blood count are part of the initial
diagnostic workup. Simple pulmonary function testing and oximetry are
important tests when chronic obstructive pulmonary disease (COPD) or
asthma is suspected. Cardiopulmonary exercise testing, with measurement
of peak oxygen uptake, is useful in this assessment when combinations of
cardiac and respiratory causes are being considered.

Congestive heart failure (CHF) is the most common cardiac cause of
dyspnea. CHF may involve both systolic and diastolic left ventricular
dysfunction. Although we commonly think of systolic dysfunction as most
important because it produces decreased cardiac output, it is the
diastolic dysfunction that appears to be associated with the symptom of
dyspnea and with reduced functional capacity under the New York Heart
Association (NYHA) grading system in some cases. Some patients may have
CHF and dyspnea with normal ejection fractions and can be classified as
having diastolic heart failure. Ischemic heart disease is the most
common cause of CHF, but other etiologies include valvular heart
disease, left-to-right shunts, hypertension and hypertrophic myopathies,
infiltrative disorders such as amyloid disease, right ventricular
failure or overload with abnormal septal intrusion on the left
ventricle, pericardial disease with restriction in diastolic filling of
the left ventricle (LV) and cardiomyopathies due to alcohol, drugs,
radiation, inflammation, peripartum, or unknown causes (idiopathic).

Imaging studies are invaluable for establishing the diagnosis and, in
many instances, determining the appropriate management strategy. The
plain chest film and echocardiography are the major imaging tools
employed, but radionuclide imaging plays an important role. CT and MRI
have much to offer but have not been used with much frequency to date.
Cardiac angiography and coronary arteriography are invasive imaging
techniques that are used extensively for diagnosing or excluding
ischemic disease and, together with cardiac hemodynamics and
endomyocardial biopsy, are important for precise evaluation of cardiac
function and etiology of cardiomyopathies.

**Radiograph**

The radiograph provides important information about the underlying
etiology of dyspnea at a very moderate cost. Most of the noncardiac
causes related to primary respiratory conditions can be identified.
Cardiomegaly is seen in about half of patients with chronic CHF, and
specific chamber enlargement is helpful in detecting valvular heart
disease. CHF is fairly reliably manifested in the acute situation by
alveolar pulmonary edema or in the chronic situation by interstitial
edema. Elevation of left ventricle end-diastolic pressure (LVEDP),
however, is not always accompanied by signs of interstitial edema,
particularly in patients who have undergone treatment with diuretics and
angiotensin-converting enzyme (ACE) inhibitors, whereas clinical
symptoms and NYHA grade tend to parallel the radiographic findings of
elevated pulmonary capillary wedge pressure (PCWP). Absence of the
radiographic signs of congestion does not ensure a normal LVEDP or PCWP
in patients with chronic CHF. Flow to the upper and lower zones of the
lung can be determined in both upright and supine radiographs by
comparing the ratio of a pulmonary artery to its accompanying bronchus.
The pulmonary artery enlarges relative to the bronchus when flow is
increased. Normally the flow to the lower lobes exceeds that to the
upper lobes with a ratio of less than one in the upper zones and greater
than one in the lower zones. Flow to both the upper and lower zones
increases with pulmonary plethora, as occurs in renal failure or
left-to-right shunts, whereas in impending CHF, upper-zone flow is
increased and lower-zone flow is decreased. This results in what is
commonly referred to as \"pulmonary vascular redistribution.\"

**Echocardiography**

Transthoracic echocardiography (TTE) and transesophageal
echocardiography (TEE) are widely available techniques that play an
extremely important role in evaluating patients with dyspnea of
suspected cardiac origin. LV size, systolic and diastolic function
(contraction and relaxation), wall thickness and texture, and the
presence of valve dysfunction are obtained with a combination of
two-dimensional and color Doppler techniques. Serial studies are easily
performed without radiation exposure. TTE has limitations in imaging
certain body types, while TEE is somewhat invasive and should be
reserved for cases that require better definition of the mitral valve or
when TTE is unsatisfactory. Stress echo studies are useful to detect
regional wall motion abnormalities in ischemic situations. Abnormalities
of diastolic function can be detected in patients with normal heart
size. Pericardial restraint during relaxation can often be inferred.
Pericardial effusion is easily detected, but pericardial thickening and
calcification are not readily seen.

**Radionuclide Imaging**

Equilibrium-gated blood-pool imaging of the left ventricle in systole
and diastole provides reliable and reproducible measurements of ejection
fraction and regional wall motion abnormalities and is useful in
assessing diastolic and systolic performance. In patients undergoing
radionuclide imaging for dyspnea of suspected cardiac origin, dyspnea
appears to be an independent predictor of an increased risk for death
from cardiac causes and from any cause. It is less dependent than
echocardiography on assumptions of ventricular geometry. These studies
are widely available and are relatively expensive. They require exposure
to radiation, have poor spatial resolution, and may be hampered by
cardiac dysrhythmias. Studies can be performed after stress and at rest
to assess ventricular function under conditions designed to provoke
ischemia. Myocardial perfusion imaging with a variety of agents can be
performed at rest and after stress with exercise, dobutamine,
dipyridamole, or adenosine. These studies give generally reliable
results that detect areas of ischemia, infarction, and hibernating
myocardium. They may be useful in patients with dyspnea and suspected
myocardial ischemia for demonstrating regional perfusion abnormalities.

**Computed Tomography**

Conventional CT with contrast infusion gives limited information about
cardiac chamber enlargement. It can detect pericardial calcification and
effusions and is quite useful for detecting pulmonary causes of dyspnea.
Compared to conventional radiography, CT enables superior assessment of
pulmonary vascularity in the context of congestive heart failure. It has
little utility in evaluating cardiac function. Gated studies can be
performed with multidetector row CT, which provides detailed information
on cardiac and general thoracic pathology. Effusions and cardiac tumors
are easily detected. Coronary calcium is visible, and several scoring
systems have been developed that correlate loosely with severity of
coronary artery disease. In addition, such studies can be viewed as
multiple frames over a cardiac cycle or in a cine format. Precise and
reproducible measurements of ventricular volumes, wall thickness, and
regional contraction abnormalities can be made, although multidetector
row CT should not be used primarily for evaluating cardiac function.
ECG-synchronized CT is also emerging as an important tool for the
non-invasive detection of coronary artery stenosis. While currently
there is no literature to support the use of CT for the detection of
coronary artery disease in the setting of shortness of breath with
suspected cardiac origin, it is anticipated that CT of the heart will
prove beneficial in the management of patients with this presentation.
As with all imaging tests involving use of iodinated contrast material,
the diagnostic benefit needs to be weighed against the risk of inducing
or worsening congestive heart failure due to contrast related volume
overload.

**Magnetic Resonance Imaging**

To achieve adequate MRI of the heart, artifacts from cardiac and
respiratory motion and the flow of blood within vessels need to be
corrected. ECG and respiratory gating are required if images are to be
acquired over several heartbeats. Current techniques suggest the
feasibility of producing satisfactory image quality during a single
breathhold or even during a single heartbeat. Cine MRI reveals anatomic
and functional abnormalities of the valves, pericardium, and myocardium
without the need for radiation or contrast administration.

Currently there are few proven indications for MRI in the setting of
acute dyspnea. Research into applying MRI to functional studies of
myocardial contraction and diastolic relaxation have shown promise to
accurately characterize the functional abnormality and to provide
specific tissue characterization of certain infiltrative
cardiomyopathies. Until these techniques are studied in more detail and
become available to the general public, MRI\'s clinical applicability
remains unproven.

**Invasive Techniques**

Physiological studies with hemodynamic monitoring of right heart and
pulmonary wedge pressures are often useful in detecting a cardiac cause
of dyspnea when the etiology is obscure. Angiography may play a role in
detecting normal coronary arteries in patients with heart failure due to
cardiomyopathy or in revealing coronary disease when the clinical
suspicion is low. Left ventricular function is more easily determined
noninvasively, but left ventriculography may reveal regional wall motion
abnormalities not detected by echocardiography or radionuclide
angiography.

**Summary**

Dyspnea is a poorly understood symptom that may have pulmonary, cardiac,
or psychological causes. The simple chest radiograph is most useful in
separating cardiac from pulmonary disease, and the echocardiogram has
emerged as the noninvasive modality of choice for determining left
ventricular function. Radiographs and echocardiographs are widely
available, have virtually no risk, and are suitable for serial studies.
Nuclear imaging is widely used as a method for study of left ventricular
function as well as myocardial perfusion. Multidetector row CT and
cardiac MRI have a variety of limitations, and their efficacy has not
been validated on sufficiently large populations, even though they have
potential for evaluating anatomy and function.

**Abbreviations**

-   CT, computed tomography

-   DVT, deep vein thrombosis

-   ECG, electrocardiogram

-   INV, invasive

-   MRI, magnetic resonance imaging

-   NUC, nuclear medicine

-   PE, pulmonary embolism

-   US, ultrasound

-   VQ, ventilation/perfusion

#### CLINICAL ALGORITHM(S)

Algorithms were not developed from criteria guidelines.

### EVIDENCE SUPPORTING THE RECOMMENDATIONS

#### TYPE OF EVIDENCE SUPPORTING THE RECOMMENDATIONS

The recommendations are based on analysis of the current literature and
expert panel consensus.

### BENEFITS/HARMS OF IMPLEMENTING THE GUIDELINE RECOMMENDATIONS

#### POTENTIAL BENEFITS

Selection of appropriate initial radiologic imaging procedures to aid in
differential diagnosis of patients with shortness of breath, suspected
cardiac origin

#### POTENTIAL HARMS

As with all imaging tests involving use of iodinated contrast material,
the diagnostic benefit of *conventional computed tomography (CT)* with
contrast infusion needs to be weighed against the risk of inducing or
worsening congestive heart failure due to contrast related volume
overload.

### QUALIFYING STATEMENTS

#### QUALIFYING STATEMENTS

An American College of Radiology (ACR) Committee on Appropriateness
Criteria and its expert panels have developed criteria for determining
appropriate imaging examinations for diagnosis and treatment of
specified medical condition(s). These criteria are intended to guide
radiologists, radiation oncologists, and referring physicians in making
decisions regarding radiologic imaging and treatment. Generally, the
complexity and severity of a patient\'s clinical condition should
dictate the selection of appropriate imaging procedures or treatments.
Only those exams generally used for evaluation of the patient\'s
condition are ranked. Other imaging studies necessary to evaluate other
co-existent diseases or other medical consequences of this condition are
not considered in this document. The availability of equipment or
personnel may influence the selection of appropriate imaging procedures
or treatments. Imaging techniques classified as investigational by the
U.S. Food and Drug Administration (FDA) have not been considered in
developing these criteria; however, study of new equipment and
applications should be encouraged. The ultimate decision regarding the
appropriateness of any specific radiologic examination or treatment must
be made by the referring physician and radiologist in light of all the
circumstances presented in an individual examination.

### IMPLEMENTATION OF THE GUIDELINE

#### DESCRIPTION OF IMPLEMENTATION STRATEGY

An implementation strategy was not provided.

#### IMPLEMENTATION TOOLS

Personal Digital Assistant (PDA) Downloads

For information about
[availability](#identifying-information-and-availability), see the
\"Availability of Companion Documents\" and \"Patient Resources\" fields
below.

### INSTITUTE OF MEDICINE (IOM) NATIONAL HEALTHCARE QUALITY REPORT CATEGORIES

#### IOM CARE NEED

Getting Better

#### IOM DOMAIN

Effectiveness

### IDENTIFYING INFORMATION AND AVAILABILITY

#### BIBLIOGRAPHIC SOURCE(S)

Schoepf UJ, Yucel EK, Bettmann MA, Casciani T, Gomes AS, Grollman JH,
Holtzman SR, Polak JF, Sacks D, Stanford W, Jaff M, Moneta GL, Expert
Panel on Cardiovascular Imaging. Shortness of breath \-- suspected
cardiac origin. \[online publication\]. Reston (VA): American College of
Radiology (ACR); 2006. 5 p. \[34 references\]

#### ADAPTATION

Not applicable: The guideline was not adapted from another source.

#### DATE RELEASED

1995 (revised 2006)

#### GUIDELINE DEVELOPER(S)

American College of Radiology - Medical Specialty Society

#### SOURCE(S) OF FUNDING

The American College of Radiology (ACR) provided the funding and the
resources for these ACR Appropriateness Criteria®.

#### GUIDELINE COMMITTEE

Committee on Appropriateness Criteria, Expert Panel on Cardiovascular
Imaging

#### COMPOSITION OF GROUP THAT AUTHORED THE GUIDELINE

*Panel Members*: U. Joseph Schoepf, MD; E. Kent Yucel, MD; Michael A.
Bettmann, MD; Thomas Casciani, MD; Antoinette S. Gomes, MD; Julius H.
Grollman, MD; Stephen R. Holtzman, MD; Joseph F. Polak, MD, MPH; David
Sacks, MD; William Stanford, MD; Michael Jaff, MD; Gregory L. Moneta, MD

#### FINANCIAL DISCLOSURES/CONFLICTS OF INTEREST

Not stated

#### GUIDELINE STATUS

This is the current release of the guideline.

This guideline updates a previous version: Boxt LM, Bettmann MA, Gomes
AS, Grollman J, Henkin RE, Higgins CB, Kelley MJ, Needleman L,
Pagan-Marin H, Polak JF, Stanford W, Wexler L. Shortness of
breath\--suspected cardiac origin. American College of Radiology. ACR
Appropriateness Criteria. Radiology 2000 Jun;215(Suppl):23-7.

The appropriateness criteria are reviewed annually and updated by the
panels as needed, depending on introduction of new and highly
significant scientific evidence.

#### GUIDELINE AVAILABILITY

Electronic copies: Available in Portable Document Format (PDF) from the
[American College of Radiology (ACR) Web
site](http://www.acr.org/SecondaryMainMenuCategories/quality_safety/app_criteria/pdf/ExpertPanelonCardiovascularImaging/ShortnessofBreathSuspectedCardiacOriginDoc15.aspx).

ACR Appropriateness Criteria® *Anytime*, *Anywhere*™ (PDA application).
Available from the [ACR Web
site](http://www.acr.org/SecondaryMainMenuCategories/ACRStore/FeaturedCategories/QualityandSafety/ac_pda.aspx).

Print copies: Available from the American College of Radiology, 1891
Preston White Drive, Reston, VA 20191. Telephone: (703) 648-8900.

#### AVAILABILITY OF COMPANION DOCUMENTS

The following is available:

-   ACR Appropriateness Criteria®. Background and development. Reston
    (VA): American College of Radiology; 2 p. Electronic copies:
    Available in Portable Document Format (PDF) from the [American
    College of Radiology (ACR) Web
    site](http://www.acr.org/SecondaryMainMenuCategories/quality_safety/app_criteria/pdf/background_dev.aspx).

#### PATIENT RESOURCES

None available

#### NGC STATUS

This summary was completed by ECRI on February 20, 2001. The information
was verified by the guideline developer on March 14, 2001. This summary
was updated by ECRI on August 11, 2006.

#### COPYRIGHT STATEMENT

Instructions for downloading, use, and reproduction of the American
College of Radiology (ACR) Appropriateness Criteria® may be found on the
[ACR Web
site.](http://www.acr.org/SecondaryMainMenuCategories/quality_safety/app_criteria/ACRAppropriatenessCriteriaTermsandConditionsDoc1.aspx)

### DISCLAIMER

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© 1998-2008 National Guideline Clearinghouse

Date Modified: 11/3/2008