In an effort to ensure quality cardiac ultrasound imaging and to avoid unnecessary use of the technology, the American Society of Echocardiography (ASE; Raleigh, North Carolina) and the American College of Cardiology Foundation (ACCF; Washington), in partnership with five other groups, released Appropriateness Criteria for two of the most commonly used cardiac ultrasound techniques —transthoracic (TTE) and transesophageal (TEE) echocardiography — just in time for the 18th annual Scientific Sessions of ASE in Seattle in June.

The TTE/TEE Appropriateness Criteria review common scenarios found in clinical practice and address the appropriateness of ordering echocardiograms for each situation. The criteria address a range of clinical situations in which TTE/TEE might be used, such as for patients presenting with signs and symptoms that could represent heart disease — like murmurs and palpitations — and conditions such as hypertension, stroke, heart valve disease and suspected or known congenital heart disease.

According to the report discussing the new criteria, increases in healthcare costs and the resultant payer concern are among the primary reasons for development of the criteria.

Michael Picard, MD, outgoing president of ASE and leader of the Appropriateness Guidelines Committee, told Cardiovascular Device Update, “The really big issue that both private payers and the government are concerned about is obviously the rising cost of healthcare. Then, if you look at the rising cost of healthcare, the concern is that medical imaging is a big component of that rise, because we are relying more on technology as we care for our patients.”

Family practitioners, he said, order more of these TTEs/TEEs than any other physician group, so the new criteria are really directed at them. And the ASE will be undertaking educational efforts directed at family practitioners to inform them of the instances in which TTEs/TEEs are appropriate for use.

The criteria score each indication for which a TTE/TEE might be used:

• A score of 7-9 indicates that the test is appropriate for a specific indication;

• a score of 4 to 6 would mean that reasonableness of the test is “uncertain” — that is, the “test may be generally acceptable and may be a reasonable approach for the indication”;

• a score of 1 to 3 would signal that a test is inappropriate for the indication.

According to the report, the “relative ease of use and low risk” — meaning that no radiation is involved and it is non-invasive — not only provides “many advantages” to physicians, but it also “create[s] opportunities for overuse and misuse in patients who may not obtain a benefit, or who could have achieved a similar benefit without the addition of the test.”

Concern with overuse

However, Picard said the issue is “not so much misuse as a concern about overuse or stemming the tide... . If we assume that from time to time, there are uses of the technology where it probably isn’t needed, that is, care could continue without [the ultrasound], then we are helping to keep the cost of healthcare in check.”

Additionally, according to the report, the results of such an ultrasound could lead to further downstream tests and “treatment such as unwarranted coronary revascularization or unnecessary repeat follow-up.”

Overall, 14 scenarios cited in the criteria were found to be inappropriate reasons for the performance of the TTE/TEE study.

Echocardiography has long been recognized in the broader medical community as a valuable diagnostic test for the evaluation of cardiac structure and function, ASE said. As both TTE and TEE are relatively easy on the patient, are low risk (meaning not requiring radiation) and provide comprehensive diagnostic information, the opportunity exists for inappropriate use in patients who may not benefit from having the exam.

The Appropriateness Criteria for TTE/TEE should help guide physicians in determining when and how often to use the tests, the organizations said. In general, use of TTE/TEE for the initial evaluation of structure and function was viewed favorably, while routine repeat testing and general screening uses in certain clinical scenarios were viewed less favorably.

The groups developing the criteria said they are intended to increase physicians’ confidence that they are ordering an echocardiogram more appropriately and they said they plan efforts to educate them about when a test may not be necessary.

Inappropriate use impacts resources

Besides issues of cost and unneeded follow-up testing, inappropriate use of TTE and TEE can limit resources for those patients who do need testing, the ASE said.

“For the very first time, we are formally addressing the appropriate use of one of the earliest and most commonly used imaging technologies. Although the concept of proper use of technology is not new, providing physicians with the tools to assess our own practice patterns is a critically important and new undertaking. It gives real meaning to our efforts to promote quality in cardiovascular care,” said Pamela Douglas, MD, chair of the TTE/TEE Appropriateness Criteria Writing Group and a past president of both the American College of Cardiology and ASE.

The ACCF said that, to date, criteria exist for SPECT MPI, CCT and CMR, and now TEE and TTE.

The other groups that partnered with ASE and ACCF to developer the criteria were the American College of Emergency Physicians (Dallas), the American Society of Nuclear Cardiology (Bethesda), the Society for Cardiovascular Angiography and Interventions (Washington), the Society of Cardiovascular Computed Tomography (Washington), and the Society for Cardiovascular Magnetic Resonance (Royal, New Jersey).

The criteria are posted online at or and will be published in print in the July 2007 issue of the Journal of the American Society of Echocardiography and the July 10 issue of the Journal of the American College of Cardiology.

Stress echo for women

In research reports at the ASE meeting, one study indicated that stress echocardiography, a heart ultrasound performed during stress testing, is a more accurate method for identifying women at highest risk for coronary artery disease (CAD) than traditional stress testing and clinical risk factors.

CAD is the No. 1 killer of women, and studies indicate that a woman is 30 times more likely to die of CAD than breast cancer. Unfortunately, women, unlike men, often do not show the classic symptoms of heart attack, such as sweating, chest pain or shooting arm pain, therefore it is more difficult to identify when they have blockages in arteries.

“Our study shows that stress echocardiography can stratify women at the highest risk of coronary artery disease into those that are at risk of having a heart attack or cardiac death. This allows women to receive more focused and appropriate treatment that is customized to their specific risk level and outcomes,” said Farooq Chaudhry, MD, director of echocardiography, associate chief of cardiology, St. Lukes-Roosevelt Hospital Center, Columbia University College of Physicians and Surgeons (New York).

The research, conducted at the University of Nebraska Medical Center (Omaha), found that real-time perfusion echocardiography, a heart ultrasound technique that allows doctors to view the blood flow in the heart muscle, helped identify diabetics without symptoms who are at risk for coronary artery disease.

Traditional heart ultrasound continues to remain the best test for identifying many different abnormalities in the heart. However, being able to assess the blood flow within the heart muscle by using a contrast agent, in addition to defining abnormalities, would be a major breakthrough for diagnosis and treatment of heart diseases.

By looking at the structural abnormalities, pumping function of the heart and the blood flow within the heart muscle, a stress test using heart ultrasound with a contrast agent may allow doctors to diagnose and treat more diabetics with previously unknown blockages of the heart arteries.

Contrast imaging improves echo

Contrast echocardiography, a heart ultrasound study performed with a small intravenous injection of an ultrasound contrast agent, can be used to separate patients presenting with low-risk and non-life threatening chest pain from those who may be experiencing a heart attack. This research shows that myocardial contrast echocardiography (MCE) may more accurately diagnose life threatening heart disease so as to decrease unnecessary hospital admissions and reduce patient cost.

The ultrasound contrast agents used in the study are currently being used to improve ultrasound image quality, according to the study, and FDA approval is pending for the use of these contrast agents to evaluate blood flow in the heart muscle.

Doctors evaluated 957 patients complaining of suspected heart chest pain by performing the MCE study. MCE allowed researchers to view the heart borders and evaluate the blood flow throughout the heart muscle.

More importantly, MCE allowed doctors to identify abnormal blood flow, which can be a sign of severe blockages in the coronary arteries. Results showed that by using MCE to evaluate patients presenting with suspected heart chest pain, 55% of the patients studied could have been discharged from the emergency department, avoiding admittance charges and costly follow-up testing. The patients who had the MCE study saved roughly $700, plus the inconvenience of hospital stays.

SVU an early detector

Another research report found that screening vascular ultrasound (SVU) is effective in identifying patients with cardiovascular disease before they show symptoms and become ill.

Dr. John Postley of Columbia University (New York) evaluated 398 patients, ages 33-79, using both Framingham Risk Score (FRS) and SVU. Of the 398 patients, SVU found 171 patients to have plaque build-up in the arteries of the neck and thigh. Of those 171 who were found to actually have plaque build-up, 25% of men and 35% of women were categorized as low risk by FRS.

SVU identified cardiovascular disease in these patients that FRS alone might have otherwise overlooked. The findings also confirm the importance of assessing plaque levels in both the thigh and neck veins since 20% of the 171 patients with plaque would have been missed if only plaque levels in the neck had been assessed.

“These findings suggest that even patients with low Framingham Risk Scores may have cardiovascular disease, as demonstrated by the presence of plaque build-up, and that SVU is an effective method to identify these patients,” said Postley. “This combination of technologies is wonderful news for the medical community as it will help identify people with clogged arteries before they even begin showing symptoms, allowing physicians to be more proactive in treatment.”

Obesity linked to LVH

An association between obesity and left ventricular hypertrophy (LVH), a condition that can potentially cause heart failure and rhythm problems, was found as a result of research released at the conference. That finding may improve the understanding of the effect of obesity on the heart.

“These results are another stake in the ground that supports healthy lifestyles for the benefit of heart protection,” said Dr. Movahed of the University of Arizona Server Heart Center (Tucson). “This gives us further evidence that maintaining a proportionate BMI [body mass index] could be beneficial for protection of heart function.”

Using a database of 17,261 heart ultrasounds, doctors evaluated the occurrence of LVH in relation to gender, valvular abnormalities, age, BMI and body surface area.

The heart ultrasounds allowed researchers to view a moving image of the heart to evaluate structure and function.

Results showed that narrowing of the aortic valve was the strongest predictor of LVH, followed by gender and BMI. Men have thicker hearts than women in general; however, obesity raises risk levels for the development of LVH in both genders even further as it causes the heart to work harder to pump blood.