Advanced Cardiovascular Sonographer: a proposal of the American Society of Echocardiography Advanced Practice Sonographer Task Force.

Echocardiographic examinations require a well-trained and competent sonographer to obtain proper anatomic and physiologic data to establish an accurate diagnosis for clinical decision-making and patient management. Although the formal education and training of cardiovascular sonographers are evolving, many entry-level and staff sonographers may not have sufficient practical or clinical knowledge of the necessary components of the echocardiographic study for the individual patient's clinical presentation. In many clinical settings, echocardiograms are read after the patient has left the laboratory. Thus, there is a role for a sonographer who can practice at an advanced level in a cardiovascular ultrasound laboratory to ensure a proper echocardiographic examination is performed on every patient. In this setting, an Advanced Cardiovascular Sonographer (ACS) would be able to review the indication for and quality of the examination. If additional images were needed, the ACS would assist the sonographer in obtaining these images, which would lead to the performance of a complete and fully diagnostic examination before the patient had left the echocardiography laboratory. In clinical practice, the quality of the examinations performed would improve, advancements in echocardiographic methods could be taught and incorporated into daily practice, and patients would be better served. The present report is a proposal from the American Society of Echocardiography Advanced Practice Task Force that identifies the potential of cardiac sonographers to achieve the ACS level.

Comparison of myocardial contrast echocardiography derived myocardial perfusion reserve with invasive determination of coronary flow reserve.

AIMS: Invasive measurements of coronary flow reserve (CFR) by Doppler flow wire are an established method for determining coronary blood flow physiology. Myocardial contrast echocardiography (MCE) is a potential non-invasive method for quantifying myocardial blood flow (MBF). However, few studies have compared MCE-derived myocardial perfusion reserve (MPR) with Doppler flow wire-derived CFR, measured simultaneously in human subjects. This study aimed to correlate MCE-derived MPR with Doppler flow wire-derived CFR. METHODS AND RESULTS: Ten patients with at least two angiographically normal coronary arteries underwent simultaneous invasive Doppler flow wire measurements and MCE imaging at rest and at peak hyperaemia. Hyperaemia was induced by intravenous adenosine infusion. Doppler-derived CFR was calculated as the ratio of hyperaemic to baseline average peak red blood cell velocity. MPR was calculated as the hyperaemic to baseline ratio of the following parameters: myocardial blood volume (MBV), myocardial microbubble velocity (MMV), and MBF. MCE was performed using real-time and triggered imaging with contrast infused intravenously by bolus and continuous methods. Regardless of whether the contrast was infused by bolus or continuous methods, Doppler flow wire-derived CFR had a stronger correlation with MPR derived by MBV (r=0.8, P=0.05) than with MPR derived by microbubble velocity (r=0.3, P>0.05) or MBF (r=0.4, P>0.05). Real-time imaging with continuous infusion provided better correlation with CFR than triggered imaging methods or bolus administration. CONCLUSION: Myocardial perfusion reserve derived by real-time infusion MBV measurements correlates with Doppler flow wire-derived CFR. Therefore, MPR may be a potential surrogate for Doppler flow wire-derived CFR in patients with angiographically normal coronary arteries.

American Society of Echocardiography Consensus Statement on the Clinical Applications of Ultrasonic Contrast Agents in Echocardiography.

UNLABELLED: ACCREDITATION STATEMENT: The American Society of Echocardiography (ASE) is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The ASE designates this educational activity for a maximum of 1 AMA PRA Category 1 Credit.trade mark Physicians should only claim credit commensurate with the extent of their participation in the activity. The American Registry of Diagnostic Medical Sonographers and Cardiovascular Credentialing International recognize the ASE's certificates and have agreed to honor the credit hours toward their registry requirements for sonographers. The ASE is committed to resolving all conflict-of-interest issues, and its mandate is to retain only those speakers with financial interests that can be reconciled with the goals and educational integrity of the educational program. Disclosure of faculty and commercial support sponsor relationships, if any, have been indicated. TARGET AUDIENCE: This activity is designed for all cardiovascular physicians, cardiac sonographers, and nurses with a primary interest and knowledge base in the field of echocardiography; in addition, residents, researchers, clinicians, sonographers, and other medical professionals having a specific interest in contrast echocardiography may be included. OBJECTIVES: Upon completing this activity, participants will be able to: 1. Demonstrate an increased knowledge of the applications for contrast echocardiography and their impact on cardiac diagnosis. 2. Differentiate the available ultrasound contrast agents and ultrasound equipment imaging features to optimize their use. 3. Recognize the indications, benefits, and safety of ultrasound contrast agents, acknowledging the recent labeling changes by the US Food and Drug Administration (FDA) regarding contrast agent use and safety information. 4. Identify specific patient populations that represent potential candidates for the use of contrast agents, to enable cost-effective clinical diagnosis. 5. Incorporate effective teamwork strategies for the implementation of contrast agents in the echocardiography laboratory and establish guidelines for contrast use. 6. Use contrast enhancement for endocardial border delineation and left ventricular opacification in rest and stress echocardiography and unique patient care environments in which echocardiographic image acquisition is frequently challenging, including intensive care units (ICUs) and emergency departments. 7. Effectively use contrast echocardiography for the diagnosis of intracardiac and extracardiac abnormalities, including the identification of complications of acute myocardial infarction. 8. Assess the common pitfalls in contrast imaging and use stepwise, guideline-based contrast equipment setup and contrast agent administration techniques to optimize image acquisition.

Serial changes in systolic and diastolic echocardiographic indices as predictors of outcome in patients with decreased left ventricular ejection fraction.

BACKGROUND: Echocardiographic estimation of left ventricular ejection fraction aids in predicting adverse outcomes in coronary artery disease. However, in patients with impaired left ventricular function, further risk stratification is difficult. METHODS: A 2 year retrospective review was performed to identify patients with ejection fraction < or=30%. Echocardiographic measures of systolic and diastolic function were independently performed offline. Outcome information, which included MI, stroke, or death, was obtained. The patient cohort identified those with follow-up having 1) a single echocardiogram and a subset 2) with an initial echocardiogram and a second echocardiogram at greater than one year follow-up. RESULTS: This study included 110 patients, ages 20-94. Mean follow-up time was 29+/-9 months. Ejection fraction did not predict cardiovascular events. LV mass predicted of mortality (p=0.03). Diastolic indexes of mitral inflow E wave was a significant predictor of outcome (p=0.05). Impaired diastolic filling grade 2, 3, or 4 showed a 76% event rate. Decreases in ejection fraction at follow-up were seen in those who had an event, with an average decrease in ejection fraction of 17% versus those who lived with no event of 1%. Changes in mitral inflow E wave and changes in E/A ratio were both significant predictors of outcome. CONCLUSIONS: These data indicate that echocardiographic measures of both systolic and diastolic function aid in risk stratifying patients with decreased ejection fraction. The changed detected in serial echocardiographic information may be important in treatment and secondary prevention of future events.

Efficacy of atropine as a chronotropic agent in heart transplant patients undergoing dobutamine stress echocardiography.

BACKGROUND: After heart transplant (HTX), the heart is completely denervated. While sympathetic reinnervation is likely to occur, there is conflicting evidence regarding parasympathetic reinnervation. Accordingly, it is unclear if atropine is efficacious as a chronotropic agent in HTX patients undergoing dobutamine stress echocardiography (DSE), since cholinergic cardiac stimulation is required for atropine to exert its effect. The purpose of this study was to demonstrate that atropine can sufficiently increase the heart rate (HR) in HTX patients undergoing DSE. METHODS: A retrospective review was performed on 68 HTX patients who underwent DSE as part of their routine annual HTX follow-ups. Dobutamine was administered in the standard fashion of 10, 20, 30, 40, 50 mcg/kg per minute with blood pressure and electrocardiographic monitoring. If target HR was not attained, atropine was administered to aid in achieving 85% of maximum age-predicted HR. RESULTS: Mean patient age was 58 +/- 10 years. Mean period since transplant was 9 +/- 4 years. Forty-seven (69%) patients received dobutamine only, and 21 (31%) required additional atropine to reach target HR. Of the 21 patients who received atropine, 10 (48%) reached target HR. Neither time from transplant, age, gender, resting HR, medications, nor atherosclerotic risk factors predicted responsiveness to atropine. Those responding to dobutamine had a significantly greater resting HR than those receiving additional atropine. CONCLUSIONS: The adjunctive use of atropine in HTX patients during DSE aids in reaching 85% of maximum predicted HR in some patients. Furthermore, resting HR may predict the additional need of atropine during DSE.

Improved visualization of aortic intima-media thickening with the use of perflutren lipid microspheres.

BACKGROUND: Transesophageal echocardiography (TEE) has been used to diagnose atherosclerotic disease for patients who present with systemic embolic events. The primary aim of this study was to assess the supplemental value of echocardiographic contrast to standard TEE in identifying the aortic intima-medial thickness. METHODS: An aorta phantom was used to validate the accuracy of border delineation with and without contrast during TEE imaging. In all, 44 patients underwent TEE imaging of the thoracic aorta with a subsequent administration of a 0.3-mL bolus of perflutren lipid microspheres (Definity). Precontrast and postcontrast images were analyzed semiquantitatively for border delineation and quantitatively for intima-medial thickness and cross-sectional area. RESULTS: Wall thickness in the aortic phantom model with contrast was smaller, more accurate, and more reproducible to the true measurement. The clinical studies reflected similar results with average contrast intima-medial thickness measured at 0.15 +/- 0.08 cm and noncontrast at 0.18 +/- 0.08 cm (P < .01). The lateral wall showed the greatest improvement with a score of 1.23 increasing to an average of 1.82 (P < .001) with contrast. The medial, anterior, and posterior walls improved to an average 1.98, 1.39, and 2.0, respectively (P = .01). CONCLUSIONS: Contrast agents provide better aortic intima-media enhancement during TEE.

Clinical application of harmonic power Doppler imaging in the assessment of myocardial perfusion by contrast echocardiography.

Myocardial contrast echocardiography has moved from the research laboratory to clinical echocardiography. As with any emerging technology, background information and understanding the process of image acquisition will help to integrate the technology into everyday practice. Harmonic power Doppler imaging (HPDI) is a high-power, triggered imaging modality used to assess myocardial perfusion. Contrast agents used in echocardiography provide microvascular tracers that enable HPDI to accurately visualize myocardial blood flow. This article aims to provide direction in the clinical performance of myocardial contrast echocardiography by providing background in the theory and physics of HPDI and a guide to the technical acquisition of images and recognition of artifacts that arise during HPDI.

The research grant process: a reference guide for cardiovascular sonographers.

Opportunities for sonographer-initiated research have increased during the past decade. Although research has traditionally been viewed as a nonclinical activity, funding is available for clinical problems. This article aims to increase sonographer awareness of this unique opportunity, encourage the submission of grant proposals, and enhance the understanding of the grant writing process. This review discusses the procedures involved in planning a research project while describing the structure of the research grant proposal including specific aims, background, preliminary studies, methods, potential limitations, significance, budget, and references.

Tertiary care improves the chance for vaginal delivery in women with preeclampsia.

OBJECTIVE: The purpose of this study was to determine whether the level of hospital care affects cesarean delivery rates for women with preeclampsia. STUDY DESIGN: We conducted a population-based cohort study using Missouri birth certificate data for 1993 through 1999. Logistic regression was used to analyze data from 13,646 nulliparous women with preeclampsia who were delivered of singleton live births. RESULTS: After adjustment was made for gestational age and birth weight, the data showed that women with preeclampsia at primary and secondary hospitals were more likely to be delivered by cesarean delivery (odds ratio, 1.37; 95% CI, 1.24,1.51; and odds ratio, 1.16; 95% CI, 1.07,1.26, respectively) than at tertiary hospitals. For women who were delivered at >or=37 weeks of gestation, cesarean delivery rates were 38.0%, 33.7%, and 30.0% for primary, secondary, and tertiary hospitals, respectively. Dysfunctional labor, cephalopelvic disproportion, and fetal distress were more commonly noted at primary and secondary hospitals (P<.001). CONCLUSION: Levels of expertise and staffing at tertiary hospitals may allow greater attempts and success with vaginal delivery among women with preeclampsia compared with primary or secondary hospitals.