Acute Mortality in Hospitalized Patients Undergoing Echocardiography With and Without an Ultrasound Contrast Agent

Perfusion imaging metrics after acute traumatic spinal cord injury are associated with injury severity in rats and humans

Traumatic spinal cord injury (tSCI) causes an immediate loss of neurological function, and the prediction of recovery is difficult in the acute phase. In this study, we used contrast-enhanced ultrasound imaging to quantify intraspinal vascular disruption acutely after tSCI. In a rodent thoracic tSCI model, contrast-enhanced ultrasound revealed a perfusion area deficit that was positively correlated with injury severity and negatively correlated with hindlimb locomotor function at 8 weeks after injury. The spinal perfusion index was calculated by normalizing the contrast inflow at the injury center to the contrast inflow in the injury periphery. The spinal perfusion index decreased with increasing injury severity and positively correlated with hindlimb locomotor function at 8 weeks after injury. The feasibility of intraoperative contrast-enhanced ultrasound imaging was further tested in a cohort of 27 patients with acute tSCI of varying severity and including both motor-complete and motor-incomplete tSCIs. Both the perfusion area deficit and spinal perfusion index were different between motor-complete and motor-incomplete patients. Moreover, the perfusion area deficit and spinal perfusion index correlated with the injury severity at intake and exhibited a correlation with extent of functional recovery at 6 months. Our data suggest that intraoperative contrast-enhanced, ultrasound-derived metrics are correlated with injury severity and chronic functional outcome after tSCI. Larger clinical studies are required to better assess the reliability of the proposed contrast-enhanced ultrasound biomarkers and their prognostic capacity.

Incidence of Severe Adverse Drug Reactions to Ultrasound Enhancement Agents in a Contemporary Echocardiography Practice

OBJECTIVES

Prior data indicate a very rare risk of serious adverse drug reaction (ADR) to ultrasound enhancement agents (UEAs). We sought to evaluate the frequency of ADR to UEA administration in contemporary practice.

METHODS

We retrospectively reviewed 4 US health systems to characterize the frequency and severity of ADR to UEA. Adverse drug reactions were considered severe when cardiopulmonary involvement was present and critical when there was loss of consciousness, loss of pulse, or ST-segment elevation. Rates of isolated back pain and headache were derived from the Mayo Clinic Rochester stress echocardiography database where systematic prospective reporting of ADR was performed.

RESULTS

Among 26,539 Definity and 11,579 Lumason administrations in the Mayo Clinic Rochester stress echocardiography database, isolated back pain or headache was more frequent with Definity (0.49% vs 0.04%, P < .0001) but less common with Definity infusion versus bolus (0.08% vs 0.53%, P = .007). Among all sites there were 201,834 Definity and 84,943 Lumason administrations. Severe and critical ADR were more frequent with Lumason than with Definity (0.0848% vs 0.0114% and 0.0330% vs 0.0010%, respectively; P < .001 for each). Among the 3 health systems with >2,000 Lumason administrations, the frequency of severe ADR with Lumason ranged from 0.0755% to 0.1093% and the frequency of critical ADR ranged from 0.0293% to 0.0525%. Severe ADR rates with Definity were stable over time but increased in more recent years with Lumason (P = .02). Patients with an ADR to Lumason since the beginning of 2021 were more likely to have received a COVID-19 vaccination compared with matched controls (88% vs 75%; P = .05) and more likely to have received Moderna than Pfizer-Biotech (71% vs 26%, P < .001).

CONCLUSION

Severe and critical ADR, while rare, were more frequent with Lumason, and the frequency has increased in more recent years. Additional work is needed to better understand factors, including associations with recently developed mRNA vaccines, which may be contributing to the increased rates of ADR to UEA since 2021.

Efficacy and safety of use of ultrasound enhancing agent in patients hospitalized with COVID-19

PURPOSE

The efficacy and safety of ultrasound enhancing agent (UEA) was unknown in the COVID-19 hospitalized patients. We set out to establish the utility of UEA and its safety profile.

METHODS

A retrospective observational study of prospectively assessed hospitalized patients referred for transthoracic echocardiography (TTE) for suspected cardiac pathology due to COVID-19. The indications and subsequent ability to answer the indications for all TTE were reviewed, as well as impact on diagnosis and management. UEA safety was considered through 48 h mortality.

RESULTS

From a total of 364 patients (mean age 64.8yrs, 64% males) hospitalized with COVID-19 with TTE requested, an indication could be identified in 363, and 61 required administration of UEA. Standard TTE was able to answer the original indication in 275 (75.8%) patients. This was increased to 322 (88.7%) patients, a relative increase of 17.1%, with the use of UEA (p < 0.001). There was subsequent change in diagnosis in 22 out of 61 (36%) patients receiving UEA and change in management in 13 out of 61 (21.3%). There was no significant increase in 48 h (p = 0.14) mortality with UEA use. The patient population of TTE with UEA versus TTE without UEA differed in having a higher incidence of left ventricular systolic dysfunction, right ventricular dilatation, and self-defined white ethnicity.

CONCLUSION

The use of UEA in COVID-19 hospitalized patients, including those who were critically ill, provided incremental information when compared to TTE without UEA resulting in both changes in diagnosis and management plan and appears to be safe.

Safety of Lumason® (SonoVue®) in special populations and critically ill patients

Evidence for the safe use of Lumason® (SonoVue®), an ultrasound enhancing agent (UEA), in special patient populations is critical to enable healthcare professionals to make informed decisions concerning its use in such patients. Herein, we provide insight on the safety and tolerability of Lumason® in special patient populations. Findings are presented from clinical pharmacology studies conducted in patients with compromised cardiopulmonary conditions, from a retrospective study performed in critically ill patients, and from post-marketing surveillance data from over 20 years of market use of Lumason® (SonoVue®). No detrimental effects of Lumason® on cardiac electrophysiology were observed in patients with coronary artery disease (CAD), and no significant effects on pulmonary hemodynamics were noted in patients with pulmonary hypertension or congestive heart failure. Similarly, no effects on several assessments of pulmonary function (e.g., FVC) were observed in patients with chronic obstructive pulmonary disease (COPD), and no clinically meaningful changes in O2 saturation or other safety parameters were observed after administration of Lumason® to patients with diffuse interstitial pulmonary fibrosis (DIPF). The retrospective study of critically ill patients revealed no significant difference for in-hospital mortality between patients administered Lumason® for echocardiography versus those who had undergone echocardiography without contrast agent. Post-marketing surveillance revealed very low reporting rates (RR) for non-serious and serious adverse events and that serious hypersensitivity reactions were rare. These findings confirm that Lumason® is a safe and well tolerated UEA for use in special populations and critically ill patients.

CEUS cardiac exam protocols International Contrast Ultrasound Society (ICUS) recommendations

The present CEUS Cardiac Exam Protocols represent the first effort to promulgate a standard set of protocols for optimal administration of ultrasound enhancing agents (UEAs) in echocardiography, based on more than two decades of experience in the use of UEAs for cardiac imaging. The protocols reflect current clinical CEUS practice in many modern echocardiography laboratories throughout the world. Specific attention is given to preparation and dosing of three UEAs that have been approved by the United States Food and Drug Administration (FDA) and additional regulatory bodies in Europe, the Americas and Asia–Pacific. Consistent with professional society guidelines (J Am Soc Echocardiogr 31:241–274, 2018; J Am Soc Echocardiogr 27:797–810, 2014; Eur Heart J Cardiovasc Imaging 18:1205, 2017), these protocols cover unapproved “off-label” uses of UEAs—including stress echocardiography and myocardial perfusion imaging—in addition to approved uses. Accordingly, these protocols may differ from information provided in product labels, which are generally based on studies performed prior to product approval and may not always reflect state of the art clinical practice or guidelines.

Contrast Ultrasound, Sonothrombolysis and Sonoperfusion in Cardiovascular Disease: Shifting to Theragnostic Clinical Trials

Contrast ultrasound has a variety of applications in cardiovascular medicine, both in diagnosing cardiovascular disease as well as providing prognostic information. Visualization of intravascular contrast microbubbles is based on acoustic cavitation, the characteristic oscillation that results in changes in the reflected ultrasound waves. At high power, this acoustic response generates sufficient shear that is capable of enhancing endothelium-dependent perfusion in atherothrombotic cardiovascular disease (sonoperfusion). The oscillation and collapse of microbubbles in response to ultrasound also induces microstreaming and jetting that can fragment thrombus (sonothrombolysis). Several preclinical studies have focused on identifying optimal diagnostic ultrasound settings and treatment regimens. Clinical trials have been performed in acute myocardial infarction, stroke, and peripheral arterial disease often with improved outcome. In the coming years, results of ongoing clinical trials along with innovation and improvements in sonothrombolysis and sonoperfusion will determine whether this theragnostic technique will become a valuable addition to reperfusion therapy.

Safety of SF6(SonoVue®) Contrast Agent on Pharmacological Stress Echocardiogram

Fundamento

Em 2007, a Food and Drug Administration (FDA) determinou revisões sobre segurança dos agentes de contraste ecocardiográfico (ACE) disponíveis no mercado após relatos de mortes. Ao longo desses anos, diversos estudos comprovaram a segurança dos ACE, porém com poucos estudos relacionados ao SonoVue^®.

Objetivos

Avaliar a segurança do SonoVue^® durante o ecocardiograma sob estresse farmacológico (EEF) por meio da análise da incidência de reações alérgicas e da comparação entre os grupos quanto ao surgimento de arritmia, efeitos colaterais menores e eventos adversos.

Métodos

Estudo observacional, prospectivo, no qual 2.346 pacientes foram submetidos ao EEF e divididos em dois grupos: grupo 1 com ACE (n=1.099) e grupo 2 sem ACE (n=1.247). Os pacientes foram avaliados durante o EEF – 24 horas e 30 dias. Foi definido p significativo quando <0,05.

Resultados

O grupo 1 apresentou efeitos colaterais mais leves, como cefaleia (5/0,5% vs. 19/1,5%, p=0,012) e hipertensão reativa (3/0,3% vs . 19/1,5%, p=0,002), menos arritmias como extrassístoles ventriculares (180/16,4% vs . 247/19,8%, p=0,032) e taquicardia paroxística supraventricular (2/0,2% vs . 15/1,2%, p=0,003), assim como nenhum evento adverso como infarto agudo do miocárdio (IAM) e óbito. No grupo 2, um paciente apresentou IAM <24h (1/01%) e dois óbitos <30 dias (2/0,1%). Urticária relacionada ao SonoVue^® foi observada em 3 (0,3%) pacientes sem reação anafilática.

Conclusão

SonoVue^® demonstrou segurança durante o EEF, não sendo observados morte, IAM ou reação anafilática. Observou-se menor incidência de efeitos colaterais mais leves e arritmias no grupo que utilizou o ACE, assim como baixa incidência de reações alérgicas leves.

Effects of Copaiba Oil in Peripheral Markers of Oxidative Stress in a Model of Cor Pulmonale in Rats

Fundamento

Até o presente momento, os efeitos sistêmicos do óleo de copaíba jamais foram documentados no Cor pulmonale induzido por monocrotalina.

Objetivos

Investigar os efeitos do óleo de copaíba nos marcadores periféricos de stress oxidativo em ratos com Cor pulmonale.

Métodos

Ratos Wistar machos (170±20g, n=7/grupo) foram divididos em quatro grupos: controle (CO), monocrotalina (MCT), óleo de copaíba (O), e monocrotalina + óleo de copaíba (MCT-O). Foi administrada a MCT (60 mg/kg i.p.) e, depois de uma semana, foi iniciado o tratamento com óleo de copaíba (400 mg/kg/day-gavagem-14 dias). Foi realizado o ecocardiograma e, depois disso, foi coletado sangue do tronco para a realização de avaliações de stress oxidativo. Análise estatística: ANOVA de duas vias com teste Student-Newman-Keuls post hoc. P-valores <0,05 foram considerados significativos.

Resultados

O óleo de copaíba reduziu a resistência vascular pulmonar e a hipertrofia do ventrículo direito (VD) hipertrofia (Índice de Fulton (mg/mg)): MCT-O= 0,39±0,03; MCT= 0,49±0,01), e função sistólica melhorada (fração de encurtamento do VD, %) no grupo MCT-O (17,8±8,2) em comparação com o grupo de MCT (9,4±3,1; p<0,05). Além disso, no grupo MCT-O, espécies reativas do oxigênio e os níveis de carbonila foram reduzidos, e os parâmetros antioxidantes aumentaram no sangue periférico (p <0,05).

Conclusões

Os resultados deste estudo sugerem que o óleo de copaíba tem um efeito antioxidante sistêmico interessante, que se reflete na melhoria da função e na morfometria do VD nesse modelo de Cor pulmonale . A atenuação do Cor pulmonale promovida pelo óleo de copaíba coincidiu com uma redução no stress oxidativo sistêmico.

Experiência inicial com ultrassom Doppler com contraste por microbolhas em adição ao ultrassom Doppler convencional para seguimento de correção endovascular de aneurisma de aorta abdominal

Background

Microbubble contrast enhanced ultrasound (CEUS) is an accurate diagnostic method for follow-up after endovascular abdominal aortic aneurysm repair (EVAR) that has been well-established in international studies. However, there are no Brazilian studies that focus on this follow-up method.

Objectives

The objective of this study was to report initial experience with CEUS at a tertiary hospital, comparing the findings of CEUS with those of conventional Doppler ultrasound (DUS), with the aim of determining whether addition of contrast to the standard ultrasonographic control protocol resulted in different findings.

Methods

From 2015 to 2017, 21 patients in follow-up after EVAR underwent DUS followed by CEUS. The findings of these examinations were analyzed in terms of identification of complications and their capacity to identify the origin of endoleaks.

Results

There was evidence of complications in 10 of the 21 cases examined: seven patients exhibited endoleaks (33.3%); two patients exhibited stenosis of a branch of the endograft (9.52%); and one patient exhibited a dissection involving the external iliac artery (4.76%). In the 21 patients assessed, combined use of both methods identified 10 cases of post-EVAR complications. In six of the seven cases of endoleaks (85.71%), use of the methods in combination was capable of identifying the origin of endoleakage. DUS alone failed to identify endoleaks in two cases (28.5%) and identified doubtful findings in another two cases (28.5%), in which diagnostic definition was achieved after employing CEUS.

Conclusions

CEUS is a technique that is easy to perform and provides additional support for follow-up of infrarenal EVAR.

Review of ultrasound contrast agents in current clinical practice with special focus on DEFINITY® in cardiac imaging

Echocardiography is the most widely used noninvasive modality to evaluate the structure and function of the cardiac muscle in daily practice. However, up to 15-20% of echocardiograms are considered suboptimal. To enable accurate assessment of cardiac function and wall motion abnormality, the use of ultrasound microbubble contrast has shown substantial benefits in cases of salvaging nondiagnostic studies and enhancing the diagnostic accuracy in daily practice. DEFINITY^® is a perflutren based, lipid shelled microbubble contrast agent, which is US FDA approved for left ventricular opacification. The basis of ultrasound microbubbles, its development, and the clinical role of DEFINITY (characteristics, indications and case examples, side effect profile and existing evidence) is the subject of discussion in this review.

General principles and overview of vascular contrast-enhanced ultrasonography

Ultrasonography (US) is the first-line modality for the evaluation of vascular pathology. Although well-established for many diseases, US has inherent limitations that can occasionally hinder an accurate diagnosis. The value of US was improved by the introduction of microbubbles as ultrasonographic contrast agents (UCAs) and the emergence of contrast-enhanced ultrasonography (CEUS), following the introduction of second-generation UCAs and the emergence of modern contrast-specific techniques. CEUS offers valuable information about vascular disease, both on a macrovascular and a microvascular level, with well-established applications for carotid disease, post-interventional follow-up of abdominal aortic aneurysms, and the assessment of portal vein thrombosis. The purpose of this review is to discuss the principles of CEUS and to present an overview of its vascular applications.

Reverse engineering the ultrasound contrast agent

In this review, a brief history and current state-of-the-art is given to stimulate the rational design of new microbubbles through the reverse engineering of current ultrasound contrast agents (UCAs). It is shown that an effective microbubble should be biocompatible, echogenic and stable. Physical mechanisms and engineering calculations have been provided to illustrate these properties and how they can be achieved. The reverse-engineering design paradigm is applied to study current FDA-approved and commercially available UCAs. Given the sophistication of microbubble designs reported in the literature, rapid development and adoption of ultrasound device hardware and techniques, and the growing number of revolutionary biomedical applications moving toward the clinic, the field of Microbubble Engineering is fertile for breakthroughs in next-generation UCA technology. It is up to current and future microbubble engineers and clinicians to push forward with regulatory approval and clinical adoption of advanced UCA technologies in the years to come.

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This literature review in devoted to the potential of application of contrast-enhanced echocardiography (CEE) for assessment of structure and function of left cardiac chambers. It contains based on current recommendations discussion of main indications for CEE and analysis of its possibilities in evaluation of perfusion of the left ventricular myocardium, detection of myocardial ischemia, and assessment of myocardial viability. Data on CEE safety and possible side effects associated with the use of ultrasound contrasts are also presented.

Contrast-enhanced ultrasound (CEUS) nephrostogram: utility and accuracy as an alternative to fluoroscopic imaging of the urinary tract

AIM

To establish the feasibility and accuracy of contrast-enhanced ultrasound (CEUS) nephrostogram in comparison to the reference standard, fluoroscopic nephrostogram, in providing alternative imaging of the urinary tract post-nephrostomy insertion.

MATERIALS AND METHODS

This prospective study was approved by the institutional and national ethics committee. All patients for whom a fluoroscopic nephrostogram was requested were included. Fluoroscopic and CEUS nephrostograms were performed within 24 hours. Image analysis (nephrostomy position, opacification of pelvicalyceal system, ureter, and bladder) was performed by two reviewers, and the diagnostic accuracy of the CEUS nephrostograms was compared to fluoroscopic nephrostograms.

RESULTS

Sixty-two nephrostograms were performed in 48 patients from June 2011 to April 2016, (male: 25/48, 52.1%; mean age 65 years, range 28-90 years). Indications for nephrostomy were: malignancy (29/62; 46.8%), benign ureteric stricture (14/62; 22.6%), urinary diversion (8/62; 12.9%), renal calculus (5/62; 8.1%), haematoma (3/62; 4.8%) or pelvi-ureteric junction obstruction (3/62; 4.8%). Two nephrostomies were identified as displaced by both techniques. The pelvicalyceal system was visualised in 60/60 (100%) examinations in both fluoroscopic and CEUS nephrostograms. The entire ureter was visualised in 30/60 (50%) with CEUS compared to 32/60 (53.3%) fluoroscopically. The distal ureter was the least well-visualised segment for both techniques with no significant difference (p=0.815). Both CEUS and fluoroscopy could be used to correctly identify complications including entero-ureteric fistula or urine leak. Fluoroscopic nephrostogram demonstrated drainage into the bladder in 33/60 (55%), CEUS confirmed drainage in 34/60 (56.7%) cases (p=0.317).

CONCLUSIONS

CEUS nephrostogram can determine the correct positioning of a nephrostomy and assess drainage into the bladder with statistically comparable results to fluoroscopy.

Clinical practice of contrast echocardiography: recommendation by the European Association of Cardiovascular Imaging (EACVI) 2017

Contrast echocardiography is widely used in cardiology. It is applied to improve image quality, reader confidence and reproducibility both for assessing left ventricular (LV) structure and function at rest and for assessing global and regional function in stress echocardiography. The use of contrast in echocardiography has now extended beyond cardiac structure and function assessment to evaluation of perfusion both of the myocardium and of the intracardiac structures. Safety of contrast agents have now been addressed in large patient population and these studies clearly established its excellent safety profile. This document, based on clinical trials, randomized and multicentre studies and published clinical experience, has established clear recommendations for the use of contrast in various clinical conditions with evidence-based protocols.

Contrast-Enhanced Ultrasound

Contrast-enhanced ultrasound imaging is a recently approved technique in the United States that uses a specific contrast agent, namely, microbubbles, consisting mainly of a gas core and a stabilized biological shell. These compounds allow for the visualization of small vascular beds and improve characterization of anatomic structures and lesions. They have a relatively safe profile and are primarily excreted through the lungs.

Imaging with ultrasound contrast agents: current status and future

Microbubble ultrasound contrast agents (UCAs) were recently approved by the Food and Drug administration for non-cardiac imaging. The physical principles of UCAs, methods of administration, dosage, adverse effects, and imaging techniques both current and future are described. UCAs consist of microbubbles in suspension which strongly interact with the ultrasound beam and are readily detectable by ultrasound imaging systems. They are confined to the blood pool when administered intravenously, unlike iodinated and gadolinium contrast agents. UCAs have a proven safety record based on over two decades of use, during which they have been used in echocardiography in the U.S. and for non-cardiac imaging in the rest of the world. Adverse effects are less common with UCAs than CT/MR contrast agents. Compared to CT and MR, contrast-enhanced ultrasound has the advantages of real-time imaging, portability, and reduced susceptibility to metal and motion artifact. UCAs are not nephrotoxic and can be used in renal failure. High acoustic amplitudes can cause microbubbles to fragment in a manner that can result in short-term increases in capillary permeability or capillary rupture. These bioeffects can be beneficial and have been used to enhance drug delivery under appropriate conditions. Imaging with a mechanical index of < 0.4 preserves the microbubbles and is not typically associated with substantial bioeffects. Molecularly targeted ultrasound contrast agents are created by conjugating the microbubble shell with a peptide, antibody, or other ligand designed to target an endothelial biomarker associated with tumor angiogenesis or inflammation. These microbubbles then accumulate in the microvasculature at target sites where they can be imaged. Ultrasound contrast agents are a valuable addition to the diagnostic imaging toolkit. They will facilitate cross-sectional abdominal imaging in situations where contrast-enhanced CT and MR are contraindicated or impractical.

How to perform Contrast-Enhanced Ultrasound (CEUS)

"How to perform contrast-enhanced ultrasound (CEUS)" provides general advice on the use of ultrasound contrast agents (UCAs) for clinical decision-making and reviews technical parameters for optimal CEUS performance. CEUS techniques vary between centers, therefore, experts from EFSUMB, WFUMB and from the CEUS LI-RADS working group created a discussion forum to standardize the CEUS examination technique according to published evidence and best personal experience. The goal is to standardise the use and administration of UCAs to facilitate correct diagnoses and ultimately to improve the management and outcomes of patients.

Anaphylactic shock with an ultrasound contrast agent

Echo contrast agents, such as SonoVue^®, (Bracco, Milan, Italy) are often used to enhance diagnosis. Although their use is safe, some rare side effects could be severe or even fatal. We are reporting a case of severe systemic allergic reaction after infusion of SonoVue^®. After a brief review of the literature, the aim of this paper is to draw attention to this risk and recall the safety instructions coming with the use of ultrasound contrast agents.

Quantitative Analysis of Hepatic Microcirculation in Rabbits After Liver Ischemia-Reperfusion Injury Using Contrast-Enhanced Ultrasound

Previous studies have shown that contrast-enhanced ultrasound (CEUS) can be used quantitatively to analyze microcirculation blood perfusion in hepatocellular carcinoma patients. However, limited data have described the application of CEUS in hepatic microcirculation after liver ischemic-reperfusion injury (IRI). The purpose of this study was to explore the use of CEUS quantitatively to assess liver microcirculation after liver IRI. We randomly sorted 45 New Zealand rabbits into 3 groups (15 in each). Group A was a control group in which the rabbits underwent laparotomy alone. In groups B and C, hepatic blood was blocked for 30 min. Simultaneously, rabbits in group C underwent left lateral lobe resection. After 30 min of ischemia, CEUS was conducted after 0 h, 1 h, 6 h and 24 h of reperfusion in the 3 groups. Time-intensity curves (TICs) for CEUS were constructed and quantitative parameters (maximum intensity [IMAX], rise time [RT], time to peak [TTP] and mean transit time [mTT]) were obtained. In addition, serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were computed to estimate liver function before the operation and at 0 h, 1 h, 6 h and 24 h after reperfusion, respectively. Pathologic changes in the liver after reperfusion were also observed. Simultaneously, the correlations between serum transaminase and a variety of quantitative analysis parameters were analyzed. In groups B and C, the IMAX value decreased; whereas RT, TTP, mTT and serum ALT and AST levels increased significantly in comparison with those in group A after 0 h and 1 h of reperfusion. The pathology revealed that erythrocytes were destroyed and microcirculation was disturbed. Then, at 6 h of reperfusion, the IMAX continued to decrease. Additionally, the levels of RT, TTP, mTT and serum ALT and AST increased in comparison with those at 1 h of reperfusion. The pathologic analysis revealed inflammatory cell aggregation and leukocyte infiltration. After 24 h of reperfusion, the IMAX was reduced in comparison with that of the 6-h group. The levels of RT, TTP, mTT and serum ALT and serum AST were increased in comparison with that of the 6-h group. These findings were in accordance with the pathologic analysis. In addition, serum transaminase had a negative correlation with IMAX (p < 0.001) and a positive correlation with RT, TTP and mTT (all p < 0.001). So, in conclusion, the quantitative analysis of CEUS can be used to assess hepatic microcirculation after liver IRI.

Safety With Echocardiographic Contrast Agents

In October 2007, the Food and Drug Administration mandated significant revisions to product labeling for the commercially available echocardiographic contrast agents (ECA) Definity and Optison after spontaneous healthcare provider reports of 4 patient deaths and ≈190 severe cardiopulmonary reactions occurring in close temporal relationship to ECA administration. Since then, multiple large ECA safety studies have been published and have included outpatients, hospitalized patients (including the critically ill), patients undergoing stress echocardiography, and patients with pulmonary hypertension. In addition, the Food and Drug Administration has convened 2 Advisory Committee meetings and the product labels for Optison and Definity have been substantially revised with a softening of safety restrictions. In this review, we will address the safety of ECA use in patients with serious cardiopulmonary conditions, patients with intracardiac shunts, and special patient populations including pulmonary hypertension, pediatrics, and pregnancy. In addition, we will discuss the confounding role of pseudocomplication in attribution of adverse events during diagnostic testing, the current status of the ECA Black Box Warning, and recommended safety precautions during ECA administration.

Contrast-enhanced US-guided Interventions: Improving Success Rate and Avoiding Complications Using US Contrast Agents

Ultrasonography (US) is an established modality for intervention. The introduction of microbubble US contrast agents (UCAs) has the potential to further improve US imaging for intervention. According to licensing, UCAs are currently approved for clinical use in restricted situations, but many additional indications have become accepted as having clinical value. The use of UCAs has been shown to be safe, and there is no risk of renal toxic effects, unlike with iodinated or gadolinium contrast medium. Broadly speaking, UCAs can be injected into the bloodstream (intravascular use) or instilled into almost any accessible body cavity (endocavitary use), either in isolation or synchronously. In microvascular applications, contrast-enhanced US (CEUS) enhances delineation of necrotic areas and the vascularized target to improve real-time targeting. The ability of CEUS to allow true assessment of vascularity has also been used in follow-up of devascularizing intervention. In macrovascular applications, real-time angiographic images can be obtained with CEUS without nephrotoxic effects or radiation. In endocavitary applications, CEUS can achieve imaging similar to that of iodinated contrast medium-based fluoroscopy; follow-up to intervention (eg, tubography and nephrostography) can be performed at the bedside, which may be advantageous. The use of UCAs is a natural progression in US-guided intervention. The aim of this article is to describe the indications, contraindications, and techniques of using UCAs as an adjunctive tool for US-guided interventional procedures to facilitate effective treatment, improve complication management, and increase the overall success of interventional procedures. Online supplemental material is available for this article. ^©RSNA, 2016.

Safety of Perflutren Ultrasound Contrast Agents: A Disproportionality Analysis of the US FAERS Database

INTRODUCTION

Perflutren microbubble/microsphere ultrasound contrast agents have a black-box warning based on case reports of serious cardiopulmonary events. There have been several subsequent observational safety studies. Large spontaneous reporting databases may help detect/refine signals of rare adverse events that elude other data sources/study designs.

OBJECTIVE

The objective of this study was to supplement existing knowledge of the reported safety of perflutren using statistical analysis of spontaneous reports.

METHODS

We analyzed information from the US Food and Drug Administration Adverse Event Reporting System using a disproportionality analysis. Analysis of overall reporting for perflutren was supplemented by subset (age, indication) analysis. A signal of disproportionate reporting (SDR) was defined as EB05 >2.

RESULTS

Overall, 18/380 Preferred Terms and 1/83 Standardized Medical Queries had SDRs. Most were small (EB05 = 2-4). Back pain and flank pain were the largest SDRs followed by events compatible with signs/symptoms of hypersensitivity. The general pattern of SDRs in the subset analysis was consistent with the overall analysis. Almost all events with SDRs were literally or conceptually labeled. Except for chest pain (higher in the age <65 years subgroup) and back pain (higher in the age ≥65 years subgroup), there were no statistically significant differences between age subsets. Except for the Preferred Terms Pruritus and Urticaria and the narrow Standardized Medical Queries Ventricular tachyarrhythmia, Angioedema, Oropharyngeal allergic conditions, and Hypersensitivity (higher in the stress test subgroup), there were no statistically significant reporting differences between indication subsets. There were no SDRs associated with the major cardiovascular events of death, myocardial infarction/ischemia, angina, arrhythmias, or convulsions in any analysis.

CONCLUSIONS

Our combined signal detection/evaluation analysis did not identify SDRs of novel adverse events or major cardiovascular events associated with perflutren ultrasound contrast agents. The negative results for major cardiovascular events extend previous signal evaluation exercises supporting the relative cardiovascular safety of these agents.

Intradermal microbubbles and contrast-enhanced ultrasound (CEUS) is a feasible approach for sentinel lymph node identification in early-stage breast cancer

BACKGROUND

Microbubbles and contrast-enhanced ultrasound (CEUS) is a new technique for locating sentinel lymph node (SLN). The aim of this study is to explore the feasibility of SLNs tracing by CEUS using microbubbles in breast cancer patients and the value of enhancing patterns in diagnosing lymph nodes metastases.

METHODS

A clinical trial was registered (trial registration: ChiCTR-DDT-13003778). One hundred and one consecutive consenting patients with breast cancer undergoing SLN biopsy were enrolled. Before the surgery, microbubble was injected periareolarly. Lymphatic drainage pathway was detected by CEUS, and guidewire was deployed to locate the SLN before the operation. Blue dye was also used to help in tracing sentinel lymph node during the operation. The identification rate and the accuracy rate were recorded. Enhancing patterns of lymph nodes were recorded and compared with the pathological diagnosis.

RESULTS

Of the 101 cases, SLNs in 99 cases were successfully identified by at least one tracer, including 98 cases identified by CEUS and 97 cases by blue dye. There was no significant difference between the two methods (P = 0.705). Guidewires were deployed successfully in all 98 cases, and the localized SLNs were all isolated successfully in the following operations. The status of SLNs isolated by CEUS was completely identical to that of the whole axillary lymph node while 7.1 % cases were misdiagnosed as negative by blue dye method. The sensitivity of predicting SLNs metastases by CEUS enhancing pattern was 81.8 %, the specificity was 86.2 %, and the positive and negative predictive values were 75.0 and 90.3 %, respectively.

CONCLUSIONS

Microbubbles and CEUS are feasible approaches for SLN identification. The enhancing patterns on CEUS may be helpful to recognize the metastasizing SLNs. This novel method may be a promising technique for the clinical application.

Prompt Recognition of Left Ventricular Free-Wall Rupture Aided by the Use of Contrast Echocardiography

In the modern period of reperfusion, left ventricular free-wall rupture occurs in less than 1% of myocardial infarctions. Typically, acute left ventricular free-wall rupture leads to sudden death from immediate cardiac tamponade. We present the case of a 59-year-old woman who sustained a posterior-wall myocardial infarction and subsequent cardiac arrest with pulseless electrical activity. A bedside transthoracic echocardiogram showed pericardial effusion with cardiac tamponade. Emergency pericardiocentesis yielded 500 mL of blood, and spontaneous circulation returned. Contrast-enhanced echocardiograms revealed inferolateral akinesis and a new, small myocardial slit with systolic extrusion of contrast medium, consistent with left ventricular free-wall rupture. During immediate open-heart surgery, a small hole in an area of necrotic tissue was discovered and repaired. This case highlights the usefulness of bedside contrast-enhanced echocardiography in confirming acute left ventricular free-wall rupture and enabling rapid surgical treatment.

Role of US Contrast Agents in the Assessment of Indeterminate Solid and Cystic Lesions in Native and Transplant Kidneys

Ultrasonography (US) is often the initial imaging modality employed in the evaluation of renal diseases. Despite improvements in B-mode and Doppler imaging, US still faces limitations in the assessment of focal renal masses and complex cysts as well as the microcirculation. The applications of contrast-enhanced US (CEUS) in the kidneys have dramatically increased to overcome these shortcomings with guidelines underlining their importance. This article describes microbubble contrast agents and their role in renal imaging. Microbubble contrast agents consist of a low solubility complex gas surrounded by a phospholipid shell. Microbubbles are extremely safe and well-tolerated pure intravascular agents that can be used in renal failure and obstruction, where computed tomographic (CT) and magnetic resonance (MR) imaging contrast agents may have deleterious effects. Their intravascular distribution allows for quantitative perfusion analysis of the microcirculation, diagnosis of vascular problems, and qualitative assessment of tumor vascularity and enhancement patterns. Low acoustic power real-time prolonged imaging can be performed without exposure to ionizing radiation and at lower cost than CT or MR imaging. CEUS can accurately distinguish pseudotumors from true tumors. CEUS has been shown to be more accurate than unenhanced US and rivals contrast material-enhanced CT in the diagnosis of malignancy in complex cystic renal lesions and can upstage the Bosniak category. CEUS can demonstrate specific enhancement patterns allowing the differentiation of benign and malignant solid tumors as well as focal inflammatory lesions. In conclusion, CEUS is useful in the characterization of indeterminate renal masses and cysts.

The use of echocardiography in acute cardiovascular care: Recommendations of the European Association of Cardiovascular Imaging and the Acute Cardiovascular Care Association

Echocardiography is one of the most powerful diagnostic and monitoring tools available to the modern emergency/critical care practitioner. Currently, there is a lack of specific European Association of Cardiovascular Imaging/Acute Cardiovascular Care Association recommendations for the use of echocardiography in acute cardiovascular care. In this document, we describe the practical applications of echocardiography in patients with acute cardiac conditions, in particular with acute chest pain, acute heart failure, suspected cardiac tamponade, complications of myocardial infarction, acute valvular heart disease including endocarditis, acute disease of the ascending aorta and post-intervention complications. Specific issues regarding echocardiography in other acute cardiovascular care scenarios are also described.

The use of echocardiography in acute cardiovascular care: recommendations of the European Association of Cardiovascular Imaging and the Acute Cardiovascular Care Association

Echocardiography is one of the most powerful diagnostic and monitoring tools available to the modern emergency/ critical care practitioner. Currently, there is a lack of specific European Association of Cardiovascular Imaging/Acute Cardiovascular Care Association recommendations for the use of echocardiography in acute cardiovascular care. In this document, we describe the practical applications of echocardiography in patients with acute cardiac conditions, in particular with acute chest pain, acute heart failure, suspected cardiac tamponade, complications of myocardial infarction, acute valvular heart disease including endocarditis, acute disease of the ascending aorta and post-intervention complications. Specific issues regarding echocardiography in other acute cardiovascular care scenarios are also described.

An observational study of the occurrence of serious adverse reactions among patients who receive optison in routine medical practice

BACKGROUND

Reports of ultrasound contrast agent safety have been derived mainly from retrospective databases rather than from studies specifically designed to assess safety. The purpose of this study was to prospectively determine the safety of Optison (GE Healthcare, Princeton, NJ) in routine medical practice.

METHODS

Patients referred for routine rest or stress two-dimensional echocardiography who had indications for contrast were enrolled. Vital signs were obtained at baseline and at intervals up to 1 hour after dosing of Optison. Patients were followed for the development of any serious adverse event (SAE), defined as an event that causes death, is life threatening, requires or prolongs hospitalization, or causes another important event, for 24 hours after Optison administration.

RESULTS

A total of 1,039 patients were enrolled, and 76% had 24-hour follow-up. The median age was 60 years (range, 20-97 years), and 62% were men. The mean body mass index was 33 ± 9 kg/m(2). Patient comorbidities included hypertension (73%), hyperlipidemia (64%), smoking (52%), and diabetes (37%). There were significant increases in systolic blood pressure, heart rate, and respiratory rate between the baseline, 5- to 15-min, 30-min, and 60-min time points after the administration of Optison in patients undergoing stress studies but none in those undergoing rest studies. There was a total of six SAEs during the study, which were felt to be related not to Optison but rather to the stress test itself or to the patient's underlying pathology. Although two events were classified as SAEs because of hospitalization, the hospitalizations were appropriate for pathology that would have been missed without Optison use.

CONCLUSIONS

In this large, prospective safety study of Optison during routine resting and stress echocardiography, no SAEs related to Optison developed. Optison helped define abnormalities that required appropriate hospitalization for further management.

Safety of ultrasound contrast agents in patients with known or suspected cardiac shunts

Contrast-enhanced ultrasound imaging is a radiation-free diagnostic tool that uses biocompatible ultrasound contrast agents (UCAs) to improve image clarity. UCAs, which do not contain dye, often salvage "technically difficult" ultrasound scans, increasing the accuracy and reliability of a front-line ultrasound diagnosis, reducing unnecessary downstream testing, lowering overall health care costs, changing therapy, and improving patient care. Two UCAs currently are approved and regulated by the US Food and Drug Administration. They have favorable safety profiles and risk/benefit ratios in adult and pediatric populations, including compromised patients with severe cardiovascular diseases. Nevertheless, these UCAs are contraindicated in patients with known or suspected right-to-left, bidirectional, or transient right-to-left cardiac shunts. These patients, who constitute 10% to 35% of the general population, typically receive no UCAs when they undergo echocardiography. If their echocardiographic images are suboptimal, they may receive inappropriate diagnosis and treatment, or they may be referred for additional diagnostic testing, including radiation-based procedures that increase their lifetime risk for cancer or procedures that use contrast agents containing dye, which may increase the risk for kidney damage. An exhaustive review of current peer-reviewed research demonstrated no scientific basis for the UCA contraindication in patients with known or suspected cardiac shunts. Initial safety concerns were based on limited rodent data and speculation related to macroaggregated albumin microspheres, a radioactive nuclear imaging agent with different physical and chemical properties and no relation to UCAs. Radioactive macroaggregated albumin is not contraindicated in adult or pediatric patients with cardiac shunts and is routinely used in these populations. In conclusion, the International Contrast Ultrasound Society Board recommends removal of the contraindication to further the public interest in safe, reliable, radiation-free diagnostic imaging options for patients with known or suspected cardiac shunts and to reduce their need for unnecessary downstream testing.

Contrast-enhanced ultrasound to evaluate changes in renal cortical perfusion around cardiac surgery: a pilot study

Introduction

Contrast-enhanced ultrasound (CEUS) is a new technique that might enable portable and non-invasive organ perfusion quantification at the bedside. However, it has not yet been tested in critically ill patients. We sought to establish CEUS's feasibility, safety, reproducibility and potential diagnostic value in the assessment of renal cortical perfusion in the peri-operative period in cardiac surgery patients.

Methods

We recruited twelve patients deemed at risk of acute kidney injury (AKI) planned for elective cardiac surgery. We performed renal CEUS with destruction-replenishment sequences before the operation, on ICU arrival and the day following the admission. Enhancement was obtained with Sonovue^® (Bracco, Milano, Italy) at an infusion rate of 1 ml/min. We collected hemodynamic parameters before, during and after contrast agent infusion. At each study time, we obtained five video sequences, which were analysed using dedicated software by two independent radiologists blinded to patient and time. The main output was a perfusion index (PI), corresponding to the ratio of relative blood volume (RBV) over mean transit time (mTT).

Results

All 36 renal CEUS studies, including 24 in the immediate post-operative period could be performed and were well tolerated. Correlation between readers for PI was excellent (R² = 0.96, P < 0.0001). Compared with baseline, there was no overall difference in median PI's on ICU admission. However, the day after surgery, median PI's had decreased by 50% (P < 0.01) (22% decrease in RBV (P = 0.09); 48% increase in mTT (P = 0.04), both suggestive of decreased perfusion). These differences persisted after correction for haemoglobin; vasopressors use and mean arterial pressure. Four patients developed AKI in the post-operative period.

Conclusions

CEUS appears feasible and well-tolerated in patients undergoing cardiac surgery even immediately after ICU admission. CEUS derived-parameters suggest a decrease in renal perfusion occurring within 24 hours of surgery.

Clinical application and laboratory protocols for performing contrast echocardiography

Technically difficult echocardiographic studies with suboptimal images remain a significant challenge in clinical practice despite advances in imaging technologies over the past decades. Use of microbubble ultrasound contrast for left ventricular opacification and enhancement of endocardial border detection during rest or stress echocardiography has become an essential component of the operation of the modern echocardiography laboratory. Contrast echocardiography has been demonstrated to improve diagnostic accuracy and confidence across a range of indications including quantitative assessment of left ventricular systolic function, wall motion analysis, and left ventricular structural abnormalities. Enhancement of Doppler signals and myocardial contrast echocardiography for perfusion remain off-label uses. Implementation of a contrast protocol is feasible for most laboratories and both physicians and sonographers will require training in contrast specific imaging techniques for optimal use. Previous concerns regarding the safety of contrast agents have since been addressed by more recent data supporting its excellent safety profile and overall cost-effectiveness.

Use of contrast echocardiography in intensive care and at the emergency room

Bedside echocardiography in emergency room (ER) or in intensive care unit (ICU) is an important tool for managing critically ill patients, to obtain a timely accurate diagnosis and to immediately stratify the risk to the patient’s life. It may also render invasive monitoring unnecessary. In these patients, contrast echocardiography may improve quality of imaging and also may provide additional information, especially regarding myocardial perfusion in those with suspected coronary artery disease. This article focuses on the principle of contrast echocardiography and the clinical information that can be obtained according to the most frequent presentations in ER and ICU.

Advanced echocardiographic techniques

Echocardiography has advanced significantly since its first clinical use. The move towards more accurate imaging and quantification has driven this advancement. In this review, we will briefly focus on three distinct but important recent advances, three‐dimensional (3D) echocardiography, contrast echocardiography and myocardial tissue imaging. The basic principles of these techniques will be discussed as well as current and future clinical applications.

Implementation of echocardiographic contrast agents into clinical practice: a United Kingdom National Health Service Survey on behalf of the British Society of Echocardiography

AIMS

The administration of echocardiographic contrast agents has been shown to improve accuracy and be cost-effective in patients with suboptimal endocardial definition. We sought to investigate the implementation of contrast agents in clinical practice.

METHODS AND RESULTS

An electronic questionnaire was devised to determine the use of contrast ultrasound agents in clinical practice and sent electronically to echocardiography departments at each national health service hospital within the UK. Out of 198, 107 departments responded (54%). Out of 673,121 echocardiograms, 25,834 (3.8%) were performed with contrast. Out of 551 echocardiography machines, 358 (65%) were suitable for contrast use. Of the sonographers, out of 711, 112 (15.8%) could perform i.v. cannulation and 42 (5.9%) could administer contrast independently. The median time for an echocardiographic examination was 30 min (inter-quartile range 30-45 min). Significant predictors of contrast use were the presence of a consultant cardiologist with subspecialty training in echocardiography (odds ratio 8.7, P = 0.004), the presence of a stress echocardiography service (odds ratio 2.3, P = 0.004), and the presence of a physician during the day (odds ratio 3.0, P = 0.04). Reasons for impediment in administering contrast were staff training (34.6%), extra time required for a contrast study (29.9%), and the expense of contrast (18.7%).

CONCLUSION

The use of echocardiographic contrast agents within routine echocardiographic practice in the UK is limited to <4% of all transthoracic echocardiographic studies. Major barriers to the implementation of contrast use are the absence of cardiac imaging specialists directly supervising echocardiography departments and the training of sonographers to independently administer contrast.

Evaluation of ultrasound-assisted thrombolysis using custom liposomes in a model of retinal vein occlusion

PURPOSE

To study the potential efficacy of ultrasound (US) assisted by custom liposome (CLP) destruction as an innovative thrombolytic tool for the treatment of retinal vein occlusion (RVO).

METHODS

Experimental RVO was induced in the right eyes of 40 rabbits using laser photothrombosis; the US experiment took place 48 hours later. Rabbits were randomly divided into four equal groups: US+CLP group, US+saline group, CLP+sham US group, and no treatment group. The latter three groups acted as controls. Fundus fluorescein angiography and Doppler US were used to evaluate retinal blood flow.

RESULTS

CLP-assisted US thrombolysis resulted in restoration of flow in seven rabbits (70%). None of the control groups showed significant restoration of retinal venous blood flow.

CONCLUSIONS

US-assisted thrombolysis using liposomes resulted in a statistically significant reperfusion of retinal vessels in the rabbit experimental model of RVO. This approach might be promising in the treatment of RVO in humans. Further studies are needed to evaluate this approach in patients with RVO. Ultrasound assisted thrombolysis can be an innovative tool in management of retinal vein occlusion.

Administration of perflutren contrast agents during transthoracic echocardiography is not associated with a significant increase in acute mortality risk

BACKGROUND

Despite the 2008 revision of a previously issued black box warning of the US Food and Drug Administration against the use of perflutren ultrasound contrast agents, the warning still reports fatalities having occurred following their administration. We sought to assess 1-day mortality associated with contrast use across a wide range of clinical settings and co-morbidities.

METHODS

We conducted a retrospective study involving 96,705 transthoracic echocardiograms (TTE) in 63,189 adults at our institution between July 2003 and June 2008. A contrast agent was used in 2,518 TTE during this time. The primary outcome was total mortality within 1 day of TTE.

RESULTS

Death occurred in 10 patients (0.44%) in the contrast group and in 421 patients (0.69%) in the non-contrast group (p = 0.14). In a multivariate model, use of contrast enhancement was not associated with increased mortality (p = 0.67) after adjustment for age, gender, race, patient location, ejection fraction, and the presence of various co-morbidities. Cause of death analysis did not identify any cases where contrast played a likely role.

CONCLUSION

Definity contrast use during TTE was not associated with increased acute mortality risk. Contrast administration during TTE should not be withheld when the additional information obtained could potentially improve patient management.