Ultrasound contrast agents (UCAs) are currently used throughout the world in both clinical and research settings. The concept of contrast-enhanced ultrasound imaging originated in the late 1960s, and the first commercially available agents were initially developed in the 1980s. Today's microbubbles are designed for greater utility and are used for both approved and off-label indications. In October 2007, the US Food and Drug Administration (FDA) imposed additional product label warnings that included serious cardiopulmonary reactions, several new disease-state contraindications, and a mandated 30 min post-procedure monitoring period for the agents Optison and Definity. These additional warnings were prompted by reports of cardiopulmonary reactions that were temporally related but were not clearly attributable to these UCAs. Subsequent published reports over the following months established not only the safety but also the improved efficacy of clinical ultrasound applications with UCAs. The FDA consequently updated the product labeling in June 2008 and reduced contraindications, although it continued to monitor select patients. In addition, a post-marketing program was proposed to the sponsors for a series of safety studies to further assess the risk of UCAs. Then in October 2011, the FDA leadership further downgraded the warnings after hearing the results of the post-marketing data, which revealed continued safety and improved efficacy. The present review focuses on the use of UCAs in today's clinical practice, including the approved indications, a variety of off-label uses, and the most recent data, which affirms the safety and efficacy of UCAs.
Andrew W Appis, Melissa J Tracy, and Steven B Feinstein
Stella Kyung, Alan Goldberg, Steven Feinstein, Stephanie Wilson, Sharon Mulvagh, and Petros Nihoyannopoulos
The 34th annual Advances in Contrast Ultrasound (ACU) International Bubble Conference convened in Chicago, IL, USA, on September 5–6, 2019 to feature new directions of research, preclinical and first-in-man clinical trials, and novel clinical applications highlighting the diversity and utility of contrast enhanced ultrasound (CEUS). An expert group comprising clinicians, engineers, basic scientists, government officials, attorneys, and industry partners convened to collaborate on cutting-edge ultrasound enhancement technology. Utilizing this information, the International Contrast Ultrasound Society (ICUS) continues to have cause to advocate for the safe and appropriate use of CEUS with expanding indications and applications.
Hena Patel, Stephen Boateng, Gurpreet Singh, and Steven Feinstein
Spontaneous echo contrast (SEC) is frequently observed in patients with structural and functional cardiovascular abnormalities. Literature describes cases of SEC either from agglutination of red blood cells and plasma proteins or from microcavitations. SEC secondary to the former is an independent predictor of future thromboembolic events and is most commonly observed in the left atrium or left atrial appendage. Thus, many authors reason that left atrial SEC is an indication for initiating anticoagulant therapy. We report a rare case of right atrial SEC that was incidentally found during echocardiographic evaluation of isolated peripheral edema in a healthy adult with a structurally normal heart. At present, there are no studies to offer guidance for management of right atrial SEC. This case emphasizes a necessary area of future research.
- Cardiovascular implications of SEC.
- Diagnostic evaluation and management of SEC.