Agitated saline contrast echocardiography reveals a systemic‐to‐pulmonary venous shunt

Abstract

Contrast echocardiography with agitated saline is used to assess mainly the existence of interatrial communication. We report a case of a 26-year-old woman, with a "port-a-cath" central venous line, who had an unusual finding in agitated saline contrast echocardiography. Multimodality imaging revealed occlusion of superior vena cava and a systemic-to-pulmonary venous shunt.

Myocardial Enhancement Following Agitated Saline Contrast Study in a Boxer Dog

“…Agitated saline contrast echocardiographic studies are frequently used to aid in the detection of abnormal intracardiac communications such as atrial and ventricular septal defects, patent foramen ovale, or intrapulmonary (arteriovenous) shunts. 1 , 2 , 3 , 4 , 6 , 7 , 8 The intravenous administration of agitated saline poses a theoretical risk of air embolization when right-to-left shunts are present, potentially predisposing to tissue ischemia or infarction. There is particular concern for the possibility of myocardial infarction from coronary air embolization.…”

“… 5 , 9 In people, paradoxical cerebral air embolisms have been reported following agitated saline study, resulting in transient ischemic attacks or cerebrovascular accidents. 1 , 6 , 10 Associated clinical signs have included transient dizziness, weakness, left-sided paresthesia, and migraines. 10 In rat models, bubbles >45 μm in diameter caused ischemic infarctions in the regions supplied by the right carotid artery.…”

“…While size and location of the bubbles appear to be the most important risk factors for infarction, ideal bubble size is difficult to predict and standardize because of dynamic bubble behaviors that can include coalescence, dissolution, and splitting. 2 , 6 An in vitro closed-circuit study showed the potential dangers of bubbles >45 μm. 2 Generally, lower volumes of air resulted in fewer bubbles >45 μm, but bubbles up to 100 μm could still be created, and injected volumes as low as 0.025 mL resulted in myocardial vessel occlusion in vitro.…”

“…Saline contrast echocardiography is therefore considered confirmatory for a right-to-left shunt when microbubbles are detected in the left side of the heart following intravenous injection. 1 , 2 , 3 , 4 , 5 , 6 …”