Echocardiographic identification of combined hereditary hemorrhagic telangiectasia and juvenile polyposis syndrome: The critical role of sonographer awareness and accuracy for optimal patient outcomes

Background: The following case outlines the value of transthoracic echocardiography (TTE) and agitated saline studies in the investigation of complications associated with the rare disorder hereditary hemorrhagic telangiectasia (HHT), and combined HHT–juvenile polyposis syndrome (JPS). Complications arising from such conditions include pulmonary arteriovenous malformations (PAVMs), high-output cardiac failure, thoracic aortic dilatation (in HHT-JPS), and left atrial enlargement. Echocardiography is a highly sensitive initial screening test for extracardiac shunting; its detection allows for intervention and further imaging to be initiated in patients. Methods: A 45-year-old female presented with a known SMAD4 gene mutation and history of epistaxis. A complete TTE study was performed, including an agitated saline contrast study. A three-way stopcock was used to agitate the saline by flushing the 8mL of saline and 1mL of blood combined with 1 mL of air from one syringe to the other syringe. Saline was rapidly injected into the vein in the supine and sitting positions. Results: Agitated saline contrast echocardiography demonstrated 1+ bubbles entering the left atrium after four cardiac cycles following opacification of the right atrium, suggestive of intrapulmonary shunting. This resulted in a possible diagnosis of HHT-JPS. Conclusions: The high-level sonographer skill required to accurately quantify extracardiac shunt severity in agitated saline studies and the possible benefits of novel tools such as pre-agitated saline is discussed in this report. Methods to obtain accurate measurements for the most accurate cardiac output calculation are explored. The importance of sonographer awareness of such rare diseases and their manifestations is crucial to accurately provide clinical information when investigating all possible complications.