Title <p>Innovative Use of Carbonated Beverage for Diagnosis of Sliding Hiatus Hernia on Transthoracic Echocardiography: A Case Report.</p> Background <p>Transthoracic echocardiography (TTE) is a valuable diagnostic tool for evaluating cardiac pathology; however, gastrointestinal structures such as hiatus hernias can occasionally mimic cardiac conditions on TTE. This case highlights the potential for misinterpretation when a well-defined, echo-lucent or echogenic mass is located posterior to the left atrium, as these can be mistakenly attributed to cardiac pathology.</p> Case Presentation <p>We report a 25-year-old female patient presenting with atypical chest symptoms, including palpitations, where initial TTE revealed an extracardiac mass posterior to the left atrium. To further investigate the structure, the patient ingested 200&#xa0;mL of Lucozade, a carbonated beverage. Repeat TTE promptly thereafter demonstrated swirling echogenic contrast within the mass, which moved synchronously with the patient’s respiration and peristalsis, confirming the diagnosis of a sliding hiatus hernia.</p> Discussion <p>This simple bedside intervention enabled real-time clarification of the finding, obviating the need for additional imaging. The patient was reassured, referred for outpatient gastroenterology assessment, and scheduled for ambulatory ECG monitoring. The case underscores the importance of considering gastrointestinal structures in the differential diagnosis of masses seen on TTE, particularly due to their proximity to the heart. In this case, the ingestion of a carbonated beverage provided dynamic, low-cost contrast enhancement, enabling rapid and accurate diagnosis.</p> Conclusion <p>The use of a carbonated beverage during TTE can serve as an innovative, cost-effective diagnostic aid when ambiguous extracardiac structures are encountered. This approach may help avoid unnecessary investigations and illustrates the value of creative techniques in everyday clinical practice.</p>