Yield of Echocardiography with Bubble Studies Among Acute Ischemic Stroke Patients

<b>Background:</b> Transthoracic (TTE) and transesophageal (TEE) echocardiographic studies with agitated saline, also known as "bubble studies" (BSs), are used to diagnose patent foramen ovales (PFOs) in cryptogenic strokes (CSs). Guidelines limit PFO closure recommendations to CS patients ≤ 60 but BSs are often performed as part of standard order sets, leading to inappropriate studies in older patients with already-established stroke etiologies. <b>Methods:</b> This retrospective single-center study included acute ischemic stroke patients between January 2021 and June 2022 and assessed the stroke etiology and number of the echocardiographic studies performed. <b>Results:</b> A total of 663 patients were admitted during this period with 413 (62.3%) classified as non-CS. Overall, 390 (58.8%) TTE and 40 (6.0%) TEE with BSs were conducted. Of that, non-CS patients received 252 TTE and 17 TEE with BSs. PFOs were diagnosed in 36 CS and 18 non-CS patients and 14 of the 15 PFO closures were performed in the CS patients for primary stroke prevention. The one closure in the non-CS patient was performed in conjunction with the open excision of a mitral valve mass. <b>Conclusions:</b> Therefore, the majority of the BSs performed in non-CS patients yielded no change in management. Our study identifies a large volume of diagnostic studies that are not supported by current clinical guidelines and instead, may contribute to healthcare waste. A new institutional protocol should be established to improve operational efficiency and reduce the downstream implications of diagnostic overuse in ischemic stroke care.