Additive Value of Transesophageal Echocardiography Without Sedation for Diagnosis of a High-Risk Patent Foramen Ovale

BACKGROUND AND OBJECTIVES: Recent studies have highlighted the validity of risk stratification based on using the concept of 'a high-risk patent foramen ovale (HRPFO)'. We sought to compare transesophageal contrast echocardiography (cTEE) without sedation and transthoracic contrast echocardiography (cTTE) for the diagnosis of HRPFO. METHODS: Clinical data from patients who underwent both cTTE and cTEE without sedation for the evaluation of cryptogenic stroke were retrospectively analyzed. HRPFO was defined as a patent foramen ovale (PFO) associated with an atrial septal aneurysm (ASA) or a hypermobile atrial septum, and a PFO with significant shunting (≥20 bubbles), or a PFO size (measured as the distance between the septum secundum and primum) of ≥2 mm. RESULTS: In 572 patients who underwent both cTTE and cTEE without sedation, the prevalence of PFO was 65.9% (377 patients), and 331 patients (57.9% of the total, 87.8% of those with PFOs) were diagnosed with HRPFO. A significantly higher prevalence of PFO (65.9% vs. 57.7%, p<0.001) and ASA or hypermobile atrial septum (27.8% vs. 17.5%, p<0.001) was observed with cTEE compared to cTTE, as well as a significantly higher prevalence of significant shunting (49.8% vs. 45.2%, p=0.003). Consequently, the prevalence of HRPFO increased from 46.0% (263/572) to 56.8% (325/572) with the addition of cTEE (p<0.001). CONCLUSIONS: The diagnosis of PFO and HRPFO was more effectively achieved using cTEE without sedation. Considering the advantageous outcomes associated with the percutaneous closure of HRPFO, both cTTE and cTEE without sedation may be considered viable screening methods for patients with cryptogenic stroke.