Abstract 3266: Detection Of Patent Foramen Ovale By Transesophageal Echocardiography and Contrast-Enhanced Cardiac Magnetic Resonance In Patients With Cryptogenic Stroke.
Background. In ≈ 40% of patients with acute ischemic stroke, the cause remains undefined (cryptogenic stroke). Previous studies, using contrast echocardiography, showed a significant prevalence of a patent foramen ovale (PFO) in patients with cryptogenic stroke < 55 years of age, suggesting a causal role through paradoxical embolism. Contrast transesophageal echocardiography (TEE) is considered the gold standard for PFO detection. Recently, however, cardiac magnetic resonance (CMR) was also shown to reliably detect PFO. In this study we compared the accuracy of CMR and TEE in detecting PFO in a group of patients with cryptogenic stroke.
Methods and Results. Sixteen patients (age 50 ± 13 years, 9 males) with cryptogenic ischemic stroke underwent contrast-enhanced TEE and contrast CMR for detection of possible PFO. Both imaging studies were performed during Valsalva maneuver. PFO grading results were assessed visually both for TEE and CMR, according to the entity of contrast passage in the left atrium (grade 0 = no PFO; grades 1, 2 and 3 = mild, medium and wide PFO, respectively). Nine patients (56%) were identified to have a PFO by contrast TEE. Contrast-enhanced CMR identified a PFO in only 5 (56%) of these patients. None of the 7 patients without PFO at TEE was shown to have a PFO at CMR. TEE showed a grade 1 PFO in 4 patients, a grade 2 PFO in 3 and a grade 3 PFO in 2 patients. Of these patients, CMR failed to identify PFO in all patients with a grade 1 PFO at TEE and underestimated the degree of the shunt in the other patients.
Conclusions. Our data suggest that TEE should be considered the non-invasive diagnostic reference test to detect and characterize PFO in patients with ischemic cryptogenic stroke.