Diagnostic Value of Micro-Bubble Transcranial Doppler Combined with Contrast Transthoracic Echocardiography in Cryptogenic Stroke Patients with Patent Foramen Ovale

In recent years, increasing attention has been paid to cryptogenic stroke (CS) caused by the patent foramen ovale (PFO).This study aims to evaluate the value of microbubble transcranial Doppler (MB-TCD) combined with contrast transthoracic echocardiography (cTTE) in the diagnosis of cryptogenic stroke patients with PFO.From January 2014 to January 2019, patients who suffered from CS were recruited and divided into the cTTE group and MB-TCD combined with cTTE group. All patients were further checked by transesophageal echocardiography (TEE).A total of 130 patients accepted cTTE examination, and 109 patients accepted MB-TCD combined with cTTE. In the group, 52 of the 54 positive patients were finally confirmed by TEE with PFO, and 12 of the 76 negative patients were finally confirmed by TEE with PFO. In combined group, 50 patients were negative on both two examination (Negative group), 54 were positive on both two examination (Positive group) and finally confirmed by TEE indeed with patent foramen ovale (PFO), while remaining five (5) patients were positive only on MB-TCD (Suspected group). After checked by TEE, three (3) of five patients with MB-TCD positive were confirmed by TEE indeed with PFO. The sensitivity, specificity, positive likelihood ratio (+LR), and Youden's index of cTEE in diagnostic of cryptogenic stroke patients with PFO were 81.25%, 96.97%, 26.82 and 0.78, respectively, and these for MB-TCD combined with cTTE were 100%, 96.15%, 25.97 and 0.96, respectively. MB-TCD medium can sensitively discover PFO in cryptogenic stroke patients with 100% sensitivity and a missdiagnosis rate of 0.The combination of MB-TCD and cTTE can improve the sensitivity and specificity of PFO diagnosis in cryptogenic stroke patients. MB-TCD medium also had high sensitivity and specificity.