Evaluation Of Patent Foramen Ovale And Effects Of Closure In Patients With Cryptogenic Cerebrovascular Events With Transthoracic Contrast Echocardiography

PART ? Evaluation of Patent Foramen Ovale in Patients with Cryptogenic Cerebrovascular Events with Transthoracic Contrast EchocardiographyObjective:To evaluate the diagnostic value of transthoracic contrast echocardiography in patent foramen ovale (PFO), and to analysis clinical characteristics of patients with cryptogenic cerebrovascular events.Methods:A total of 188 patients with cryptogenic cerebrovascular events including 110 cases with stroke,30 cases with transient ischemic attack,35 cases with migraine and 13 cases with other paradoxical embolism were obtained in our study. All of the patients were underwent transthoracic contrast echocardiography and were divided into four grades according to degrees of right to left shunting. The results were compared with those in 75 healthy volunteers.117 patients received transesophageal echocardiography (TEE). The difference between transthoracic contrast echocardiography and TEE results was compared. Risk of paradoxical embolism scores were calculated in each patient with PFO detected by transthoracic contrast echocardiography.Results:183 patients and 75 healthy volunteers were successful for transthoracic contrast echocardiography both at rest and during Valsalva maneuver. When transthoracic contrast echocardiography was used to detect PFO, frequency of PFO in patients with cryptogenic cerebrovascular events was significantly higher than that in controls. Furthermore, the frequency of cases of right to left shunting grade ? at rest and right to left shunting grade ? during Valsalva maneuver were significantly higher than those in the control group when transthoracic contrast echocardiography was performed. Compared with transthoracic contrast echocardiography, the positive rate of PFO was lower when TEE was undertaken. Furthermore, the positive rate of PFO detection by TEE was higher in patients with right to left shunting grade ? and grade ? compared with that in patients with right to left shunting grade ?.The risk of paradoxical embolism scores in patients in each group divided by right to left shunting degrees were not significantly different.Conclusions:Transthoracic contrast echocardiography can be conventionally used to screen the prevalence of PFO. The positive rate of detecting PFO with transthoracic contrast echocardiography is higher than TEE. In addition, compared with patients with right to left shunting grade ?, the positive rate of PFO detection by TEE is higher in patients with right to left shunting grade ? and grade ?. PFO is associated with cryptogenic cerebrovascular events. The presence of PFO in patients with cryptogenic cerebrovascular events is significantly higher than that in controls both at rest and during Valsalva maneuver.PART II Follow-up Study for Effects of Patent Foramen Ovale Closure on Prevention of Recurrent Cryptogenic Cerebrovascular EventsObjective:To compare the effects of patent foramen ovale (PFO) closure and medical therapy on prevention of recurrent cryptogenic cerebrovascular events and analysis the relationship between transthoracic contrast echocardiography and clinical characteristicses and recurrent cryptogenic cerebrovascular events in two therapeutic methods.Methods:A total of 66 patients with cryptogenic cerebrovascular events including 53 cases with stroke,4 cases with transient ischemic attack,4 cases with migraine and 5 cases with other paradoxical embolism were obtained in our study. All these patients were associated with PFO.32 patients received PFO closure and the other 34 patients received antiplatelet therapy. A follow-up study by telephone was performed to record situations of symptoms improvement, recurrent cryptogenic cerebrovascular events, readmission, other embolism events, atrial fibrillation, bleeding, blood pressure and smoke. Risk of paradoxical embolism scores were calculated in all of these patients. Logistic regression was used to analysis the relationship between transthoracic contrast echocardiography and clinical characteristicses and recurrent cryptogenic cerebrovascular events in two therapeutic methods.Results:In a mean follow up of 13.5 ±7.3 months, there was no serious event such as death and readmission and other complications associated with PFO closure and antiplatelet therapy in both two groups. The difference between PFO closure group and antiplatelet therapy group was not statistically significant on effects of preventing cryptogenic cerebrovascular events recurrence. In addition, the posttreatment recurrence rate in patients with a shunting at rest was statistically higher.Conclusions:PFO closure is not beneficial as compared to antiplatelet therapy in prevention of recurrent cryptogenic cerebrovascular events. A shunting at rest is an independent risk factor to predict recurrent cryptogenic cerebrovascular events after treatments. Because of minor specimen, further research is needed to confirm conslusions above.