An Observational Study On Supine-Tostanding TCD Test And VM Test In Patients With Orthostatic Intolerance

Objective: To explore the application of supine-to-standing TCD test and VM test on segregating OI patients with different clinical type and explore different characteristics of cerebral hemodynamic changes in OI patientMethods: From September 2018 to February 2019,patients with orthostatic intolerance were recruited from Department of Neurology,1st Affiliated Hospital of University of South.Clinical information of patients were obtained and orthostatic intolerance questionnaire were completed.Transcrianal Doplar(TCD)were performed in all patients to measure baseline cerebral blood flow velocity in supine position,observe the W spike,and calculate the cerebral blood flow velocity score during orthostatic positin.The blood pressure and heart rate were measured in supine positing and at 1,3 and 5 minutes of orthostatic position.The changes of cerebral blood flow velocity during valsalva maneuver were recorded,and the Cerebral blood flow index were calculated.Results: A total of 124 patients were enrolled for this study.25(20.2%)were females and 99(79.8%)were males.The active standing test wereperformed in all patients.The patients were divided into groups according to the results of supine-to-standing test.The number of unclassified OI patients was reduced from 93 to 41 after application of supine-to-standing TCD test(?2=58.808,P<0.000).22 were healthy controls,44 were normal responders,16 were OCHOs,14 were OH-C,22 were OH-U,22 were OHTN,3 were POTS,and 3 were PST.The score of orthostatic intolerance in OH-U group was the highest,which was significantly different from normal response group(P < 0.01).There was no significant difference in baseline heart rate and basline mCBFV in VM(P=0.15)between groups from each other.There was no significant difference in the lowest mCBFv of phase II(P=0.15)between groups from each other.There were significant differences in mCBFv of phase II-L between healthy control group and normal response group(P < 0.001).There were significant differences in mCBFv of phase II-L between healthy control group and OH-U group(P<0.01).There were significant difference in in mCBFv of phase II-L between healthy control group and OH-C group(P<0.05).There were significant difference in mCBFv at the Phase IV between healthy control group and OH-U group(P < 0.05);or between healthy control group and normal response group(P < 0.05),no significant difference between OI groups.The difference in VR between healthy control group and normal response group were significant difference(P < 0.001),The difference in VR between healthy control groupand OH-C group were significant difference(P < 0.05),There were significant difference in VR between healthy control group and OH-U group(P < 0.05).Cerebral blood flow index?were unable to segregate healthy control group from OI group.Cerebral blood flow index?were able to segregate healthy control group from normal response group(P < 0.05),and segregate OI groups from each other.Cerebral blood flow index ? were able to healthy control group from normal response group(P < 0.05),and healthy control group from other OI groups.Cerebral blood flow index ?were only able to segregate healthy control group from OH-U and OHCgroup(P < 0.05).W spike was incomplete in OH-U group(72.7%).The phase II-L mCBFv was correlated with incomplete of W spike(?=0.39,P<0.05)Conclusion 1.The supine-to-standing TCD test have diagnosis and antidiastole value on OI syndrome.2.Cerebral blood flow index?were able to segregate healthy control group from OI patient(P < 0.05),and segregate OI groups from each other.3.The incompletion of W wave is related to the severity of autonomic dysfunction in OI patient.