{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T01:51:08Z","timestamp":1790214668024,"version":"4.1.0"},"reference-count":77,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"3","content-domain":{"domain":["www.ahajournals.org"],"crossmark-restriction":true},"short-container-title":["JAHA"],"published-print":{"date-parts":[[2025,2,4]]},"abstract":"<jats:p xml:lang=\"en\">Cerebral blood flow (CBF) is vital for delivering oxygen and nutrients to the brain. Many forms of orthostatic intolerance (OI) involve impaired regulation of CBF in the upright posture, which results in disabling symptoms that decrease quality of life. Because CBF is not easy to measure, rises in heart rate or drops in blood pressure are used as proxies for abnormal CBF. These result in diagnoses such as postural orthostatic tachycardia syndrome and orthostatic hypotension. However, in many other OI syndromes such as myalgic encephalomyelitis\/chronic fatigue syndrome and long COVID, heart rate and blood pressure are frequently normal despite significant drops in CBF. This often leads to the incorrect conclusion that there is nothing hemodynamically abnormal in these patients and thus no explanation or treatment is needed. There is a need to measure CBF, as orthostatic hypoperfusion is the shared pathophysiology for all forms of OI. In this review, we examine the literature studying CBF dysfunction in various syndromes with OI and evaluate methods of measuring CBF including transcranial Doppler ultrasound, extracranial cerebral blood flow ultrasound, near infrared spectroscopy, and wearable devices.<\/jats:p>","DOI":"10.1161\/jaha.124.036752","type":"journal-article","created":{"date-parts":[[2025,2,3]],"date-time":"2025-02-03T10:17:31Z","timestamp":1738577851000},"update-policy":"https:\/\/doi.org\/10.1161\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":18,"title":["Cerebral Blood Flow in Orthostatic Intolerance"],"prefix":"10.1161","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1250-6351","authenticated-orcid":false,"given":"Muhammad Shahzeb","family":"Khan","sequence":"first","affiliation":[{"name":"Department of Medicine Duke University Medical Center Durham Durham NC USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6462-1039","authenticated-orcid":false,"given":"Amanda J.","family":"Miller","sequence":"additional","affiliation":[{"name":"Department of Physical Therapy Lebanon Valley College Annville PA USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0195-0000","authenticated-orcid":false,"given":"Arooba","family":"Ejaz","sequence":"additional","affiliation":[{"name":"Department of Medicine Dow University of Health Sciences Karachi Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0608-3305","authenticated-orcid":false,"given":"Jeroen","family":"Molinger","sequence":"additional","affiliation":[{"name":"Department of Medicine Duke University Medical Center Durham Durham NC USA"},{"name":"Department of Anesthesia Duke University Medical Center Durham NC USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7474-3737","authenticated-orcid":false,"given":"Parag","family":"Goyal","sequence":"additional","affiliation":[{"name":"Department of Medicine Weill Cornell Medicine New York NY USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5989-3961","authenticated-orcid":false,"given":"David B.","family":"MacLeod","sequence":"additional","affiliation":[{"name":"Department of Anesthesia Duke University Medical Center Durham NC USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ashley","family":"Swavely","sequence":"additional","affiliation":[{"name":"Department of Medicine Duke University Medical Center Durham Durham NC USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elyse","family":"Wilson","sequence":"additional","affiliation":[{"name":"Department of Medicine Duke University Medical Center Durham Durham NC USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Meghan","family":"Pergola","sequence":"additional","affiliation":[{"name":"Department of Medicine Duke University Medical Center Durham Durham NC USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Harikrishna","family":"Tandri","sequence":"additional","affiliation":[{"name":"Department of Medicine Vanderbilt University Medical Center Nashville TN USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Camille Frazier","family":"Mills","sequence":"additional","affiliation":[{"name":"Department of Medicine Duke University Medical Center Durham Durham NC USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5890-3785","authenticated-orcid":false,"given":"Satish R","family":"Raj","sequence":"additional","affiliation":[{"name":"Department of Cardiac Sciences Libin Cardiovascular Institute, University of Calgary Calgary AB Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8671-7007","authenticated-orcid":false,"given":"Marat","family":"Fudim","sequence":"additional","affiliation":[{"name":"Department of Medicine Duke University Medical Center Durham Durham NC USA"},{"name":"Duke Clinical Research Institute Durham NC USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","reference":[{"key":"e_1_3_1_2_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.hrthm.2015.03.029"},{"key":"e_1_3_1_3_2","doi-asserted-by":"publisher","DOI":"10.1016\/B978-0-323-85492-4.00027-2"},{"key":"e_1_3_1_4_2","doi-asserted-by":"publisher","DOI":"10.1155\/2016\/6127340"},{"key":"e_1_3_1_5_2","doi-asserted-by":"publisher","DOI":"10.1111\/joim.12895"},{"key":"e_1_3_1_6_2","doi-asserted-by":"publisher","DOI":"10.1136\/bmjopen-2013-004127"},{"key":"e_1_3_1_7_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jaccas.2021.01.009"},{"key":"e_1_3_1_8_2","doi-asserted-by":"publisher","DOI":"10.1038\/s41579-022-00846-2"},{"key":"e_1_3_1_9_2","doi-asserted-by":"publisher","DOI":"10.1136\/bmj.m3026"},{"key":"e_1_3_1_10_2","doi-asserted-by":"publisher","DOI":"10.1002\/ana.26286"},{"key":"e_1_3_1_11_2","unstructured":"Long COVID Household Pulse Survey . Accessed August 6 2024. https:\/\/www.cdc.gov\/nchs\/covid19\/pulse\/long\u2010covid.htm."},{"key":"e_1_3_1_12_2","doi-asserted-by":"publisher","DOI":"10.3389\/fneur.2022.1012668"},{"key":"e_1_3_1_13_2","doi-asserted-by":"publisher","DOI":"10.3390\/jcdd8110156"},{"key":"e_1_3_1_14_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0002-9629(15)40480-X"},{"key":"e_1_3_1_15_2","doi-asserted-by":"publisher","DOI":"10.1038\/s41586-021-03553-9"},{"key":"e_1_3_1_16_2","doi-asserted-by":"publisher","DOI":"10.3390\/healthcare10102105"},{"key":"e_1_3_1_17_2","doi-asserted-by":"publisher","DOI":"10.1089\/ars.2010.3474"},{"key":"e_1_3_1_18_2","doi-asserted-by":"publisher","DOI":"10.1016\/B978-0-323-85492-4.00097-1"},{"key":"e_1_3_1_19_2","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.111164398"},{"key":"e_1_3_1_20_2","volume-title":"StatPearls","author":"Silverman A","year":"2024","unstructured":"Silverman A, Petersen NH. Physiology, Cerebral Autoregulation. StatPearls. Treasure Island (FL): Ineligible Companies. Disclosure: Nils Petersen declares no relevant financial relationships with ineligible companies; 2024."},{"key":"e_1_3_1_21_2","doi-asserted-by":"publisher","DOI":"10.1146\/annurev-med-041818-011630"},{"key":"e_1_3_1_22_2","doi-asserted-by":"publisher","DOI":"10.1152\/ajpheart.00738.2003"},{"key":"e_1_3_1_23_2","doi-asserted-by":"publisher","DOI":"10.1161\/JAHA.116.004417"},{"key":"e_1_3_1_24_2","doi-asserted-by":"publisher","DOI":"10.1097\/MAJ.0b013e318063c6c0"},{"key":"e_1_3_1_25_2","volume-title":"Cerebral Perfusion Pressure. In: StatPearls. Treasure Island (FL) Ineligible Companies","author":"Mount CA","year":"2024","unstructured":"Mount CA, Das JM. Cerebral Perfusion Pressure. In: StatPearls. Treasure Island (FL) Ineligible Companies. Joe Das declares no relevant financial relationships with ineligible companies: Disclosure; 2024."},{"key":"e_1_3_1_26_2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0229049"},{"key":"e_1_3_1_27_2","doi-asserted-by":"publisher","DOI":"10.1017\/UPO9781922064004.009"},{"key":"e_1_3_1_28_2","doi-asserted-by":"publisher","DOI":"10.1152\/ajpheart.00439.2007"},{"key":"e_1_3_1_29_2","doi-asserted-by":"publisher","DOI":"10.1152\/physrev.1959.39.2.183"},{"key":"e_1_3_1_30_2","doi-asserted-by":"publisher","DOI":"10.1152\/physrev.00022.2020"},{"key":"e_1_3_1_31_2","doi-asserted-by":"publisher","DOI":"10.1097\/00000441-199902000-00007"},{"key":"e_1_3_1_32_2","first-page":"2372","article-title":"Comparison of static and dynamic cerebral autoregulation measurements","volume":"26","author":"Doczi TP","year":"1995","unstructured":"Doczi TP. Comparison of static and dynamic cerebral autoregulation measurements. Stroke. 1995;26:2372\u20132373.","journal-title":"Stroke"},{"key":"e_1_3_1_33_2","doi-asserted-by":"publisher","DOI":"10.3389\/fphys.2014.00234"},{"key":"e_1_3_1_34_2","doi-asserted-by":"publisher","DOI":"10.1161\/CIRCULATIONAHA.115.017308"},{"key":"e_1_3_1_35_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0735-1097(02)01719-9"},{"key":"e_1_3_1_36_2","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.2001.91.6.2493"},{"key":"e_1_3_1_37_2","doi-asserted-by":"publisher","DOI":"10.1136\/hrt.2005.069179"},{"key":"e_1_3_1_38_2","doi-asserted-by":"publisher","DOI":"10.1152\/ajpheart.00107.2022"},{"key":"e_1_3_1_39_2","doi-asserted-by":"publisher","DOI":"10.1152\/ajpheart.00138.2009"},{"key":"e_1_3_1_40_2","doi-asserted-by":"publisher","DOI":"10.1161\/HYPERTENSIONAHA.113.02824"},{"key":"e_1_3_1_41_2","doi-asserted-by":"publisher","DOI":"10.1161\/HYPERTENSIONAHA.114.04576"},{"key":"e_1_3_1_42_2","doi-asserted-by":"publisher","DOI":"10.1152\/ajpheart.00994.2011"},{"key":"e_1_3_1_43_2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0204419"},{"key":"e_1_3_1_44_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jacbts.2024.04.011"},{"key":"e_1_3_1_45_2","doi-asserted-by":"publisher","DOI":"10.5694\/mja2.50553"},{"key":"e_1_3_1_46_2","doi-asserted-by":"publisher","DOI":"10.1111\/j.1552-6569.2003.tb00158.x"},{"key":"e_1_3_1_47_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.cnp.2020.01.003"},{"key":"e_1_3_1_48_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.cnp.2021.09.001"},{"key":"e_1_3_1_49_2","doi-asserted-by":"publisher","DOI":"10.3390\/medicina58010098"},{"key":"e_1_3_1_50_2","doi-asserted-by":"publisher","DOI":"10.1007\/s10286-017-0454-2"},{"key":"e_1_3_1_51_2","doi-asserted-by":"publisher","DOI":"10.3389\/fnagi.2016.00022"},{"key":"e_1_3_1_52_2","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00637.2013"},{"key":"e_1_3_1_53_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.cnp.2018.02.004"},{"key":"e_1_3_1_54_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.ensci.2020.100276"},{"key":"e_1_3_1_55_2","first-page":"58","volume-title":"Orthostatic Symptoms and Reductions in Cerebral Blood Flow in Long\u2010Haul COVID\u201019 Patients: Similarities with Myalgic Encephalomyelitis\/Chronic Fatigue Syndrome","author":"Campen C","year":"2021","unstructured":"Campen C, Rowe PC, Visser FC. Orthostatic Symptoms and Reductions in Cerebral Blood Flow in Long\u2010Haul COVID\u201019 Patients: Similarities with Myalgic Encephalomyelitis\/Chronic Fatigue Syndrome. Medicina (Kaunas): MDPI; Medicina; 2021:58."},{"key":"e_1_3_1_56_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.eupc.2003.09.009"},{"key":"e_1_3_1_57_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.str.29.9.1876"},{"key":"e_1_3_1_58_2","doi-asserted-by":"publisher","DOI":"10.1117\/1.NPh.10.2.025013"},{"key":"e_1_3_1_59_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.cca.2016.02.009"},{"key":"e_1_3_1_60_2","doi-asserted-by":"publisher","DOI":"10.1093\/europace\/euz204"},{"key":"e_1_3_1_61_2","doi-asserted-by":"publisher","DOI":"10.4103\/2211-4122.183746"},{"key":"e_1_3_1_62_2","volume-title":"StatPearls","author":"Dhingra K","year":"2024","unstructured":"Dhingra K, Salisbury BH, Chakko MN. Doppler Extra\u2010Cranial Carotid Assessment, Protocols, and Interpretation. StatPearls. Treasure Island (FL): Ineligible Companies. Disclosure: Blake Salisbury Declares no Relevant Financial Relationships with Ineligible Companies. Disclosure: Mathew Chakko declares no relevant financial relationships with ineligible companies; 2024."},{"key":"e_1_3_1_63_2","doi-asserted-by":"publisher","DOI":"10.3389\/fcvm.2019.00171"},{"key":"e_1_3_1_64_2","doi-asserted-by":"publisher","DOI":"10.1038\/s41598-018-31685-y"},{"key":"e_1_3_1_65_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.STR.31.7.1608"},{"key":"e_1_3_1_66_2","doi-asserted-by":"publisher","DOI":"10.1093\/ajh\/hpad025"},{"key":"e_1_3_1_67_2","doi-asserted-by":"publisher","DOI":"10.1364\/BOE.10.002117"},{"key":"e_1_3_1_68_2","volume-title":"Using an Ear Device to to Monitor Blood Flow to the Head as a Dysautonomia Management Tool","author":"Lee D","year":"2023","unstructured":"Lee D, Fudim M. Using an Ear Device to to Monitor Blood Flow to the Head as a Dysautonomia Management Tool. Dysautonomic International; 2023. https:\/\/vimeo.com\/859062357."},{"key":"e_1_3_1_69_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jacep.2023.02.002"},{"key":"e_1_3_1_70_2","doi-asserted-by":"publisher","DOI":"10.1097\/CCE.0000000000000072"},{"key":"e_1_3_1_71_2","doi-asserted-by":"publisher","DOI":"10.1055\/s-0032-1331812"},{"key":"e_1_3_1_72_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jvs.2005.07.014"},{"key":"e_1_3_1_73_2","doi-asserted-by":"publisher","DOI":"10.1002\/mp.16774"},{"key":"e_1_3_1_74_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.ultrasmedbio.2019.02.010"},{"key":"e_1_3_1_75_2","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00651.2014"},{"key":"e_1_3_1_76_2","doi-asserted-by":"publisher","DOI":"10.1177\/0271678X18762880"},{"key":"e_1_3_1_77_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0301-5629(97)00077-X"},{"key":"e_1_3_1_78_2","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2012.230425"}],"container-title":["Journal of the American Heart Association"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.ahajournals.org\/doi\/full\/10.1161\/JAHA.124.036752","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,2,4]],"date-time":"2025-02-04T11:02:19Z","timestamp":1738666939000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.ahajournals.org\/doi\/10.1161\/JAHA.124.036752"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,2,4]]},"references-count":77,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2025,2,4]]}},"alternative-id":["10.1161\/JAHA.124.036752"],"URL":"https:\/\/doi.org\/10.1161\/jaha.124.036752","relation":{},"ISSN":["2047-9980"],"issn-type":[{"value":"2047-9980","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,2,4]]},"assertion":[{"value":"2024-06-07","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2024-12-19","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-02-03","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e036752"}}