Injury of the afferent limb of the baroreflex from neck radiation causes radiation-induced afferent baroreflex failure (R-ABF). Identification and management of R-ABF is challenging. We aimed to investigate the pattern of autonomic dysfunction on standardized autonomic testing in patients with probable R-ABF. We retrospectively analyzed all autonomic reflex screens performed at Mayo Clinic in Rochester, MN, between 2000 and 2020 in patients with probable R-ABF. Additional tests reviewed included ambulatory blood pressure monitoring, plasma norepinephrine, and thermoregulatory sweat test. We identified 90 patients with probable R-ABF. Median total composite autonomic severity score (range, 0–10) was 7 (interquartile range, 6–7). Cardiovascular adrenergic impairment was seen in 85 patients (94.4%), increased blood pressure recovery time after Valsalva maneuver in 71 patients (78.9%; median 17.4 seconds), and orthostatic hypotension in 68 patients (75.6%). Cardiovagal impairment was demonstrated by abnormal heart rate responses to deep breathing (79.5%), Valsalva ratio (87.2%), and vagal baroreflex sensitivity (57.9%). Plasma norepinephrine was elevated and rose appropriately upon standing (722–1207 pg/mL). Ambulatory blood pressure monitoring revealed hypertension, postural hypotension, hypertensive surges, tachycardia, and absence of nocturnal dipping. Blood pressure lability correlated with impaired vagal baroreflex function. Postganglionic sympathetic sudomotor function was normal in most cases; the most frequent thermoregulatory sweat test finding was focal neck anhidrosis (78.9%). Standardized autonomic testing in R-ABF demonstrates cardiovascular adrenergic impairment with orthostatic hypotension, blood pressure lability, and elevated plasma norepinephrine. Cardiovagal impairment is common, while sudomotor deficits are limited to direct radiation effects.
Healthcare Worker With Large Vessel Acute Ischemic Stroke Likely Related to Mild SARS-CoV-2 Infection
We report the case of a healthcare worker who presented with a large vessel acute ischemic stroke in setting of a mild SARS-CoV-2 infection and provide a review of the emerging literature on COVID-related stroke. A 43-year-old female presented with right-sided hemiparesis, aphasia and dysarthria. She had a nonproductive of cough for 1 week without fever, fatigue or dyspnea. A CT Head, CT angiography and CT perfusion imaging revealed a M1 segment occlusion of the left middle cerebral artery requiring transfer from a primary to a comprehensive stroke center. A nasopharyngeal swab confirmed SARS-CoV-2 infection prior to arrival at the accepting center. During the thrombectomy a 3 cm thrombus was removed. Thrombus was also evident in the 8 French short sheath during closure device placement so a hypercoagulable state was suspected. Stroke work-up revealed a glycosylated hemoglobin of 8.7%, elevation of inflammatory markers and an indeterminate level of lupus anticoagulant IgM. On discharge home, she had near complete neurological recovery. This case highlights suspected mechanisms of hypercoagulability in SARS-CoV-2 infection and the importance of optimizing stroke care systems during the COVID-19 pandemic.