Symptomatic autoregulatory failure in acute ischemic stroke

A 50-year-old man with a history of long-standing untreated hypertension developed sudden-onset throbbing headache and right-sided weakness. When he sought medical attention 2 days later, his blood pressure was 183/110 mm Hg (mean arterial pressure [MAP] 134), and he had word-finding difficulties, dyscalculia, and slow fine finger movements on the right. MRI showed old bilateral deep white matter border zone infarcts (“string of pearls”), an old right frontal border zone infarct, and a new left posterior temporal-occipital border zone infarct (figure, A). Carotid Doppler ultrasound scan showed less than 50% stenosis of the cervical carotid arteries. A transthoracic echocardiogram showed left ventricular dysfunction with an ejection fraction of 33% and an apical mural thrombus. During his first two hospital days, MAP as determined by blood pressure cuff ranged from 103 to 127 mm Hg on no antihypertensive medications. He underwent a PET scan on the second hospital day, 4 days after stroke onset. Cerebral blood flow (CBF) measurements and reduction in MAP with nicardipine were carried out as previously described.¹ Three baseline measurements of bihemispheric (hCBF) and regional CBF in the 12.5-mm (six pixels) rim surrounding the infarct (rCBF) were …