A case of vertebral artery dissection associated with morning blood pressure surge.

We report a case of a middle-aged man who suffered a cerebral infarction resulting from dissection of a vertebral artery associated with morning blood pressure surge. A 56-year-old man was transferred to our hospital with dizziness and vomiting in the early morning on a cold day in winter. He reported that he had been standing in front of the sink after bathing when he suddenly felt dizzy and fell down. He did not lose consciousness, and by the time he reached the hospital by ambulance, his dizziness had subsided, but he complained of severe headache and vomited 3 times. On admission, he was alert, and there were no neurological or radiological abnormalities (CT, MR angiography) in the brain. However, infarction in the left cerebellar hemisphere was detected by brain MRI on the 5th day of hospitalization. String sign of the left vertebral artery was noted by angiography, confirming the diagnosis of dissection of the left vertebral artery. Ambulatory blood pressure monitoring was performed after discharge. Although the mean 24-h blood pressure was in the normal range, a marked morning blood pressure rise was observed. We speculated that the acute rise of blood pressure in the early morning might have contributed to the dissection of the vertebral artery.