Abstract
Twenty-three patients who developed an acute stroke during hospitalization in our clinic from 1971 to 1983 were retrospectively studied. Of those, 16 cases were of cerebral infarction and 7 of hemorrhagic stroke. Complete clinical data before and after stroke, including daily or frequent blood pressure measurements, hematology and blood chemistry were available in 12 cases of cerebral thrombosis (6 hypertensives and 6 normotensives). Our own criteria, described elsewhere, were used for diagnosis of hypertension. In 4 of the 6 hypertensives, a marked reduction of the blood pressure, ranged from 33 to 69 mmHg in mean arterial blood pressure, following antihypertensive treatment was observed before the occurrence of cerebral thrombosis. On the other hand, the blood pressure changed little in all normotensive patients except one who had congestive heart failure.
It had been known that cerebral autoregulation in hypertensive patients is adapted to a high blood pressure and its lower limit is shifted upwards. Therefore longstanding or severe hypertensive patients may be at risk to develop cerebral ischemia even at the blood pressure that is well tolerated by normotensive subjects. Our present results suggest that a considerably rapid and marked lowering of the blood pressure by antihypertensive treatment in hypertensives is one of the important factors for developing cerebral thrombosis.
