Can ischemic stroke be caused by acute reduction of blood pressure in the acute phase of cardiovascular disease?

Acute-phase cardiovascular disease (CVD) frequently presents with markedly elevated blood pressure (BP) levels and often requires fairly rapid lowering of BP. On the other hand, aggressive lowering of systemic BP to the point that the cerebral BP decreases below a certain threshold may result in ischemic stroke. The authors retrospectively studied 192 consecutive patients with CVD who had markedly elevated BP and end-organ damage. Ischemic stroke was noted in 12 of these patients during BP-lowering therapy. The incidence of ischemic stroke did not differ significantly between a standard BP-lowering group, in which the target BP reduction was within the parameters of the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure guidelines, and a rapid BP-lowering group, in which the target BP was below these guidelines (7.1% vs 2.6%, respectively; P=.27, not significant). In stepwise multiple regression analysis, diabetes mellitus (beta=0.203, P=.008) and acute pulmonary edema (beta=0.228, P=.003) remained significant factors associated with the incidence of stroke. Thus, acute pulmonary edema and diabetes were the most important factors related to ischemic stroke during BP reduction in patients with marked elevations of BP regardless of the rapidity of BP lowering.