The lower safety level of blood pressure evaluated by ¹²³I-IMP single-photon emission computed tomography in acute cerebral infarction patients

Aims: At the acute phase of cerebral infarction, the autoregulation of cerebral blood flow (CBF) is compromised. In this study, we explored the lower safety level of blood pressure (BP) for maintaining optimal CBF in acute cerebral infarction patients. Patients & methods: Acute middle cerebral artery territorial infarctions were screened. Patients who had single-photon emission computed tomography performed within 7 days following onset were enrolled (n = 30). The CBF ratio (ischemic:intact) was calculated at the border zone of the middle cerebral artery. Vascular lesions were assessed by magnetic resonance angiography. Results: The lowest BP level that maintained the CBF ratio ≥0.6 was 109 mmHg in patients with mild-to-moderate stenosis and 142/79 mmHg in patients with occlusion at the lesion side and stenosis at the intact side by the linear regression analysis. Conclusion: BP control should be carefully managed in acute stroke patients with occlusion and stenosis in the main arteries of the brain.