Date Published: March 11, 2019
Publisher: Public Library of Science
Author(s): Mahesh Kate, Laura Gioia, Thomas Jeerakathil, Michael D. Hill, Bronwen Gould, Rebecca McCourt, Dar Dowlatshahi, Shelagh Coutts, Jayme Kosior, Andrew Demchuk, Brian Buck, Kenneth Butcher, Terence J. Quinn.
Leukoaraiosis regions may be more vulnerable to decreases in cerebral perfusion. We aimed to assess perfusion in leukoaraiosis regions in acute intracerebral hemorrhage (ICH) patients. We tested the hypothesis that aggressive acute BP reduction in ICH patients is associated with hypoperfusion in areas of leukoaraiosis. In the ICH Acutely Decreasing Arterial Pressure Trial (ICH ADAPT), patients with ICH <24 hours duration were randomized to two systolic BP (SBP) target groups (<150 mmHg vs. <180 mmHg). Computed tomography perfusion (CTP) imaging was performed 2h post-randomization. Leukoaraiosis tissue volumes were planimetrically measured using semi-automated threshold techniques on the acute non-contrast CT. CTP source leukoaraiosis region-of-interest object maps were co-registered with CTP post-processed maps to assess cerebral perfusion in these areas. Seventy-one patients were included with a mean age of 69±11.4 years, 52 of whom had leukoaraiosis. The mean relative Tmax (rTmax) of leukoaraiotic tissue (2.3±2s) was prolonged compared to that of normal appearing white matter in patients without leukoaraiosis (1.1±1.2s, p = 0.04). In the 52 patients with leukoaraiosis, SBP in the aggressive treatment group (145±20.4 mmHg, n = 27) was significantly lower than that in the conservative group (159.9±13.1 mmHg, n = 25, p = 0.001) at the time of CTP. Despite this SBP difference, mean leukoaraiosis rTmax was similar in the two treatment groups (2.6±2.3 vs. 1.8±1.6 seconds, p = 0.3). Cerebral perfusion in tissue affected by leukoaraiosis is hypoperfused in acute ICH patients. Aggressive BP reduction does not appear to acutely aggravate cerebral hypoperfusion.
Recent studies suggest leukoaraiosis is an independent predictor of worse short and long-term outcomes in intracerebral hemorrhage (ICH), including increased early mortality rates.[1–4] The mechanisms of leukoaraiosis associated poor outcomes are unknown, but may be related to increased ICH volume and/ or expansion at presentation. Most concerning, and relevant to acute blood pressure management, is the fact that sub-acute ischemic lesions appear to be associated with leukoaraiosis, raising the possibility that these patients are more hemodynamically susceptible to perfusion changes.
This study demonstrates that cerebral perfusion is hypoperfused in the leukoaraiosis regions in acute ICH patients. Although cerebral perfusion is lower in patients with leukoaraiosis, this does not appear to be affected differentially by acute blood pressure reduction, relative to patients without leukoaraiosis.
BP reduction remains controversial in ICH, but we found no evidence in our study that patients with chronic leukoaraiosis should be treated any differently. This is important, as leukoaraiosis is common in ICH patients, both of which result from small vessel disease.