Ge. Sviri et al., Brain natriuretic peptide and cerebral vasospasm in subarachnoid hemorrhage - Clinical and TCD correlations, STROKE, 31(1), 2000, pp. 118-122
Background ann Purpose-Hyponatremia has been shown in association with cere
bral vasospasm (CVS) following aneurysmal subarachnoid hemorrhage (SAH). In
the past few years there has been increasing evidence that brain natriuret
ic peptide (BNP) is responsible for natriuresis after SAH, The purpose of t
he present study was to investigate the relationship between BNP plasma con
centrations and CVS after aneurysmal SAH.
Methods-BNP plasma concentrations were assessed at 4 different time periods
(1 to 3 days, 4 to 6 days, 7 to 9 days, and 10 to 12 days) in 19 patients
with spontaneous SAH. BNP plasma levels were investigated with respect to n
eurological condition, SAH severity on CTI and flow velocities measured by
means of transcranial Doppler.
Results-Thirteen patients had Doppler evidence of CVS; 7 of these had nonsy
mptomatic CVS. In 6 patients, CVS was severe and symptomatic, with delayed
ischemic lesion on CT in 5 of these. CVS was severe and symptomatic in 6 pa
tients, and delayed ischemic lesions were revealed on CT in 5 of these. BNP
levels were found to be significantly elevated in SAH patients compared wi
th control subjects (P=0.024). However, in patients without CVS or with non
symptomatic CVS, BNP concentrations decreased throughout the 4 time periods
, whereas a 6-fold increase was observed in patients with severe symptomati
c CVS between the first and the third periods (P=0.0096). A similar trend i
n BNP plasma levels was found in patients with severe SAH compared with tho
se with nonvisible or moderate SAH (P=0.015).
Conclusions-In conclusion, our results show that BNP plasma levels are elev
ated shortly after SAH, although they increase markedly during the first we
ek in patients with symptomatic CVS. The present findings suggest that secr
etion of BNP secretion after spontaneous SAH may exacerbate blood flow redu
ction due to arterial vasospasm.