Selective intraarterial nimodipine treatment in an experimental subarachnoid hemorrhage model.
OBJECTIVE
Cerebral vasospasm secondary to subarachnoid hemorrhage (SAH) has been a serious clinical problem. The aim of the present study is to evaluate the efficacy of selective intraarterial (IA) nimodipine treatment in a rabbit model of chronic cerebral vasospasm.


METHODS
Twenty-two adult New-Zealand rabbits of either sex, weighing 2500-3800 g were used for this study. Following a control angiography, all animals received 1 mL of fresh unheparinized autologuous arterial blood into the cisterna magna. Three days later, the presence of vasospasm was demonstrated angiographically by selective vertebral artery injection. The experimental design was as follows: separate groups of animals (n = 5, in each group) received nimodipine (0.05 mg/kg), papaverine (6 mg/kg), or vehicle intraarterially, after placement of a microcatheter into the vertebral artery. Another group (n = 5) received nimodipine (0.05 mg/kg) directly into the cisterna magna, and vehicle injection was made into cisterna magna in two other animals. Thirty minutes after treatment, angiographies were repeated and changes in arterial diameter were expressed as percentages of control.


RESULTS
IA nimodipine and IA papaverine were effective in relieving veretebral and basilary vasospasm (P < .05). IA nimodipine was more effective than IA papaverine (P < .05). IA nimodipine was not more effective than intrathecal (IT) nimodipine in relieving vertebral artery vasospasm, although it was more effective than IT nimodipine in basilar artery. Vehicle injections (IA or IT) failed to reverse the vasospasm induced by autologuous blood injection.


CONCLUSIONS
This study showed that selective IA nimodipine treatment may be considered as an alternative in the treatment of chronic vasospasm following SAH.
Firat
M Murat
MM
Department of Radiology, Faculty of Medicine, Hacettepe University, Ankara, Turkey.
Gelebek
Veli
V
Orer
Hakan S
HS
Belen
Deniz
D
Firat
Ahmet K
AK
Balkanci
Ferhun
F
D000818:Animals; D002121:Calcium Channel Blockers / Q000008:administration & dosage*; D004195:Disease Models, Animal; D005260:Female; D007269:Injections, Intra-Arterial; D008297:Male; D009553:Nimodipine / Q000008:administration & dosage*; D011817:Rabbits; D013345:Subarachnoid Hemorrhage / Q000150:complications / Q000188:drug therapy*; D020301:Vasospasm, Intracranial / Q000188:drug therapy* / Q000209:etiology
D002121:Calcium Channel Blockers; D009553:Nimodipine