Head-down tilt 15° increases cerebral perfusion before recanalization in acute ischemic stroke. A pre-clinical MRI study.
Beretta S., Carone D., Cho T-H., Viganò M., Diamanti S., Mariani J., Pedrazzini FA., Bianchi E., Pini C., Bolbos R., Wiart M., Ferrarese C., Chauveau F.
We investigated the therapeutic effect of head-down tilt at -15° (HDT15) on cerebral collateral flow and early infarct growth in a rat model of large vessel occlusion stroke, using multi-modal MRI. Endovascular occlusion of the proximal middle cerebral artery was induced for 90 min in Wistar rats (n = 28), followed by reperfusion. Rats were randomly assigned to HDT15 or flat position for 60 min, starting 30 min after occlusion. Multi-modal brain MRI, including perfusion, angiographic and structural sequences were acquired before treatment, after 60 min of treatment and 24 h after reperfusion. The primary outcome was change in cerebral perfusion after the 60-min treatment, assessed by time-to-peak (rTTP), adjusted for baseline collateral score. The secondary outcome was infarct growth in the first 24 h. The perfusion shift analysis, comparing post- versus pre-treatment changes in time-to-peak maps, showed a significant increase in cerebral perfusion in the HDT15 group (common odds ratio 1.50; 95 % CI 1.41-1.60; p