Effect of Guglielmi detachable coil placement on intraaneurysmal pressure:Experimental study in canines

BACKGROUND AND PURPOSE: Treatment of ruptured aneurysms with Guglielmi deta chable coils (GDCs) has been shown to prevent repeat bleeding. To assess wh ether GDC coiling alters aneurysmal pressure, we measured intraaneurysmal p ressure in two canine types of carotid artery aneurysms before and after GD C placement. METHODS: A 0.014-inch guidewire with a pressure transducer was inserted int o parent arteries and domes of surgically created aneurysms. Intravascular static pressures were recorded before and during saline power injections (1 0, 20, and 30 mL over 1 and 2 s), before and after GDC placement. Common fe moral arterial pressure was monitored. RESULTS: Saline power injections reproducibly and abruptly increased pressu re in parent arteries and aneurysms. Mean intraaneurysmal pressure varied ( 18 +/- 4 [10 mL] to 75 +/- 15 mm Hg [30 mL]), independent of injection dura tion. Intraaneurysmal baseline pressures were higher after GDC placement (1 11 +/- 10 versus 93 +/- 15 mm Hg; P =.05). Aneurysmal pressure increases wi th saline injections were slightly higher after GDC placement, which dampen ed intraaneurysmal pressure amplitude at baseline (26.5 +/- 5.6 versus 19.6 +/- 7.4 mm Hg; P = .003) and during hypertension (25.3 +/- 5.4 versus 19.8 +/- 7.5 mm Hg, P = .002). The pressure increase slope with saline injectio n was delayed with GDC placement (0.24 +/- 0.1 versus 0.38 +/- 0.19 s; P < .001). CONCLUSION: Graded saline power injections into parent arteries can rapidly increase intraaneurysmal pressure. GDC treatment did not attenuate mean in traaneurysmal pressures, but both dampened the pressure amplitude and delay ed pressure increases during locally induced hypertension.