ANGIOPLASTY OF VASOSPASM - IS IT REASONABLE

Clinical and radiographic examinations indicate preliminarily indicati ons that transluminal angioplasty may be effective in overall manageme nt of the patient with vasospasm. Many questions remain, including: Ho w does it work?; Are the effects persistent!; Is the arterial wall inj ured by the process? Recent studies in several patients who died after angioplasty allow us to provide some answers. Undilated spastic arter ies show proliferation of both cellular and connective tissue elements . There is good evidence that myofibroblasts have reorganized the coll agen framework, increasing fibril density and thus thickness. Dilated vessels show thinning of the arterial wall without disruption but with compaction of the new collagen fibrils. Cellular nests are also compr essed and stretched. The endothelial layers are undisturbed. The succe ss of dilatation depends on the amount and location of proliferation p resent. The effect is usually permanent. Because our protocols call fo r dilatation no greater than 10% above normal diameter, the muscle lay ers have not been torn or stretched although focal areas of necrosis a re sometimes seen. Understanding the constrictive process and its reli ef through dilatation, allows us to formulate a therapeutic plan. Our experience in treating 89 patients with vasospasm after SAH suggests t hat, for best results, angioplasty should be performed before the angi opathic features become florid. This helps to preserve flow through th e short arteries to the brain stem and deep brain nuclei, which may be involved indirectly in the vasospastic process.