Prevention of carotid angioplasty-induced bradycardia and hypotension with temporary venous pacemakers.

OBJECTIVE: Carotid angioplasty with stent placement is becoming an established treatment modality for patients with high-risk carotid stenosis. Unlike carotid endarterectomy, angioplasty causes direct mechanical dilation of the stenotic carotid artery and bulb. Stimulation of the sinus baroreceptors induces a reflexive response that consists of increased parasympathetic discharge and inhibition of sympathetic tone, which results in bradycardia and subsequent cardiogenic hypotension. METHODS: At a single institution, the experience with 43 patients treated from November 1994 to January 2000 with 47 angioplasty and stent procedures for occlusive carotid artery disease was retrospectively reviewed. Prophylactic temporary venous pacemakers were used to prevent hypotension from possible angioplasty-induced bradycardia. Pacemakers were set to capture a heart rate decrease below 60 beats per minute. Variables analyzed included demographics, etiology of disease, side of the lesion, the presence of symptoms, history of coronary artery disease, percent stenosis, type of stent used, number of dilations, pressure of dilation, and angioplasty balloon diameter. RESULTS: Ten patients were excluded because pacemakers were not used during their angioplasty procedures, and these included three emergencies and a lesion that was unrelated anatomically to the carotid sinus (petrous carotid). The remaining 37 procedures were performed in 33 patients with a mean age of 67 years, and consisted of 17 men, 16 women, 20 right and 17 left-sided lesions. The pacemakers maintained a cardiac rhythm in 23 (62%) of the 37 procedures and in no case did the pacemaker fail to respond when activated. Recurrent (56%; 10 of 18), radiation-induced (78%; 7 of 9), and medically refractory carotid stenosis (67%; 6 of 9) required intraprocedural pacing. Two patients with recurrent stenosis became hypotensive despite the aid of the pacing device but were not symptomatic. Seventy-nine percent (15 of 19) of symptomatic lesions and 57% (8 of 14) of nonsymptomatic lesions required pacing, which was statistically significant (P = 0.049). No patient experienced an operative morbidity or mortality as a consequence of the temporary pacing devices. CONCLUSION: Angioplasty-induced bradycardia is a common condition, and it is more prevalent in radiation-induced stenosis and with symptomatic lesions. Temporary venous demand pacing is a safe procedure and may prevent life-threatening, baroreceptor-induced hypotension.

Assessment of acutely unsuccessful attempts at detachable coiling in intracranial aneurysms.

OBJECTIVE: Guglielmi detachable coiling (GDC) has quickly become the most common endovascular method for the treatment of intracranial aneurysms. Although several published case series describe various authors' successful experiences or complications, few have elaborated on failed attempts. We examined our experience with GDC, and we analyzed all failed attempts at coiling. METHODS: Patients who underwent endovascular procedures from September 1995 through July 1999 were identified using endovascular case logs and billing records. Patient charts were then reviewed retrospectively for failed attempts at GDC. A treatment failure was defined as an inability to place coils into an aneurysm, a GDC procedure-related complication resulting in death, or an acute rehemorrhage from a coiled aneurysm that indicated a failure of coils to prevent rerupture. Thromboembolic events and other nonfatal sources of morbidity that did not preclude coiling of the aneurysm were analyzed only to the extent that they prevented successful coiling of the aneurysm. RESULTS: From September 1995 to June 1999, 241 patients underwent GDC embolizations or attempts. In these patients, 35 procedures were unsuccessful, including 7 deaths from intraoperative or postoperative aneurysmal rerupture. Sixteen aneurysms could not be microcatheterized, nine of which were anterior communicating artery aneurysms. Coils from 13 wide-necked aneurysms (average fundus-to-neck ratio, <2) prolapsed into the parent vessel. Three procedures were abandoned when the aneurysms were found to have normal branches filling from the dome, and three additional procedures were abandoned for technical reasons. Five deaths resulted from intraoperative aneurysm rupture, and two patients died postoperatively from rerupture. CONCLUSION: The number of successful coiling procedures has increased with experience and improved technology. The procedure still involves risks, however, primarily for patients with subarachnoid hemorrhage.

Therapeutic modalities for the management of cerebral vasospasm: timing of endovascular options.

OBJECTIVES: To determine if a window of time could be defined during which angioplasty would be most effective in reversing neurological decline and ultimately improving outcome. METHODS: Of a group of 466 patients, 93 underwent endovascular management of clinical vasospasm that was medically refractory. Eighty-four of the 93 patients were available for follow-up for at least 6 months. All patients underwent mechanical angioplasty using compliant microballoon systems and, if distal spasm was present, the administration of papaverine. RESULTS: Fifty-one patients underwent endovascular management within a 2-hour window, and 33 patients underwent treatment more than 2 hours after the development of their symptoms. Compared with the group treated more than 2 hours after neurological decline (P < 0.01; chi2 = 8.02), the group that underwent endovascular management within a 2-hour window after the development of symptoms demonstrated sustained clinical improvement. CONCLUSION: When a patient develops symptomatic vasospasm and is unresponsive to traditional measures of critical care management, angioplasty may be effective in improving the patient's neurological status if this procedure is performed as early as possible. The results indicate that a 2-hour window may exist for restoration of blood flow to ultimately improve the patient's outcome.

Carotid angioplasty and stenting for recurrent and radiation-induced stenosis: preliminary experience.

Carotid endarterectomy for atherosclerotic occlusive disease has become the standard of care for the treatment of symptomatic and asymptomatic occlusive disease of the carotid bifurcation, based on the results of the North American Symptomatic Carotid Endarterectomy Trial, as well as the Asymptomatic Carotid Atherosclerosis Study. For surgical treatment to be of benefit, the perioperative complication rate for neurological events should be 6% or less in the symptomatic population and 3% or less in the asymptomatic group. The performance of carotid endarterectomy for recurrent stenosis and radiation-induced stenosis has reported neurological events ranging from 4 to 10%. It is in this particular population that carotid angioplasty and stent placement may play a role. The authors performed a retrospective analysis of 11 patients who underwent carotid angioplasty and stent placement for recurrent or radiation-induced stenosis. One patient in whom endarterectomy was performed by the vascular surgery service had a critical stenosis distal to the endarterectomy site and awoke with a neurological deficit. This patient underwent reexploration and placement of a stent in the artery distal to the arteriotomy site. The follow-up period ranged from 7 to 12 months. Patient age ranged from 65 to 77 years (mean 75 years). Five of eight patients underwent angioplasty and stent placement for recurrent atherosclerotic disease. Two patients had radiation-induced stenosis, and one patient had a stent placed intraoperatively. All patients, with the exception of the one who underwent intraoperative stent placement, had posttreatment stenoses of less than 15%. The surgical patient had a 30% residual stenosis distally. There were no intra- or postoperative transient ischemic attacks, major or minor strokes, or deaths. Patients who have recurrent or radiation-induced stenosis are potential candidates for angioplasty and stent placement. Before this can be recommended as an alternative to surgical correction, a longer follow-up period is required.