A 7-year experience with balloon-mounted coronary stents for the treatment of symptomatic vertebrobasilar intracranial atheromatous disease

Abstract

Objective: Balloon-mounted coronary stents (BMCS) have been adapted for use in the intracranial circulation for the treatment of symptomatic intracranial atheromatous disease (ICAD). We performed a retrospective analysis of our 7-year experience with these devices in an attempt to quantify the periprocedural risks and long-term outcomes in patients with symptomatic ICAD of the vertebrobasilar (VB) system treated with BMCS.

Methods: A retrospective review of a prospectively maintained database was performed to determine the neurological and non-neurological periprocedural risks of BMCS treatment of ICAD. Patients were followed with serial transcranial Doppler (TCD) and, in some cases, angiographic imaging. The clinical status was determined based on clinic visits and by telephone interviews when possible.

Results: Over the 6-year period from March 1999 to May 2005, 44 patients (35 men, 9 women; average age, 64.8 yr) with 47 symptomatic atheromatous lesions of the VB system were treated with BMCS. In two patients, the BMSC could not be delivered across the target lesion. Treatment of the remaining 45 lesions was technically successful (95.7%). The periprocedural neurological morbidity and mortality was 26.1% (10 clinically evident strokes, 2 deaths). One additional patient experienced a periprocedural transient ischemic attack (TIA). Two patients died of non-neurological causes within 6 months (4.3%, myocardial infarction and cholecystitis). The average stenosis measured 82.5%, declining to 10.0% stenosis after BMCS. TCD examinations showed a preprocedural velocity of 127.7 cm/second (n = 43; standard deviation, 63.7 cm/s), which declined to 54.0 cm/s immediately after the procedure (n = 42; standard deviation, 22.7 cm/s). In patients with serial TCD evaluations, velocities were typically constant over years of follow-up (six patients with >5 yr of follow-up; average velocity, 52.2 cm/s). Angiographic follow-up was available for 11 patients. Three patients had stent occlusion (all symptomatic with TIAs), one patient had greater than 50% in-stent restenosis (ISR) (symptomatic with TIA) and seven had no significant (<50%) stenosis. The overall ISR/occlusion rate was 12.5% (4 out of 32 lesions with angiographic and/or TCD follow-up > 6 mo). Of the 42 patients who successfully underwent BMCS, clinical follow-up was available for 33 (78.6%, average follow-up period, 43.5 mo), three patients died before any follow-up could be performed, and seven were lost to follow-up. Of the patients with follow-up, five had recurrent vertebrobasilar ischemic symptoms (15%; four TIA, one stroke). Four out of five patients with recurrent symptoms had ISR or occlusion verified on conventional angiography. At the time of the last follow-up examination, seven patients of 44 patients who underwent attempted treatment were dead (modified Rankin Scale [mRS] score, 6); four had an mRS score of 3 to 5, 16 had an mRS score of 1 or 2, and 10 had an mRS score of 0.

Conclusion: Percutaneous transluminal angioplasty and stenting using BMCS for the treatment of symptomatic VB ICAD can be carried out with high rates of technical success and excellent immediate angiographic results. However, the procedure carries with it a very high rate of periprocedural morbidity and mortality. Greater than 50% ISR or stent occlusion occurred in 12.5% of the patients and was associated with recurrent TIAs. In the absence of ISR/occlusion, patients who tolerated the initial procedure did well neurologically and did not typically experience recurrent ischemic symptoms.