High speed rotational atherectomy for diffuse in-stent restenosis: short- and mid-term follow-up results

Between January 1997 to May 1998, 37 consecutive patients underwent high speed rotational atherectomy with adjunctive balloon angioplasty for the management of first-time diffuse variety of in-stent restenosis in the native coronary arteries. Their age ranged from 38 to 71 years (mean 54.3 +/- 9.7 years). All the patients underwent initial stent implantation at moderate to high pressure. Patients were either symptomatic or demonstrated significant ischaemia by non-invasive testing. The median time from the index procedure to in-stent restenosis was 20 weeks (range 9-40 weeks). Majority (78.1%) of lesions were in the territory of left anterior descending coronary artery. The mean lesion length was 24.3 +/- 8.3 mm (range 12-42 mm). Five lesions each (12.2%) were total occlusion and ostial in location. High speed rotational atherectomy was performed using stepped burr technique in majority (90.2%) with the largest burr corresponding to approximately 70 percent of the reference vessel diameter. The initial burr size ranged from 1.5-2.0 mm, final burr was 1.75-2.25 mm and the average number of burrs used per target vessel was 2.2 +/- 0.3 (range 1-3). Adjunctive balloon angioplasty was performed in all (100%) cases using a semi-compliant oversized balloon (balloon-to-artery ratio 1.1:1) inflated at a pressure of 6.5 +/- 2.1 atmospheres (range 4-10). The procedure was successful in all cases without any major complications (death, Q-MI, CABG or repeat PTCA). Over a median follow-up of 10 months, 27 (73%) patients were asymptomatic. Recurrence of clinical events occurred in 10 (27%) patients at median interval of 16 weeks after rotational atherectomy. Angina was controlled on drug therapy in six (16.2%) and target vessel revascularisation was required in three (8.1%) cases. By the Kaplan-Meier estimate, an event-free survival (absence of death, Q-MI, recurrence of angina, target vessel revascularisation) was 97.3, 94.6, 75.7 and 72.6 percent at 1, 3, 6 and 12 months, respectively. Thus, rotational atherectomy using a stepped burr approach for adequate debulking, followed by adjunctive balloon angioplasty is safe with excellent in-hospital results for the treatment of diffuse in-stent restenosis. Although recurrence of symptoms develops in approximately one-fourth of patients on follow-up, it is much less than reported with balloon angioplasty in this subgroup of patients.