Procedural and follow up results with a new balloon expandable stent in unselected lesions.

OBJECTIVE

To assess the clinical and angiographic results of the first clinical application of a new balloon expandable stent, the NIR stent, characterised by high longitudinal flexibility and low profile before expansion, and by high radial support and minimal recoil and shortening after expansion.

DESIGN

Single centre survey of unselected lesions in consecutive patients.

SETTING

Tertiary referral centre. PATIENTS AND LESIONS: 93 stents of various length (9, 16, and 32 mm) were implanted in 64 lesions in 41 patients. Twenty lesions (31%) were longer than 15 mm, and 17 lesions (27%) were located in vessels with a diameter smaller than 2.5 mm. Extreme tortuosity of the proximal vessel was present in 15 lesions (23%). All patients were treated with aspirin and ticlopidine. All lesions were evaluated before and after treatment by quantitative angiography, and in 47 lesions (75%) the stent expansion was also controlled by intracoronary ultrasound. Clinical follow up was available in all patients and angiographic follow up was performed in 53 lesions (84%), at a mean (SD) interval of 5.4 (1.7) months.

RESULTS

Deployment of the stent failed in two lesions (3%). Minimum lumen diameter increased from 1.01 (0.54) mm to 2.94 (0.49) mm, and diameter stenosis decreased from 66(15)% to 7(11)%. There was one in-hospital non-Q wave myocardial infarction, one sudden death after 40 days, and 17 target lesion revascularisations (27%). Angiographic restenosis (> or = 50% diameter stenosis) was documented in 19 lesions (36% of all lesions with angiographic follow up), with an average residual diameter stenosis of 43(21)% and minimum lumen diameter of 1.63 (0.74) mm. Restenosis was more common in vessels with a reference diameter < 2.5 mm (45%) and for lesions longer than 15 mm (46%).

CONCLUSIONS

The NIR stent could be used successfully in most lesions, achieving optimal angiographic results with very few in-hospital or subacute cardiac events. The angiographic restenosis rate and need for target lesion revascularisation remained high in this unfavourable lesion subset, especially in small vessels and long lesions.