Clinical and angiographic comparison of matched patients with successful directional coronary atherectomy or stent implantation for primary coronary artery lesions.

OBJECTIVES

This study was designed to compare the long-term clinical and angiographic effects of successful directional atherectomy and stent implantation and to examine whether restenosis is related to the mechanism of lumen improvement as well as the extent of lumen gain.

BACKGROUND

Directional atherectomy and coronary stent implantation have been shown to achieve a more optimal immediate result that may lead to a more favorable long-term angiographic outcome and fewer target vessel revascularizations than does angioplasty. However, it remains to be determined whether one of the devices used in these interventions provides consistently better results than the other.

METHODS

To allow meaningful comparisons a prospectively collected series of 117 patients successfully treated with atherectomy were individually matched with a prospectively collected series of 117 patients successfully treated with stent implantation. Matching for baseline characteristics identified patients with identical lesion location and lesion severity, and immediate and late angiographic and clinical outcome were compared. To evaluate the possibility of a procedure effect on restenosis, patients were further matched for both immediate angiographic outcome and baseline characteristics, providing 150 matched patients for comparison. As confirmatory analysis, multivariate models were constructed to predict late lumen diameter.

RESULTS

Matching resulted in two comparable groups with equivalent baseline clinical and stenosis characteristics (n = 117 pairs). Atherectomy led to a smaller immediate gain than stenting and, because late loss was similar in both groups, stenting resulted in a larger late lumen (1.96 +/- 0.51 vs. 1.66 +/- 0.55 mm, p < 0.0001). When patients were matched for immediate gain and baseline characteristics (n = 75 pairs), lumen loss was more pronounced after atherectomy, and thus the minimal lumen diameter at follow-up differed significantly between the two groups (1.66 +/- 0.53 vs. 1.90 +/- 0.47 mm, p = 0.004). This beneficial angiographic effect of stenting was accompanied by a reduced need for repeat interventions. Multivariate analysis confirmed the independent effect of the interventional device used, whereby less loss and greater lumen diameter at follow-up were predicted for stent implantation than for atherectomy.

CONCLUSIONS

Successful stent implantation provided a more favorable long-term angiographic outcome and lower rates of restenosis and need for target lesion revascularization than did atherectomy. This favorable effect of stenting not only is related to a larger, immediate gain, but also seems to attenuate late lumen loss.