The relationship and threshold of stent length with regard to risk of stent thrombosis after drug-eluting stent implantation.

OBJECTIVES

The aim of this study was to evaluate the association between the length of the stented segment and the risk of stent thrombosis (ST) after drug-eluting stent (DES) implantation and to determine the cutoff value of stent length in higher risk of ST in routine clinical practice.

BACKGROUND

Despite the recommendations of full lesion coverage to prevent angiographic restenosis, the length of the stented segment has been a risk factor for DES-related ST.

METHODS

A total of 3,145 consecutive patients (4,667 lesions) who underwent DES implantation were analyzed. The independent association of stent length with ST and its predictive value were evaluated for a median 29.6 months (interquartile range 21.6 to 37.5 months).

RESULTS

Stent thrombosis occurred in 68 patients (2.2%) at 3 years. The stent length/lesion was an independent predictor of ST (hazard ratio: 1.11, 95% confidence interval: 1.06 to 1.15, p < 0.001). The threshold of stent length for predicting ST was 31.5 mm (area under the receiver-operating characteristic curve: 0.746, 95% confidence interval: 0.699 to 0.793, p < 0.001), which had a sensitivity and specificity of 88.4% and 52.1%, respectively. Stent lengths >or=31.5 mm were associated with higher rates of ST (4.0% vs. 0.7%, p < 0.001), death (5.2% vs. 3.0%, p = 0.005), and myocardial infarction (2.4% vs. 0.7%, p = 0.001) at 3 years, as compared with stent lengths <31.5 mm.

CONCLUSIONS

Length of the stented segment was independently associated with the incidence of ST and death or myocardial infarction after DES implantation. The value of stent length >or=31.5 mm is a threshold for the prediction of ST.