Clinical Outcome of Stent Implantation in Small Coronary Arteries
Clinical Outcome of Stent Implantation in Small Coronary Arteries
Purpose. We evaluated the results of stent placement in small coronary arteries.
Subjects. The subjects were divided into 2 groups: the first contained 911 lesions treated with stenting in the coronary arteries (stent group), and the second contained 1,203 background- and patient-matched lesions treated with balloon angioplasty (POBA group). There was no significant difference in the background of patients or lesions between the groups. A "small coronary artery" was defined as a coronary artery with a reference vessel diameter < 3.0 mm.
Results. There was no significant difference in incidence of acute myocardial infarction (AMI), coronary artery bypass grafting, or death between the groups. In the stent group, acute occlusion (0.8%) and subacute thrombosis (2.1%) occurred. The restenosis rate of 29.8% in the stent group was significantly lower than in the POBA group (38.2%; p < 0.01). The restenosis rate of 19.4% in stented vessels > 3.0 mm diameter was significantly lower than in vessels < 3.0 mm diameter (29.8%; p < 0.01). The rate of restenosis was 22.9% for the Multi-Link stent, 24.4% for the NIR stent, 34.1% for the GFX stent, and 35.3% for the PS stent. The restenosis rate of 23.8% in stented vessels > 2.5 mm diameter and < 20 mm length was significantly lower than in vessels < 2.5 mm diameter and > 20 mm length (32.7%; p < 0.01). Factors associated with restenosis, analyzed using a stepwise multivariate logistic regression model, included ostial lesions and post-procedural minimum lumen diameter.
Conclusions. Stent implantation in vessels < 3.0 mm diameter using a newly designed coronary stent yielded favorable clinical results, while there was a high prevalence of restenosis, leading to diffused stenotic lesions, in vessels < 2.5 mm diameter.
The beneficial effects of stent placement in coronary arteries have been established by the STRESS trial and the BENESTENT study. Stents are now widely used. However, stentable lesions are restricted to those < 15 mm in length and no less than 3.0 mm in diameter. In recent years, stents for long lesions or small diameter lesions have been developed. However, the effects of stent implantation in smaller vessels (< 3.0 mm diameter) remain unclear. Indeed, the STRESS trial revealed that the rate of restenosis in small vessels was significantly higher than in vessels > 3.0 mm in diameter. On the other hand, new stents with better designs have recently been developed. In this study, we evaluated the effect of new stents with favorable long-term results in small coronary artery lesions.
Purpose. We evaluated the results of stent placement in small coronary arteries.
Subjects. The subjects were divided into 2 groups: the first contained 911 lesions treated with stenting in the coronary arteries (stent group), and the second contained 1,203 background- and patient-matched lesions treated with balloon angioplasty (POBA group). There was no significant difference in the background of patients or lesions between the groups. A "small coronary artery" was defined as a coronary artery with a reference vessel diameter < 3.0 mm.
Results. There was no significant difference in incidence of acute myocardial infarction (AMI), coronary artery bypass grafting, or death between the groups. In the stent group, acute occlusion (0.8%) and subacute thrombosis (2.1%) occurred. The restenosis rate of 29.8% in the stent group was significantly lower than in the POBA group (38.2%; p < 0.01). The restenosis rate of 19.4% in stented vessels > 3.0 mm diameter was significantly lower than in vessels < 3.0 mm diameter (29.8%; p < 0.01). The rate of restenosis was 22.9% for the Multi-Link stent, 24.4% for the NIR stent, 34.1% for the GFX stent, and 35.3% for the PS stent. The restenosis rate of 23.8% in stented vessels > 2.5 mm diameter and < 20 mm length was significantly lower than in vessels < 2.5 mm diameter and > 20 mm length (32.7%; p < 0.01). Factors associated with restenosis, analyzed using a stepwise multivariate logistic regression model, included ostial lesions and post-procedural minimum lumen diameter.
Conclusions. Stent implantation in vessels < 3.0 mm diameter using a newly designed coronary stent yielded favorable clinical results, while there was a high prevalence of restenosis, leading to diffused stenotic lesions, in vessels < 2.5 mm diameter.
The beneficial effects of stent placement in coronary arteries have been established by the STRESS trial and the BENESTENT study. Stents are now widely used. However, stentable lesions are restricted to those < 15 mm in length and no less than 3.0 mm in diameter. In recent years, stents for long lesions or small diameter lesions have been developed. However, the effects of stent implantation in smaller vessels (< 3.0 mm diameter) remain unclear. Indeed, the STRESS trial revealed that the rate of restenosis in small vessels was significantly higher than in vessels > 3.0 mm in diameter. On the other hand, new stents with better designs have recently been developed. In this study, we evaluated the effect of new stents with favorable long-term results in small coronary artery lesions.
