1. Purpose of Study
    The purpose of this study was to evaluate the efficacy and safety of intracoronary stent implantation for the treatment of diffuse long-term lesions, based on angiographic findings, with stent insertion centered on the most severe stenosis, We aimed to compare the clinical results up to 1 year among patients undergoing extensive stenting without residual lesions by performing a total stenting in the area.





2. Research Background
  Stent length was known to be a cause of strong stent restenosis in the past, but the effect of stent length on stent restenosis after the emergence of drug-eluting stent was greatly reduced. , It is recommended that large stents be inserted where there is no atherosclerosis as much as possible in fear of stent length during drug-releasing stent implantation. An intravenous ultrasound intervention should be considered as an ideal stent insertion site of less than 40% plaque burden Is recommended.
However, it has been reported that a long stent implantation of 31.5 mm or longer may increase the risk of stent thrombosis in a diffuse long lesion, which leads to an excessively long stent length. In the case of a diffuse lesion with a stent length of 80 ± 20 mm, a 6-month restenosis rate of more than 19% was reported.In addition, the use of an overstaged stent implantation for long- And 23% of infarcts, suggesting concern about the safety of long stenting in long lesions.
In addition, the results of the second- or third-generation DES recently introduced due to the rapid development of DES are less known. In contrast, stent implantation with a partial bovine stent placement, which would leave a residual lesion on both ends of the stent, is associated with restenosis or intra-segmental restenosis. The larger diameter of the network compared to the distal and proximal portions of the stent, Is known to be a predictor of endosteal stenosis. In addition, stent thrombosis is the most common cause of stent thrombosis.
According to Demosthenes G, 2009, preliminary studies have shown that the use of a first-generation stent for lower-stent restenosis and angina pectoris recurrence is more advantageous than for long-stenting stent implantation, but a clearer result is required. Therefore, in the actual clinical practice, the choice of the two procedures is difficu- larly selected by the practitioner according to the individual clinical situation in the diffuse long lesion.

3. Research hypothesis
   In a similar study of the study, Am J Cardiol 2009; 104: 786-790 by DEMOSTHENES G. KATRITSIS reported that the spot stenting group compared to the entire stenting group There is no significant difference in 1-year target vessel failure rate. The overall hypothesis was that when the 1-year target vessel failure rate was 7% in the control group, the entire stenting group, the allergic hypothesis was "one-year target vessel failure rate in the spot stenting group, The difference in the 1-year target vessel failure rate of stenting will be within 6% of the non-inferiority margin. "

Treatment

In angio-guided angio-guided stent implantation with diffuse long lesion, stent placement with the stenosis centered on the most severe stenosis was performed and spot stenting was performed, leaving a residual lesion in the proximal or distal portion of the stent. And to compare the clinical results between the patients who underwent extensive stenting and the patients who underwent total stenting without residual lesion.

Arm Label

Target Number of Participant

Arm Type

Arm Description

Stent insertion with angio-guided angiography in the diffuse long lesion with stent insertion centered on the most severe stenosis in the proximal or distal portion of the stent

Arm Label

Target Number of Participant

Arm Type

Arm Description

In angio-guided angio-guided diffuse long lesions, extensive stenting was performed in the entire area of ​​the lesion centered on the most severe stenosis, resulting in complete stenting without residual lesion.

Gender

Age

Description

1. Age Only patients with stable angina or unstable angina over 19 years
2. Reference diameter ≥ 2.5 mm lesion length ≥ 25 mm
3. De novo lesions with% Diameter stenosis ≥50%
4. Patient with Core lesion for spot stenting
For definitions of core lesions, see Clinical Trial Methods.

1. Ascitic (aspirin), clopidogrel (Clopidogrel) and anti-platelet agents, such as those who are contraindicated
2. Left-sided lesions (left main lesion, internal diameter stenosis (diameter stenosis) ≥50%)
3. A recent hematologic disease or white blood cell count of 3000 / mm3 and / or platelet count of 100,000 / mm3. Who show less
4. Severe epicardial disease with a longevity of less than 1 year
5. Those who plan to perform two stenting operations on branch vessels and branch lesions with basilar lesions
6. Patients who underwent emergency stenting after a diagnosis of myocardial infarction within 24 hours (STEMI, NSTEMI can be enrolled after 24 hours)
7. Who can not comply with the research plan

cardiac death

target vessel failure for 12 months

Target vessel myocardial infarction

target vessel failure for 12 months

STEMI and NSTEMI- Including periprocedural myocardial infarction

target vessel failure for 12 months

Ischemic driven target vessel revascularization

target vessel failure for 12 months

All death

for 12 months

STEMI and NSTEMI-periprocedural MI

for 12 months

Target lesion revascularization (TLR)

for 12 months

target vessel revascularization (Non-TVR),

for 12 months

Stent thrombosis

for 12 months