Download Drug-Eluting Stents Better than Bare-Metal Stents

Drug-Eluting Stents Better than Bare-Metal Stents for the Treatment of Left
Main Coronary Artery Disease
Background Information:
The left main coronary artery (LMCA) disease is characterized by atherosclerosis in the epicardial
coronary arteries. It is often accompanied by a series of complications such as in-stent restenosis for the
treatment of percutaneous coronary intervention (PCI). It has been associated with poor prognosis
when treated medically, especially during the period of bare-meta stents (BMS).
Bare-meta stents (BMS) is a stent without a coating or covering and is a mesh-like a tube of thin wire.
Drug-eluting stents (DES) is a peripheral or coronary stent placed into narrowed, diseased peripheral or
coronary arteries that slowly release a drug to block cell proliferation. DES and adjunction
pharmacological therapy have led to a re-evaluation of the potential use of PCI for the treatment of
LMCA disease. The development of DES, which is associated with significantly lower rates of restenosis
and repeat revascularization, had made PCI in patients with LMCA disease more feasible.
Objective of the Study:
The primary objective of the study was to compare the efficacy of the drug-eluting stents and baremetal stents for the treatment of left main coronary artery.
Methods and Materials:
Sample Size:
The study included 1159 consecutive patients who underwent PCI for LMCA. In that, 1020 underwent
DES implantation and 139 underwent BMS implantation.
Inclusion Criteria:
The patients who had clinical symptoms and signs of myocardial ischemia and angiographically
documented for (ULMCA) unprotected long main coronary arteries lesions were included in the study.
Exclusion Criteria:
Patients with cardiogenic shock, contraindications to aspirin or clopidogrel therapy, or planned
upcoming noncardiac surgery were excluded from the study.
Procedure:
A glycoprotein IIb/IIIa inhibitor was administered as needed during the PCI procedure based on the
angiographic findings and operator judgment. Predilatation was routinely performed. The location and
the length of the stent were selected. The side branch stent was placed with small protrusion into the
main vessel, or a balloon in the main vessel and was simultaneously dilated when the side branch stent
was deployed. After the stent implantation, routinely high-pressure dilatation was performed. It also
includes final kissing balloon dilatation after distal LMCA bifurcation stenting. Aspirin and clopidogrel
were administered before the surgery and continued. Clopidogrel (75 mg/d) was continued as a
maintenance dose for 3-6 months after BMS transplantation and 12-24 months after DES implantation.
Aspirin (300 mg/d) was continued for one month. The clinical outcome of the study was obtained after 5
years.
Statistical Analysis:
The continuous variables were expressed as the mean ± standard deviation and compared between
groups using the t-test. The categorical data was expressed as percentages and compared between
groups using the Chi-square or Fisher’s exact tests. The cumulative incidence of the events was
calculated using the Kaplan –Meier method and the estimated curves were compared using log-rank
test.
Results:
Parameters
MACE (Major adverse cardiac
event)
MI (Myocardial Infarction)
TIR (Target-lesion revascularization)
CV (Cardiovascular) death
Stent thrombosis
BMS(Bare-metal stents)
41
16
23
19
5
DES(Drug-eluting stents)
25
7
14
4
6
The MACE, MI, TIR, CV death was significantly low in the DES group than in the BMS group, but there
was a significant increase in the stent thrombosis.
Discussion:
Percutaneous coronary intervention was increasingly performed for the treatment of lesions. DES
implantation was used with increased frequency because it is associated with lower rates of restenosis
than BMS implantation when used for the treatment of standard coronary lesions.
Conclusion:
The overall outcome of the study showed that DES implantation is safe and effective in the long-term for
the treatment LMCA stenosis compared with BMS implantation.
Reference:
Wang XZ, et al. Comparison of the Efficacy of Drug‑eluting Stents versus Bare‑metal Stents for the
Treatment of Left Main Coronary Artery Disease. Chin Med J (Engl). 2015 Mar 20; 128(6):721-6.
Available at: http://www.ncbi.nlm.nih.gov/pubmed/25758262/