Objective: Intravascular ultrasound (IVUS) has developed as a preferable choice for optimizing the stenting procedures mainly because it will have good access to vessel size, lesion length, or severity accurately. However, it still remains unclear about the benefits of IVUS guidance in drug-eluting stent (DES) implantation for patients with unprotected left main coronary artery (ULMCA) stenosis. The aim of the present study was to evaluate the clinical outcomes with respect to IVUS-guided DES implantation for these patients.
Methods: A total of 336 consecutive patients from December 2010 to December 2015 were enrolled in the study. The patients were then randomly assigned into two groups: IVUS-guided group (n=167) and control group (n=169). The primary endpoint was the incidence of composite major adverse cardiac events (MACEs), including cardiac death, myocardial infarction (MI), and target vessel revascularization (TVR). The risk of stent thrombosis (ST) was chosen as the safety endpoint.
Results: After a 1-year follow-up, the occurrence of composite MACE in the IVUS-guided group was significantly lower than that in the control group (13.2% vs. 21.9%, p=0.031), which might mainly result from the significant reduction in the risk of cardiac death (1.8% vs. 5.9%, p=0.048). Dramatically, the risk of MI did not differ significantly between the two groups (11.4% vs. 13.6%, p=0.478), though a tended reduction in TVR was observed under IVUS guidance (4.2% vs. 8.9%, p=0.068). There was no statistical significance between the two groups with respect to the risk of target lesion revascularization (IVUS-guided vs. control: 1.2% vs. 3.0%, p=0.239) and ST (IVUS-guided vs. control: 1.2% vs. 3.0%, p=0.246).
Conclusion: The possible feasibility of IVUS-guided DES implantation for patients with ULMCA stenosis was supported by the present study. Larger and more powerful randomized trials were still warranted to research the whole benefits of IVUS guidance for these patients.