An Updated Meta-Analysis of Clinical Trials and Observational Studies of Intravascular Ultrasound- versus Angiography-guided Left Main Stenting

Objectives: This updated meta-analysis aimed to consolidate clinical evidence comparing the clinical outcomes of intravascular ultrasound (IVUS)-guided LMCA stenting versus conventional angiography-guided LMCA stenting. Methodology: We included “randomized controlled trials” and “observational studies” published in peer-reviewed English language journals that compared the clinical outcomes of LMCA revascularization using “drug-eluting stents (DES)” via “IVUS-guided” versus “angiography-guided” stenting. The primary outcome of interest was “major adverse cardiovascular events (MACE)”, while secondary outcome variables included “all-cause mortality”, “myocardial infarction (MI)”, “target vessel/lesion revascularization (TVR/TLR)”, and “stent thrombosis (ST)”. Risk ratios (RRs) for each outcome variable were calculated using the “Mantel-Haenszel method”. Results: The analysis included nine studies involving a total of 5,344 patients, with 2,282 undergoing “IVUS-guided” LMCA stenting and 3,062 undergoing “angiography-guided” LMCA stenting. “IVUS-guided” LMCA stenting showed a significant reduction in the risk of MACE compared to “angiography-guided” LMCA stenting, with a RR of 0.46 [95% CI: 0.27 - 0.79]. However, a high level of heterogeneity (I2=94%; p<0.01) was observed among the included studies. Additionally, “IVUS-guided” LMCA stenting was associated with significant reductions in all-cause mortality, MI, and ST, with RRs of 0.38 [0.21 - 0.66], 0.45 [0.26 - 0.77], and 0.24 [0.10 - 0.57], respectively. There was no statistically significant difference in TVR/TLR between “IVUS-guided” and “angiography-guided” LMCA stenting, with an RR of 0.64 [0.27 - 1.51]. Conclusion: “IVUS-guided” LMCA revascularization using DES was associated with a lower risk of MACE, death, MI, and ST compared to conventional “angiography-guided” LMCA stenting.