Intravascular lithotripsy in the management of underexpanded stents

Abstract Introduction Stent underexpansion significantly heightens the risk of major adverse cardiac events (MACE), and available treatment options for this condition remain limited. Intravascular Lithotripsy (IVL) technology disrupts superficial and deep calcium by using localized pulsative sonic pressure waves, emerges as a promising tool for underexpanded stents. Methods Following PRISMA guidelines, we systematically explored PubMed, SCOPUS, and Cochrane databases up to September 3, 2023, for studies evaluating IVL's safety and efficacy in treating underexpanded stents. We gathered angiographic (QCA) and intracoronary imaging (OCT or IVUS) data, examining the stent's minimal diameter stenosis (MDS), minimal lumen diameter (MLD), minimal stent area (MSA), and minimal lumen area (MLA) pre- and post-IVL application. Procedural success constituted the efficacy endpoint, while peri-procedural complications, in-hospital-30-days and long-term mortality, and MACE were safety endpoints Results This meta-analysis comprised 21 studies including 669 patients and 673 treated lesions in underexpanded stent. The mean age was 73.2 ± 2.1 years, with an overall IVL procedural success rate of 93% [(95% Confidence Interval (CI): 88%-96%, I2=29%), while the in-hospital-30-days and long-term mortality incidence were 1% (95% CI: 1%-3%, I2=0%) and 3% (95% CI: 2%-6%, I2=0), respectively. The 30-days target lesion revascularization (TLR) was approximately 6% (95% CI: 3%-12%, I2=50%). There was a significant increase in the MDS [Standardized Mean Difference (SMD): +50.52%, 95% CI: 39.4-61.6, I2=94%)] and in MSA (SMD: +3.52, 95% CI: 2.47 to -4.58, I2=83%) immediately after IVL application. It was observed a significant increase in MLD (SMD: +1.54, 95% CI: 1.09 to 1.98, I2=95%) and in the MLA (SMD: +3.64, 95% CI: 2.62-4.66, I2=5%). Major procedural and device related complications were 3% (95% CI: 1%-6%, I2=0%) and 1% (95% CI: 0%-2%, I2=85%) respectively. Notably low rates were observed for stent thrombosis (0%, 95% CI: 0%-2%, I2=0%), dissections (1%, 95% CI: 1%-4%, I2=0%), perforations (1%, 95% CI: 1%-3%, I2=0%) and no-reflow (0%, 95% CI: 0%-1%, I2=0%). Conclusions IVL demonstrates promise as a safe and effective strategy for underexpanded stent treatment, characterized by low rates of periprocedural complications. Future prospective studies are now warranted to compare IVL to other lesion preparation strategies.30day All-Cause Mortality after IVL use.Minimum Stent Diameter after IVL use.