Clinical outcomes of post-stent intravascular ultrasound examination for chronic total occlusion intervention with drug-eluting stents

Background: Few studies have evaluated intravascular ultrasound (IVUS) use in chronic total occlusion (CTO) percutaneous coronary intervention (PCI). Aims: In CTO-PCI, we aimed to (1) evaluate the clinical benefits of performing post-stent IVUS in preventing adverse clinical events, and (2) identify IVUS parameters and cut-off values for prediction of target lesion revascularisation (TLR)/reocclusion. Methods: A total of 1, 077 patients with 1, 077 CTO lesions treated with drug-eluting stents (DES) were included. Clinical outcomes during a median follow-up of 6.3 years were compared between subjects with and those without post-stent IVUS using the inverse probability weighting method. Results: Of 1, 077 patients, post-stent IVUS was performed in 838 (77.8%) cases while in the remaining 239 (22.2%) cases it was not. In the weighted population, the risk of TLR/reocclusion was significantly lower in subjects with post-stent IVUS (9.6% vs 18.9%, hazard ratio [HR] 0.54, 95% confidence interval [CI]: 0.34-0.86, p=0.01), compared with those without post-stent IVUS. Cox regression analysis showed that minimal stent area (MSA) measured by IVUS was the only parameter independently associated with TLR/reocclusion (HR 0.78, 95% CI: 0.64-0.95; p=0.01) and the optimal MSA cut-off value was 4.9 mm2 for prediction of TLR/reocclusion (area under the curve=0.632, p=0.001). Conclusions: In CTO-PCI with DES, post-stent IVUS evaluation was associated with a lower risk of TLR/reocclusion. The final MSA was independently associated with TLR/reocclusion with a cut-off value of 4.9 mm2.