Long-term impact of intravascular ultrasound-guidance for percutaneous coronary intervention on unprotected left main. The IMPACTUS-LM, an observational, multicentric study

Introduction The potential benefit on long term outcomes of Percutaneous Coronary Intervention (PCI) on Unprotected Left Main (ULM) driven by IntraVascular UltraSound (IVUS) remains to be defined. Methods IMPACTUS LM-PCI is an observational, multicenter study that enrolled consecutive patients with ULM disease undergoing coronary angioplasty in 13 European high-volume centers from January 2002 to December 2015. Major Adverse Cardiovascular Events (MACEs) a composite of cardiovascular (CV) death, target vessel revascularization (TVR) and myocardial infarction (MI) were the primary endpoints, while its single components along with all cause death the secondary ones. Results 627 patients with ULM disease were enrolled, 213 patients (34%) underwent IVUS-guided PCI while 414 (66%) angioguided PCI. Patients in the two cohorts had similar prevalence of risk factors except for active smoking and clinical presentation. During a median follow-up of 7.5 years, 47 (22%) patients in the IVUS group and 211 (51%) in the angio-guided group underwent the primary endpoint (HR 0.42; 95% CI [0.31–0.58] p < 0.001). After multivariate adjustment, IVUS was significantly associated with a reduced incidence of the primary endpoint (adj HR 0.39; 95% CI [0.23–0.64], p < 0.001), mainly driven by a reduction of TVR (ad HR 0.30, 95% CI [0.15–0.62], p = 0.001) and of all-cause death (adj HR 0.47, 95% CI [0.28–0.82], p = 0.008). IVUS use, age, diabetes, side branch stenosis, DES and creatinine at admission were independent predictors of MACE. Conclusions In patients undergoing ULM PCI, the use of IVUS was associated with a reduced risk at long-term follow-up of MACE, all-cause death and subsequent revascularization.