Application Of Ivus In Optimal Diagnosis And Treatment Of CTO-PCI

Objective:In today’s society,the prevalence of chronic total occlusion(CTO)of coronary arteries is increasing.Although interventions for coronary artery disease are well established,CTO remains the most technically challenging percutaneous coronary intervention(PCI)treatment due to its high rate of procedural complications.Intravascular ultrasound(IVUS)has good diagnostic advantages compared with coronary angiography(CAG)in determining the extent of vascular lesions and defining the nature of plaques.In this study,we evaluated the application of IVUS in CTO-PCI such as guiding the selection of stent size and balloon dilation pressure,and also observed its prognostic impact on patients’ major adverse cardiovascular events(MACE).Methods:In this study,119 patients with complete data on a single CTO lesion who visited the Chest Pain Center of Huaihe Hospital of Henan University from May 2019 to May 2021 were selected,and all patients successfully opened the CTO lesion vessel and completed drug-eluting stent implantation with post-expansion balloon treatment as needed.Patients were divided according to their intraoperative use of IVUS guidance to complete PCI: CAG group,61(51.3%)cases in total;and IVUS group,58(48.7%)cases in total.All procedures were performed by senior coronary interventionalists of associate senior level or above.The selection of stent size and post-dilatation use was judged mainly by visual inspection of the target vessel diameter and length,and all patients received standardized antiplatelet and lipid-regulating medications before and after surgery.Intraoperative relevant data were collected from both groups,such as the finding of calcified lesions,false lumen,intramural hematoma,tortuous lesions,occlusion length ≥20 mm,total length of implanted stents,total number of implanted stents,maximum postoperative stent diameter,postdilatation balloon usage rate,maximum postdilatation pressure,maximum postdilatation diameter,and postoperative TIMI blood flow,to compare whether there were any statistical differences.Patients in both groups were followed up for 6to 12 months to observe the incidence of MACE events,and the incidence of secondary endpoints such as in-stent restenosis,heart failure,recurrent angina,and new postoperative arrhythmias,and to compare whether there was any statistical significance.Results:Regarding the surgical data,the two groups showed a significant difference in the detection of calcified lesions(63.8% vs 32.8%,P=0.001),identification of false lumen(19.0%vs 4.9%,P=0.017),detection of intramural hematoma(20.7% vs 0,P=0.000),total length of implanted stent(72.69±19.27 vs 57.12±15.85,P=0.000),maximum postoperative stent diameter(median)(3.5(3.0,4.0)mm vs 3.25(3.0,3.5)mm,maximum postdilatation pressure(median)(20(18,22)atm vs 18(18,20)atm,P=0.000)and maximum postdilatation diameter of the balloon(median)(3.5(3.5,4.0)mm vs 3.0(3.0,3.5)mm,P=0.000).In terms of follow-up outcomes,there was no statistically significant reduction in the incidence of the primary endpoint in the IVUS group compared with the CAG group,and there was no statistical difference between the two(P=0.364);whereas in the secondary outcomes observed,there was no significant reduction in the incidence of in-stent restenosis,heart failure,recurrent angina,and new postoperative arrhythmias in the IVUS group compared with the CAG group,but in the overall incidence of the secondary endpoints IVUS group showed a significant decrease in the overall incidence of secondary endpoints,and the difference was statistically significant(P=0.007).Conclusion:1.Compared to CAG guidance alone,IVUS is valuable in detecting calcified lesions,identifying false lumens,detecting procedural complications such as intramural hematomas,assessing vessel size,and guiding the selection of appropriate stent and post-dilatation balloon sizes in CTO-PCI.2.IVUS-guided CTO-PCI treatment is safer and has important implications in terms of improving the long-term prognosis of patients.