Major adverse cardiac outcomes of provisional percutaneous coronary intervention technique for bifurcation lesions and percutaneous coronary intervention procedures for lesions close to the bifurcation region at 1-year follow-up

Introduction and objective: Despite the advances in technology, patients undergoing percutaneous coronary intervention still experience complications during or after the procedure. Among the reasons are the location of the lesion, the vessel where the lesion is located and the way the stent is implanted. In this study, we will investigate major adverse cardiac events at 1-year follow-up in patients with lesions close to bifurcation region with the extension of the stent to the carina during stent implantation. Materials and methods: After approval from the ethics committee of Yüzüncü Yıl University Dursun Odabaş Medical Center, 179 patients with bifurcation zone (BB) lesions and 177 patients with near bifurcation zone (NBZ) lesions were included in the study. BB lesions includes lesions ≤4 mm away from the bifurcation point, while BBY lesions includes lesions <3 mm away from this area. Demographic and clinical data of all the patients were recorded. Angiographic images were analyzed quantitatively (QCA). All patients, except for the dead patients, were contacted at the first year and were followed up in the outpatient clinic. Results: 69% of the patients whose the mean age was 61.5 years and were men. Age, gender, clinical and blood tests were statistically similar in the two groups (>p=0.05). The bifurcation angle and proximal reference vessel diameter were larger in patients with NBZ lesions (p=0.036). There was a significant difference between the two groups in terms of stent length, number of stents and number of lesions (p=0.05). Most of the procedures were performed in the LAD-Dg in the BB group, whereas most of the procedures were performed in the LAD osteal in the NBZ group. The incidence of major adverse cardiac events (MACE) at 1-year follow-up between the two groups was higher in the NBZ group, but not statistically significant (BB: 3.4%, BBY: 5.1%, p=0.416). The incidence of angina was not statistically significant between the two groups but was more common in the BB group (BB: 20%, BBY: 16%, p=0.298). When divided into two groups according to the type of procedure as provisional stenting (PS) and osteal stenting (OS), MACE was more common in the OS group, but not statistically significant (PS: 3.3%, OS: 5.4%, p=0.333). There were similar results in terms of angina incidence (PS: 21%, OS 14%, p=0.083). Kaplan-meier survival graph also showed no difference between the groups. Discussion and conclusion: When implanting a stent in NBZ lesions, the proximal edge of the stent is implanted in the clear area of the proximal of the lesion. This area may coincide with the carina region. Therefore, even if the lesion is not in the bifurcation, plaque rupture, corner dissection, carina and plaque displacement may occur due to the extension of the stent to the carina. This may lead to MACE in the long term. The hypothesis of the study was formed on this basis. Accordingly, we found that procedures performed on patients with BB lesions cause at least as many major adverse cardiac events (MACE) as provisional stenting (PS) of BB lesions at 1-year follow-up. Although MACE was similar between the groups at follow-up, it was higher in the BB lesion group. In particular, the rate of angina was higher in the PS group than in the OS group. This may be due to the fact that the proximal vessel was stented throughout while the side branch remained under the stent. In addition, even though angina was less common in the OS group, the rate of the evidence of ischemia and revascularization was higher than in the PS group. This means that we should be more alert in the presence of evidence of ischemia in patients undergoing OS.