Prognostic Value of Logistic Clinical Syntax Score in Coronary Bifurcation Lesions Treated with Double Stent Technique

Gökhan Demirci, Serkan Aslan, Ali Rıza Demir, Begüm Uygur, Ayan Işık, Enes Arslan, Mehmet Ertürk

Clinic of Cardiology, Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Research and Training Hospital, İstanbul, Türkiye

Keywords: Atherosclerosis; percutaneous coronary intervention

Abstract

Introduction: In this study, we aimed to investigate the relationship between the preprocedural logistic clinical SYNTAX score (Log CSS) and major cardiovascular events (MACE) in patients with true bifurcation lesions who underwent revascularization with the double stent strategy.

Patients and Methods: A total of 233 non-ST elevation myocardial infarction (NSTEMI) patients who underwent revascularization with a double stent strategy were retrospectively included in the study. Anatomical SYNTAX score (SS) and log CSS were calculated. The patients were divided into two groups according to the cut-off value determined by ROC analysis. The prediction of two-year MACE with Log CSS was evaluated.

Results: MACE developed in 33.9% of patients with high Log CSS and 8.5% of patients with low Log CSS (p< 0.001). In the Kaplan-Meier survival analysis, the long-term survival of the high Log CSS patients was significantly lower than the low Log CSS group (Log-rank p< 0.001). In multivariate COX analyses, high Log CCS (HR= 3.781; 95% CI= 1.706-8.377; p= 0.001) was the strongest independent predictor of MACE.

Conclusion: Log CSS can be a simple and useful tool to predict the development of MACE in patients with true bifurcation lesions revascularized by percutaneous coronary intervention.

Introduction

Acute coronary syndrome patients undergoing percutaneous coronary intervention (PCI) procedures are at high risk for in-hospital and long-term adverse cardiovascular events (MACE) despite advances in stent technology and new techniques(1). Coronary bifurcation lesions are one of the most difficult procedures in interventional cardiology. Coronary bifurcation lesions constitute approximately 15-20% of patients undergoing PCI. The complication rate of bifurcation lesions is high; however, the procedural success is low. They are complex lesions with higher rates of stent thrombosis and restenosis in follow-ups(2-4). Therefore, various scoring techniques have been developed to predict mortality and morbidity in patients after PCI. The SYNTAX score (SS) is a scoring system that is used to determine the most appropriate revascularization strategy between PCI and coronary artery bypass grafting (CABG), based on the complexity and severity of coronary lesions(5,6). It has been recommended in both European and American revascularization guidelines(7,8). It has been found to predict accurately the risk of adverse events in the long-term outcome of patients undergoing PCI(9). However, SS is only an anatomy-based tool for quantitatively assessing and grading the angiographic features of coronary lesions, which significantly limits the accuracy of long-term mortality or major adverse cardiac events(10). To overcome this limitation and improve risk stratification, the Logistics Clinical SYNTAX Score (Log CSS), a combined risk scoring system including clinical (age, creatinine clearance, left ventricular ejection fraction (LVEF)) and angiographic parameters (SS), has been developed(11).

Our aim was to evaluate the relationship between Log CSS and MACE in patients with true bifurcation lesions who underwent double stent revascularization, and to compare Log CSS and SS in terms of MACE prediction in this patient group.

Materials and Methods

Study Population and Methods

Our study retrospectively included 233 non-ST elevation myocardial infarction (NSTEMI) patients who underwent revascularization with a double stent strategy in our hospital between May 2011 and October 2019.

Inclusion criteria were main vessel reference diameter ≥2.5 mm, lateral vessel reference diameter ≥2.25 mm, 1.1.1 or 0.11 or 1.0.1 lesions according to Medina classification, and revascularization with two stent strategies. Cardiogenic shock, cardiopulmonary resuscitation, severe left ventricular systolic dysfunction (LVEF< 30%), intolerance to antiplatelet therapy, discontinuation of antiplatelet therapy for any reason, presence of intraluminal thrombus, severe calcification and severe tortuosity were the exclusion criteria.

The study was approved by the ethics committee of our institution and was performed in accordance with the requirements of the Declaration of Helsinki. (Date: 08/05/2019, Decision No: A-02).

SYNTAX and Logistic Clinical SYNTAX Score

Two interventional cardiologists, blinded to the study protocol and patient characteristics, evaluated the angiographic images of all patients. The SYNTAX (synergy between TAXUS and PCI and cardiac examination) score was calculated using the SYNTAX website. The SS for each patient was calculated by using the SS algorithm for all coronary lesions with more than 50% stenosis in vessels greater than 1.5 mm in diameter; the culprit lesion was calculated retrospectively by considering angiographic images of the infarct-related artery before any intervention. The SS was combined with a simple clinical risk score including age, ejection fraction, and creatinine clearance to generate log CSS. The Log CSS core model used in this study was calculated according to the formula developed by Farooq et al(11). Log CSS calculation criteria are summarized in Figure 1. The intra- and inter-observer variability for all measurements is less than 5%.

Figure 1. Log CSS calculation criteria. CrCl: Creatinin clearence, LV: Left ventricle.

Clinical Characteristics and Follow-up

The baseline demographic, clinical, and laboratory parameters of the patients were recorded retrospectively, and all-cause mortality, cardiac mortality, stroke, myocardial infarction (MI), target vessel revascularization (TVR), target lesion revascularization (TLR) were scanned in patients who were followed up for a median of 24.0 (14.8-32.0) months after PCI. The combination of these endpoints was considered as MACE.

Telephone and mobile phone calls, electronic data, and outpatient clinics were used to follow up on the patients. The time from the index procedure date to the end of the follow-up date or the development of any MACE is referred to as clinical follow-up.

Statistical Analysis

Statistical analysis of the study was performed with the SPSS Version 24.0 software (SPSS Inc., Chicago, Illinois, USA). Whether the variables show a normal distribution was evaluated by using visual (histograms, probability curves) and analytical methods (Kolmogorov-Smirnov’s and Shapiro-Wilk). Normally distributed numerical variables were expressed as mean ± standard deviation (SD), non-normally distributed numerical variables were expressed as median (interquartile range), and categorical variables were expressed as percent (%). ROC (Receiver Operating Characteristic) curve and Youden index [max (Sensitivity + Selectivity - 1)] were used to determine the log CSS predictive value that best detects the presence of MACE, and an area under the ROC curve that was greater than 0.5 was considered significant.

Statistical analysis of numerical variables between groups was performed with Student’s t-test or Mann-Whitney U test, and analysis of categorical variables was performed with Chisquare or Fisher’s exact test. A univariable and multivariable Cox proportional hazards model was used to calculate hazard ratios (HRs) and 95% confidence intervals (95% CI) for MACE. Event-free survival curves were constructed using the Kaplan-Meier method and compared using the log-rank test. Throughout the present study, a p-value of

Results

The study included 233 patients (mean age= 59.5 ± 11.1 years) and 77.7% (181/233) of the study population was male. The patients were divided into two groups according to the cut-off value determined by the ROC curve and the Youden index. Patients with a log CSS value of >6 were included in the high log CSS group (n= 56) and those with a log CSS value of ≤6 in the low log CSS group (n= 177). As expected, patients in the high log CSS group had significantly higher age and SS, and lower GFR and LVEF. Moreover, the high log CSS group had a lower percentage of male patients (67.9% vs. 80.8%, p= 0.043) and higher rates of DM (58.9% vs. 32.2%, p< 0.001) and HT (62.5% vs. 42%, p= 0.008) (Table 1).

Table 1. Comparison of characteristics of study patients with Log CSS

Table 1. Comparison of characteristics of study patients with Log CSS (continued)

The comparison of the two groups in terms of the endpoints constituting MACE after a two-year follow-up was shown in Figure 2. Although MI, stroke, TLR, and TVR were detected more in the high log CSS group, they could not reach statistical significance. CV mortality and all-cause mortality rates were significantly higher in the high log CSS group. As a result, patients in the high log CSS group (33.9%) experienced a higher rate of MACE than patients in the low log CSS group (8.5%) (p< 0.001).

Figure 2. Comparison of two-year clinical outcomes of high and low log CSS groups. MI: Miyocardial infarction, TLR: Target lesion revascularization, TVR: Target vessel revascularization, CV: Cardiovascular, MACE: Major adversc cardiovascular event.

Initially, univariable COX regression analysis was performed to identify effective predictors of MACE development over time in patients revascularized with the double stent strategy. Significant (p< 0.1) parameters in this analysis - PCI history, cerebrovascular disease history, triglyceride level, bifurcation location, POT, final kissing, contrast media volume, and log CSS- were subjected to multivariable analysis. As a result of the multivariable analysis, high log CCS (HR= 3.781, 95% CI= 1.706-8.377, p= 0.001) and final kissing (HR= 0.241, 95% CI= 0.059-0.991, p= 0.049) were determined as independent predictors of MACE (Table 2). As shown in Table 3, patients were categorized based on different stenting techniques used for bifurcation lesion revascularization, to determine MACE predictors. A history of cerebrovascular disease and no final kissing were found to be associated with MACE in the TAP technique, high log CSS and no final kissing were associated with MACE in the culotte technique, and high log CSS, previous PCI, and the volume of contrast media were associated with MACE in the crush technique.

Table 2. Univariable and multivariable logistic regression analyzes for the development of MACE

Table 3. Multivariable logistic regression analysis for the development of MACE in different stenting strategies

In Figure 3, Kaplan-Meier cumulative survival curves for MACE were observed in patients categorized according to log CCS. Kaplan-Meier curves showed that the high log CSS group had a higher incidence of MACE compared to the low log CSS group (Log-rang test, p< 0.001).

Figure 3. Kaplan-Meier curves for survival at two-year follow-up after index procedure according to whether log CCS is high or low.

ROC curves were drawn for both scores to compare log CSS and SS in terms of power to detect MACE development (Figure 4). The AUC value obtained with log CSS was higher than that obtained with SS (0.710 vs 0.610). A log CSS value greater than 6 could detect MACE development with a sensitivity of 55.9% and a specificity of 81.4%.

Figure 4. Long-term risk prediction with ROC curve of Log CCS and SS. CSS: Clinical SYNTAX score, AUC: Area under the curve, CI: Confidence interval.

Discussion

The main findings of our study are the following: 1) 14.4% of the entire patient group developed MACE, 2) MACE development was statistically higher in the high log CSS group than the low log CSS group, 3) long-term survival of high log CSS patients was significantly lower than the low-log CSS group, 4) high log CCS was the strongest independent predictor of MACE, 5) log CSS is superior to anatomical SS in predicting two-year MACE development.

Patient selection plays an important role in treatment decisions, and the identification of potential risks is an important part of the decision-making process. Risk classification score models are regarded as effective methods of predicting adverse events following procedures and useful tools for assisting patients and physicians in selecting the best treatment strategy(12,13).

The SYNTAX score is an angiography-based tool created during the design of the SYNTAX trial to quantify the extent and complexity of coronary artery disease and to determine the most appropriate revascularization strategy between PCI and CABG(5,6). This score has been shown to predict PCI outcomes(14-16) and has been included in European and American revascularization guidelines to assist in the appropriate selection of revascularization strategy(17,18).

However, SS is only an anatomy-based tool for quantitatively assessing and grading the angiographic features of coronary lesions, which significantly limits the accuracy of long-term mortality or major adverse cardiac events. There may be several reasons for this limitation. First of all, this can be explained by the association of anatomical complexity (calcification, tortuosity, lesion length, etc.) evaluated in SS with in-hospital or early-stage adverse cardiac events (target vessel revascularization, stent thrombosis, myocardial infarction). Secondly, sometimes patients with equivalent anatomic SS can have very different outcomes after revascularization, depending on the presence of comorbidities. Therefore, it may not be sufficient to predict two-year mortality or MACE. To overcome this limitation, new scores including clinical and angiographic variables have been developed to predict mortality and adverse outcomes with higher accuracy when compared to risk scores based on anatomy alone in patients undergoing PCI or CABG. Comorbidities derived from surgical scores such as ACEF(19,20) or EuroSCORE24(21) were included in anatomical SS. Following this, log CSS was developed by combining anatomical SS with clinical factors selected according to logistic regression coefficients(11,22,23). First introduced by Farooq et al., log CSS(11) consists of both clinical (age, creatinine, LVEF) and anatomical (SS) parameters. It has been reported that log CSS is more accurate than SS in estimating one-year and threeyear cardiovascular mortality after PCI(11,22). Kawashima et al. found log CSS to be a significant predictor of two-year mortality after PCI in STEMI patients(24). Consistent with the literature, our study showed that log CSS, which reflects the logistic evolution of SYNTAX-derived scores, has a superior ability to predict two-year MACE development compared to anatomical SS. In addition, Uygur et al. found that log CSS was an independent predictor of in-hospital mortality in patients with ST-elevation myocardial infarction who underwent emergency coronary artery bypass graft surgery(25). Öztürk et al. used log CSS to predict Saphenous Vein Graft failure in patients undergoing coronary artery bypass grafting(26).

Coronary bifurcation lesions account for 15% to 20% of all percutaneous coronary interventions and are among the most challenging lesions in interventional cardiology in terms of both procedural success and long-term clinical outcomes (27). Treatment of bifurcation coronary lesions remains a challenging area where best practice has not yet been fully established. Short-term complications such as periprocedural myocardial infarction and long-term complications such as in-stent restenosis and stent thrombosis are higher in patients with bifurcation lesions(28). The use of drug-eluting stents in percutaneous coronary intervention has improved the short- and long-term outcomes of bifurcation lesion treatment(29). While current guidelines recommend the provisional technique as the preferred approach, the double stent strategy remains a viable option for patients with complex true bifurcation lesions. However, the optimal double-stent strategy for the treatment of this complex subset of lesions remains a matter of technical debate, and there is limited information on longterm clinical outcomes(30). There is no clear evidence that a specific double stenting technique is superior to others in improving clinical outcomes after coronary bifurcation intervention(31). The presence of diabetes, the final kissing balloon, the use of noncompliant balloons, and pre-dilatation were all predictive of rerevascularization(31). There are few studies evaluating the prognostic value of SS in bifurcation patients. Pillai et al. investigated the effect of SS 1 and SS 2 scores on MACE following stenting in 103 patients with unprotected left main bifurcation disease. As a result of the study, they showed that both scorings were effective on target lesion revascularization and mortality. In this sense, SS 1 was found to be superior to SS 2(32). In our study, SS was also a predictor of MACE in patients with bifurcation lesions treated with a double stent strategy, but Log CSS performed better than SS. Furthermore, in the subgroup analysis performed according to stenting techniques, it was an independent predictor of MACE in log CSS, Crush, and Culotte techniques, but not in the TAP technique. We think that this result is due to the fact that the TAP technique is less complex, and the procedure duration is shorter than the other two methods(33). Based on this finding, we believe that in patients with high Log CSS, it would be more appropriate to intervene in a bifurcation lesion with the TAP technique as a double stent strategy.

To the best of our knowledge, no data have been published regarding the possible relationship between log CSS and MACE in coronary bifurcation lesions undergoing PCI with a double stent strategy. Therefore, our study is the first to evaluate the predictive value of log CSS in patients who underwent a double stent strategy for coronary bifurcation lesions.

Limitations

This study was designed as a retrospective and single-center study. Large randomized clinical studies are needed. The choice of treatment strategy, stent type, and stenting technique was at the discretion of the operator. The stents used in our study were first-generation; the exclusive use of first-generation DES may have affected clinical outcomes.

Conclusion

Our study reveals that log CSS, a new version of anatomical SS enhanced with clinical parameters, has a predictive value for clinical endpoints (all-cause mortality, re-revascularization, and hospitalization) in patients with coronary bifurcation lesions treated with the double-stent strategy. Log CSS appears to have better predictive value in estimating two-year MACE compared to SS and allows for a personalized risk assessment of patients undergoing PCI. It should be used for long-term risk stratification of patients undergoing PCI. Large prospective studies are required to further evaluate our findings.

Cite this article as: Demirci G, Aslan S, Demir AR, Uygur B, Işık A, Arslan E, et al. Prognostic value of logistic clinical syntax score in coronary bifurcation lesions treated with double stent technique. Koşuyolu Heart J 2022;25(3):240-249.

Ethics Committee Approval

The study was approved by the Ethics Committee of İstanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Training and Research Hospital and was performed in accordance with the requirements of the Declaration of Helsinki. (Date: 08/05/2019, De-cision No: A-02).

Peer Review

Externally peer-reviewed.

Author Contributions

Concept/Design - SA, ME, GD; Analysis/Inter- pretation - AD, GD; Data Collection - EA, AI, GD; Writing - BU, GD; Critical Revision - BU, EA, GD; Final Approval - ME, GD; Statistical Analysis - AD, GD; Overall Responsibility - GD.

Conflict of Interest

The authors have no conflicts of interest to declare.

Financial Disclosure

The authors declare that this study has received no financial support.

References

  1. Steg PG, James SK, Atar D, Badano LP, Blöstrom-Lundqvist C, Borger MA, et al. ESC guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation. Eur Heart J 2012;33(20):2569-619. [Crossref]
  2. Louvard Y, Lefèvre T, Morice MC. Percutaneous coronary intervention for bifurcation coronary disease. Heart 2004;90(6):713-22. [Crossref]
  3. Bennett J, Dubois C. Coronary bifurcation lesions: Is less more. J Thorac Dis 2016;8(10):1351-4. [Crossref]
  4. Meier B, Gruentzig AR, King SB, Douglas Jr JS, Hollman J, Ischinger T, et al. Risk of side branch occlusion during coronary angioplasty. Am J Cardiol 1984;53(1):10-4. [Crossref]
  5. Serruys PW, Morice MC, Kappetein AP, Colombo A, Holmes DR, Mack MJ, et al. Percutaneous coronary intervention versus coronaryartery bypass grafting for severe coronary artery disease. N Engl J Med 2009;360(10):961-72. [Crossref]
  6. Sianos G, Morel MA, Kappetein AP, Morice MC, Colombo A, Dawkins K, et al. The SYNTAX Score: An angiographic tool grading the complexity of coronary artery disease. EuroIntervention 2005;1(2):219-27.
  7. Kolh P, Windecker S, Alfonso F, Collet JP, Cremer J, Falk V, et al. 2014 ESC/EACTS guidelines on myocardial revascularization: The task force on myocardial revascularization of the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS). Developed with the special contribution of the European Association of Percutaneous Cardiovascular Interventions (EAPCI). Eur J Cardiothorac Surg 2014;46(4):517-92.
  8. Patel MR, Dehmer GJ, Hirshfeld JW, Smith PK, Spertus JA, Masoudi FA, et al. ACCF/SCAI/STS/AATS/AHA/ASNC/HFSA/SCCT 2012 appropriate use criteria for coronary revascularization focused update: A report of the American College of Cardiology Foundation Appropriate Use Criteria Task Force, Society for Cardiovascular Angiography and Interventions, Society of Thoracic Surgeons, American Association for Thoracic Surgery, American Heart Association, American Society of Nuclear Cardiology, and the Society of Cardiovascular Computed Tomography. J Thorac Cardiovasc Surg 2012;143(4):780-803. [Crossref]
  9. Sinning JM, Stoffel V, Grube E, et al. Combination of angiographic and clinical characteristics for the prediction of clinical outcomes in patients undergoing unprotected left main coronary artery stenting. Clin Res Cardiol. 2012 Jun;101(6):477-85. [Crossref]
  10. Garg S, Sarno G, Garcia-Garcia HM, Girasis C, Wykrzykowska J, Dawkins KD, et al. A new tool for the risk stratification of patients with complex coronary artery disease: The clinical SYNTAX score. Circ Cardiovasc In- terv 2010;3(4):317-26. [Crossref]
  11. Farooq V, Vergouwe Y, Räber L, Vranckx P, Garcia H, Diletti R, et al. Combined anatomical and clinical factors for the long-term risk stratification of patients undergoing percutaneous coronary intervention: The logistic clinical SYNTAX score. Eur Heart J 2012;33(24):3098-104. [Crossref]
  12. Capodanno D, Giacoppo D, Dipasqua F, Micciche E, Licitra C, Di Salvo ME, et al. Usefulness of the logistic clinical SYNTAX score for predicting 1-year mortality in patients undergoing percutaneous coronary intervention of the left main coronary artery. Catheter Cardiovasc Interv 2013;82(4):446-52. [Crossref]
  13. Farooq V, Vergouwe Y, Généreux P, Bourantas CV, Palmerini T, Caixeta A, et al. Prediction of 1-year mortality in patients with acute coronary syndromes undergoing percutaneous coronary intervention: Validation of the logistic clinical SYNTAX (synergy between percutaneous coronary interventions with taxus and cardiac surgery) score. JACC Cardiovasc In- terv 2013;6(7):737-45. [Crossref]
  14. Stone GW, Sabik JF, Serruys PW, Simonton CA, Genereux P, Puskas J, et al. Everolimus-eluting stents or bypass surgery for left main coronary artery disease. N Engl J Med 2016;375(23):2223-35. [Crossref]
  15. Mohr FW, Morice MC, Kappetein AP, Feldman TE, Stahle E, Colombo A, et al. Coronary artery bypass graft surgery versus percutaneous coronary intervention in patients with three-vessel disease and left main coronary disease: 5-year follow-up of the randomised, clinical SYNTAX trial. Lancet 2013;381(9876):629-38. [Crossref]
  16. Capodanno D, Di Salvo ME, Cincotta G, Miano M, Tamburino C, Tambu- rino C. Usefulness of the SYNTAX score for predicting clinical outcome after percutaneous coronary intervention of unprotected left main coronary artery disease. Circ Cardiovasc Interv 2009;2(4):302-8. [Crossref]
  17. Kim YH, Park DW, Kim WJ, Lee JY, Yun SC, Kang SJ, et al. Validation of SYNTAX (Synergy between PCI with taxus and cardiac surgery) score for prediction of outcomes after unprotected left main coronary revascularization. JACC Cardiovasc Interv 2010;3(6):612-23. [Crossref]
  18. Montalescot G, Sechtem U, Achenbach S, Andreotti F, Arden C, Budaj A, et al. 2013 ESC guidelines on the management of stable coronary artery disease: The Task Force on the management of stable coronary artery disease of the European Society of Cardiology. Eur Heart J 2013;34(38):2949-3003. [Crossref]
  19. Ranucci M, Castelvecchio S, Menicanti L, Frigiola A, Pelissero G. Risk of assessing mortality risk in elective cardiac operations: Age, creatinine, ejection fraction, and the law of parsimony. Circulation 2009;119(24):3053-61. [Crossref]
  20. Chichareon P, Modolo R, van Klaveren D, Takahashi K, Kogame N, Chang CC, et al. Predictive ability of ACEF and ACEF II score in patients undergoing percutaneous coronary intervention in the GLOBAL LEADERS study. Int J Cardiol 2019;286:43-50. [Crossref]
  21. Nashef SA, Roques F, Michel P, Gauducheau E, Lemeshow S, Salamon R. European system for cardiac operative risk evaluation (EuroSCORE). Eur J Cardiothorac Surg 1999;16(1):9-13. [Crossref]
  22. Iqbal J, Vergouwe Y, Bourantas CV, van Klaveren D, Zhang YJ, Campos CM, et al. Predicting 3-year mortality after percutaneous coronary intervention: Updated logistic clinical SYNTAX score based on patientlevel data from 7 contemporary stent trials. JACC Cardiovasc Interv 2014;7(5):464-70. [Crossref]
  23. Chichareon P, Onuma Y, van Klaveren D, Modolo R, Kogame N, Takahashi K, et al. Validation of the updated logistic clinical SYNTAX score for all-cause mortality in the GLOBAL LEADERS trial. EuroIntervention 2019;15(6):539-46. [Crossref]
  24. Kawashima H, Hara H, Wang R, Ono M, Gao C, Takahashi K, et al. Usefulness of updated logistic clinical SYNTAX score based on MI-SYNTAX score in patients with ST-elevation myocardial infarction. Catheter Cardiovasc Interv 2021;97(7):919-28. [Crossref]
  25. Uygur B, Demir AR, Guner A, Iyigun T, Uzun N, Celik O. Utility of logistic clinical SYNTAX score in prediction of in-hospital mortality in STelevation myocardial infarction patients undergoing emergent coronary artery bypass graft surgery. J Card Surg 2021;36(3):857-863. [Crossref]
  26. Ozturk D, Celik O, Cakmak HA, Akın F, Aslan S, Enhos A, et al. Usefulness of the logistic clinical syntax score in prediction of saphenous vein graft failure in patients undergoing coronary artery bypass grafting. Angiology 2015;66(8):714-20. [Crossref]
  27. Latib A, Colombo A. Bifurcation disease: What do we know, what should we do? JACC Cardiovasc Interv 2008;1(3):218-26.
  28. Chen SL, Zhang JJ, Ye F, Tian NL, Sheiban I, Jepson N, et al. Periprocedural myocardial infarction is associated with increased mortality in patients with coronary artery bifurcation lesions after implantation of a drugeluting stent. Catheter Cardiovasc Interv 2015;85(1):696-705. [Crossref]
  29. Colombo A, Chieffo A. Drug-eluting stent update 2007: Part III: Technique and unapproved/unsettled indications (left main, bifurcations, chronic total occlusions, small vessels and long lesions, saphenous vein grafts, acute myocardial infarctions, and multivessel disease). Circulation 2007;116(12):1424-32. [Crossref]
  30. Steigen TK, Maeng M, Wiseth R, Erglis A, Kumsars I, Narbute I, et al. Randomized study on simple versus complex stenting of coronary artery bifurcation lesions: The Nordic bifurcation study. Circulation 2006;114(18):1955- 61. [Crossref]
  31. Song PS, Song YB, Lee JM, Hahn JY, Choi SH, Choi JH, et al. Major predictors of long-term clinical outcomes after percutaneous coronary intervention for coronary bifurcation lesions with 2-stent strategy: Patientlevel analysis of the Korean bifurcation pooled cohorts. JACC Cardiovasc Interv 2016;9(18):1879-86. [Crossref]
  32. Pillai AA, Gousy VS, Kottyath H, Satheesh S, Selvaraj R, Jayaraman B. Long-term outcomes following left main bifurcation stenting in Indian population-analysis based on SYNTAX I and II scores. Indian Heart J 2018;70(3):394-8. [Crossref]
  33. Hildick-Smith D, Behan MW, Lassen JF, Chieffo A, Lefevre T, Stankovic G, et al. The EBC TWO Study (European Bifurcation Coronary TWO): A randomized comparison of provisional t-stenting versus a systematic 2 stent culotte strategy in large caliber true bifurcations. Circ Cardiovasc Interv 2016;9(9):003643. [Crossref]

Figure and Tables

Figure 1. Log CSS calculation criteria. CrCl: Creatinin clearence, LV: Left ventricle.
Figure 2. Comparison of two-year clinical outcomes of high and low log CSS groups. MI: Miyocardial infarction, TLR: Target lesion revascularization, TVR: Target vessel revascularization, CV: Cardiovascular, MACE: Major adversc cardiovascular event.
Figure 3. Kaplan-Meier curves for survival at two-year follow-up after index procedure according to whether log CCS is high or low.
Figure 4. Long-term risk prediction with ROC curve of Log CCS and SS. CSS: Clinical SYNTAX score, AUC: Area under the curve, CI: Confidence interval.
Table 1. Comparison of characteristics of study patients with Log CSS
Table 1. Comparison of characteristics of study patients with Log CSS (continued)
Table 2. Univariable and multivariable logistic regression analyzes for the development of MACE
Table 3. Multivariable logistic regression analysis for the development of MACE in different stenting strategies