Validity of SYNTAX score II for risk stratification of percutaneous coronary interventions: A patient-level pooled analysis of 5433 patients enrolled in contemporary coronary stent trials
Introduction
The SYNTAX score [1], [2], [3] was developed for the randomized comparison of coronary artery bypass grafting (CABG) versus percutaneous coronary intervention (PCI) in the Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) trial [2]. The SYNTAX score provides objective quantification on the diseased coronary artery segment in terms of its severity, anatomical location and importance in supplying blood to the myocardium. Based on the results of the SYNTAX trial [2], [4], [5] the SYNTAX score has been implemented as a watershed between CABG and PCI in prevailing guidelines [6], [7]. However, the SYNTAX score cannot account for the effect related to clinical factors which are widely acknowledged to impact on long-term outcomes, such as a patients' age, left ventricular ejection fraction, and renal function [8], [9], [10].
Recently, the SYNTAX score II was developed by applying a Cox proportional hazards model to the SYNTAX trial data. A combination of clinical and anatomical predictors [5], [11], together with their interaction with the treatment modality (CABG or PCI), enables estimation of the absolute risk difference between CABG and PCI and has the potential to assist the multidisciplinary decision-making process between these two strategies. The SYNTAX score II has been shown to provide reliable predictions of 4-year mortality for complex coronary artery disease, being externally applied in more than 10,000 patients and implemented in the most recent international guidelines [11], [12], [13], [14].
We aim to assess the stratification by the SYNTAX score II theoretical treatment recommendation in heterogeneous patients treated with PCI. Additionally, we intend to evaluate the predictive performance of the SYNTAX score II in recent randomized trials in different clinical scenarios using different types of stents.
Section snippets
Study population
We pooled 7 contemporary coronary drug-eluting stent (DES) trials for which the independent core lab analysis assessment of SYNTAX scores were available: ARTS II (Arterial Revascularization Therapies Study II) trial, STRATEGY (Single High-Dose Bolus Tirofiban and Sirolimus-Eluting Stent Versus Abciximab and Bare-Metal Stent in Myocardial Infarction) trial, EXCELLA II (Elixir Medical Clinical Evaluation of the Novolimus-Eluting Coronary Stent System) trial, LEADERS (Limus Eluted From a Durable
Results
As shown in Table 1, pooled data from the seven trials contained 5433 patients with a mean age 63.3 ± 10.8 years, 75.3% were male, 21.8% had diabetes mellitus, 56.8% presented acute coronary syndrome and the mean body mass index was 27.52 ± 4.1. The mean creatinine clearance was 92.1 ± 36.2 mg/dl, ejection fraction 56 ± 11.1% and SYNTAX score 14.2 ± 9.1. There were 399 deaths (6.3%) over 3-year follow-up.
Discussion
The data presented in this paper can be summarized as follows: (1) the SYNTAX score II based treatment recommendation for CABG was an uncommon finding in contemporary DES trials and (2) the SYNTAX score II showed clinical relevance through its ability to identify patients at higher risk for PCI.
Limitations
This study has the inherent limitations of a not pre-specified retrospective analysis. As previously discussed, the ultimate objective of the SYNTAX score II is to assist the heart team in the decision-making process between CABG and PCI [22]. Thus true validation of the SYNTAX score II would require a prospective study where the decision between CABG and PCI is done randomly. The present study, being retrospective, cannot assess the treatment recommendation based on the SYNTAX score II for the
Conclusions
The SYNTAX score II demonstrated solid predictive performance and aptness to help in stratifying and prescribing PCI procedures.
Conflict of interest
All authors have no conflict of interest and did not receive grants or financial support from industry or from any other source to prepare this manuscript.
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2021, Indian Heart JournalCitation Excerpt :These findings suggest that both cSS and SSII are useful tools in routine clinical decision making, helping in the individualized and more precise assessment of post-ACS patients undergoing PCI.20,21 SSII has been validated in different trials; however, limited data exists comparing different risk scores in UA/NSTEMI patients.24–26,30–32 The present study could compare and evaluate the SSII in UA/NSTEMI patients undergoing multivessel PCI.
The association of the Syntax score II with carotid intima media thickness and epicardial fat tissue
2017, Indian Heart JournalCitation Excerpt :Various studies have showed that coronary complexity is associated with surrogate markers, which may have a role on coronary atherosclerosis pathophysiology via the paracrine or autocrine effect. However, those previous studies employed either the Gensini scoring system or older risk classification systems.15–23 Also, the association between SSII and surrogate markers had not been proven, yet.
Estimation of myocardial flow reserve utilizing an ultrafast cardiac SPECT: Comparison with coronary angiography, fractional flow reserve, and the SYNTAX score
2017, International Journal of CardiologyCitation Excerpt :A FFR < 0.8 was considered abnormal [2]. Additionally, each coronary lesion that produced a luminal narrowing ≥ 50% in vessels ≥ 1.5 mm in diameter was separately scored using the SYNTAX score calculator, and then summed to provide an overall SYNTAX score [23,24]. Continuous variables are expressed as means and 95% confidence intervals (CIs).
ApPropriateness of myocaRdial RevascularizatiOn assessed by the SYNTAX score II in a coUntry without cardiac Surgery faciliTies; PROUST study
2017, International Journal of CardiologyCitation Excerpt :As aforementioned, this score could assist the Heart Team in the decision-making process between two revascularization strategies [7–9]. In the recently published pooled analysis from 7 contemporary PCI trials (n = 5433) authors stratified patients according to the SSII recommendation, and concluded, similarly to the present study [23]. Our findings underline the concept that the decision between CABG and PCI in complex CAD should, in addition to anatomical characteristics, balance the clinical characteristics and risks that may favour one therapy over the other.
Usefulness of SYNTAX score II in complex percutaneous coronary interventions in the setting of acute coronary syndrome
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2016, Interventional Cardiology ClinicsCitation Excerpt :At the time of writing this article, an online calculator is not available, which makes the workability of the SYNTAX score II suboptimal in daily practice. The score has been validated retrospectively in patients with left main disease105,106 and those undergoing all-comers PCI.107 However, one may advocate that for a score that acts as a decision-making tool, retrospective validation is insufficient (ie, a decision for a procedure over another has already been taken) and prospective validation is necessary (ie, the score should demonstrate the ability to assist in taking appropriate decisions that positively impact on the outcomes of patients selected for PCI or CABG).108