Value of Duke treadmill score in predicting coronary artery lesion and the need for revascularisation

Abstract

Background: Exercise electrocardiography is a long-standing method for the evaluation of coronary artery disease (CAD), and it remains the initial test for most patients who can exercise adequately with a baseline interpretable electrocardiogram. However, there is little information about the relationship between Duke treadmill test score (DTS) and severity of coronary artery lesion, as well as estimating the need for revascularisation.

Aim: The aim of the study was to ascertain whether the DTS could be an efficient parameter in choosing coronary revascularisation in different DTS groups.

Methods: Two hundred and fifty-eight (n = 258) patients had positive exercise testing for CAD and underwent coronary angiography. The patients were divided into three groups according to the DTS: low-risk (with a score of ≥ +5), moderate-risk (with scores ranging from -10 to +4), and high-risk (with a score of ≤ -11). Coronary angiography was done by the Judkins technique. A coronary lesion was considered significant when stenosis of the coronary artery was ≥ 70% and stenosis of the trunk was ≥ 50%. The SYNTAX score was determined.

Results: The study group included 258 patients with mean age 62.66 ± 9.6 years, and most of them were men (72.8%). Patients with high- and intermediate-risk DTS had the same SYNTAX score (16.35 ± 7.3, 15.09 ± 10.08 and 11.80 ± 9.88, respectively; p = 0.064) compared to low-risk DTS. A negative correlation between DTS and significant coronary artery stenosis (r = -0.181; p = 0.005), SYNTAX score (r = -0.173; p = 0.007), and cardiac revascularisations (r = -0.213; p = 0.001) were found. In multiple linear regressions to predict coronary revascularisation the SYNTAX score (B = 0.018; p = 0.0001), DTS (B = -0.014, p = 0.008) and previous myocardial infarction (B = -0.143; p = 0.047) were significant predictors.

Conclusions: The DTS alone is a useful tool in suspecting a significant coronary artery stenosis, but it is not accurate enough for revascularisation. Thus, by adding clinical information, its value may be maximised.

Keywords: Duke treadmill score; SYNTAX score; exercise stress test; previous cardiovascular outcomes; revascularisation.