The Implication of Duke Treadmill Score (DTS) on the Extent of Coronary Artery Lesions by Angiography

Tariq Mutasher Swadi,Mazin Zamil Alshibani,Usama Kadum Kredi
Authors Emails are requested on demand or by logging in
Keywords : CAD, Duke treadmill score
Medical Journal of Babylon  13:2 , 2016 doi:1812-156X-13-2
Published :11 September 2016

Abstract

Exercise testing is used to evaluate patients with coronary artery disease. The Duke treadmill score (DTS) is a composite index for diagnostic and prognostic estimates based on results of the exercise test. A cross sectional study used to assess patients referred to The Iraqi Centre for Heart Diseases with chest pain by exercise test and coronary angiography during the period from May 2013 to April 2014. A significant coronary artery lesion: ?50% left main stem stenosis or, ?70% stenosis in other epicardial vessels. Significant lesion in the left main stem or three vessels defines an extensive coronary artery disease (CAD). Non extensive disease means significant lesion in one or two vessels. 80 patients included in the study (40 patients with high risk DTS, and 40 patients with non-high risk DTS). 61 patients were males (76%), 19 patients were females (24%). 38 patients of the high risk group (95%) had a significant coronary artery disease, 13 patients of them (32%) had extensive coronary artery disease. More than half of the non-high risk group (58%) had no coronary lesion, 17 patients (42%) with significant coronary disease, with one patient with extensive coronary disease (P?0.001). The Duke treadmill test provides diagnostic and prognostic information for the evaluation of symptomatic patients for clinically suspected ischemic heart disease.

Introduction

CADhas been remaining the first killer and the major cause of public health problems in the world, which is one of the most common causes of morbidity and mortality in different communities, moreover, CAD is the main cause of death in the United States of America among human adults representing approximately one-third of all dead people, who are over the age of 35 years[1].The CAD mortality in North America and Western Europe in the recent decades has been successfully reduced by the treatment, while in contrast, it has increased in Asia and Eastern Europe [2].Coronary artery disease development and progression is stimulated by genetic and/or genetic or other factors; among these factors are tobacco use, diabetes mellitus (DM), and hypertension [3]. In most cases, CAD has a multifactorial genetic basis, involving a number of genes and environmental factors, which are interacting to determine whether or not the disease will develop as well as its severity[4].

Materials and methods

This was a cross sectional study conducted at the Iraqi Centre for Heart Diseases; the main cardiac center in the Medical City Teaching Hospital in Baghdad.
Patients
   The sample which was collected over the period from May 2013 to April 2014 consisted of 102 patients. 22 patients were excluded, 15 patients with previous revascularization and 7 patients with LBBB on baseline ECG. Other exclusive criteria including: severe uncontrolled hypertension, acute coronary syndrome, aortic stenosis, decompensated heart failure, uncooperative patients, and patients with leg disability. The remaining 80 patients underwent exercise ECG testing for clinical suspicion of CAD based on intermediate &high pretest probability for CAD by age, gender, and symptoms followed by coronary angiography study as a part of risk stratification according to the ACC/AHA guidelines.
80 patients were included in this study, 19 patients were female (10 patients with high risk and 9 patients with non-high risk) and 61 patients were male (30 patients with high risk and 31 patients with non-high risk).
All patients underwent symptom-limited treadmill exercise testing according to the standard Bruce protocol by using Tepa Pro_2200/2011 machine.Exercise testing was discontinued if exertional hypotension, malignant ventricular arrhythmias, marked ST depression (?3 mm), or limiting chest pain was reported. An abnormal exercise ST response was defined as ?1 mm of horizontal or downsloping ST depression at (J-point+60 ms). The Duke treadmill score(DTS) was calculated as the following: DTS= exercise time (minute) ? 5 ×(maximum ST deviation) ? 4× (treadmill angina index). Angina index =0 ifnoanginal pain during exercise, 1for non-limiting anginal pain, 2if angina was why the test terminated. A (DTS) of ?  ? 11 was defined as high risk , a DTS of >  ? 11 to + 5 was defined as intermediate risk , while a score of >  +5 was defined as low risk [5].
A significant coronary artery lesion by angiography was defined as follows: ? 50% left main stem stenosis or, ?70% stenosis in other epicardial vessels. The presence of a significant lesion in the left main stem or three epicardial vessels was labeled as extensive coronary artery disease, while non-extensive coronary artery disease indicates a significant lesion in one or two epicardial vessels[6].
Statistical analysis
  Was performed by using the SPSS version 20, IBM, US, 2010. Descriptive statistics were presented as mean and SD for the age, and frequencies and proportions for other variables. Student’s t test was used to compare DTS risk groups, coronary artery lesions subtypes, and mean ST changes. Chi square test (X2) was used to assess the significance of associations between variables. Level of significance (P.value) ? 0.05 was considered significant. Finally all findings and results were presented in tables.



Ethical Considerations
1.    The study protocol was approved by the Faculty of Medicine and the Committee of postgraduate studies of University of Baghdad.
2.    Verbal consent of patients was obtained prior to participations.
3.    Data including the names and identifications information of the patients were kept in a secured database and weren’t disclosed to unauthorized individuals.




Results

There were 80 patients included in the study (40 patients were with high risk DTS, the other 40 were with non-high risk DTS). The mean age 55.6 ±9.6 years. 61 patients were males (76.0%) and 19 were females (24.0%). There was no significant difference in age groups and means between males and females (p>0.05), as shown in table1.The main risk factors for CAD among study participants were HT (65%), DM (34.0%) and smoking (43.0%). Participants who had one risk factor represented 40%, those who had two risk factors represented 26.0%, those who had no risk factors represented 18.0% and those who had three risk factors represented 16.0%, as shown in table 2.

Discussions

The prognostic evaluation is a crucial component of clinical evaluation of patients with CAD. Although patients with stable angina have low mortality rate, the risk of myocardial infarction, the need for interventions and the symptoms all affect the clinical evolution of the disease[7-10]. Demographic presentation of the present study revealed that males were more than females and the mean age of females was higher than that of males although, no significant difference was observed in age groups and mean age between males and females (p>0.05). This finding is consistent with results of Saeed et al study in Iraq, [11] and Assiri[12].The present study revealed that half of study participants had high risk DTS and other half had non-high risk DTS, this finding is close to that reported by Liao L et al in USA [13], and Shaikh et al[14]. In the present study about one-third of the patients had no vessels involved, other two thirds had from one to three vessels, on the other hand, the extent of CAD was: extensive for 18.0%, non-extensive for 51.0% of the patients, and no lesion for 31.0%,the left main stem involvement was non 0.0% . This picture is close to the results of other two studies in USA; Kwok et al study [15], and Lauer MS study [5], in regard to three vessel involvement while it was inconsistent in regard to left main stem involvement, this inconsistency might be attributed to the small sample size in our study, and interobserver and intraobserver variation in the quantification of LMS lesion. The sex in the present study did not significantly affect the outcome of DTS (p=0.79). This finding is inconsistent with that found in other study was carried out by Jang JY et al study in South Korea [16], and an earlier study was conducted by Shaw LJ et al in USA [17] that found significant association between sex and DTS, the inconsistency with these studies might be attributed to the small number of females compared to males in our study. This study revealed a significant association of DTS with old age (p=0.001). This finding is in line with the results of Shaw et al [17] and Marwick et al[18].The present study revealed a significant association between high risk DTS and the extent CAD (p<0.001). This finding is consistent with results of Acar et al [19] that concluded a strong correlation between high risk DTS and coronary lesion complexity. Shaw et al study in USA [17]found also a significant association between high risk DTS with extensive and significant CAD.A significant association was observed by this study between non-high risk patients and no lesion detected by angiography (p<0.001). This finding is consistent with results of Tamargo et al[20] that resulted high sensitivity and specificity of DTS indiagnosis and prognosis of CAD lesions. Limitations of The Study 1. Small sample size. 2. Inter and intraobserver variability in the exercise ECG interpretation and angiographic lesion quantification. 3. Referral bias.

Conclusions

DTS is a significant diagnostic and prognostic tool for CAD.A significant association between DTS and elderly age.High risk DTS had a significant association with extensive, and significant CAD, and S-T segment depression on ECG.Non high risk group patients had more association with no lesions by angiography and almost no extensive CAD.

References

1. Hadaegh F, Harati H, Ghanbarian A, Azizi1 F. Prevalence of coronary heart disease among Tehran adults: Tehran Lipid and Glucose Study Eastern Mediterranean Health Journal(2009),15, No. 1.
2. Fakhrzadeh H, Bandarian F, Adibi H, Samavat T, MalekafzaliH, Hodjatzadeh E and Larijani B. Coronary heart disease and associated risk factors in Qazvin: a population-based study, Eastern Mediterranean Health(2008), 321:543.
3. Stocker R, John F, Keaney J. Role of Oxidative Modifications in Atherosclerosis, Physiol. (2004) Rev. 84: 1381-1478.
4. Freitas A, Mendonça I, Bri?n M, Sequeira M, Reis R, Carracedo A and Brehm A. RAS gene polymorphisms, classical risk factors and the advent of coronary artery disease in the Portuguese population BMC Cardiovascular Disorders (2008):15 doi:10.1186/1471-2261-8-15.
5. Lauer MS. The exercise treadmill test: Estimating cardiovascular prognosis. Cleveland Clinic Journal of Medicine 2008; 75 (6): 424-430.
6. Serruys PW, MoriceMC,KappeteinAP,et al. Percutaneous coronary intervention versus CABG surgery for severe coronary artery disease.NEngl j Med 2009;360:1-72.
7. Yusuf S, Sleight P, Pogue J, Bosch J, Davies R, Dagenais G. Effects of an angiotensin-converting-enzyme inhibitor, ramipril, on cardiovascular events in high-risk patients: the heart outcomes prevention evaluation study investigators. N Engl J Med. 2007; 342(3):145-53.
8. Fox KM. Efficacy of perindopril in reduction of cardiovascular events among patients with stable coronary artery disease: randomised, double-blind, placebo controlled, multicentre trial (the EUROPA stud-y). Lancet. 2003; 362(9386):782-8.
9. Poole-Wilson PA, Lubsen J, Kirwan BA, van Dalen FJ, Wagener G, Danchin N, et al. Effect of long-acting nifedipine on mortality and cardiovascular morbidity in patients with stable angina requiring treatment (ACTION trial): randomised controlled trial. Lancet. 2004; 364(9437):849-57.
10. Yamada H, Do D, Morise A, Atwood JE, Froelicher V. Review of studies using multivariable analysis of clinical and exercise test data to predict angiographic coronary artery disease. Prog Cardiovasc Dis. 2007; 39(5):457-81.
11. Saeed ID, Abdulmajeed MA. Gender effect on coronary angiographic findings in evaluation of chest pain.AnnColl Med Mosul 2013; 39 (2): 147-153.
12. Assiri AS. Gender di?erences in clinical presentation and management of patients with acute coronary syndrome in Southwest of Saudi Arabia. Journal of the Saudi Heart Association 2011; 23: 135-141.
13. Liao L, Smith IVW, Tuttle RH, Shaw LK, Coleman RE, Borges-Neto S. Prediction of Death and Nonfatal Myocardial Infarction in High-Risk Patients: A Comparison Between the Duke Treadmill Score, Peak Exercise Radionuclide, Angiography, and SPECT Perfusion Imaging. J Nucl Med 2005; 46:5-11.
14. Shaikh AH, Hanif B, Hassan K. Correlation of Duke s treadmill score with gated myocardial perfusion imaging in patients referred for chest pain evaluation. J Pak Med Assoc 2011; 61 (8): 273-276.
15. Kwok JM, Miller TD, Hodge DO, Gibbons RJ. Prognostic value of the Duke treadmill score in the elderly. Journal of the American College of Cardiology 2002; 39 (9): 1475-1481.
16. Jang JY, Sohn IS, Kim JN, RN, Park JH, Park CB, et al. Treadmill Exercise Stress Echocardiography in Patients With No History of Coronary Artery Disease: A Single-Center Experience in Korean Population. The Korean Society of Cardiology 2011: 528-534.
17. Shaw LJ, Peterson ED, Shaw LK, Kesler KL, DeLong ER, Harrell FE Jr, Muhlbaier LH, et al. Use of a prognostic treadmill score in identifying diagnostic coronary disease subgroups. Circulation 2004; 98:1622-30.
18. Marwick TH, Case C, Vasey C, Allen S, Short L, Thomas JD. Prediction of Mortality by Exercise Echocardiography: A Strategy for Combination with the Duke Treadmill Score. Circulation 2007; 103:2566-2571.
19. Acar Z, Korkmaz L, Agac MT, Erkan H, Dursun I, Kalaycioglu E, et al. Relationship between Duke Treadmill Score and Coronary Artery Lesion Complexity. ClinInest Med 2012; 35 (6): E365-E369.
20. Tamargo AJ, Martin-Ambrosio ES, Tarin ER, Fernandez MM, Tassa CM. Significance of treadmill scores and high risk criteria for exercise testing in non-high-risk patients with unstable angina and an intermediate Duke treadmill score. ActaCardiol 2008; 63 (5): 557-564.


The complete article is available as a PDF File that is freely accessible. The fully formatted HTML version can be viewed as HTML Page.

Medical Journal of Babylon

volume 13 : 2

Share |

Viewing Options

Abstract
Download Abstract File
( 135 KB )

Related literature

Cited By
Google Blog Search
Other Articles by authors

Related articles/pages

On Google
On Google Scholar
On UOBabylon Rep

User Interaction

394  Users accessed this article in 1 year past
Last Access was at
18/10/2017 10:32:24