A Study On The Diagnostic Value Of Treadmill Test In Coronary Disease

Objective:Our aim is to study the relationship between coronary disease and some parameters in the treadmill exercise test(TET).Furthermore we will discuss the strategies to increase the diagnostic value of TET in women.Methods:Our study included 188 patients who underwent both TET and coronary angiography in Huashan Hospital between 2004 and 2007.We evaluated the diagnostic value of TET's classic positive standards.After that we calculated each patient's Duke treadmill score[DTS=exercise time-5~*ST deviation-4~*exercise angina (with 0=none,1=non-limiting angina,and 2=exercise-limiting angina)]and post-exercise systolic blood pressure ratio(dividing the systolic blood pressure after three minutes into the recovery phase of a treadmill exercise test by the systolic blood pressure at peak exercise).Then we analyzed whether the two parameters are related to the prevalence of coronary disease(especially in women).Finally we studied the positive leads in TETs in order to verify their relationship with the stenosis of a particular coronary artery.Results:TET has a sensitivity,specificity,positive predictive value,negative positive value of 69.2%,54.5%,51.9%,71.4%,respectively.Its sensitivity,specificity, negative positive value show no statistic difference between men and women,while the positive predictive value is lower in women(P=0.014).Patients with coronary disease have a mean Duke treadmill score of -2.25±6.3,patients without coronary disease 0.75±4.2,P＜0.001.We divide all patients into low-risk(with a score of＞or=to+5),moderate-risk(with scores ranging from -10 to +4),and high-risk(with a score of＜or=to-11) group.Patients in each group have different severity of coronary artery stenosis(P＜0.001),both in men and women.In the same risk group(i.e. moderate-risk group),women often have lighter coronary artery stenosis than women. Patients with coronary disease have a mean post-exercise systolic blood pressure ratio of 0.88±0.14,patients without coronary disease 0.83±0.14,P=0.013.In patients with a positive result in TET,higher post-exercise systolic blood pressure ratio than 0.9 indicates larger probability of coronary disease,both in men and women.The positive leads in TETs are oftenⅡ,Ⅲ,avF,V4,V5 and V6,which have nothing to do with the stenosis of a particular coronary artery(P=0.911).Conclusions:TET's classic positive standards have a pretty good sensitivity,while the specificity and positive predictive value is rather low,especially for the positive predictive value in women.Duke treadmill score has the predictive value for the severity of coronary artery stenosis.In patients with a positive result in TET,higher post-exercise systolic blood pressure ratio than 0.9 can help to establish the diagnosis of coronary disease.Duke treadmill score and post-exercise systolic blood pressure ratio are also helpful in the diagnosing coronary disease in women.The positive leads in TETs do not correspond with the stenosis of a particular coronary artery.