Limited value of recovery phase-limited ST segment depression of treadmill exercise test

Background Clinical meaning of recovery phase limited ST segment depression of a treadmill exercise test is controversial.The aim of this study was to re-assess the diagnostic and prognostic value of ST segment depression during the recovery phase with the active phase of a treadmill exercise test in suspected coronary artery disease patients.Methods Clinical,exercise and angiographic data were retrospectively collected from 602 patients in the study.Five hundred and seventy-six patients developed ST segment depression during the active phase of the treadmill exercise test （group 1） and 26 patients developed ST segment depression only during the recovery phase （group 2）.Results With similar major clinical features,the prevalence of significant coronary artery stenosis and average Gensini scores were lower in the recovery phase-limited depression patients （group 2 vs.group 1,50.0% vs.66.9%,P=0.031 and group 2 vs.group 1,1.5 vs.8.5,P=0.04）.At a median follow up of 50.9 months for 22 group 2 and 34.8 months for 438 group 1 patients,the prevalence of total cardiac events was higher in group 1 than in group 2 patients （RR 1.60,95% Cl 1.00-2.54,P=0.049）.Conclusion The present study provides preliminary evidence that the diagnostic and prognostic value of recovery phaselimited ST segment depression of treadmill exercise test is limited.

Rehabilitation training improves exercise tolerance after percutaneous coronary intervention

The aim of this present study was to investigate the effects of training on exercise tolerance of patients with coronary heart disease after percutaneous coronary intervention.Fifty-seven cases of coronary heart disease after percutaneous coronary intervention were divided randomly into the rehabilitation training group（26 cases） and control group（31 cases）.Patients in the rehabilitation training group received rehabilitation training at different stages and exercise intensities 3 d after percutaneous coronary intervention for 3 months.The heart rate,blood pressure,ECG changes in treadmill exercise test,and the frequency of anginal episodes were observed.The results showed that NST and ΣST of ECG and the frequency of anginal episodes were significantly reduced in the rehabilitation training group.In addition,exercise tolerance was improved and the total exercise time was lengthened in these patients.Moreover,ST segment depression time and emergence time of angina with exercise were also lengthened compared with controls（P 〈 0.05,or 0.01）.However,the heart rate and blood pressure before and after exercise of the two groups were similar.The study indicated that rehabilitation training could significantly relieve angina,amend ischemic features of ECG,and improve exercise tolerance of coronary heart disease patients after percutaneous coronary intervention.

Predictive treadmill score to identify coronary artery disease

Background Exercise treadmill testing（ETT） is widely used for the diagnosis of coronary artery disease（CAD）.The high false-positive and false-negative rates hamper its clinical application.Hypothesis：We examined a hypothesis that combined ETT and risk-factors of CAD to develop an easily applied predictive treadmill score（PTS） and the superiority of the novel score over the conventional ETT criteria was tested.This score can improve the diagnostic accuracy of treadmill testing for Chinese patients with suspected CAD and plan management strategies for such patients.Methods The present study comprised a retrospective analysis of 300 ETTs of Chinese patients with chest pain referred to suspected CAD who also had coronary angiography within one month after ETT.Clinical characteristics and ETT results of those with and without angiographic CAD were compared.A logistic regression model was used to construct a PTS that could accurately predict clinically significant CAD,defined as the presence of at least one 〉 70 % angiographic stenosis in a major epicardial coronary artery.The accuracy of the new PTS was compared to conventional criteria of ETT for CAD diagnosis.Results The study included 185 patients with clinically significant CAD（61.6 %） and 115（38.4 %） without CAD.Patients with significant CAD were older,more cigarettes smokers,and had higher prevalence of hypercholesterolemia,diabetes mellitus and serum CRP concentration.The PTS for CAD was derived from the logistic regression equation：Y（-1,1） =-6.94 ＋ 0.07Age ＋ 0.56Smoking ＋ 0.7DM ＋ 0.6TC /HDL ＋ 0.6ST ＋ 3.5Symptom-0.01HR.According to the derived Y value,the study subjects were classified as low,intermediate and high risk CAD groups,if Y 〈-1,-1 ≤ Y ≤ 1,and Y 〉 1 respectively.The area under the curve（AUC） of our PTS on the receiver operating curve（ROC） was 0.863.Using the PTS,the specificity,false-positive rate and the predictive accuracy for CAD detection were significantly improved compared to conventional ETT diagnostic criteria（73.6% vs.56.9%;26.4% vs.43.1%;77.6% vs.71.8%,P 〈 0.05）.Conclusions A new predictive treadmill score for CAD diagnosis was validated and found superior to the conventional criteria of ETT for the diagnosis of CAD in Chinese patients presenting with chest pain.