An Innovative Approach towards Selecting Aerobic and Coordinative Exercises in Clinical Practice for Children and Young People with ADHD

A growing body of studies and systematic reviews show evidence of the beneficial effects of physical exercise on core symptoms of ADHD. Furthermore, studies indicate that physical exercise as an adjuvant can enhance the effects of medication in the treatment of ADHD. Aerobic and coordinative exercises improve executive functioning through their effect on neurocognitive domains that are implicated in ADHD. It is postulated that through their specific modus operandi, aerobic exercise, by raising cortical arousal levels, improves impaired alerting functions whereas coordinative exercises improve the regulation of inhibitory control through the involvement of a higher variety of frontal-dependent cognitive processes. The increasing use of routine neurocognitive testing with continuous performance tests (CPT), such as the QbTest, at clinical assessments for ADHD allows for an innovative approach to identify the assessment impairments in alerting function and inhibition control that are related to ADHD and accordingly choose aerobic or coordinative physical exercise in a more targeted fashion.

Shortness of breath in clinical practice: A case for left atrial function and exercise stress testing for a comprehensive diastolic heart failure workup

The symptom cluster of shortness of breath(SOB) contributes significantly to the outpatient workload of cardiology services. The workup of these patients includes blood chemistry and biomarkers, imaging and functional testing of the heart and lungs. A diagnosis of diastolic heart failure is inferred through the exclusion of systolic abnormalities, a normal pulmonary function test and normal hemoglobin, coupled with diastolic abnormalities on echocardiography. Differentiating confounders such as obesity or deconditioning in a patient with diastolic abnormalities is difficult. While the most recent guidelines provide more avenues for diagnosis, such as incorporating the left atrial size, little emphasis is given to understanding left atrial function, which contributes to at least 25% of diastolic left ventricular filling; additionally, exercise stress testing to elicit symptoms and test the dynamics of diastolic parameters, especially when access to the "gold standard" invasive tests is lacking, presents clinical translational gaps. It is thus important in diastolic heart failure work up to understand left atrial mechanics and the role of exercise testing to build a comprehensive argument for the diagnosis of diastolic heart failure in a patient presenting with SOB.

Heart rate response and recovery during exercise predict future delirium risk——A prospective cohort study in middle-to older-aged adults

Background:Delirium is a neurocognitive disorder characterized by an abrupt decline in attention,awareness,and cognition after surgical/illness-induced stressors on the brain.There is now an increasing focus on how cardiovascular health interacts with neurocognitive disorders given their overlapping risk factors and links to subsequent dementia and mortality.One common indicator for cardiovascular health is the heart rate response/recovery(HRR)to exercise,but how this relates to future delirium is unknown.Methods:Electrocardiogram data were examined in 38,740 middle-to older-aged UK Biobank participants(mean age=58.1 years,range:40-72 years;47.3%males)who completed a standardized submaximal exercise stress test(15-s baseline,6-min exercise,and 1-min recovery)and required hospitalization during follow-up.An HRR index was derived as the product of the heart rate(HR)responses during exercise(peak/resting HRs)and recovery(peak/recovery HRs)and categorized into low/average/high groups as the bottom quartile/middle 2 quartiles/top quartile,respectively.Associations between 3 HRR groups and new-onset delirium were investigated using Cox proportional hazards models and a2-year landmark analysis to minimize reverse causation.Sociodemographic factors,lifestyle factors/physical activity,cardiovascular risk,comorbidities,cognition,and maximal workload achieved were included as covariates.Results:During a median follow-up period of 11 years,348 participants(9/1000)newly developed delirium.Compared with the high HRR group(16/1000),the risk for delirium was almost doubled in those with low HRR(hazard ratio=1.90,95%)confidence interval(95%CI):1.30-2.79,p=0.001)and average HRR(hazard ratio=1.54,95%CI:1.07-2.22,p=0.020)).Low HRR was equivalent to being 6 years older,a current smoker,or>3 additional cardiovascular disease risks.Results were robust in sensitivity analysis,but the risk appeared larger in those with better cognition and when only postoperative delirium was considered(n=147;hazard ratio=2.66,95%CI:1.46-4.85,p=0.001).Conclusion:HRR during submaximal exercise is associated with future risk for delirium.Given that HRR is potentially modifiable,it may prove useful for neurological risk stratification alongside traditional cardiovascular risk factors.

Serum oxidizability potential of ischemic heart disease patients is associated with exercise test results and disease severity

AIM:To find out whether serum oxidizability potential correlates with exercise test(EXT) parameters and predicts their results in chronic ischemic heart disease(IHD) patients.METHODS:Oxidizability potential was determined in a group of chronic IHD patients who underwent a symptom limited EXT upon initiation of a cardiac rehabilitation program.The thermo-chemiluminescence(TCL) assay was used to assess serum oxidizability potential.This assay is based on heat-induced oxidation of serum,leading to the formation of electronically excited species in the form of unstable carbonyls,which further decompose into stable carbonyls and light energy(low chemiluminescence).Measured photons emission is represented by a kinetic curve which is described by its amplitude and slope(= ratio).We assessed the correlations of TCL ratio with exercise duration,metabolic equivalents(METS),maximal heart rate(mHR),maximal systolic BP,> 1 mm S-T depression,diabetes,hypertension,smoking,left ventricular ejection fraction(LVEF) > or < 40%,previous myocardial infarction,and aorto-coronary bypass surgery and compared to the TCL ratio measured in a group of healthy controls.RESULTS:A high TCL ratio(%) correlated well with METS(r = 0.84),with mHR(r = 0.79) and with exercise induced S-T segment shift(r = 0.87,P < 0.05).A lower serum oxidizability potential,expressed as a low TCL ratio,thus suggestive of a previous high oxidative stress,was found in IHD patients compared to healthy controls,and,in particular,in patients with low LVEF%.The TCL ratio(%) in IHD patients was 193 ± 21,compared to 215 ± 13 in controls(P < 0.05),and was 188 ± 14.7 in patients with LVEF < 40% as compared to 200 ± 11.9 in those with LVEF > 40%(P < 0.01).A trend for lower TCL ratio(%) was found in diabetic,hypertensive,and post-coronary bypass surgery patients.A paradoxically low TCL ratio(low oxidizability potential) was observed in patients without S-T depression compared to patients with S-T depression(189 ± 22 vs 201 ± 15,P = NS),due to the fact these patients had a much lower LVEF% and a lower exercise capacity.CONCLUSION:Serum oxidizability potential is associated with EXT parameters,results,and IHD severity.TCL ratio is an "easy-to-measure marker" that might be incorporated into risk assessment and prediction in chronic IHD patients.

TWO METHODS TO IMPROVE THE ACCURACY OF TREADMILL EXERCISE TESTING──ANALYSIS OF 147 CASESIN CONTRAST WITH CORONARY ANGIOGRAPHY

objective To study how to improve the accuracy of treadmill exercise testing(TET).Methods TET was performed before coronary angiography (CAG) for 147 subjects admitted into our departmentbecause of suspicion of angina or coronary artery disease (CAD), then: (1) Every subject was inquired about hissymptoms and physically examined in detail before the testing. Chest pain was divided into ischemic (ICP) ornon - ischemic (NICP) pattern. (2) Informations got from TET, like angina, ST segment depression, and SPB ratio,were analyzed in detail. Results (1) When the patients showed chest pain of ICP pattern and positive TETresults, the sensitivity of TET would be 95%, for patients with NICP chest pain, the negative result of TET meansthat their coronary arteries is normal with the accurate possibility of 98%. (2) By our new criteria of TET, thesensitivity and specificity of TET were 89% and 95% respectively, both higher than those in theliterature. Conclusion in this report, we found TET was more sensitive and accurate if we knew the symptomsprior, especially in detail the characteristics of chest pain, and consider different parameters in combination.

Significance of Q-Tc,Q-Tr and A Q-Tc during Treadmill Exercise Test in Predicting Coronary Artery Disease

Seventy-eight patients underwent coronary angiography and submaximal tre-admill exercise test to evaluate the Q-Tc,Q-Tr and ΔQ-Tc criteria for predicting co-ronary artery disease(CAD).The sensitivity,specificity,predicting value and correctdiagnostic rate of the Q-Tc and Q-Tr criteria were 84,76,83,81 percent and 69,88,89,77 percent,respectively,which had no significant differences when compared with ST de-pression.The Q-Tc had higher specificity(94%)than that of ST depression but less sen-sitivity(58%).These criteria could reflect the severity of coronary artery disease identi-fied with coronary angiography.Therefore,these criteria are usefel to interpret the resultsof stress test.

Evaluation of Treadmill Exercise Test Induced U-wave Inversion in Diagnosis of Coronary Artery Disease

U-wave changes during treadmill exercise test were compared between 34 patientswith CAD and 33 normal controls.All of them were confirmed by coronary angiographv.Tenpatients with CAD and 1 normal subject in this study showed U-wave inversion during exercisetest.Of the 10 patients,4 had significant stenosis in one-vessel and 6 in multi-vessel of the ma-jor coronary arteries.The sensitivity,specificity and predictive value of exercise-inducedU-wave inversion were 29％, 97％ and 91％,respectively.It is proposed that exercise inducedU-wave inversion is a reliable predictive index of CAD.

Predictive value of preoperative cardiopulmonary exercise testing on early outcomes of pulmonary valve replacement after repair of Tetralogy of Fallot

Objective Cardiopulmonary exercise testing(CPET)is helpful to identify right ventriclar(RV)dysfunction in patients with rapair of Tetralogy of Fallot(rTOF),but its predictive value on early outcomes of pulmonary valve replacement(PVR)of these patients is unclear when similar preoperative ventricular size and function in cardiovascular magnetic resonance(CMR)exist.The aim of this study is to evaluate whether CPET is useful to predict the early outcomes of rTOF patients after PVR.

Prognostic Value of Cardiopulmonary Exercise Test in Elderly Women with Heart Failure and Reduced or Preserved Ejection Fraction

The prognostic role of cardiopulmonary exercise test (CPET) in elderly women with chronic heart failure (HF) has not yet been clarified. We assessed the incremental value of CPET variables for risk stratification in female HF patients with preserved or reduced left ventricular ejection fraction (LVEF). We prospectively followed up 131 female HF outpatients aged 72 [interquartile range 62 - 77] years after a symptom limited CPET. 34% had ischemic heart disease and 14% permanent atrial fibrillation, 24% were in NYHA class III. LVEF was 50% [interquartile range 36 - 62], peak oxygen consumption was 11.3 [interquartile range 9.2 - 13.5] ml/kg/min;the slope of the regression line relating ventilation to CO2 output was 33.9 [interquartile range 30.3 - 44.9];40% of patients showed exercise oscillatory breathing during CPET. During a median follow-up of 18 months [interquartile range 8 - 54], overall 39 patients (29.7%) met the combined end-point of cardiovascular mortality or HF admission using a time-to-first event approach. Moderate to severe mitral regurgitation, slope, exercise oscillatory breathing were independently associated to cardiovascular mortality or HF admission. When CPET ventilatory variables were added to clinical and echocardiographic parameters, prediction of the combined point improved significantly (AUC 0.755 (95% CI 0.662 to 0.832) vs 0.634 (95% CI 0.536 to 0.725), p = 0.016). In conclusion, among elderly female HF patients the CPET derived parameters EOB and VE/VCO2 slope emerged as strong prognostic markers, with additive predictive value to clinical and echocardiographic parameters in patients with both reduced and preserved LVEF.

New Parameters of Cardiopulmonary Exercise Testing in Patients with Chronic Heart Failure: Practical Applications

Cardiopulmonary exercise testing (CPX) has become the cornerstone of risk stratification for heart failure patients. Peak oxygen consumption (VO2) was the first CPX variable to demonstrate prognostic value and is still the most frequently analyzed variable in clinical practice. More recently, several investigations have shown that ventilatory efficiency, typically expressed as the minute ventilation/carbon dioxide production (VE/VCO2) slope, is a strong prognostic marker in patient with HF. The majority of studies report the VE/VCO2 slope to be prognostically superior to peak VO2 which underscore the clinical importance of assessing ventilatory efficiency in HF patients. Other expressions of ventilatory inefficiency like exercise oscillatory breathing (EOB), oxygen uptake efficiency slope (OUES), end-tidal carbon dioxide pressure (PET CO2) at rest, and haemodynamic responses such as heart rate recovery (HRR) are strong predictors of outcomes in patients with heart failure (HF). So there is a need for simplified approaches that integrate the additive prognostic information from cardiopulmonary exercise testing.

2D and 3D Analysis of Magnetocardiographic Data in the Evaluation of the Ventricular Repolarization Changes under Exercise Stress Test in Patients with CAD

Objective: Non-invasive methods of evaluation of electrical activity of the heart are still the most important functional diagnostics methods in coronary artery disease (CAD) detection. It has been shown that magnetocardiography (MCG) appears to be rather sensitive in diagnostics of chronic CAD even in the patients at rest with unchanged ECG. The objective of present paper is to investigate the influence of non-invasive tests with a physical exerciseon MCG parameters in the patients with chronic CAD. Materials and Methods: In total, 10 patients were examined (mean age 41 ± 5 years) suffering from chronic stable angina (CAD). CAD was diagnosed by clinical evidences, bicycle ergometria positive data and coronary angiography (stenosis > 70% in at least onr main coronary angiography). The control group consisted of 14 healthy volunteers. MCG mapping was performed by means of a 7-channel SQUID-magnetometer installed in an unshielded room. The MCG examination was conducted twice, whilst patients were at rest and after exercise on the bicycle (in healthy persons it was conducted immediately after exercise and in the patients, after the ST depression and/or chest pain had disappeared). The homogeneity and electric motive force (EMF) direction disturbances on magnetic field distribution maps on an extent of ST-T interval have been evaluated. Results: Statistically significant differences between groups examined based both on 2D and 3D quantitative criteria were demonstrated. Conclusion: The application of a set of MCG criteria based on the analysis both of ventricular depolarization and repolarization will enable a greater degree of accuracy for the results of the exercise stress test, especially in doubtful cases.

Preoperative Exercise Testing Is a Better Predictor of Postoperative Complications than Pulmonary Function Testing for Patients with Lung Cancer

Objective: The aim of this preliminary study was to evaluate the feasibility of exercise testing (ET) for predicting postoperative complications in patients with impaired pulmonary function. Methods: Thirteen patients were prospectively enrolled. The enrollment criteria were FEV1.0% 8 by the Goddard classification or interstitial pneumonia on chest computed tomography. Patients underwent testing for pulmonary function, six-minute walking test (6MWT), and stair-climbing test (SCT). Postoperative cardiopulmonary complications (PCPCs) were recorded. Results: Four patients developed PCPCs. There were no significant differences between the patients with PCPCs (n = 4) and those without PCPCs (n = 9) for background data and PFT. The distances achieved in the 6MWT were 503 ± 72.7 m for patients without PCPCs and 369 ± 50.7 m for patients with PCPCs (p = 0.011). The SCT climbing heights were 20.4 ± 5.3 m for patients without PCPCs and 14.9 ± 4.0 m for patients with PCPCs (P = 0.187). Cut-off points, including a 6MFT distance of less than 400 m, SCT height lower than 15 m, and SCT climbing speed less than 8.5 m/min, were predictive of CPCP. Conclusions: Exercise testing is more feasible for predicting postoperative cardiopulmonary complications than stationary pulmonary function testing.

QRS Prolongation as an Indicator of Risk of lschemic Ventricular Arrhythmia in Treadmill Exercise Test

Objective:The clinical value of QRS prolngation as a indicator of risk ofischemic ventricular arthythmia induced by exercise in the patient withischemic heart disease.Methods:17 case patients with ventricular arthythmias were studiedbefore and after myocardial revascularization.These results werecompared with 19 control patients with no ventricular arrhythmia.Theresting and peak exercise electrocardiogram were examined with respectto QRS duration,ST-segment depression,and JT intervals.Result:The QRS duration at rest was similar in case and control patientsand increased significantly with exercise in both groups.However,theQRS prolongation was larger in the case group.In both groups,the QRSprolongation was associated with significant ST-segment depression.TheQRS prolongation】15msec predicted ischimia-related ventriculararrhythmia in 73% of the patients.After myocardial revascularization,there were no QRS prolongation with exercise in either group.Conclusion:QRS prolongation】14msec may be a useful indicator of riskof ischemic ventricular arrhythmia related to exercise in the patients withtschemie heart disease.

Autonomic Function in Individuals with Slow Heart Rate Response following an Exercise Stress Test

Objective: To examine the autonomic function using HRV measures in apparently healthy individuals undergoing exercise stress test (EST) and demonstrating slow HRR response. Methods: HRV was measured with 12 lead ECGs during graded EST and analyzed via a post-processing method. Autonomic function was determined by Power Spectral Analysis of the very low frequency (VLF), low frequency (LF), high frequency (HF), and the ratio of LF/HF. We correlated HRV indices with resting, exercise, and recovery data. Results: No differences were found in anthropometric measurements, peak EST HR, and METS between individuals with slow HRR (below 18 b/min) compared with controls (HRR > 18 b/min). Only the VLF component of the HRV indices was statistically different (p = 0.03) at one-minute post-exercise compared with controls. Additionally, a significant correlation between HRR and resting LF and HF indices was found in the individuals with slow HRR but not in the controls. Conclusion: In apparently healthy individuals with slow HRR post-EST, autonomic function did not demonstrate any differences at any phase of the EST, including at one minute of recovery. However, a significant correlation was found between resting LF and HF powers and HRR in individuals with slow vagal reactivation post-exercise. The clinical and prognostic implications of such observation deserve further investigation.

Health Evaluation for Hypertensive Population Using Exercise Testing and Health-related Quality of Life Questionnaire

Objectives This study aims to assess the impacts of hypertension on health-related quality of life (HRQOL), as well as cardiovascular functional status (CVFS). Methods An instrument was presented based on WHOQOL-BREF and SP-16 questionnaire and exercise testing. 57 normotensive and 76 hypertensive subjects aged 35-65 year-old participated the health survey using this instrument. Based on the exercise testing results of the two groups, a discriminate function was established and used to investigate cardiovascular risk factors for hypertensive population. Results The results showed that persons with hypertension rated significantly lower scores on physical health (i.e. limitation in performing daily activities and problems with work or mobility) than did normotensives (P < 0.01). The discriminant score obtained from the exercise testing results was capable of reflecting the impacts of hypertension on CVFS. Conclusions The method presented in this paper provides a more powerful tool to estimate the effects of health interventions and medical therapy for hypertensive population than just self-rated HRQOL questionnaire.

Dead Space Breathing in Patients with Malignancies: Determination by Cardiopulmonary Exercise Testing

Rationale: Patients with cancer commonly experience dyspnea originating from ventilatory, circulatory and musculoskeletal sources, and dyspnea is best determined by cardiopulmonary exercise testing (CPET). Objectives: In this retrospective pilot study, we evaluated patients with hematologic and solid malignancies by CPET to determine the primary source of their dyspnea. Methods: Subjects were exercised on a cycle ergometer with increasing workloads. Minute ventilation, heart rate, breathing reserve, oxygen uptake (V’O2), O2-pulse, ventilatory equivalents for carbon dioxide and oxygen (V’E/V’CO2 and V’E/V’O2, respectively) were measured at baseline and peak exercise. The slope and intercept for V’E/V’CO2 was computed for all subjects. Peak V’O2 4% predicted indicated a circulatory or ventilatory limitation. Results: Complete clinical and physiological data were available for 36 patients (M/F 20/16);32 (89%) exhibited ventilatory or circulatory limitation as shown by a reduced peak V’O2 and 10 subjects with normal physiologic data. The largest cohort comprised the pulmonary vascular group (n = 18) whose mean ± SD peak V’O2 was 61% ± 17% predicted. There were close associations between V’O2 and spirometric values. Peak V’E/V’O2 and V’E/V’CO2 were highest in the circulatory and ventilatory cohorts, consistent with increase in dead space breathing. The intercept of the V’E-V’CO2 relationship was lowest in patients with cardiovascular impairment. Conclusion: Dyspneic patients with malignancies exhibit dead space breathing, many exhibiting a circulatory source for exercise limitation with a prominent pulmonary vascular component. Potential factors include effects of chemo- and radiation therapy on cardiac function and pulmonary vascular endothelium.

Exercise-Induced Bronchoconstriction Diagnostics:Impact of a Repeated Exercise Challenge Test

Exercise-Induced bronchoconstriction (EIB) is related to increased ventilation (VE) during exercise and describes the transient airway narrowing following exercise. A reliable diagnosis is essential for optimal treatment. The impact of a repeated exercise challenge test (ECT) in a clinical setting is not well established and conducting a repeated ECT with the possibility to adjust the exercise intensity on an individual basis may give more information. The aim of the study was to evaluate the test-retest reliability of an ECT for EIB and its association with exercise intensity. Methods: After examination by a pulmonologist, 20 referred subjects with symptoms strong indications of Exercise-Induced bronchoconstriction performed two consecutive exercise challenge tests on a treadmill. The exercise intensity of the repeated test was adjusted. Forced expiratory volume in 1 second (FEV1) was measured before and 1, 3, 6, 10, and 15 minutes after exercise. EIB was defined as a reduction of ≥ 10% in FEV1. Ventilation and heart rate were measured during exercise. Results: Five subjects tested positive in both tests, and ten subjects tested negative in both tests. Three subjects tested positive in the first test only, while two subjects tested positive in the second test only. The exercise intensity was not significantly different between the two tests for any of the subjects. Conclusion: There were 25% divergences in the diagnostic results of two consecutive exercise challenge tests. The difference in the test results was not explained by a difference in the exercise intensity.

Myocardial perfusion imaging in patients with a recent, normal exercise test

AIM: To investigate the added value of myocardial perfusion scintigraphy imaging (MPI) in consecutive patients with suspected coronary artery disease (CAD) and a recent, normal exercise electrocardiography (ECG). METHODS: This study was a retrospective analysis of consecutive patients referred for MPI during a 2-year period from 2006-2007 at one clinic. All eligible patients were suspected of suffering from CAD, and had performed a satisfactory bicycle exercise test (i.e. , peak heart rate > 85% of the expected, age-predicted maximum) within 6 mo of referral, their exercise ECG was had no signs of ischemia, there was no exercise-limiting angina, and no cardiac events occurred between the exercise test and referral. The patients subsequently underwent a standard 2-d, stress-rest exercise MPI. Ischemia was defined based on visual scoring supported by quantitative segmental analysis (i.e. , sum of stress score > 3). The results of cardiac catheterizationwere analyzed, and clinical follow up was performed by review of electronic medical files. RESULTS: A total of 56 patients fulfilled the eligibility criteria. Most patients had a low or intermediate ATPⅢ pretest risk of CAD (6 patients had a high pre-test risk). The referral exercise test showed a mean Duke score of 5 (range: 2 to 11), which translated to a low postexercise risk in 66% and intermediate risk in 34%. A total of seven patients were reported with ischemia by MPI. Three of these patients had high ATPⅢ pre-test risk scores. Six of these seven patients underwent cardiac catheterization, which showed significant stenosis in one patient with a high pre-test risk of CAD, and indeterminate lesions in three patients (two of whom had high pre-test risk scores). With MPI as a gate keeper for catheterization, no significant, epicardial stenosis was observed in any of the 50 patients (0%, 95% confidence interval 0.0 to 7.1) with low to intermediate pre-test risk of CAD and a negative exercise test. No cardiac events occurred in any patients within a median follow up period of > 1200 d. CONCLUSION: The added diagnostic value of MPI in patients with low or intermediate risk of CAD and a recent, normal exercise test is marginal.

Increases in the incremental exercise mean response time across the steady state domain:Implications for exercise testing&prescription

We hypothesized that slowed oxygen uptake(VO_(2))kinetics for exercise transitions to higher power outputs(PO)within the steady state(SS)domain would increase the mean response time(MRT)with increasing exercise intensity during incremental exercise.Fourteen highly trained cyclists(mean±standard deviation[SD]);age(39±6)years[yr];and VO_(2) peak=(61±9)mL/kg/min performed a maximal,ramp incremental cycling test and on separate days,four 6-min bouts of cycling at 30%,45%,65%&75% of their incremental peak PO(Wpeak).SS trial data were used to calculate the MRT and verified by mono-exponential and linear curve fitting.When the ramp protocol attained the value from SS,the PO,in Watts(W),was converted to time(min)based on the ramp function W to quantify the incremental MRT(iMRT).Slope analyses for the VO_(2) responses of the SS versus incremental exercise data below the gas exchange threshold(GET)revealed a significant difference(p=0.003;[0.437±0.08]vs.[0.382±0.05]L·min^(-1)).There was a significant difference between the 45%Wpeak steady state VO_(2)(ss VO_(2))([3.08±0.30]L·min^(-1),respectively),and 30% Wpeak ss VO_(2)(2.26±0.24)(p<0.0001;[3.61±0.80]vs.[2.20±0.39]L·min^(-1))and between the iMRT for 45% and 30% Wpeak ss VO_(2) values([50.58±36.85]s vs.[32.20±43.28]s).These data indicate there is no single iMRT,which is consistent with slowed VO_(2) kinetics and an increasing VO_(2) deficit for higher exercise intensities within the SS domain.

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.