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...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.展开更多
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 determ...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展开更多
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 magnetoc...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.展开更多
Objective: To examine the reproducibility of HRR in healthy individuals with slow HRR response undergoing routine annual checkups. Method: HRR data (>18 b/min;Group 1 and 18 b/min;Group 2) were analyzed using ...Objective: To examine the reproducibility of HRR in healthy individuals with slow HRR response undergoing routine annual checkups. Method: HRR data (>18 b/min;Group 1 and 18 b/min;Group 2) were analyzed using a fixed-effects regression model adjusted for age and gender, including random effects group-specific slopes on age. Results: One hundred and thirteen individuals (56.5 ± 9.2 y), underwent 573 cumulative ESTs with an average of 5.1 ± 1.6 tests per individual during a 21-year retrospective follow-up. No differences were found in anthropometric measurements and blood variables. All individuals achieved 94% ± 7.7% of age-predicted HR max at peak EST. Group 2 demonstrated 38% of inconsistent HRR. Regression analysis demonstrated a decrease of 0.5 b/min, on average across individuals, in HRR per each extra year of age. The random effects showed an inter-subject SD level of 9.91 b/min and an SD on the age slope of 0.40 b/min/year. Conclusion: HRR showed low reproducibility in nearly 40% of tests, which was not reflected by the variation of HR nor in the slope of age during a 21-year retrospective follow-up.展开更多
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 ...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.展开更多
文摘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.
文摘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
文摘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.
文摘Objective: To examine the reproducibility of HRR in healthy individuals with slow HRR response undergoing routine annual checkups. Method: HRR data (>18 b/min;Group 1 and 18 b/min;Group 2) were analyzed using a fixed-effects regression model adjusted for age and gender, including random effects group-specific slopes on age. Results: One hundred and thirteen individuals (56.5 ± 9.2 y), underwent 573 cumulative ESTs with an average of 5.1 ± 1.6 tests per individual during a 21-year retrospective follow-up. No differences were found in anthropometric measurements and blood variables. All individuals achieved 94% ± 7.7% of age-predicted HR max at peak EST. Group 2 demonstrated 38% of inconsistent HRR. Regression analysis demonstrated a decrease of 0.5 b/min, on average across individuals, in HRR per each extra year of age. The random effects showed an inter-subject SD level of 9.91 b/min and an SD on the age slope of 0.40 b/min/year. Conclusion: HRR showed low reproducibility in nearly 40% of tests, which was not reflected by the variation of HR nor in the slope of age during a 21-year retrospective follow-up.
文摘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.
