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BackgroundThe utility of exercise-induced ST-segment depression for diagnosing ischemic heart disease (IHD) in women is unclear.HypothesisBased on evidence that IHD pathophysiology in women involves coronary vascular dysfunction, we hypothesized that coronary vascular dysfunction contributes to exercise electrocardiography (Ex-ECG) ST-depression in the absence of obstructive coronary artery disease, so-called false positive results. We tested our hypothesis in a pilot study evaluating the relationship between peripheral vascular endothelial function and Ex-ECG.MethodsTwenty-nine asymptomatic women without cardiac risk factors underwent maximal Bruce protocol exercise treadmill testing and peripheral endothelial function assessment using peripheral arterial tonometry (Itamar EndoPAT 2000) to measure reactive hyperemia index (RHI). The relationship between RHI and Ex-ECG ST-segment depression was evaluated using logistic regression and differences in subgroups using 2-tailed t tests.ResultsMean age was 54 ± 7 years, body mass index 25 ± 4 kg/m2 , and RHI 2.51 ± 0.66. Three women (10%) had RHI <1.68, consistent with abnormal peripheral endothelial function, whereas 18 women (62%) met criteria for positive Ex-ECG based on ST-segment depression in contiguous leads. Women with and without ST-segment depression had similar baseline and exercise vital signs, metabolic equivalents achieved, and RHI (all P > 0.05). RHI did not predict ST-segment depression.ConclusionsOur pilot study demonstrates high prevalence of exercise-induced ST-segment depression in asymptomatic, middle-aged, overweight women. Peripheral vascular endothelial dysfunction did not predict Ex-ECG ST-segment depression. Further work is needed to investigate the utility of vascular endothelial testing and Ex-ECG for IHD diagnostic and management purposes in women.

Background and Objectives: Coronary artery disease (CAD) remains the most common cause of death in Australia and is associated with significant social and financial cost to the community. We examined current Australian trends in investigations for the diagnosis of obstructive CAD for the past five years. Method(s): Statistics were retrieved from the Medicare database from January 2010 to January 2014 according to corresponding Medicare item numbers. Statistics were analysed per capita (services per 100,000 people) and by State / Territory. Australia-wide, usage of all modalities increased except stress ECG and nuclear imaging which declined steadily (from 745 to 634 per capita and 373 to 342 per capita respectively from 2010 to 2014). Stress echocardiography increased significantly becoming the most common investigation in 2014 (from 703 to 1009 per capita in 2010 to 2014). CT coronary angiography increased progressively from 50 to 177 per capita from 2011 to 2014. Despite an 18.7% increase per capita in non-invasive testing Australia wide over this period, invasive coronary angiography increased only 2.7% per capita. NSW performed substantially more non-invasive investigations of every modality than any other state or territory yet had comparable rates of coronary angiography (375 versus 322 per capita Australia wide for 2014). ACT and NT were consistently the lowest users of all diagnostic investigations. Conclusion(s): Despite progressive increases in non-invasive investigations for CAD including the introduction of CTCA in 2011, coronary angiography has remained stable. There remains a significant discrepancy per capita in cardiac investigations performed in the ACT and NT compared to other states.

Background and Objectives: Coronary artery disease (CAD) remains the most common cause of death in Australia and is associated with significant social and financial cost to the community. We examined current Australian trends in investigations for the diagnosis of obstructive CAD for the past five years. Method(s): Statistics were retrieved from the Medicare database from January 2010 to January 2014 according to corresponding Medicare item numbers. Statistics were analysed per capita (services per 100,000 people) and by State / Territory. Australia-wide, usage of all modalities increased except stress ECG and nuclear imaging which declined steadily (from 745 to 634 per capita and 373 to 342 per capita respectively from 2010 to 2014). Stress echocardiography increased significantly becoming the most common investigation in 2014 (from 703 to 1009 per capita in 2010 to 2014). CT coronary angiography increased progressively from 50 to 177 per capita from 2011 to 2014. Despite an 18.7% increase per capita in non-invasive testing Australia wide over this period, invasive coronary angiography increased only 2.7% per capita. NSW performed substantially more non-invasive investigations of every modality than any other state or territory yet had comparable rates of coronary angiography (375 versus 322 per capita Australia wide for 2014). ACT and NT were consistently the lowest users of all diagnostic investigations. Conclusion(s): Despite progressive increases in non-invasive investigations for CAD including the introduction of CTCA in 2011, coronary angiography has remained stable. There remains a significant discrepancy per capita in cardiac investigations performed in the ACT and NT compared to other states.

Visual and quantitative assessments of percent diameter stenosis on coronary angiography correlate poorly with functional testing, particularly in intermediate-severity (40%-70%) lesions, yet are frequently relied on to make decisions regarding revascularization. Coronary flow velocity reserve (CFVR) and relative CFVR (RCFVR) are promising methods for on-line functional assessment of lesion severity in the catheterization laboratory. We sought to determine the agreement between maximal, mean, and relative CFVR and stress echocardiography in intermediate-severity stenoses. The results of exercise or dobutamine stress echocardiography and CFVR measured by intracoronary Doppler were compared in 28 patients referred for assessment of intermediate-severity stenoses, using 15 patients with either angiographically normal coronary arteries or diameter stenoses > 70% as reference groups. CFVR was measured at least three times in response to a bolus of adenosine in the target vessel distal to the stenosis. RCFVR (target/normal vessel CFVR) was also measured in 27 patients. Maximal, mean (of three measures), and relative CFVR were calculated. CFVR >= 2.0 and RCFVR >= 0.75 were accepted as normal. A minority (29%) of patients in the intermediate-severity stenosis group had a positive test by either method. There was good to very good agreement between stress echocardiography and maximal CFVR (84%, kappa = 0.62, P < 0.0001) and RCFVR (81%, kappa = 0.59, P < 0.001) across the entire patient cohort, though in the intermediate subgroup concordance was only fair. Using the mean (of three measures of) CFVR for the same comparison improved the agreement in the intermediate subgroup to good (86%, kappa = 0.58, P = 0.002), and in the entire cohort the agreement was very good (88%, kappa = 0.74, P < 0.0001). There was only fair correlation between measures of CFVR and percent coronary stenosis. CFVR improved from 1.8 +/- 0.8 to 2.7 +/- 0.7 after percutaneous intervention (n = 12, P < 0.0

Objectives: Monitoring of brachial blood pressure during exercise-electrocardiogram (ECG) testing is mandatory and changes in blood pressure (BP) can provide critical management evidence. Patient movement, mechanical vibration, artifactual sounds and observer variability make standard manual techniques problematic. This was an investigator-initiated study to assess an automated auscultatory technique of BP assessment [Tango exercise blood pressure monitor (SunTech Medical Instruments, NC, USA)] to adequately measure BP during stress-ECG testing. Method(s): Initially five fit young male volunteers underwent invasive right brachial artery BP recording using a low-compliance fluid-filled catheter with simultaneous manual and automated assessment. Secondarily, during exercise-ECG testing, the system was assessed against beat-to-beat brachial blood pressures obtained from a catheter-tip solid-state pressure manometer positioned in the ipsilateral brachial artery. Result(s): In the supine study overall mean difference (+/- SEM) between invasive and manual blood pressures was 3.26 (1.53) and 3.89 (1.90) mmHg for diastolic BP (DBP) and systolic BP (SBP) respectively. Corresponding differences between invasive and automated results, and manual and automated were 3.68 (0.84) and -7.31 (1.83) mmHg, and -0.64 (+/- 1.43) and -11.42 (+/- 1.59) mmHg. During treadmill exercise-ECG testing the combined mean difference (+/- SEM) between invasive and automated SBP and DBP was 4.79 (+/- 0.14) and 6.33 (+/- 0.10) mmHg, respectively. Conclusion(s): Automated BP assessment during exercise-ECG testing is feasible with the use of appropriate automatic devices likely to be at least as accurate as manual BP registration. The Tango device is tolerant to exercise and provides reliable automatic BP assessment with absolute differences within an acceptable clinical range. © 2004 Lippincott Williams & Wilkins.

Visual and quantitative assessments of percent diameter stenosis on coronary angiography correlate poorly with functional testing, particularly in intermediate-severity (40%-70%) lesions, yet are frequently relied on to make decisions regarding revascularization. Coronary flow velocity reserve (CFVR) and relative CFVR (RCFVR) are promising methods for on-line functional assessment of lesion severity in the catheterization laboratory. We sought to determine the agreement between maximal, mean, and relative CFVR and stress echocardiography in intermediate-severity stenoses. The results of exercise or dobutamine stress echocardiography and CFVR measured by intracoronary Doppler were compared in 28 patients referred for assessment of intermediate-severity stenoses, using 15 patients with either angiographically normal coronary arteries or diameter stenoses > 70% as reference groups. CFVR was measured at least three times in response to a bolus of adenosine in the target vessel distal to the stenosis. RCFVR (target/normal vessel CFVR) was also measured in 27 patients. Maximal, mean (of three measures), and relative CFVR were calculated. CFVR >= 2.0 and RCFVR >= 0.75 were accepted as normal. A minority (29%) of patients in the intermediate-severity stenosis group had a positive test by either method. There was good to very good agreement between stress echocardiography and maximal CFVR (84%, kappa = 0.62, P < 0.0001) and RCFVR (81%, kappa = 0.59, P < 0.001) across the entire patient cohort, though in the intermediate subgroup concordance was only fair. Using the mean (of three measures of) CFVR for the same comparison improved the agreement in the intermediate subgroup to good (86%, kappa = 0.58, P = 0.002), and in the entire cohort the agreement was very good (88%, kappa = 0.74, P < 0.0001). There was only fair correlation between measures of CFVR and percent coronary stenosis. CFVR improved from 1.8 +/- 0.8 to 2.7 +/- 0.7 after percutaneous intervention (n = 12, P < 0.0

Objectives: Monitoring of brachial blood pressure during exercise-electrocardiogram (ECG) testing is mandatory and changes in blood pressure (BP) can provide critical management evidence. Patient movement, mechanical vibration, artifactual sounds and observer variability make standard manual techniques problematic. This was an investigator-initiated study to assess an automated auscultatory technique of BP assessment [Tango exercise blood pressure monitor (SunTech Medical Instruments, NC, USA)] to adequately measure BP during stress-ECG testing. Method(s): Initially five fit young male volunteers underwent invasive right brachial artery BP recording using a low-compliance fluid-filled catheter with simultaneous manual and automated assessment. Secondarily, during exercise-ECG testing, the system was assessed against beat-to-beat brachial blood pressures obtained from a catheter-tip solid-state pressure manometer positioned in the ipsilateral brachial artery. Result(s): In the supine study overall mean difference (+/- SEM) between invasive and manual blood pressures was 3.26 (1.53) and 3.89 (1.90) mmHg for diastolic BP (DBP) and systolic BP (SBP) respectively. Corresponding differences between invasive and automated results, and manual and automated were 3.68 (0.84) and -7.31 (1.83) mmHg, and -0.64 (+/- 1.43) and -11.42 (+/- 1.59) mmHg. During treadmill exercise-ECG testing the combined mean difference (+/- SEM) between invasive and automated SBP and DBP was 4.79 (+/- 0.14) and 6.33 (+/- 0.10) mmHg, respectively. Conclusion(s): Automated BP assessment during exercise-ECG testing is feasible with the use of appropriate automatic devices likely to be at least as accurate as manual BP registration. The Tango device is tolerant to exercise and provides reliable automatic BP assessment with absolute differences within an acceptable clinical range. © 2004 Lippincott Williams & Wilkins.

Background: Electrocardiographic methods still provide the bulk of cardiovascular diagnostics. Cardiac ischemia is associated with typical alterations in cardiac biosignals that have to be measured, analyzed by mathematical algorithms and allegorized for further clinical diagnostics. The fast growing fields of biomedical engineering and applied sciences are intensely focused on generating new approaches to cardiac biosignal analysis for diagnosis and risk stratification in myocardial ischemia.Objectives: To present and review the state of the art in and new approaches to electrocardiologic methods for non-invasive detection and risk stratification in coronary artery disease (CAD) and myocardial ischemia; secondarily, to explore the future perspectives of these methods. Methods: In follow-up to the Expert Discussion at the 2008 Workshop on "Biosignal Analysis" of the German Society of Biomedical Engineering in Potsdam, Germany, we comprehensively searched the pertinent literature and databases and compiled the results into this review. Then, we categorized the state-of-the-art methods and selected new approaches based on their applications in detection and risk stratification of myocardial ischemia. Finally, we compared the pros and cons of the methods and explored their future potentials for cardiology.Results: Resting ECG, particularly suited for detecting ST-elevation myocardial infarctions, and exercise ECG, for the diagnosis of stable CAD, are state-of-the-art methods. New exercise-free methods for detecting stable CAD include cardiogoniometry (CGM); methods for detecting acute coronary syndrome without ST elevation are Body Surface Potential Mapping, functional imaging and CGM. Heart rate variability and blood pressure variability analyses, microvolt T-wave alternans and signal-averaged ECG mainly serve in detecting and stratifying the risk for lethal arrythmias in patients with myocardial ischemia or previous myocardial infarctions. Telemedicine and ambient-as, Hintergrund: Elektrokardiografische Verfahren stellen nach wie vor die primär wichtigsten Methoden zur kardiologischen Diagnostik dar. Eine Herzischämie geht mit typischen Veränderungen kardialer Biosignale einher, die anhand mathematischer Algorithmen analysiert und für den weiteren klinischen Pfad aufbereitet werden müssen. Die rasant wachsende Biomedizintechnik sowie angewandte Wissenschaften beschäftigen sich intensiv mit neuen Ansätzen zur Auswertung kardialer Biosignale zur Ischämiediagnostik und Risikostratifizierung. Ziele: Hauptziel dieser Übersichtsarbeit ist es, den gegenwärtigen Stand der Technik sowie neue Ansätze im Bereich elektrokardiologischer Verfahren zur nicht-invasiven Erkennung und Risikostratifizierung von koronarer Herzkrankheit (KHK) und Myokardischämie vorzustellen und zu bewerten. Als Sekundärziel werden die Zukunftsperspektiven dieser Verfahren aufgezeigt. Methoden: Beginnend mit Expertendiskussionen während des Workshops "Biosignalverarbeitung" der Deutschen Gesellschaft für Biomedizinische Technik (2008 in Potsdam) sowie anschließenden intensiven Recherchen der Literatur und Datenbanken wurde dieser Review erstellt. Es erfolgte eine Kategorisierung von Verfahren des Standes der Technik sowie ausgewählter neuer Ansätze entsprechend ihrer Einsatzgebiete zur Ischämiediagnostik und Risikostratifizierung. Die Vor- und Nachteile wurden aufgezeigt und die künftigen Möglichkeiten dieser Verfahren in der Kardiologie untersucht.Ergebnisse: Als Stand der Technik anzusehen ist das Ruhe-EKG (insbesondere geeignet für Erkennung von ST-Hebungsinfarkten) und das Belastungs-EKG (Diagnostik von stabiler KHK). Neue belastungsfreie Verfahren zur Erkennung von stabiler KHK sind die Kardiogoniometrie (KGM) sowie zur Erkennung des Akuten Koronarsyndroms ohne ST-He bung das Body Surface Potential Mapping, Funktionelle Bildgebung sowie die KGM. Analyse von Herzfrequenz- und Blutdruckvariabilität, T-Wel len-Alterna

Aims Evaluation of angiographical and intracoronary Doppler-derived parameters of coronary stenosis severity. Methods and Results A total of 225 patients with one-vessel disease were studied before PTCA and at 6 months follow-up. Exercise electrocardiography was performed to document presence (n=157) or absence (n=138) of an ST segment shift (greater than or equal to 0.1 mV). Intracoronary blood flow velocity analysis was performed to determine the proximal/distal flow velocity ratio, the distal diastolic/systolic flow velocity ratio and coronary flow velocity reserve. Receiver operator characteristic curves were calculated to assess the predictive value of these variables compared with the exercise test. The distal coronary flow velocity reserve demonstrated the best linear correlation for both percentage diameter stenosis and minimum lumen diameter (r=0.67 and r=0.66; P<0.01), compared to the diastolic/systolic flow velocity ratio (r=0.19 and r=0.14; P<0.01) and the proximal/distal flow velocity ratio (r=0.03 and r=0.07; not significant). The areas under the curve were 0.84 +/- 0.02; 0.82 +/- 0.03 and 0.83 +/- 0.03 for diameter stenosis, minimum lumen diameter and coronary flow velocity reserve, respectively. Logistic regression analysis revealed that the percentage diameter stenosis or minimum lumen diameter and coronary flow velocity reserve were independent predictors for the result of stress testing. Conclusions The distal coronary flow velocity reserve is the best intracoronary Doppler parameter for evaluation of coronary narrowings. Angiographical estimates of coronary lesion severity and distal coronary flow velocity reserve are good and independent predictors for the assessment of functional severity of coronary stenosis, emphasizing the complementary role of these parameters for clinical decision making. (C) 2000 The European Society of Cardiology.

It is unclear whether echocardiography at peak bicycle exercise adds information to registrations obtained recumbent immediately after the test and what factors influence image quality. Therefore, exercise echocardiography was performed consecutively and prospectively in 66 men, unselected with regard to echocardiography, one month after an episode of unstable coronary artery disease. Of 594 segments (9 × 66), 569 (96%) were adequately visualized recumbent at rest. The corresponding figures recumbent directly after exercise, seated before exercise, and seated at peak exercise were 544 (92%), 474 (80%), and 428 (72%), respectively. In the majority of our patients, acceptable images at peak exercise were obtained for the septal region, while for the anterior, lateral, and inferior segments the success rate varied from 50 to 70%. Recumbent after exercise, the success rate was acceptable for most segments, possibly with the exception of the apical and lateral segments. Fifty‐five patients developed new wall motion abnormalities or worsening of wall motion in connection with exercise. Echocardiography at peak exercise provided more information than afterwards in patients with images of good quality. However, in patients with inferior image quality, the registrations obtained recumbent after the test revealed wall motion abnormalities which were not obtained seated at peak exercise. Patients with worse image quality had significantly higher respiratory rate and weight, and rated a higher degree of dyspnoea at peak exercise than those with good quality. We conclude that in middle aged men with coronary artery disease, image acquisition at peak bicycle exercise and immediately after exercise are of complementary value.