American College of Cardiology/American Heart Association Clinical Competence statement on stress testing: a report of the American College of Cardiology/American Heart Association/American College of Physicians--American Society of Internal Medicine Task Force on Clinical Competence

What Mathematical Models Are Accurate for Prescribing Aerobic Exercise in Women with Fibromyalgia?

Simple Summary

Intensity prescription for cardiorespiratory exercises is crucial for achieving health/fitness benefits. However, not all of the population can access a cardiopulmonary exercise test, either for economic reasons or location resources, to determine their ventilatory thresholds. Therefore, different mathematical models can predict the intensity based on the maximum or reserve heart rate. Exercise prescription guidelines indicate that people with fibromyalgia should exercise at 60% of their VO₂max. However, people with fibromyalgia suffer from dysautonomia, which could lead to chronotropic incompetence, the inability to increase heart rate with increasing exercise intensities. Therefore, this study aimed to investigate the relationship and level of agreement between different mathematical models and the heart rate obtained from a cardiopulmonary exercise test at their ventilatory threshold 1. The results showed that the well-known “220 − age” at 76% and the mathematical model designed for people with fibromyalgia “209 − 0.85 × age” at 76% showed a significant level of agreement. However, Tanaka and Karvonen’s formula did not show a significant level of agreement. Thus, the “220 − age” at 76% and “209 − 0.85 × age” at 76% can be used in people with FM to prescribe aerobic exercise.

Abstract

Objectives: This article aims to verify the agreement between the standard method to determine the heart rate achieved in the ventilatory threshold 1 in the cardiopulmonary exercise testing (VT1) and the mathematical models with exercise intensities suggested by the literature in order to check the most precise for fibromyalgia (FM) patients. Methods: Seventeen women with FM were included in this study. The VT1 was used as the standard method to compare four mathematical models applied in the literature to calculate the exercise intensity in FM patients: the well-known “220 − age” at 76%, Tanaka predictive equation “208 − 0.7 × age” at 76%, the FM model HRMax “209 – 0.85 × age” at 76%, and Karvonen Formula at 60%. Bland–Altman analysis and correlation analyses were used to explore agreement and correlation between the standard method and the mathematical models. Results: Significant correlations between the heart rate at the VT1 and the four mathematical estimation models were observed. However, the Bland-Altman analysis only showed agreement between VT1 and “220 − age” (bias = −114.83 + 0.868 × x; 95% LOA = −114.83 + 0.868 × x + 1.96 × 7.46 to −114.83 + 0.868 × x − 1.96 × 7.46, where x is the average between the heart rate obtained in the CPET at VT1 and “220 − age”, in this case 129.15; p = 0.519) and “209 − 0.85 × age”(bias = −129.58 + 1.024 × x; 95% LOA = −129.58 + 1.024 × x + 1.96 × 6.619 to −129.58 + 1.024 × x − 1.96 × 6.619, where x is the average between the heart rate obtained in the CPET at VT1 and “209 − 0.85 × age”, in this case 127.30; p = 0.403). Conclusions: The well-known predictive equation “220 − age” and the FM model HRMax (“209 − 0.85 × age”) showed agreement with the standard method (VT1), revealing that it is a precise model to calculate the exercise intensity in sedentary FM patients. However, proportional bias has been detected in all the mathematical models, with a higher heart rate obtained in CPET than obtained in the mathematical model. The chronotropic incompetence observed in people with FM (inability to increase heart rate with increasing exercise intensities) could explain why methods that tend to underestimate the HRmax in the general population fit better in this population.

Scope of Practice of US Interventional Cardiologists from an Analysis of Medicare Billing Data

The contemporary scope of practice of interventional cardiologists (ICs) in the United States and recent trends are unknown. Using Medicare claims from 2013 to 2017, we categorized ICs into 4 practice categories (only percutaneous coronary intervention [PCI], PCI with noninvasive imaging, PCI with specialized interventions [peripheral/structural], and all 3 services) and evaluated associations with region, hospital bed size and teaching status, gender, and graduation year. Of 6,083 ICs in 2017, 10.9% performed only PCI, 68.3% PCI with noninvasive imaging, 5.7% PCI with specialized interventions, and 15.1% all 3 services. A higher proportion of Northeast ICs (vs South ICs) were performing only PCI (24.8% vs 7.3%) and PCI with specialized interventions (12% vs 3.4%), but lower PCI and noninvasive imaging (53.8% vs 71.7%) and all 3 services (9.3% and 17.6%). Regarding ICs at larger hospitals (bed size >575 vs <218), a higher proportion was performing only PCI (23.8% vs 5.2%) or PCI with specialized interventions (13.5% vs 1.7%) and lower proportion was performing PCI with noninvasive imaging (48.8% vs 78%), similar to teaching hospitals. Female ICs (vs male ICs) more frequently performed only PCI (18.9% vs 10.6%) and less frequently all 3 services (8.3% vs 15.4%). A lower proportion of recent graduates (2001 to 2016) performed only PCI (9.8% vs 13.8%) and PCI with noninvasive imaging (66.3% vs 72.6%) but a higher proportion performed all 3 services (18% vs 8.4%) than earlier graduates (1959 to 1984). From 2013 to 2017, only PCI and PCI with noninvasive imaging decreased, whereas PCI and specialized interventions and all 3 services increased (all p <0.001). In conclusion, there is marked heterogeneity in practice responsibilities among ICs, which has implications for training and competency assessments.

Performance and Interpretation of Office Exercise Stress Testing

In an era where cardiovascular disease continues to increase in prevalence, chest pain is a commonly encountered complaint in the outpatient setting. Clinicians are often tasked with the challenge of selecting the most appropriate screening tool in the evaluation of a patient with suspected coronary artery disease. With proper consideration of indications and contraindications, exercise electrocardiogram (ECG) stress testing is an accessible, cost-conscious, and validated outpatient diagnostic modality for predicting coronary artery disease.

Acute Hemodynamic Effects of Virtual Reality-Based Therapy in Patients of Cardiovascular Rehabilitation: A Cluster Randomized Crossover Trial

OBJECTIVE

To analyze the acute hemodynamic effects of adding virtual reality-based therapy (VRBT) using exergames for patients undergoing cardiac rehabilitation (CR).

DESIGN

Crossover trial.

SETTING

Outpatient rehabilitation center.

PARTICIPANTS

Patients (N=27) with a diagnosis of cardiovascular disease or cardiovascular risk factors. Mean age (years) ± SD was 63.4±12.7 and mean body mass index (kg/m2) ± SD was 29.0±4.0.

INTERVENTIONS

Patients performed 1 VRBT session and 1 CR session on 2 nonconsecutive days. Each session comprised an initial rest, warm-up, conditioning, and recovery. During warm-up, in the VRBT session, games were performed with sensors to reproduce the movements of avatars and, in the CR session, patients were required to reproduce the movements of the physiotherapists. In the conditioning phase for VRBT, games were also played with motion sensors, dumbbells, and shin guards. The CR session consisted of exercises performed on a treadmill. The intensity of training was prescribed by heart rate reserve (HRR; 40%-70%).

MAIN OUTCOME MEASURES

The primary outcomes were heart rate, blood pressure, respiratory rate (RR), rating of perceived exertion (RPE), and peripheral oxygen saturation, evaluated before, during, and after the VRBT or CR session on 2 nonconsecutive days. The secondary outcome was to evaluate whether the patients achieved the prescribed HRR and the percentage of time they maintained this level during the VRBT session.

RESULTS

VRBT produces a physiological similar pattern of acute hemodynamic effects in CR. However, there was greater magnitude of heart rate, RR, and RPE (P<.01) during the execution of VRBT and until 5 minutes of recovery, observed at the moments of rest, and 1, 3, and 5 minutes of recovery.

CONCLUSIONS

Although the VRBT session produces similar physiological acute hemodynamic effects in CR, greater magnitudes of heart rate, RR, and RPE were observed during its execution and up to 5 minutes after the session.

[Exercise testing: New guidelines]

The GERS-P (Exercise Rehabilitation Sports Prevention Group of the French Society of Cardiology) has decided to update current guidelines regarding the practice of EKG stress tests. Since the last update dates from 1997, the GERS judged it necessary to integrate data from new works and advancements made in the last 20 years. Good clinical practices and safety conditions are better defined regarding the structure, location, material, staff competency, as well as convention with hospital structures. The diagnosis of coronary artery disease remains the principal indication for a stress test. Interpretation of the results is crucial - it must be multivariate and provide either a low, intermediate or strong probability of the existence of coronary lesions, taking into account the studied population (risk factors, age, sex and symptoms). We no longer have to talk about a "positive, negative or litigious" test. Several new indications for a stress test have been defined for the assessment of cardiac pathologies. With such indications, the use of gas expiration measurements is highly recommended in order to provide a precise prognosis for all the various cardiac pathologies : congenital, ischemic, valvular, cardiomyopathy, congestive heart failure, rhythm and conduction disorders, pacemaker fine-tuning, or pulmonary hypertension. Indications for stress tests and contraindications are defined according to different population subgroups, for instance : athletes, women, children, the elderly, asymptomatic patients, diabetics, hypertensive patients, peripheral arteritis disease patients, or in the context of a non-cardiac surgery pre-op visit. The new guidelines are considerably different from those dating from 1997 and further pinpoint the relevance and importance of an EKG stress test within the arsenal of complementary cardiologic exams. With the improvements made in providing diagnostic value in CAD, as well as better prognostic value for any underlying pathology, the indication for an EKG stress test has extended to all cardiovascular disease.

Assessment of oxygen-uptake efficiency slope in healthy children and children with heart disease: Generation of appropriate reference values for the OUES variable

Background

Oxygen-uptake efficiency slope (OUES) is an objective measure of functional capacity that does not require a maximal effort but is considerably dependent on anthropometric variables and requires the generation of an appropriate reference value in children. This study aimed to establish normal reference values for OUES/kg in children with and without congenital heart diseases. Besides that, reference values are presented secondarily for OUES per body surface area (OUES/BSA).

Design

Cross-sectional.

Methods

Six hundred and seventy-six children and adolescents performed a maximal cardiopulmonary exercise test (305 healthy controls and 371 individuals with congenital heart defect), between four and 21 years old (481 males and 195 females, with a mean age of 12 years).

Results

The OUES reference value for the classification of children and adolescents with normal functional capacity (>80% of predicted maximum oxygen uptake) was 34.63 (sensitivity 77% and specificity 83%, p < 0.05). Regarding the body surface area, considering healthy patients and those with heart disease, the cutoff value of the OUES/BSA was 1151 with sensitivity of 79% and specificity of 79%.

Conclusions

OUES/kg may be an important marker tool in the differentiation between preserved or abnormal functional capacity in children and adolescents with and without congenital heart disease, even at the submaximal level of exercise.

Quality control of regional wall motion analysis in stress Echo 2020

BACKGROUND

The trial "Stress Echo (SE) 2020" evaluates novel applications of SE beyond coronary artery disease. The aim of the study was control quality and harmonize reading criteria.

METHODS

One reader from 78 centers of the SE 2020 network asked for credentials to read a set of 20 SE video-clips selected by the core lab. All aspiring centers met the pre-requisite of high-volume and the years of experience in SE ranged from 5 to 31years (mean value 18years). The diagnostic gold standard was a reading by the core lab. The a priori determined pass threshold was 18/20 (≥90%).

RESULTS

Of the initial 78 who started, 57 completed the first attempt: individual readers' score on first attempt ranged from 07/20 to 20/20 (accuracy from 35% to 100%, mean 78.7±13%) and 44 readers passed it. There was a very poor correlation between years of experience and the reader's score on first attempt (r=-0.161, p=0.231). Of the 13 readers who failed the first attempt, 12 took it again after the web-based session and their accuracy improved (74% vs. 96%, p<0.001). The kappa inter-observer agreement before and after web-based training was 0.59 on first attempt and rose to 0.91 on the last attempt.

CONCLUSIONS

In SE reading, the volume of activity or years of experience is not synonymous with diagnostic quality. Qualitative analysis and operator-dependence can become a limiting weakness in clinical practice, in the absence of strict pathways of learning, credentialing and audit.

[Exercise testing: New guidelines]

The GERS (Exercise Rehabilitation and Sports Group of the French Society of Cardiology) has decided to update current guidelines regarding the practice of EKG stress tests. Since the last update dates from 1997, the GERS judged it necessary to integrate data from new works and advancements made in the last 20 years. Good clinical practices and safety conditions are better defined regarding the structure, location, material, staff competency, as well as convention with hospital structures. The diagnosis of coronary artery disease remains the principal indication for a stress test. Interpretation of the results is crucial-it must be multivariate and provide either a low, intermediate or strong probability of the existence of coronary lesions, taking into account the studied population (risk factors, age, sex and symptoms). Several new indications for a stress test have been defined for the assessment of cardiac pathologies. With such indications, the use of gas expiration measurements is highly recommended in order to provide a precise prognosis for all the various cardiac pathologies : congenital, ischemic, valvular, cardiomyopathies, congestive heart failure, rhythm and conduction disorders, pacemaker fine-tuning, or pulmonary hypertension. Indications for stress tests and contraindications are defined according to different population subgroups, for instance : athletes, women, children, the elderly, asymptomatic patients, diabetics, hypertensive patients, PAD patients, or in the context of a non-cardiac surgery pre-op visit. The new guidelines (due for publication soon) are considerably different from those dating from 1997 and further pinpoint the relevance and importance of an EKG stress test within the arsenal of complementary cardiologic exams. With the improvements made in providing diagnostic value in CAD, as well as better prognostic value for any underlying pathology, the indication for an EKG stress test has extended to all cardiovascular disease.

Two Models to Conduct Nonphysician-led Exercise Stress Testing in Low to Intermediate Risk Patients

BACKGROUND

Exercise stress testing (EST) is a noninvasive procedure that aids the diagnosis and prognosis of a range of cardiac pathologies. Reduced access is recognized as a limiting factor in enabling early access to treatment or safe and appropriate discharge. Increased accessibility can be achieved by utilizing nonphysician health practitioners to supervise tests. To implement nonphysician-led EST in clinical environments, there is a need for the development and administration of feasible and effective models.

OBJECTIVE

Via inpatient and outpatient referral, this article aims to present 2 standardized models of care for patients requiring EST for diagnostic and prognostic evaluation of numerous pathologies.

METHOD

An inpatient and outpatient model was implemented at the Royal Brisbane and Women's Hospital and Logan Hospital in Queensland, Australia between July 2013 and December 2015. Tests were performed by 2 cardiac scientists employed by each hospital. All tests were immediately reported by a cardiology advanced trainee registrar or consultant cardiologist.

RESULTS

A total of 2095 tests were performed via the 2 models. Overall, 73 had a positive result (3.5%), 120 equivocal (5.7%), 129 inconclusive/submaximal (6.2%), and 1773 negative (85.2%). After further testing, 38 of the patients with positive and equivocal results were diagnosed with flow-limiting coronary artery disease. The remaining patients were resolved as negative through further diagnostic testing or lost to follow up.

CONCLUSIONS

After implementation of the 2 models, patient flow was improved for earlier discharge, reduced waiting times, or timely identification of possible cardiac pathologies, thereby optimizing patient care.

Cost-effectiveness of diagnostic evaluation strategies for individuals with stable chest pain syndrome and suspected coronary artery disease

PURPOSE

To determine lifetime cost-effectiveness of diagnostic evaluation strategies for individuals with stable chest pain and suspected coronary artery disease (CAD).

METHODS

Exercise treadmill testing (ETT), stress echocardiography (SE), myocardial perfusion scintigraphy (MPS), coronary computed tomographic angiography (CCTA), and invasive coronary angiography (ICA) were assessed alone, or in succession to each other.

RESULTS

Initial ETT followed by imaging wherein ETT was equivocal or unable to be performed appeared more cost-effective than any strategy employing initial testing by imaging.

CONCLUSION

As pre-test likelihood of CAD varies, different modalities including SE, CCTA, and MPS result in improved costs and enhanced effectiveness.

The early identification of psychosis: can lessons be learnt from cardiac stress testing?

Psychotic disorders including schizophrenia are amongst the most debilitating psychiatric disorders. There is an urgent need to develop methods to identify individuals at risk with greater precision and as early as possible. At present, a prerequisite for a diagnosis of schizophrenia is the occurrence of a psychotic episode. Therefore, attempting to detect schizophrenia on the basis of psychosis is analogous to diagnosing coronary artery disease (CAD) after the occurrence of a myocardial infarction (MI). The introduction of cardiac stress testing (CST) has revolutionized the detection of CAD and the prevention and management of angina and MI. In this paper, we attempt to apply lessons learnt from CST to the early detection of psychosis by proposing the development of an analogous psychosis stress test. We discuss in detail the various parameters of a proposed psychosis stress test including the choice of a suitable psychological or psychopharmacological "stressor," target population, outcome measures, safety of the approach, and the necessary evolution of test to become clinically informative. The history of evolution of CST may guide the development of a similar approach for the detection and management of psychotic disorders. The initial development of a test to unmask latent risk for schizophrenia will require the selection of a suitable and safe stimulus and the development of outcome measures as a prelude to testing in populations with a range of risk to determine predictive value. The use of CST in CAD offers the intriguing possibility that a similar approach may be applied to the detection and management of schizophrenia.

Safety and feasibility of dobutamine stress cardiac magnetic resonance for cardiovascular assessment prior to renal transplantation

AIMS

Current guidelines recommend cardiovascular risk assessment prior to renal transplantation. There is currently no evidence for the role of cardiovascular magnetic resonance (CMR) in this population, despite an established evidence base in the non-chronic kidney disease (CKD) population. Our aim is to determine the feasibility and safety of dobutamine stress CMR (DSCMR) imaging in the risk stratification of CKD patients awaiting renal transplantation.

METHODS

CKD patients who were deemed at high risk for coronary artery disease (CAD) and awaiting renal transplantation underwent DSCMR.

RESULTS

Forty-one patients whose median age was 56 years (range 28–73 years) underwent DSCMR. Nineteen were undergoing haemodialysis, 10 peritoneal dialysis and 12 pre-dialysis. The aetiology of the renal failure was diabetes mellitus in 29%, glomerulonephritis in 24%, hypertension in 22% and autosomal dominant polycystic kidney disease in 10%. Thirty-eight patients (93%) achieved the end point, either positive for ischaemia or negative, achieving at least 85% of age-predicted heart rate. Two of them did not achieve target heart rate and one was discontinued because of severe headache. Of the 38 patients who achieved the end point, 35 (92%) were negative for inducible wall motion abnormalities and four (10%) were positive. There were no serious adverse effects.

CONCLUSION

DSCMR is a well tolerated and viable investigation for the cardiovascular risk stratification of high-risk CKD patients prior to renal transplantation. DSCMR already has an established evidence base in the non-CKD population with superiority over other noninvasive techniques. Larger studies with outcome data are now required to define its true utility in the CKD population.

Non-physician-led exercise stress testing is a safe and effective practice

Exercise stress testing is a non-invasive procedure that provides diagnostic and prognostic information for the evaluation of several pathologies, including arrhythmia provocation, assessment of exercise capacity, and coronary heart disease. Historically, exercise tests were directly supervised by physicians; however, cost-containment issues and time constraints on physicians have encouraged the use of health professionals with specific training and experience to supervise selected exercise stress tests. Evidence suggests that non-physician-led exercise stress testing is a safe and effective practice with similar morbidity and mortality rates as those performed or supervised by a physician.

Evidence-based risk recommendations for best practices in the training of qualified exercise professionals working with clinical populations

This systematic review examines critically "best practices" in the training of qualified exercise professionals. Particular attention is given to the core competencies and educational requirements needed for working with clinical populations. Relevant information was obtained by a systematic search of 6 electronic databases, cross-referencing, and through the authors' knowledge of the area. The level and grade of the available evidence was established. A total of 52 articles relating to best practices and (or) core competencies in clinical exercise physiology met our eligibility criteria. Overall, current literature supports the need for qualified exercise professionals to possess advanced certification and education in the exercise sciences, particularly when dealing with "at-risk" populations. Current literature also substantiates the safety and effectiveness of exercise physiologist supervised stress testing and training in clinical populations.

Stress echo applications beyond coronary artery disease

Stress echocardiography is an established method for the diagnosis and prognostic stratification of coronary artery disease. In the last few years, the tremendous technological and conceptual versatility of this technique has been increasingly applied in challenging diagnostic fields. Today, in the echocardiography laboratory we can detect not only ischaemia from coronary artery stenosis, but can also recognize abnormalities of the coronary microvessels, myocardium, heart valves, pulmonary circulation, alveolar-capillary barrier, and right ventricle. Therefore, we evaluate coronary arteries as well as coronary microvascular disease (associated with diabetes and hypertension), suspected or overt dilated cardiomyopathy, systolic and diastolic heart failure, hypertrophic cardiomyopathy, athletes' hearts, valvular heart disease, congenital heart disease, incipient or overt pulmonary hypertension, and heart transplant patients for early detection of chronic or acute rejection as well as potential donors for better selection of suitable donor hearts. From a stress echo era with a one-fits-all approach (wall motion by 2D-echo in the patient with known or suspected coronary artery disease) now we have moved on to an omnivorous, next-generation laboratory employing a variety of technologies (from M-Mode to 2D and pulsed, continuous and colour Doppler, to lung ultrasound and real-time 3D echo, 2D speckle tracking and myocardial contrast echo) on patients covering the entire spectrum of severity (from elite athletes to patients with end-stage heart failure) and ages (from children with congenital heart disease to the elderly with low-flow, low-gradient aortic stenosis). For each patient, we can tailor a dedicated stress protocol with a specific method to address a particular diagnostic question. Provided that the acoustic window is acceptable and the necessary expertise available, stress echocardiography is useful and convenient in many situations, from valvular to congenital heart disease, and whenever there is a mismatch between symptoms during stress and findings at rest. Increasing societal concern regarding cost, environment and radiation risks of medical imaging will lead to a preferential application of ultrasound over competing techniques, due to its unsurpassed versatility, portability, absence of radiation, and low cost.

Comparison of treadmill exercise stress cardiac MRI to stress echocardiography in healthy volunteers for adequacy of left ventricular endocardial wall visualization: A pilot study

PURPOSE

To compare exercise stress cardiac magnetic resonance (cardiac MR) to echocardiography in healthy volunteers with respect to adequacy of endocardial visualization and confidence of stress study interpretation.

MATERIALS AND METHODS

Twenty-eight healthy volunteers (age 28 ± 11 years, 15 males) underwent exercise stress echo and cardiac MR one week apart assigned randomly to one test first. Stress cardiac MR was performed using an MRI-compatible treadmill; stress echo was performed as per routine protocol. Cardiac MR and echo images were independently reviewed and scored for adequacy of endocardial visualization and confidence in interpretation of the stress study.

RESULTS

Heart rate at the time of imaging was similar between the studies. Average time from cessation of exercise to start of imaging (21 vs. 31 s, P < 0.001) and time to acquire stress images (20 vs. 51 s, P < 0.001) was shorter for cardiac MR. The number of myocardial segments adequately visualized was significantly higher by cardiac MR at rest (99.8% vs. 96.4%, P = 0.002) and stress (99.8% vs. 94.1%, P = 0.001). The proportion of subjects in whom there was high confidence in the interpretation was higher for cardiac MR than echo (96% vs. 60%, P = 0.005).

CONCLUSION

Exercise stress cardiac MR to assess peak exercise wall motion is feasible and can be performed at least as rapidly as stress echo.

Exercise-induced bronchoconstriction in elite long-distance runners in Brazil

OBJECTIVE

To determine the prevalence of exercise-induced bronchoconstriction among elite long-distance runners in Brazil and whether there is a difference in the training loads among athletes with and without exercise-induced bronchoconstriction.

METHODS

This was a cross-sectional study involving elite long-distance runners with neither current asthma symptoms nor a diagnosis of exercise-induced bronchoconstriction. All of the participants underwent eucapnic voluntary hyperpnea challenge and maximal cardiopulmonary exercise tests, as well as completing questionnaires regarding asthma symptoms and physical activity, in order to monitor their weekly training load.

RESULTS

Among the 86 male athletes recruited, participation in the study was agreed to by 20, of whom 5 (25%) were subsequently diagnosed with exercise-induced bronchoconstriction. There were no differences between the athletes with and without exercise-induced bronchoconstriction regarding anthropometric characteristics, peak oxygen consumption, baseline pulmonary function values, or reported asthma symptoms. The weekly training load was significantly lower among those with exercise-induced bronchoconstriction than among those without.

CONCLUSIONS

In this sample of long-distance runners in Brazil, the prevalence of exercise-induced bronchoconstriction was high.

GRACE and TIMI risk scores but not stress imaging predict long-term cardiovascular follow-up in patients with chest pain after a rule-out protocol

Objective

To determine the long-term prognostic value of stress imaging and clinical risk scoring for cardiovascular mortality in chest pain patients after ruling out acute coronary syndrome (ACS).

Methods

A standard rule-out protocol was performed in emergency room patients with a normal or non-diagnostic admission electrocardiogram (ECG) within 6 h of chest pain onset. ACS patients were identified by troponin T, recurrent angina and serial ECG. Dobutamine stress echocardiography (DSE) was performed after ACS was ruled out. Myocardial perfusion scintigraphy (MPS) was performed within 6 months in an outpatient setting according to the physician’s discretion.

Results

524 patients were included. GRACE and TIMI risk scores were 75 (57–96) and 1 (0–2) in the rule-out ACS group, and 89 (74–107) and 2 (1–3) in the ACS group, respectively (median, interquartile range). Follow-up (median 9.4 (8.9–10.0) years) was complete in 96%. 350 of 379 rule-out ACS patients had an interpretable DSE and 52 patients underwent an MPS. 21 of the rule-out ACS patients (6%) died of a cardiovascular cause compared with 24 (17%) ACS patients (p < 0.001). For rule-out ACS patients, C-statistics were 0.829 and 0.803 for the GRACE and TIMI scores. In these patients, DSE and MPS outcome did not predict long-term cardiovascular mortality. In multivariate analysis, known chronic heart failure, ACE inhibitor use, and GRACE score were independent predictors of cardiovascular mortality.

Conclusions

TIMI and GRACE score but not DSE and MPS are accurate predictors of long-term cardiovascular mortality, even in chest pain patients with a normal or non-diagnostic electrocardiogram undergoing a rule-out protocol.

Ambulatory cardiac single-photon emission computed tomography at the primary care physician's office: a descriptive study

Ambulatory cardiac single-photon emission computed tomography stress testing for the evaluation of coronary artery disease at the primary care physician's office is increasingly utilized without data supporting its safety. In this 2-year prospective pilot study of 1266 consecutive stress-myocardial perfusion imaging studies done in the primary care physician's office using a mobile nuclear cardiology laboratory, adverse events were mild and rare. There were no recorded events of myocardial infarction, serious arrhythmias, severe bronchospasm, hospitalization, or death. This suggests that this practice is safe in this population with these providers. This finding may not apply to a higher-risk population. Further evaluation of referral appropriateness and long-term prognostic value is needed.

The Clinical Significance of Aerobic Exercise Testing and Prescription: From Apparently Healthy to Confirmed Cardiovascular Disease

Aerobic exercise testing clearly provides valuable clinical information in apparently healthy adults as well as a number of patient populations. Maximal aerobic capacity, either estimated from workload or measured directly, is perhaps the most frequently analyzed variable ascertained from such testing. This practice is warranted given the consistent prognostic significance of maximal aerobic capacity. Other variables obtained from the aerobic exercise test, such as the heart rate response during exercise and into recovery, the systolic and diastolic blood pressure responses during exercise, oxygen consumption at anaerobic threshold, and the ventilatory response to exercise, also provide important insight into an individual's health and prognosis. Furthermore, the aerobic exercise test is highly valuable in developing an individualized and safe exercise prescription. Aerobic exercise training goals, with respect to frequency, duration, frequency, and mode of exercise, are well established for the apparently healthy population as well as individuals at risk for or diagnosed with cardiovascular disease. Adherence to these physical activity recommendations clearly provides numerous health benefits, perhaps most important of which is a significant decrease in the risk for cardiovascular events and mortality. This review addresses concepts of aerobic exercise testing and training and discusses their clinical implications.

A gatekeeper for the gatekeeper: inappropriate referrals to stress echocardiography

BACKGROUND

Cardiac imaging stress tests have increased nearly 3-fold in the last decade, with >10 million a year performed in the United States alone. Inappropriate selection for testing may have important consequences because small individual costs (and risks) multiplied by millions of examinations represent a significant societal burden. The aim of this study was to assess the appropriateness of selection for stress echocardiography in 2 high-volume laboratories.

METHODS

This audit of 350 consecutive stress echocardiograms for evaluation of known or suspected coronary artery disease was performed from May to June 2006 at centers in Australia and Italy. Appropriateness was independently scored by a senior clinical cardiologist as follows: I = definitely appropriate, IIa = probably appropriate, IIb = probably inappropriate, or III = definitely inappropriate, based on current guidelines for cardiac stress testing. All referrals were accepted at one center, and referrals were prescreened by cardiology fellows working at the other.

RESULTS

Examinations were definitely appropriate in 217 (62%), probably appropriate in 35 (10%), probably inappropriate in 76 (22%), and definitely inappropriate in 22 (6%) patients. The main reasons of inappropriateness were (1) performance as first-line test (37% of inappropriate tests) and (2) test repeated too often in the absence of change in clinical status (30%). The inappropriate testing rate was higher when no screening of external referral was implemented (43% vs 13%, P < .0001).

CONCLUSIONS

Inappropriate indications for stress echocardiography are common but avoidable if referrals are screened. Targeting inappropriateness opens a unique opportunity to cut health care expenditure with no reduction, and possibly improvement, in health care standards.

The predictive value of cardiorespiratory fitness combined with coronary risk evaluation and the risk of cardiovascular and all-cause death

BACKGROUND

There are no data on directly measured cardiorespiratory fitness combined coronary risk evaluation with respect to death from cardiovascular diseases and all-causes. We investigated the prognostic significance of risk scores and cardiorespiratory fitness with respect to cardiovascular disease and all-cause mortality.

METHODS

Cardiorespiratory fitness (maximal oxygen uptake, VO2peak) was measured by exercise test with an electrically braked cycle ergometer. The study is based on a random population-based sample of 1639 men (42-60 years) without history of type 2 diabetes or atherosclerotic cardiovascular diseases.

RESULTS

During an average follow-up of 16 years, a total of 304 deaths occurred. Independent predictors for all-cause death were European Score (for 1% increment, RR 1.15, 95% CI 1.10-1.20), VO2peak (for 1 MET increment, RR 0.84, 95% CI 0.78-0.89), when adjusted for C-reactive protein, alcohol consumption, serum high-density lipoprotein, waist-to-hip ratio, family history of coronary heart disease, exercise-induced ST changes and the use of medications for hypertension, dyslipidaemia or aspirin. Also, Framingham risk score was related to the risk of death (RR 1.05, 95% CI 1.03-1.07, P < 0.001). Subjects with high European or Framingham score and low VO2peak represent the highest risk group.

CONCLUSION

An important finding is that the risk scores can be used to identify men for whom low cardiorespiratory fitness predicts an especially high risk for death from cardiovascular and any other cause.

Intra-operative myocardial ischaemia cannot be detected by analysis of transmitral inflow patterns in patients undergoing off-pump coronary surgery

BACKGROUND AND OBJECTIVE

Transmitral inflow patterns have been used for detection of myocardial ischaemia. However, its diagnostic value has not been tested in anaesthetized and mechanically ventilated patients undergoing coronary artery bypass graft surgery.

METHODS

Transmitral inflow patterns were studied by transoesophageal Doppler echocardiography in 43 patients undergoing coronary artery bypass graft surgery without cardiopulmonary bypass after opening of the sternum (baseline) and during grafting of the left anterior descending artery. Peak early (E) and peak late (A) transmitral velocities and their ratio (E/A) were recorded. Myocardial ischaemia was defined by standard criteria using two-dimensional echocardiography and seven-lead electrocardiogram.

RESULTS

Thirty-one patients (64 +/- 8 yr, 9 women) fulfilled the predefined inclusion criteria for analysis. During distal revascularization, 16 patients showed myocardial ischaemia and 15 did not. The use of vasoactive drugs, haemodynamic findings and transmitral inflow patterns were similar in both groups at baseline and during grafting. In the ischaemic group, E was 67.1 +/- 13.9 cm s-1 at baseline and 69.5 +/- 23.2 cm s-1 during grafting, and the E/A ratios were 1.3 +/- 0.3 and 1.4 +/- 0.9, respectively. In the non-ischaemic group, E was 64.0 +/- 17.1 cm s-1 at baseline and 60.9 +/- 14.8 cm s-1 during grafting, and the E/A ratios were 1.4 +/- 0.7 and 1.2 +/- 0.3, respectively.

CONCLUSIONS

Analysis of Doppler findings of transmitral inflow patterns did not allow for detection of myocardial ischaemia during surgical revascularization of the myocardium.

Achieving Quality in Cardiovascular Imaging

Cardiovascular imaging has enjoyed both rapid technological advances and sustained growth, yet less attention has been focused on quality than in other areas of cardiovascular medicine. To address this deficit, representatives from cardiovascular imaging societies, private payers, government agencies, the medical imaging industry, and experts in quality measurement met, and this report provides an overview of the discussions. A consensus definition of quality in imaging and a convergence of opinion on quality measures across imaging modalities was achieved and are intended to be the start of a process culminating in the development, dissemination, and adoption of quality measures for all cardiovascular imaging modalities.

Clinical Stress Testing in the Pediatric Age Group

This statement is an updated report of the American Heart Association’s previous publications on exercise in children. In this statement, exercise laboratory requirements for environment, equipment, staffing, and procedures are presented. Indications and contraindications to stress testing are discussed, as are types of testing protocols and the use of pharmacological stress protocols. Current stress laboratory practices are reviewed on the basis of a survey of pediatric cardiology training programs.

Current practice of exercise stress testing among pediatric cardiology and pulmonology centers in the United States

The objective of this study was to characterize current practice patterns for clinical exercise stress testing (EST) in children in the United States. We conducted a survey of 109 pediatric cardiology programs and 91 pediatric pulmonology programs at children's hospitals or university hospitals in the United States. A total of 115 programs from 88 hospitals responded (response rate, 58%). A higher percentage of cardiology programs (98.7%) have exercise laboratories compared with pulmonology programs (77.5%). Sixty-three percent of respondents have both a treadmill and a cycle ergometer. A larger proportion of respondents (76%) rely primarily or exclusively on treadmill, whereas a smaller number use cycle ergometer (24%). Sixty-seven percent of respondents reported that they include metabolic measurements in EST protocols. Respondents have varying minimum age criteria for EST, with 9% reporting < or = 4 years, 25% reporting 5 years, 31% reporting 6 years, 16% reporting 7 years, and 20% reporting > or =8 years. Programs using cycle ergometers tend to test children at a younger age and to measure metabolic parameters. Seventy-nine percent of respondents use Bruce and modified Bruce protocols. Institutional protocols are used by 14%. Ninety percent of respondents use technicians to perform EST and 8% use nurses, but 76% require physician presence during testing. The majority of respondents (57%) perform < 100 pediatric tests per year. There are wide variations in the current practice of EST among pediatric subspecialty programs in the United States. Treadmills are used more frequently than cycle ergometers, and Bruce and modified Bruce protocols are commonly used. Most survey respondents measure metabolic parameters during EST.

EANM/ESC procedural guidelines for myocardial perfusion imaging in nuclear cardiology

The European procedural guidelines for radionuclide imaging of myocardial perfusion and viability are presented in 13 sections covering patient information, radiopharmaceuticals, injected activities and dosimetry, stress tests, imaging protocols and acquisition, quality control and reconstruction methods, gated studies and attenuation-scatter compensation, data analysis, reports and image display, and positron emission tomography. If the specific recommendations given could not be based on evidence from original, scientific studies, we tried to express this state-of-art. The guidelines are designed to assist in the practice of performing, interpreting and reporting myocardial perfusion SPET. The guidelines do not discuss clinical indications, benefits or drawbacks of radionuclide myocardial imaging compared to non-nuclear techniques, nor do they cover cost benefit or cost effectiveness.

Complications during pharmacological stress echocardiography: a video-case series

BACKGROUND

Stress echocardiography is a cost-effective tool for the modern noninvasive diagnosis of coronary artery disease. Several physical and pharmacological stresses are used in combination with echocardiographic imaging, usually exercise, dobutamine and dipyridamole. The safety of a stress is (or should be) a major determinant in the choice of testing. Although large scale single center experiences and multicenter trial information are available for both dobutamine and dipyridamole stress echo testing, complications or side effects still can occur even in the most experienced laboratories with the most skilled operators.

CASE PRESENTATION

We decided to present a case collection of severe complications during pharmacological stress echo testing, including a ventricular tachycardia, cardiogenic shock, transient ischemic attack, torsade de pointe, fatal ventricular fibrillation, and free wall rupture.

CONCLUSION

We believe that, in this field, every past complication described is a future complication avoided; what happens in your lab is more true of what you read in journals; and Good Clinical Practice is not "not having complications", but to describe the complications you had.

Prognostic value of predischarge dobutamine stress echocardiography in chest pain patients with a negative cardiac troponin T

OBJECTIVES

We prospectively studied the prognostic value of predischarge dobutamine stress echocardiography (DSE) in low-risk chest pain patients with a normal or nondiagnostic electrocardiogram (ECG) and a negative serial troponin T.

BACKGROUND

Noninvasive stress testing is recommended before discharge or within 72 h in patients with low-risk chest pain. The prognostic value of immediate DSE has not been studied in a blinded, prospective fashion.

METHODS

Patients presenting at the emergency room within 6 h of symptom onset and a normal or nondiagnostic ECG were eligible. Dobutamine stress echocardiography was performed after unstable coronary artery disease was ruled out by a standard rule-out protocol and a negative serial troponin T; the occurrence of any new wall motion abnormality was considered positive. Results were kept blinded. End points were cardiac death, myocardial infarction, rehospitalization for unstable angina or revascularization.

RESULTS

In total, 377 patients were included. There were 2 deaths, 2 myocardial infarctions, 8 rehospitalization for unstable angina, and 10 revascularizations at six-month follow-up. The end points occurred in 8/26 (30.8%) patients with a positive versus 14/351 (4.0%) patients with a negative DSE (odds ratio, 10.7; 95% confidence interval, 4.0 to 28.8; p < 0.0001). By multivariate analysis, DSE remained a predictor of end points (p < 0.0001).

CONCLUSIONS

A predischarge DSE had important, independent prognostic value in low-risk, troponin negative, chest pain patients.