International Impact of COVID-19 on the Diagnosis of Heart Disease

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic has adversely affected diagnosis and treatment of noncommunicable diseases. Its effects on delivery of diagnostic care for cardiovascular disease, which remains the leading cause of death worldwide, have not been quantified.

OBJECTIVES

The study sought to assess COVID-19's impact on global cardiovascular diagnostic procedural volumes and safety practices.

METHODS

The International Atomic Energy Agency conducted a worldwide survey assessing alterations in cardiovascular procedure volumes and safety practices resulting from COVID-19. Noninvasive and invasive cardiac testing volumes were obtained from participating sites for March and April 2020 and compared with those from March 2019. Availability of personal protective equipment and pandemic-related testing practice changes were ascertained.

RESULTS

Surveys were submitted from 909 inpatient and outpatient centers performing cardiac diagnostic procedures, in 108 countries. Procedure volumes decreased 42% from March 2019 to March 2020, and 64% from March 2019 to April 2020. Transthoracic echocardiography decreased by 59%, transesophageal echocardiography 76%, and stress tests 78%, which varied between stress modalities. Coronary angiography (invasive or computed tomography) decreased 55% (p < 0.001 for each procedure). In multivariable regression, significantly greater reduction in procedures occurred for centers in countries with lower gross domestic product. Location in a low-income and lower-middle-income country was associated with an additional 22% reduction in cardiac procedures and less availability of personal protective equipment and telehealth.

CONCLUSIONS

COVID-19 was associated with a significant and abrupt reduction in cardiovascular diagnostic testing across the globe, especially affecting the world's economically challenged. Further study of cardiovascular outcomes and COVID-19-related changes in care delivery is warranted.

Accelerated magnetic resonance imaging tissue phase mapping of the rat myocardium using compressed sensing with iterative soft-thresholding

Introduction

Tissue Phase Mapping (TPM) MRI can accurately measure regional myocardial velocities and strain. The lengthy data acquisition, however, renders TPM prone to errors due to variations in physiological parameters, and reduces data yield and experimental throughput. The purpose of the present study is to examine the quality of functional measures (velocity and strain) obtained by highly undersampled TPM data using compressed sensing reconstruction in infarcted and non-infarcted rat hearts.

Methods

Three fully sampled left-ventricular short-axis TPM slices were acquired from 5 non-infarcted rat hearts and 12 infarcted rat hearts in vivo. The datasets were used to generate retrospectively (simulated) undersampled TPM datasets, with undersampling factors of 2, 4, 8 and 16. Myocardial velocities and circumferential strain were calculated from all datasets. The error introduced from undersampling was then measured and compared to the fully sampled data in order to validate the method. Finally, prospectively undersampled data were acquired and compared to the fully sampled datasets.

Results

Bland Altman analysis of the retrospectively undersampled and fully sampled data revealed narrow limits of agreement and little bias (global radial velocity: median bias = -0.01 cm/s, 95% limits of agreement = [-0.16, 0.20] cm/s, global circumferential strain: median bias = -0.01%strain, 95% limits of agreement = [-0.43, 0.51] %strain, all for 4x undersampled data at the mid-ventricular level). The prospectively undersampled TPM datasets successfully demonstrated the feasibility of method implementation.

Conclusion

Through compressed sensing reconstruction, highly undersampled TPM data can be used to accurately measure the velocity and strain of the infarcted and non-infarcted rat myocardium in vivo, thereby increasing experimental throughput and simultaneously reducing error introduced by physiological variations over time.

[New Technologies in coronary interventional cardiology: results from the first inter-regional survey promoted by SICI-GISE in four regions of northern Italy ("the GISE TOLOVE" area: Tuscany, Lombardy, Veneto, Emilia-Romagna)]

BACKGROUND

The implementation of the latest medical innovations can vary widely within the same geographic area. This study aimed to describe the current status of recent innovations in the field of coronary interventional cardiology in 4 regions of Northern Italy.

METHODS

From April to May 2014, 4 regional delegations of the Italian Society of Invasive Cardiology (SICI-GISE) have promoted a multicenter survey. By means of a web-based methodology, a focused questionnaire was administered to head physicians of 97 cath-labs in 4 Italian regions within the "GISE TOLOVE" area (Lombardy, Veneto, Tuscany, Emilia-Romagna).

RESULTS

Pharmacological and technological innovations in coronary interventional cardiology appear to be widely used in the area covered by this survey, with uniformity in application and availability of therapeutic devices and drugs within the 4 regions involved. The main limiting factors to the adoption of new technologies and drugs were economic factors or lack of scientific evidence for some specific devices or drugs.

CONCLUSIONS

This survey showed widespread and consistent application of the main latest innovations in coronary interventional cardiology across 4 Italian regions of Northern Italy.

[The use of novel technologies for assessment of myocardial function in clinical practice]

Key factors defining the prognosis of patients with heart failure (HF) are cardiac remodeling and myocardial contractility. New methods of visualization of myocardial motion gave impulse to research in the area of heart physiology and pathology. However in clinical practice these methods are still rarely used. Evaluation of systolic and diastolic functions based on tissue Doppler (TD), 2D and 3D speckle tracking data provides information on the pressure of left ventricular (LV) filling and enables carrying out differential diagnosis between constrictive pericarditis and myocardial diseases with diastolic dysfunction, dyspnea caused by cardiac and extracardiac causes. It also helps to understand physiology of systolic and diastolic dysfunction, impairment of LV pump function. It also enables monitoring response to HF treatment. Myocardial function analysis gives an opportunity to carry out early diagnostics, to detect subclinical LV dysfunction, to detect dyssynchrony and to predict response to resynchronising therapy. In this article we sum up indicators of systolic and diastolic dysfunction in various types of pathology and present assessment of mechanical dyssynchrony with the aid of TD, 2D and 3D speckle tracking. It is stressed that these methods allow carrying out quantitative analysis of myocardial motion. Practically all analyzed parameters are nonspecific and similar to parameters of remodeling change unidirectionally irrespective of pathology. The aim of this article is to summarize available data and knowledge on the determination of myocardial function. This is important for clinical practice and understanding of future development of the above methods.

How prevalent and costly are Choosing Wisely low-value services? Evidence from Medicare beneficiaries

(1) Through the Choosing Wisely initiative, medical specialty societies identified non-indicated cardiac testing in low-risk patients and short-interval dual-energy X-ray absorptiometry (DXA) or bone density testing as low-value care. (2) Nationally, 13 percent of low-risk Medicare beneficiaries received non-indicated cardiac tests, and 10 percent of DXAs reimbursed by Medicare were administered at inappropriately short intervals. There is significant geographic variation in the provision of these services. (2) Carefully designed policy and payment changes will likely prove most effective in reducing low-value care.

[Appropriateness of diagnostic tests in cardiovascular prevention: what can we skip?]

In recent years, a huge increase in the use of cardiac procedures, both invasive and non-invasive, was observed. Diagnostic tests, mainly non-invasive tests, are often prescribed inappropriately, in most cases replacing the clinical evaluation. The rate of inappropriate tests in cardiology is largely variable, depending on regional issues and different medical approach. When the test entails radiation exposure, the biological risk for both the patient and the environment must be taken into account. For this reason, the test that results in less biological risk should always be preferred as a first step.Moreover, it has not been clearly demonstrated that some diagnostic tests help to improve the outcome, that is to prevent cardiovascular events. As many as one sixth of the patients who undergo stress imaging are not taking proper medication, and very frequently no change in therapy is made after the test, regardless of the outcome. Since the appropriateness of diagnostic evaluation requests is mandatory, we focused on the diagnostic tests usually performed in primary and secondary prevention that carry no contribution to the clinical management of patients. This review addresses the need to optimize available resources, reduce costs and avoid unnecessary cardiovascular assessments, thereby enhancing the more efficient care delivery models.

Usefulness of a low CHADS2 or CHA2DS2-VASc score to predict normal diagnostic testing in emergency department patients with an acute exacerbation of previously diagnosed atrial fibrillation

International guidelines do not specify what testing should be performed during emergency department (ED) evaluations for patients presenting with an exacerbation of previously diagnosed atrial fibrillation (AF). We hypothesized that low CHADS2 and CHA2DS2-VASc scores predict normal routine diagnostic testing in these patients. We conducted an analysis within a prospective observational cohort study at a university-affiliated hospital. We included patients with previously diagnosed AF and who presented to the ED primarily for an AF-related complaint. Logistic regression was used to analyze the association between CHADS2 and CHA2DS2-VASc scores and abnormal results for blood counts, electrolytes, cardiac markers, thyroid function, and chest x-rays. We included 216 patients in this analysis. The odds ratios (95% confidence interval) for each point increase in CHADS2 for abnormal blood counts, electrolytes, troponin I, brain natriuretic peptide, thyroid function, and chest x-ray were 1.28 (0.99 to 1.65), 1.48 (1.19 to 1.84), 1.42 (1.10 to 1.82), 1.66 (1.15 to 2.41), 0.95 (0.70 to 1.29), and 1.17 (0.94 to 1.44), respectively. The corresponding odds ratios (95% confidence interval) for each point increase in CHA2DS2-VASc were 1.17 (0.96 to 1.42), 1.27 (1.09 to 1.49), 1.30 (1.07 to 1.57), 1.57 (1.18 to 2.10), 0.98 (0.79 to 1.22), and 1.14 (0.97 to 1.33), respectively. Among ED patients with established AF who underwent evaluation for acutely symptomatic AF, nearly 3/4 of routine diagnostic tests return to normal. In conclusion, patients with CHADS2 or CHA2DS2-VASc score of 0 have the lowest likelihood of abnormal studies and may represent an easily identifiable group of patients who need fewer ED tests.

[Choosing wisely: the Top 5 list of the Italian Association of Hospital Cardiologists (ANMCO)]

In recent years, a progressive increase in the number of medical diagnostic and interventional procedures has been observed, namely in cardiology. A significant proportion of them appear inappropriate, i.e. potentially redundant, harmful, costly, and useless. Recently, the document Medical Professionalism in the New Millennium: A Physician Charter, the American Board of Internal Medicine (ABIM) Foundation Putting the Charter into Practice program, JAMA's Less Is More and BMJ's Too Much Medicine series, and the American College of Physicians' High-Value, Cost-Conscious Care initiatives, have all begun to provide direction for physicians to address pervasive overuse in health care. In 2010, the Brody's proposal to scientific societies to indicate the five medical procedures at high inappropriateness risk inspired the widely publicized ABIM Foundation's Choosing Wisely campaign. As part of Choosing Wisely, each participating specialty society has created lists of Things Physicians and Patients Should Question that provide specific, evidence-based recommendations physicians and patients should discuss to help make wise decisions about the most appropriate individual care. In Italy, Slow Medicine launched the analogue campaign Fare di più non significa fare meglio. The Italian Association of Hospital Cardiologists (ANMCO) endorsed the initiative by recognizing the need to optimize available resources, reduce costs and avoid unnecessary cardiovascular assessments, thereby enhancing the more efficient care delivery models. An ad hoc ANMCO Working Group prepared a list of five cardiac procedures that seem inappropriate for routine use in our country and, after an internal revision procedure, these are presented here.

Cardiovascular disease and bridging the diagnostic gap

Cardiovascular disease (CVD) is now the leading cause of death worldwide. It continues to be on the rise and has become a true pandemic that has no respect to borders.' Coronary artery disease (CAD) is the most common type of CVD. It continues to be the leading cause of mortality both in men and women in the U.S.' Approximately every 25 seconds, an American will suffer an acute coronary syndrome, and approximately every minute someone will die of one. Risk stratification and early disease detection continue to be the bedrock of most preventative strategies. Risk assessment tools like Framingham Heart Score (FHS used in the U.S.), prospective cardiovascular monster (PROCAM used in Germany), or systemic coronary risk evaluation (SCORE used in Europe) are among the common and widely available estimators of a multi-factorial absolute risk of developing CVD.6 Recently, coronary artery calcium (CAC) has emerged as a non-invasive modality that might improve prediction of future cardiovascular events. We have conducted a comprehensive review of CVD risk factors, risk assessment and screening tools being applied to aid in early detection of CVD. As we work on bridging the diagnostic gap of the leading cause of mortality across the globe, utility of accurate and sensitive risk assessment and screening tools for early CVD detection is vital. This will aid in our goal of early detection, modifying risk factors and prevention of CVD incidence.

RADStation3G: a platform for cardiovascular image analysis integrating PACS, 3D+t visualization and grid computing

RADStation3G is a software platform for cardiovascular image analysis and surgery planning. It provides image visualization and management in 2D, 3D and 3D+t; data storage (images or operational results) in a PACS (using DICOM); and exploitation of patients' data such as images and pathologies. Further, it provides support for computationally expensive processes with grid technology. In this article we first introduce the platform and present a comparison with existing systems, according to the platform's modules (for cardiology, angiology, PACS archived enriched searching and grid computing), and then RADStation3G is described in detail.

When to remeasure cardiovascular risk in untreated people at low and intermediate risk: observational study

OBJECTIVE

To estimate the probability of becoming high risk for cardiovascular disease among people at low and intermediate risk and not being treated for high blood pressure or lipid levels.

DESIGN

Observational study.

SETTING

General communities in Japan and the United States.

PARTICIPANTS

13,757 participants of the Tokyo health check-up study and 3855 of the Framingham studies aged 30-74 years with complete data on risk equation covariates, not receiving blood pressure or cholesterol lowering treatment, and with an estimated risk of cardiovascular disease <20% within 10 years. We stratified participants on the basis of baseline risk: <5%, 5-<10%, 10-<15%, and 15-<20%.We used follow-up measurements from the Tokyo study done annually over three years (2006-10) and follow-up visits in the Framingham study done between eight (1968-75) and 19 years (1990-1995) after baseline.

MAIN OUTCOME MEASURE

Estimated 10 year risk of a cardiovascular event >20% using the Framingham equation.

RESULTS

At baseline most participants had <5% risk (60.6% of Tokyo cohort and 45.7% of Framingham cohort) or 5-<10% risk (24.0% and 28.0%, respectively) of a cardiovascular event within 10 years. There was <10% probability of crossing the treatment threshold at 19, 8, and 3 years for baseline risk groups <5%, 5-<10%, and 10-<15%, respectively, and >10% probability of crossing the treatment threshold at one year for the 15-<20% baseline risk group.

CONCLUSIONS

Decisions on the frequency of remeasuring for cardiovascular risk should be made on the basis of baseline risk. Repeat risk estimation before 8-10 years is not warranted for most people initially not requiring treatment. However, remeasurement within a year seems warranted in those with an initial 15-<20% risk.

[The estimation of correlation dependences between the results of clinical examination and screening diagnostics of the risk factors of the development of cardiovascular diseases in the women of late reproductive age]

The results of clinical trials give evidence of the close correlation between the data obtained by clinical, biochemical, and instrumental methods and the data of screening studies designed to estimate the risk factors responsible for the development of cardiovascular diseases in the women of late reproductive age.

[Medical and surgical health care for congenital heart disease: a panoramic vision of the reality in Mexico. Inquiry 2009]

INTRODUCTION

The only way to characterize the Mexican problem related to congenital heart disease care is promoting the creation of a national database for registering the organization, resources, and related activities.

MATERIAL AND METHODS

The Health Secretary of Mexico adopted a Spanish registration model to design a survey for obtaining a national Mexican reference in congenital heart disease. This survey was distributed to all directors of medical and/or surgical health care centers for congenital heart disease in Mexico. This communication presents the results obtained in relation to organization, resources and activities performed during the last year 2009.

RESULTS

From the 22 health care centers which answered the survey 10 were reference centers (45%) and 12 were assistant centers (55%). All of them are provided with cardiologic auxiliary diagnostic methods. Except one, all centers have at least one bidimentional echocardiography apparatus. There is a general deficit between material and human resources detected in our study. Therapeutic actions for congenital heart disease (70% surgical and 30% therapeutical interventionism) show a clear centralization tendency for this kind of health care in Mexico City, Monterrey and finally Guadalajara.

CONCLUSIONS

Due to the participation of almost all cardiac health centers in Mexico, our study provides an important information related to organization, resources, and medical and/or surgical activities for congenital heart disease. The data presented not only show Mexican reality, but allows us to identify better the national problematic for establishing priorities and propose solution alternatives.

[Evidence-based cardiology: practical applications from epidemiology. III. Diagnostic capacity of a clinical test]

This article reviews different characteristics of validity in a clinical diagnostic test. In particular, we emphasize the likelihood ratio as an instrument that facilitates the use of epidemiologic concepts in clinical diagnosis.

Clinical profile and management of patients with chronic ischemic heart disease according to age in the population daily attended by cardiologists in Spain The ELDERCIC study

OBJECTIVES

This study was aimed to evaluate the differences according to age in the clinical profile and management of outpatients with chronic ischemic heart disease attended by cardiologists in Spain.

METHODS

Patients with an established diagnosis of chronic ischemic heart disease were included in this cross-sectional multicenter study. The age of 65 years was considered as the cut-off point for the present analysis.

RESULTS

A total of 1038 subjects were included, 524 of them (50.5%) >65 years. Patients >65 years had a lesser prevalence of smoking, a longer history of hypertension, a worse left ventricular ejection fraction and a higher prevalence of heart failure and renal insufficiency than younger subjects. The number of prescribed drugs was higher in patients >65 years (6.1+/-1.9 vs 5.7+/-2.1, p=0.004). Blood pressure control rate was lower in older patients (38.1% vs 46.5%, p=0.008). No significant differences were found either in LDL-cholesterol (42.4% vs 46.5%), or glycemic control rates (42.4% vs 41.4%), both p=NS. Diagnostic and therapeutic procedures were also compared in >65 vs < or =65 years, exercise test was performed in 51.5% vs 62.8% (p<0.0001); stress echocardiography in 18.3% vs 13.2% (p=0.027); coronary angiography in 38.6% vs 53.5% (p<0.0001); and coronary revascularization in 37.2% vs 46.9% (p=0.002), without significant differences in electrocardiogram, echocardiogram, or isotopic exams.

CONCLUSIONS

Older patients exhibited a worse clinical profile and a worse blood pressure control rate than the younger. However, diagnostic and therapeutic procedures appear to be frequently underused in the old patients.

Non-cardiac arterial disease in Catalonia: patient profiles and quality of clinical records by characteristics of the Vascular Surgery Unit

AIM

Non-cardiac arterial disease (NCAD) is a frequent cause of hospital admission. The aim of this study was to investigate differences in patient profiles and clinical records as a function of the size of the Vascular Surgery Unit (VSU).

METHODS

Retrospective observational study. Stratified cluster sampling and selection of patients hospitalized for NCAD.

ANALYSIS

1) description of patient profiles, quality of clinical records, and VSU [availability of diagnostic (DR) and therapeutic (TR) resources, and of written protocols (WP)]; 2) association between these variables and size of VSU.

RESULTS

The sample consisted of 14 hospitals, 6 with a VSU of 15 or fewer beds (VSU < or = 15B) and 8 with >15 beds (VSU >15B). The mean number of DRs, TRs and WPs was 9, 2.8 and 2 in VSUs < or = 15B, and 11.5, 6.5 and 3.3 in VSUs >15B. The proportion of patients older than 70, female, with ischemic disease, or with coexisting diabetes was significantly higher in VSUs < or = 15B (67%, 31%, 95% and 57%, respectively) than in VSUs >15B (58%, 22%, 69% and 48%). Comorbid conditions and treatment during admission and at discharge were documented significantly less frequently in the clinical records in VSUs < or = 15B. Risk factors were under-reported in the clinical records of both types of VSU.

CONCLUSION

Patient profiles and the quality of clinical records vary by size of VSU. Under-reporting of risk factors may hinder the implementation of prevention and treatment measures.

[The use of rhythmic Holter record in the diagnosis of unexplained syncope at the point hospital cardiology division]

Authors report the finding of the descriptive study of 36 syncope case following while 1 year (January-December 2006) in cardiology A service at the hospital of point G. The unexplained syncopes have represented 30% of the all syncopes. The female frequency sex was predominant with 58% of cases. The mean age of patients was 43 +/- SD years. The holter rhythmic during 24 hours has been productive for 58% in term of etiology research of syncope dominate essentially by the trouble of rythm at 19%.

Comparison of recent utilization trends in radionuclide myocardial perfusion imaging among radiologists and cardiologists

PURPOSE

To study recent practice patterns in radionuclide myocardial perfusion imaging (MPI) and related procedures among radiologists, cardiologists, and other physicians.

METHODS AND MATERIALS

The nationwide Medicare administrative Part B claims summary databases from 1998 and 2002 were used to assess utilization rate changes in the 4 primary procedure codes for MPI, the seven codes for diagnostic cardiac catheterization with coronary angiography, and the single code for stress echocardiography. Rate changes among radiologists, cardiologists, and other physicians were determined for the total Medicare population, as well as for the 3 primary places of service at which imaging is formed: hospital inpatient facilities, hospital outpatient facilities, and private offices. Ratios of the use of the 2 supplementary codes for left ventricular (LV) wall motion and ejection fraction to that of the primary MPI codes were calculated for 2002.

RESULTS

The utilization rate per 1000 Medicare beneficiaries of MPI rose among radiologists from 19.8 in 1998 to 20.1 in 2002, a 2% increase. The rate among cardiologists rose from 22.9 in 1998 to 40.7 in 2002, a 78% increase. Most of this growth occurred in cardiologists' offices, where the utilization rate increased 101% over the 4 years. In 2002, the ratios of the use of the supplementary LV wall motion and ejection fraction codes to that of the primary MPI codes were 1.73 for cardiologists and 1.46 among radiologists. Between 1998 and 2002, the utilization of diagnostic cardiac catheterization among cardiologists increased by 19%, and their utilization of stress echocardiography increased by 21%.

CONCLUSION

In recent years within the Medicare population, the rate of utilization of MPI among radiologists has remained relatively stable, whereas it has risen sharply among cardiologists. The greatest growth was seen in cardiologists' private offices. This raises concerns about possible inappropriate utilization of MPI and also about the potential effect self-referral has on this utilization trend. The increased use of MPI by cardiologists did not result in reduction in their use of either cardiac catheterization with coronary angiography or stress echocardiography.

Prevalence, referral patterns, testing, and surgery in aortic valve disease: leaving women and elderly patients behind?

BACKGROUND AND AIM OF THE STUDY

The prevalence of aortic valve disease is not well defined, and it is not known to what degree gender and age affect testing and surgery for this condition. The study aim was to describe the prevalence of aortic valve disease in the United States population by extrapolating from administrative claims databases; and to investigate differences associated with gender and age in referral, diagnostic testing, and aortic valve replacement (AVR).

METHODS

A claims database of approximately five million privately insured beneficiaries and a 5% sample of Medicare beneficiaries were queried for patients with aortic valve disease. Prevalence was calculated by age group and gender, and extrapolated to the 2005 US population. The proportion of patients with a cardiologist or cardiovascular surgeon visit, performance of echocardiography or stress testing, and AVR within a year of diagnosis was determined.

RESULTS

The extrapolated prevalence of aortic valve disease in the US in 2005 was 1.8% (approximately 5.2 million people); in persons aged > or =65 years, prevalence was 10.7%. Women were seen by a specialist, underwent diagnostic tests and underwent AVR at rates significantly lower than men, as did patients aged > or =80 years compared to those aged 65-79 years. AVR was performed at approximately half the rate in women (1.4%) compared to men (2.7%, p <0.001), and in patients aged > or =80 years (1.1%) compared to those aged 65-79 years (2.5%, p <0.001).

CONCLUSION

In 2005, approximately 5.2 million adults in the US were estimated to have a diagnosis of aortic valve disease. Advanced age and female gender were associated with lower rates of specialist visits, diagnostic testing, and AVR.

Disparities in utilization of coronary artery disease treatment by gender, race, and ethnicity: opportunities for prevention

Racial, ethnic, (R/E) and gender disparities in access to health services in the United States and their relationship to adverse health outcomes are well established. Despite an increase in evidence-based cardiovascular treatment, gender, racial, and ethnic disparities in coronary artery disease (CAD) treatment persist. There is neither currently a comprehensive framework for understanding why disparities occur in cardiovascular disease care, nor viable solutions for intervention. This article synthesizes the literature on disparities in coronary artery disease with a conceptual model for understanding chronic disease disparities. This article follows the natural history of disease to observe where differences arise, beginning with health risk management, screening, diagnosis, treatment, and rehabilitation. Racial, ethnic, and gender differences were found at every step of this continuum, including a higher burden of risk factors and a less likelihood of receiving needed lifesaving cardiac procedures. Unfortunately, there is a dearth of intervention strategies to reduce racial, ethnic, and gender disparities in coronary artery disease. Comprehensive solutions will require addressing the barriers at the system, the provider, and the patient level. An early intervention approach that addresses multiple risk factors should be a high priority.

Normality of upper and lower peripheral pulse transit time of normotensive and hypertensive children

OBJECTIVES

The ankle-brachial index (ABI) is known to be indicative of sub-clinical peripheral arterial diseases that are correlated with cardiovascular disease risk factors like atherosclerosis or ischemic extremity. Due to its occluding measurement nature, this may not be appealing to less cooperative patients when multiple prolonged screening is required. A simple and non-intrusive approach termed pulse transit time ratio (PTTR) has recently shown to be potential surrogate marker for the prolonged ABI measurement. Other studies have also suggested that subjects with hypertension have stiffer arterial wall and thereby can confound transit time related parameters. Thus, it becomes important to understand the PTTR normality and difference of hypertensive children when compared to those measured from normotensive children.

METHODS

About 55 normotensive (39 male; aged 8.4 +/- 2.3 yr) and 4 hypertensive (4 male; aged 5-10 yr) Caucasian children were recruited from the same geographical location. A customized device was used to compute pulse transit time related measurements. Since the PTTR approach produced a delta value that was similar to that of ABI, possible inter-subject physiologic differences had limited confounding effects on the derived PTTR parameter.

RESULTS

The obtained transit time measurements from the hypertensive children had lower pulse transit time value when compared to their normotensive counterparts. However, the statistical analysis indicated that they had insignificant PTTR difference (p > 0.01) from those seen in the normotensive children.

CONCLUSIONS

The findings herein suggest that stiffer arterial wall may have confounding effects on the derived transit time related measurements but it is limited on the PTTR parameter. Similar to the ABI approach, PTTR may be only confounded by abnormal local changes in either of the measured peripheral arterial wall. Hence, the PTTR technique shows promise to be an ABI marker from this perspective.

What is the role of non-invasive measurements of atherosclerosis in individual cardiovascular risk prediction?

Primary prevention of CVD (cardiovascular disease) is mainly based on the assessment of individual cardiovascular risk factors. However, often, only the most important (conventional) cardiovascular risk factors are determined, and every level of risk factor exposure is associated with a substantial variation in the amount of atherosclerosis. Measuring the effect of risk factor exposure over time directly in the vessel might (partially) overcome these shortcomings. Several non-invasive imaging techniques have the potential to accomplish this, each of these techniques focusing on a different stage of the atherosclerotic process. In this review, we aim to define the current role of various of these non-invasive measurements of atherosclerosis in individual cardiovascular risk prediction, taking into account the most recent insights about validity and reproducibility of these techniques and the results of recent prospective outcome trials. We conclude that, although the clinical application of FMD (flow-mediated dilation) and PWA (pulse wave analysis) in individual cardiovascular risk prediction seems far away, there may be a role for PWV (pulse wave velocity) and IMT (intima-media thickness) measurements in the near future.

[Potential risk caused by the lack of recognition of coronary spasm: analysis of the coronary spasm questionnaire in Japan]

BACKGROUND

The spasm provocation test (SPT)is no longer widely used in patients with undiagnosed chest pain syndromes in the USA and Europe. Objectives. The clinical significance of the SPT was examined in Japan and compared with the frequency of coronary spastic angina (CSA) in institutions with and without SPT screening.

METHODS AND RESULTS

Questionnaires concerning the number of cases of coronary angiography (CAG), percutaneous coronary intervention (PCI), and invasive/non-invasive SPT in 2005 were sent to members of the Japanese Circulation Society in 1,177 cardiology hospitals. Completed surveys were returned from 208 hospitals (17.7%). Non-invasive SPT was performed in only 27 hospitals (13.0%). Invasive SPT was not performed in 50 (24.0%) institutions, and performed in the remaining 158 institutions(< 10 cases/year: 29.8%, > or = 10< 50: 33.7%, > or = 50< 100: 8.7%, > or = 100: 3.8%). There was a close correlation between the number of acetylcholine/ergonovine SPTs and the number of CSA cases finally diagnosed (acetylcholine: r(2)= 0.907, ergonovine: r(2) = 0.76). There was no difference in the number/year of CAG (525+/-451 vs 513 +/-888, NS) and PCI(175+/-156 vs 144+/-225, NS) between institutions with and without SPT screening. However, the number of CSA cases (15.6+/-21.6 vs 4.2 +/-13.0, p < 0.01) and variant angina cases (3.3+/-7.2 vs 1.4+/-2.4)in hospitals with SPT screening was higher than hospitals without SPT screening.

CONCLUSIONS

If Japanese cardiologists discontinue use of the SPT as in the USA and Europe, occurrence of CSA may disappear in the near future in Japan.

Diagnosis and Management of Subclavian Artery Stenosis Prior to Coronary Artery Bypass Grafting in the Current Era

There are several approaches to managing subclavian artery stenosis (SAS) prior to coronary artery bypass grafting (CABG) with an intended internal thoracic artery (ITA) graft to the left anterior descending (LAD) artery. We herein review the incidence of and various diagnostic modalities for detecting SAS. Published relevant clinical studies from the interventional cardiovascular and cardiac surgical literature are summarized. Particular emphasis is placed on the efficacy of various approaches to the patient diagnosed with SAS prior to CABG. Stenting the subclavian artery prior to bypass surgery and using an in situ ITA is compared to using the ITA as a "free" graft. The incidence of restenosis after subclavian artery angioplasty or stenting is not trivial and has been reported to occur at a rate of 6% to 21%; however, the average rate of restenosis with stenting appears to be in the mid-teens. Subacute subclavian stent thrombosis or occlusion is exceptionally rare, suggesting that a percutaneous approach to SAS is reasonable prior to CABG. For patients requiring emergent revascularization, placement of a free ITA graft to the LAD appears to be a safe and durable treatment as patency rates are comparable to that of an in situ LITA to the LAD. In summary, although no randomized clinical trials address the optimal management of SAS prior to CABG, both percutaneous and surgical options appear to be safe and reasonably durable.

The use of invasive cardiac procedures after acute myocardial infarction in long-term dialysis patients

BACKGROUND

Dialysis patients have an excessive risk of cardiovascular death after myocardial infarction (MI). Underutilization of cardiac therapies may partially explain this risk, but whether patients on maintenance dialysis have differential rates of coronary angiography or revascularization during admission for MI compared with patients not on dialysis and whether these differences are explained by the presence of comorbid illness were uncertain.

METHODS

We analyzed 154,692 patients with a primary diagnosis of MI in the 2001 National Inpatient Sample, and we compared procedure use in patients on long-term dialysis, patients with non-dialysis-dependent chronic kidney disease (CKD), or normal renal function.

RESULTS

Dialysis patients and patients with dialysis-independent CKD were significantly less likely to undergo coronary angiography than patients with normal renal function (39% and 34% vs 56%). They were also less likely to undergo coronary revascularization (19% and 23% vs 41%) or to have a coronary intervention after diagnostic angiography (46% and 62% vs 70%). After adjustment, these differences remained, with a lower likelihood of angiography (42% and 45% vs 56%), revascularization (22% and 31% vs 41%), or coronary intervention after diagnostic angiography (52% and 66% vs 70%).

CONCLUSIONS

Despite a high mortality rate after MI, patients on dialysis are markedly less likely than patients with dialysis-independent CKD or normal renal function to undergo diagnostic angiography or coronary revascularization after admission for MI. Additional studies to determine how these disparities are related to mortality are warranted.

Integral-based identification of patient specific parameters for a minimal cardiac model

A minimal cardiac model has been developed which accurately captures the essential dynamics of the cardiovascular system (CVS). However, identifying patient specific parameters with the limited measurements often available, hinders the clinical application of the model for diagnosis and therapy selection. This paper presents an integral-based parameter identification method for fast, accurate identification of patient specific parameters using limited measured data. The integral method turns a previously non-linear and non-convex optimization problem into a linear and convex identification problem. The model includes ventricular interaction and physiological valve dynamics. A healthy human state and four disease states, valvular stenosis, pulmonary embolism, cardiogenic shock and septic shock are used to test the method. Parameters for the healthy and disease states are accurately identified using only discretized flows into and out of the two cardiac chambers, the minimum and maximum volumes of the left and right ventricles, and the pressure waveforms through the aorta and pulmonary artery. These input values can be readily obtained non-invasively using echo-cardiography and ultra-sound, or invasively via catheters that are often used in Intensive Care. The method enables rapid identification of model parameters to match a particular patient condition in clinical real time (3-5 min) to within a mean value of 4-10% in the presence of 5-15% uniformly distributed measurement noise. The specific changes made to simulate each disease state are correctly identified in each case to within 10% without false identification of any other patient specific parameters. Clinically, the resulting patient specific model can then be used to assist medical staff in understanding, diagnosis and treatment selection.

Accuracy of noninvasive ejection fraction measurement in a large community-based clinic

OBJECTIVE

Compare the agreement of two dimensional echocardiography (echocardiography) and electrocardiogram (ECG)-gated single photon emission computed tomography (SPECT), with left ventricular contrast angiography (angiography) for the evaluation of left ventricular ejection fraction (LVEF).

DESIGN

Retrospective cohort study.

DATA SOURCE

American College of Cardiology National Cardiovascular Data Registry(TM) (ACC-NCDR).

PARTICIPANTS

Patients from a large, community-based clinic in central Wisconsin.

METHODS

Consecutive patients (1999-2002) were identified from the ACC-NCDR dataset who underwent angiography and echocardiography or SPECT within 1 month of each other for evaluation of LVEF. Noninvasive LVEF values were compared to those obtained by angiography using the paired t-test. Regression analysis was used to assess the relation between the compared methods. Bland-Altman analyses were performed to assess the agreement between LVEF values obtained by the noninvasive techniques and angiography. Sensitivity and specificity of detecting depressed LVEF were determined for noninvasive techniques. Regression equations were determined for estimating angiographic values from the echocardiographic or SPECT values.

RESULTS

Five hundred thirty-four patients underwent 542 angiographic studies: SPECT in all 534 patients, combined SPECT and echocardiographic studies in 201 patients, and combined angiographic and echocardiographic studies in 202 patients. Correlation of angiographic LVEFs with both echocardiographic and SPECT LVEFs was significant (r = 0.70 and r = 0.69, respectively; p < 0.0001). Echocardiographic LVEFs were lower than those determined by angiography (49% +/- 1.0% versus 54% +/- 1.0%; p < 0.0001). SPECT LVEFs were also lower than angiographic LVEFs (49% +/- 0.6% versus 57% +/- 0.6%; p < 0.0001). For 201 patients who underwent both SPECT and echocardiography, SPECT LVEFs were lower (47% +/- 1.0% for SPECT versus 49% +/- 1.0% for echocardiography; p < 0.05). Bland-Altman analysis revealed widely varying differences between techniques with broad confidence intervals. Nonetheless, sensitivity and specificity for determining LVEFs of <40% for SPECT and echocardiography were 90% and 86%, and 75% and 89%, respectively. LVEF of < or = 35% was correctly assessed by both SPECT and echocardiography. Sensitivity and specificity for SPECT were 82% and 89%, and 81% and 88% for echocardiography.

CONCLUSION

At our institution, LVEFs obtained noninvasively by echocardiography or SPECT are lower than angiographic LVEFs with widely fluctuating differences. Regression equations can be used to correct the noninvasive readings. Although lower, noninvasive techniques appear to accurately assess depressed LVEFs (<40% and <35%). The accuracy of noninvasive techniques for the evaluation of LVEF should be considered when managing and determining prognoses of patients with cardiac conditions. Individual institutions should determine the validity of the noninvasive techniques they use to assess LVEF.

Race/Ethnic Disparities in Utilization of Lifesaving Technologies by Medicare Ischemic Heart Disease Beneficiaries

OBJECTIVE

The objective of this study was to explain race/ethnic disparities in hospitalizations, utilization of high-technology diagnostic and revascularization services, and mortality of elderly ischemic heart disease (IHD) patients.

DESIGN

A longitudinal Medicare claims database of all Part A hospital and Part B physician services provided elderly patients admitted for IHD in 1997 is used to construct admission, utilization, and mortality rates for whites and blacks, Asians, Hispanics, and American Indians. Z-scores are used to test differences in rates between whites and minorities at the 99% confidence level. Logistic and proportional hazard models are used to predict the likelihood of revascularization and its effects on race/ethnic survival 2 years postdischarge.

SETTING

The setting of this study was an acute hospital supplemented by all ambulatory Part B outpatient providers of care.

PATIENTS/PARTICIPANTS

Participants included all 700,000 age 65+ Medicare beneficiaries in fee-for-service identified with IHD as a primary diagnosis on admission in 1997.

MEASUREMENTS AND MAIN RESULTS

Whites were 26% more likely to be admitted for IHD than blacks, 50% more likely than Asians, 5% more than American Indians, but 3% less likely than Hispanics. Once admitted, elderly blacks and American Indians undergo invasive diagnostic and surgical revascularization far less often than whites (P < 0.01), although blacks are equally as likely as whites to be admitted to an open heart hospital. Controlling for other factors, whites reduce their 2-year mortality by 20% by undergoing revascularization 41% of the time. Blacks gain only 11% as a result of much lower rates and gains to revascularization than whites. Asians and Hispanics were slightly more likely than whites to undergo revascularization but gain less than whites from the procedure.

CONCLUSIONS

Despite having similar Medicare health insurance coverage, elderly utilization and IHD mortality rates differ markedly not only between whites and minorities, but within minority groups themselves. A large, nationally representative survey of physicians and patients is needed to distinguish between systemwide "failures to refer" and patient "aversions to surgery" as explanations for lower black rates of surgical interventions.

Acute Coronary Syndrome patients in New Zealand receive less invasive management when admitted to hospitals without invasive facilities

AIM

To compare differences in the presentation and management of acute coronary syndrome (ACS) patients presenting to interventional versus non-interventional New Zealand hospitals.

METHODS

We assessed the data collected by the New Zealand Cardiac Society ACS Audit Group over 14 days from each hospital in New Zealand (n=36) that admits ACS patients. Patient management at intervention centres (5 public, 3 private) was compared with non-intervention centres (28 public). Investigations and revascularisation procedures performed on transferred patients were attributed to the referring centre.

RESULTS

From 0000 hours on 13 May 2002 to 2400 hours on 26 May 2002, 930 patients were admitted to a New Zealand hospital with a suspected or definite ACS: ST-segment-elevation myocardial infarction [STEMI] (11%), non-STEMI (31%), unstable angina pectoris [UAP] (36%), or another cardiac or medical diagnosis (22%). Patients admitted to a non-intervention centre (n=612) were the same age (median 70 years) with similar risk factors, but were more likely to be Maori (8.2% vs 3.8%, p=0.0063) and were less likely to have a history of prior cardiac angiography (26% vs 28%, p=0.02) or percutaneous coronary intervention [PCI] (9.6% vs 14%, p=0.03) than patients admitted to an intervention centre (n=318). Patients admitted to a non-intervention centre were more likely to have a chest X-ray (88% vs 81%, p<0.0024), as likely to have an exercise treadmill test (20% vs 22%, p=0.39), but less likely to receive an echocardiogram (17% vs 26%, p<0.0005), a cardiac angiogram (17% vs 30%, p<0.0001), or neither a treadmill nor a cardiac angiogram (68% vs 53%, p<0.0001) for cardiac risk assessment. For patients with a definite ACS presentation (STEMI, Non-STEMI, UAP, n=721), PCI was performed less often for patients admitted to non-intervention centres: 3% vs 14% (p<0.0001), although the rate of coronary artery bypass grafting was similar: 3% vs 5% (p=0.16).

CONCLUSION

Patients admitted to a hospital without cardiac interventional facilities receive fewer investigations and less revascularisation than patients admitted to Intervention Centres. Hence patients admitted with an acute coronary syndrome in New Zealand receive inequitable management. A comprehensive National strategy is needed to improve access to optimal cardiac care.

Binary classification of dyslipidemia from the waist-to-hip ratio and body mass index: a comparison of linear, logistic, and CART models

Background

We sought to improve upon previously published statistical modeling strategies for binary classification of dyslipidemia for general population screening purposes based on the waist-to-hip circumference ratio and body mass index anthropometric measurements.

Methods

Study subjects were participants in WHO-MONICA population-based surveys conducted in two Swiss regions. Outcome variables were based on the total serum cholesterol to high density lipoprotein cholesterol ratio. The other potential predictor variables were gender, age, current cigarette smoking, and hypertension. The models investigated were: (i) linear regression; (ii) logistic classification; (iii) regression trees; (iv) classification trees (iii and iv are collectively known as "CART"). Binary classification performance of the region-specific models was externally validated by classifying the subjects from the other region.

Results

Waist-to-hip circumference ratio and body mass index remained modest predictors of dyslipidemia. Correct classification rates for all models were 60–80%, with marked gender differences. Gender-specific models provided only small gains in classification. The external validations provided assurance about the stability of the models.

Conclusions

There were no striking differences between either the algebraic (i, ii) vs. non-algebraic (iii, iv), or the regression (i, iii) vs. classification (ii, iv) modeling approaches. Anticipated advantages of the CART vs. simple additive linear and logistic models were less than expected in this particular application with a relatively small set of predictor variables. CART models may be more useful when considering main effects and interactions between larger sets of predictor variables.

Creating a useful vascular center: a statewide survey of what primary care physicians really want

OBJECTIVE

Multidisciplinary vascular centers (VCs) have been proposed to integrate vascular patient care. No studies, however, have assessed referring physician interest or which services should be provided. A statewide survey of primary care physicians (PCPs) was performed to answer these questions.

METHODS

Questionnaires were mailed to 3711 PCPs, asking about familiarity with vascular disease, potential VC usage, and services VCs should provide. Univariate and multivariate analysis was used to determine which PCPs would refer patients, the services desired, and which patients would be referred.

RESULTS

Of 1006 PCPs who responded, 66% would refer patients to a VC, especially patients younger than 50 years (P<.001) and those with lower extremity disease (P<.001) or abdominal aortic aneurysm (P<.001). PCPs practicing within 50 miles of a VC (P<.001), those in practice less than 5 years (P<.001), and those without specific training in vascular disease during residency (P=.004) were most likely to refer patients. Vascular surgery (97%), interventional radiology (90%), and a noninvasive vascular laboratory (82%) were considered the most important services, and physician educational services (62%) were also desirable. PCPs did not think cardiology, cardiac surgery, smoking cessation programs, or diabetes or lipid management are needed. Reasons for VC nonuse included travel distance (23%), sufficient local services (21%), and insurance issues (12%). Only 16% of PCPs believe that their patients with vascular disease currently receive optimal care.

CONCLUSION

There is considerable interest in VCs among PCPs. In contrast to recently described models, VCs need not incorporate cardiology, cardiac surgery, smoking cessation programs, or diabetes or lipid management. VCs should include vascular surgery, interventional radiology, a noninvasive vascular laboratory, and physician educational services.

Examination of gender bias in the evaluation and treatment of angina pectoris by cardiologists

One hundred fifty-eight patients (76 men and 82 women) presenting to an outpatient cardiology clinic with a new complaint of angina were prospectively followed to determine if there was a gender bias in the management of suspected coronary artery disease when physicians trained in cardiology managed their care. Overall, there were no differences in the percentage of women who underwent noninvasive evaluation, invasive evaluation, and treatment of suspected coronary artery disease compared with men.

Does the ownership of the admitting hospital make a difference? Outcomes and process of care of Medicare beneficiaries admitted with acute myocardial infarction

BACKGROUND

Concerns have been expressed about quality of for-profit hospitals and their use of expensive technologies.

OBJECTIVE

To determine differences in mortality after admission for acute myocardial infarction (AMI) and in the use of low- and high-tech services for AMI among for-profit, public, and private nonprofit hospitals.

STUDY DESIGN, SETTING, AND PATIENTS

Cooperative Cardiovascular Project data for 129,092 Medicare patients admitted for AMI from 1994 to 1995.

MAIN OUTCOME MEASURES

Mortality at 30 days and 1 year postadmission; use of aspirin, angiotensin-converting enzyme (ACE) inhibitors, beta-blockers at discharge, thrombolytic therapy, catheterization, percutaneous transluminal coronary angioplasty (PTCA), and coronary artery bypass graft (CABG) compared by ownership.

RESULTS

Mortality rates at 30 days and at 1 year at for-profit hospitals were no different from those at public and private nonprofit hospitals. Without patient illness variables, nonprofit hospitals had lower mortality rates at 30 days (relative risk [RR], 0.95; 95% confidence interval [CI], 0.91-0.99) and at 1 year (RR, 0.96; 95% CI, 0.93-0.99) than did for-profit hospitals, but there was no difference in mortality between public and for-profit hospitals. Beneficiaries at nonprofit hospitals were more likely to receive aspirin (RR, 1.04; 95% CI, 1.03-1.05) and ACE inhibitors (RR, 1.05; 95% CI, 1.02-1.08) than at for-profit hospitals, but had lower rates of PTCA (RR, 0.91; 95% CI, 0.86-0.96) and CABG (RR, 0.93; 95% CI, 0.86-1.00).

CONCLUSIONS

Although outcomes did not vary by ownership, for-profit hospitals were more likely to use expensive, high-tech procedures. This pattern appears to be the result of for-profit hospitals' propensity to locate in areas with demand for high-tech care for AMI.

Comparison between measures of atherosclerosis and risk of stroke: the Rotterdam Study

BACKGROUND AND PURPOSE

Several measures of atherosclerosis predict the risk of stroke. However, a comparison between various measures of atherosclerosis is lacking, and limited information exists on the added value of individual measures of atherosclerosis to cardiovascular risk factors. We compared different measures of atherosclerosis in relation to stroke.

METHODS

The study was based on the prospective cohort of the Rotterdam Study and included 6913 participants who did not suffer from previous stroke. At baseline, carotid intima-media thickness and plaques, ankle-arm index, and aortic calcifications were assessed; 3996 participants (53%) had measures of all studied markers of atherosclerosis. After a mean follow-up of 6.1 years, 378 strokes occurred. Data were analyzed with Cox proportional-hazards regression and Akaike information criteria scores.

RESULTS

Carotid intima-media thickness and aortic calcifications were related most strongly to the risk of stroke (relative risk, 2.23 and 1.89; 95% confidence interval, 1.48 to 3.36 and 1.28 to 2.80 for highest versus lowest tertile, respectively). The relations between intima-media thickness, aortic calcifications, and carotid plaques and stroke remained after adjustment for cardiovascular risk factors. Intima-media thickness and aortic calcifications were related to the risk of stroke independently of each other. The relation between ankle-arm index and stroke disappeared after adjustment for cardiovascular risk factors.

CONCLUSIONS

Carotid intima-media thickness and aortic calcifications are stronger predictors of incident stroke than carotid plaque or ankle-arm indexes. They have additional value to each other and to classic risk factors and may reflect different processes.