Adenosine single photon emission computed tomography for assessing risk after myocardial infarction: recent developments

PURPOSE OF REVIEW: While the prognostic power of adenosine single photon emission computed tomography myocardial perfusion imaging has been validated in multiple patient populations including those with known or suspected coronary artery disease, the utility of this modality in assessing risk after an acute myocardial infarction in the primary angioplasty era is still a topic of debate. RECENT FINDINGS: The INSPIRE trial showed that early adenosine single photon emission computed tomography myocardial perfusion imaging is capable of identifying low-risk patients for early hospital discharge after acute myocardial infarction. This novel study demonstrated that intensive medical therapy is a reasonable strategy in low, intermediate, and high-risk post-myocardial infarction patients with preserved left ventricular function. SUMMARY: The INSPIRE trial established the role for early adenosine single photon emission computed tomography myocardial perfusion imaging as a tool for risk stratification in stable patients after an acute myocardial infarction and provided evidence that intensive medical therapy is comparable to coronary revascularization in suppressing ischemia and presumably improving cardiac outcomes. It remains to be seen whether these new findings will alter current American College of Cardiology/American Heart Association guidelines, which emphasize a primary role of coronary revascularization in acute coronary syndromes.     

Role of myocardial perfusion imaging for risk stratification in suspected or known coronary artery disease

Nuclear cardiology is an evolving specialty that has recently benefited from technological and radiopharmaceutical advances. As a result there has been an increase in the accuracy of myocardial perfusion imaging (MPI) with gated single photon emission computed tomography (SPECT) for assessing the diagnosis and prognosis of coronary artery disease. Moreover, ECG gated SPECT allows the simultaneous assessment of both myocardial perfusion and left ventricular function, which provides additional prognostic value. With increasing concern over early detection of coronary artery disease and its effective treatment, myocardial perfusion imaging is ideally placed to provide a full "one stop" functional assessment for any patient, irrespective of their exercise capacity. This applies not only to patients with chest pain but also to those with myocardial infarction, revascularisation, and heart failure, and those being assessed for non-cardiac surgery. The focus of this review is the use of myocardial perfusion imaging in risk stratification for coronary artery disease.     

Primary care management of chronic stable angina and asymptomatic suspected or known coronary artery disease: a clinical practice guideline from the American College of Physicians

In 1999, the American College of Physicians (ACP), then the American College of Physicians-American Society of Internal Medicine, and the American College of Cardiology/American Heart Association (ACC/AHA) developed joint guidelines on the management of patients with chronic stable angina. The ACC/AHA then published an updated guideline in 2002, which ACP recognized as a scientifically valid review of the evidence and background paper. This ACP guideline summarizes the recommendations of the 2002 ACC/AHA updated guideline and underscores the recommendations most likely to be important to physicians seeing patients in the primary care setting. This guideline is the second of 2 that provide guidance on the management of patients with chronic stable angina. This document covers treatment and follow-up of symptomatic patients who have not had an acute myocardial infarction or revascularization procedure in the previous 6 months. Sections addressing asymptomatic patients are also included. Asymptomatic refers to patients with known or suspected coronary disease based on a history or electrocardiographic evidence of previous myocardial infarction, coronary angiography, or abnormal results on noninvasive tests. A previous guideline covered diagnosis and risk stratification for symptomatic patients who have not had an acute myocardial infarction or revascularization procedure in the previous 6 months and asymptomatic patients with known or suspected coronary disease based on a history or electrocardiographic evidence of previous myocardial infarction, coronary angiography, or abnormal results on noninvasive tests.     

Evaluation of primary care patients with chronic stable angina: guidelines from the American College of Physicians

In 1999, the American College of Physicians (ACP), then the American College of Physicians-American Society of Internal Medicine, and the American College of Cardiology/American Heart Association (ACC/AHA) developed joint guidelines on the management of patients with chronic stable angina. The ACC/AHA then published an updated guideline in 2002, which the ACP recognized as a scientifically valid review of the evidence and background paper. This ACP guideline summarizes the recommendations of the 2002 ACC/AHA updated guideline and underscores the recommendations most likely to be important to physicians seeing patients in the primary care setting. This guideline is the first of 2 that will provide guidance on the management of patients with chronic stable angina. This document will cover diagnosis and risk stratification for symptomatic patients who have not had an acute myocardial infarction or revascularization procedure in the previous 6 months. Sections addressing asymptomatic patients are also included. Asymptomatic refers to patients with known or suspected coronary disease based on history or on electrocardiographic evidence of previous myocardial infarction, coronary angiography, or abnormal results on noninvasive tests. A future guideline will cover pharmacologic therapy and follow-up.     

Stress echocardiography versus myocardial SPECT for risk stratification of patients with coronary artery disease

PURPOSE OF REVIEW: Diagnostic testing using noninvasive imaging has become an integral part of risk stratification in patients with coronary artery disease. It is important to understand the integral strengths and weaknesses between the different modalities of stress testing and to apply accurately the type of test the clinical scenario demands. RECENT FINDINGS: There have been tremendous advances made in the field of cardiac imaging. Both myocardial perfusion imaging and stress echocardiographic techniques continue to evolve and play an important role in the assessment of patients with coronary artery disease. SUMMARY: In this review the authors discuss the relative merits of both stress echocardiography and myocardial single photon emission computed tomographic imaging for diagnosis and risk stratification of patients with coronary artery disease.     

An overview of contemporary nuclear cardiology

Myocardial perfusion single photon emission computed tomography (SPECT) is a widely utilized noninvasive imaging modality for the diagnosis, prognosis, and risk stratification of coronary artery disease. It is clearly superior to the traditional planar technique in terms of imaging contrast and consequent diagnostic and prognostic yield. The strength of SPECT images is largely derived from the three-dimensional, volumetric nature of its image. Thus, this modality permits three-dimensional assessment and quantitation of the perfused myocardium and functional assessment through electrocardiographic gating of the perfusion images.     

Stress myocardial perfusion imaging in the diagnosis and prognosis of women with suspected coronary artery disease

Coronary artery disease is the single largest killer of women in the United States and claims the lives of more than 250,000 women each year. For several decades, there was the misperception that coronary artery disease was a "man's disease." The fact is that women are indeed vulnerable to coronary artery disease; however, they typically develop the disease 10 to 15 years later than men. Once coronary artery disease is evident, women have worse outcomes as compared with men.Therefore, early and accurate diagnosis of coronary artery disease is crucial for reducing heart disease mortality in women. Stress myocardial perfusion imaging using contemporary techniques has been shown to have significant value in the diagnosis and prognosis of coronary artery disease in women. Myocardial perfusion imaging with exercise or pharmacologic stress has been shown to add incremental value to the use of clinical variables or exercise electrocardiogram stress testing alone in the risk stratification of women with an intermediate clinical pretest likelihood of coronary artery disease. This review provides an overview of the role of stress myocardial perfusion imaging in the clinical evaluation of women with suspected coronary artery disease.     

核素心肌灌注显像在糖尿病人群中的应用

核素心肌灌注显像作为一种非侵入性的影像学技术已经广泛应用于冠心病的诊断、危险度分层、预后判断以及疗效的评估中,其临床价值已经得到充分肯定.近年来,随着糖尿病发病率的逐步上升,探讨该技术在糖尿病人群中的应用具有重要的临床价值.     

Value of gated SPECT myocardial perfusion imaging for individual cardiac risk assessment

Myocardial perfusion imaging enables not only accurate diagnosis of disease but also entails prognostic value. Myocardial perfusion SPECT contributes to assessment of future cardiac events independently of other clinical parameters. A normal stress myocardial perfusion scan is associated with a favorable prognosis independent of history, symptoms, and exercise electrocardiography test variables. Cardiac risk and benefit from invasive therapeutic strategies increase in relation to the severity of the abnormality of perfusion and function assessed by gated myocardial perfusion SPECT. Thus, stress myocardial perfusion imaging may serve as a gatekeeper for referral to coronary angiography enabling effective risk stratification in patients with suspected or documented coronary artery disease.     

MRI for the diagnosis of myocardial ischemia and viability

Assessment of myocardial ischemia and viability plays a crucial role in the clinical management of patients with coronary artery disease. Recently, cardiovascular MRI has emerged as an important noninvasive diagnostic modality in the assessment of coronary artery disease. MRI is able to evaluate both myocardial perfusion as well as myocardial contractile reserve. Because of its superior spatial resolution, integration of qualitative and quantitative methodology, and excellent reproducibility, MRI has advantages over conventional noninvasive modalities currently used in the evaluation of myocardial ischemia and viability, and may well emerge as the premier noninvasive technique in the assessment of patients with coronary artery disease. The authors review the rapidly expanding recent literature that has now established cardiovascular MRI (including dobutamine cine MRI and vasodilator perfusion MRI techniques) as an ideal choice in the evaluation of myocardial ischemia and delayed contrast-enhanced MRI and low-dose dobutamine cine MRI for evaluation of viability. Comparisons with more established techniques such as dobutamine stress echocardiography, single photon emission computed tomography perfusion imaging, and positron emission tomography are reviewed.     

Diagnostic and Prognostic Value of Myocardial Perfusion Imaging in Patients with Known or Suspected Stable Coronary Artery Disease

Coronary artery disease is the leading cause of complications and death in the United States and other Western countries, and stress myocardial perfusion study is an important component of the clinical evaluation, stratification, and management. This imaging technique is a well-established modality and has been widely used for the past three decades. New quantitative techniques for the assessment of ventricular function using quantitative gated single-photon emission computed tomography in addition to myocardial perfusion will potentially enhance the role of nuclear cardiology in the management of these patients. This review summarizes the current knowledge of the diagnostic and prognostic uses of stress myocardial perfusion imaging using exercise and pharmacological stress in patients with stable coronary artery disease.     

腺苷负荷心肌灌注显像141例临床分析

目的:腺苷负荷心肌灌注显像(MPI)与冠状动脉造影(CAG)2种检查方法的结果对比分析。方法:对141例患者分别行腺苷负荷MPI及CAG检查,并使用校正的TIMI血流分级(CTFC)方法评价冠状动脉血流速度。对2种方法的检查结果进行比较分析。结果:腺苷负荷MPI阳性的99例患者中,经CAG检查确诊冠心病者52例,冠状动脉慢血流(CSF)者37例,冠状动脉正常者10例。腺苷负荷MPI对冠心病诊断的灵敏度和特异度为92.9%和44.7%;对CSF诊断的灵敏度和特异度为82.2%和75.0%。结论:腺苷负荷MPI阳性者中一部分为冠心病患者,一部分为CSF者,对于腺苷负荷MPI异常的患者需进一步行CAG检查以明确病情。     

Advances in rubidium PET and integrated imaging with CT angiography

The role of rubidium-82 (Rb-82) positron emission tomography (PET) in the evaluation and care of patients with suspected coronary artery disease is evolving in conjunction with advances in PET instrumentation, data analysis, and clinical research. Instrumentation developments such as three-dimensional acquisition, new scintillator materials, and x-ray CT help to improve the quality of Rb-82 images. New approaches to kinetic modeling and software tools for analysis of clinical Rb-82 studies are being developed and evaluated, enabling quantification of absolute myocardial blood flow and flow reserve. Recent clinical research studies are providing new insights into the value of Rb-82 cardiac imaging compared with single photon emission CT myocardial perfusion imaging. Integrated x-ray CT angiography and Rb-82 PET perfusion imaging on hybrid PET/CT systems is an exciting new prospect. Complementary anatomical and functional information on atherosclerosis and ischemia can be provided in a single imaging session for better diagnosis and risk stratification of patients with coronary artery disease.     

The added value of simultaneous myocardial perfusion and left ventricular function

The focus of this review is the advantages of simultaneously assessing myocardial perfusion and left ventricular function. Nuclear cardiology imaging techniques as well as the development of technetium-labeled perfusion tracers now permit combined myocardial-perfusion and left-ventricular function studies at a single testing interval. Radionuclide angiography as well as electrocardiographic-gated images of the perfused myocardium are the two well-established techniques for that purpose with a single injection of a technetium-labeled perfusion tracer. Recent data have demonstrated the impact and clinical role of these studies, when combined, in the diagnosis as well as prognosis and risk stratification of patients with suspected or known coronary artery disease. The addition of functional information to perfusion data has shown to improve the detection of multivessel disease. Most recent data have also demonstrated the ability of these combined measurements to improve the prediction of hard events. It appears that the role of each of these tests may differ, depending on the patient population, particularly in relation to gender and type of stress test performed. Finally, a third area of potential application of these combined techniques would be in the assessment of myocardial viability using pharmacologic stress tests in combination with wall-motion analysis by gated images of the perfused myocardium.     

Myocardial Perfusion Imaging with Cardiac Computed Tomography: State of the Art

Cardiac computed tomography (CCT) has become an important tool for the anatomic assessment of patients with suspected coronary disease. Its diagnostic accuracy for detecting the presence of underlying coronary artery disease and ability to risk stratify patients are well documented. However, the role of CCT for the physiologic assessment of myocardial perfusion during resting and stress conditions is only now emerging. With the addition of myocardial perfusion imaging to coronary imaging, CCT has the potential to assess both coronary anatomy and its functional significance with a single non-invasive test. In this review, we discuss the current state of CCT myocardial perfusion imaging for the detection of myocardial ischemia and myocardial infarction and examine its complementary role to CCT coronary imaging.     

Management of Atrial Fibrillation in 2021: An Updated Comparison of the Current CCS/CHRS,ESC, and AHA/ACC/HRS Guidelines

Given its complexity, the management of atrial fibrillation (AF) has relied increasingly on expert guideline recommendations; however, discrepancies between these professional societies can lead to confusion among practicing clinicians. This article compares the recommendations in the 2019 American Heart Association (AHA)/American College of Cardiology (ACC)/Heart Rhythm Society (HRS), the 2020 European Society of Cardiology (ESC), and the 2020 Canadian Cardiovascular Society/Canadian Heart Rhythm Society (CCS/CHRS) AF guidelines. Although many of the recommendations are fundamentally similar, there are important differences among guidelines; specifically, key differences are present in (1) definitions and classification of AF; (2) the role of opportunistic AF detection; (3) symptom and quality-of-life evaluation; (4) stroke-risk stratification and the indication for oral anticoagulation (OAC) therapy; (5) the role of aspirin in prevention of stroke for patients with AF; (6) the antithrombotic regimens employed in the context of coronary artery disease; (7) the role of OAC, and specifically non-vitamin K direct-acting oral anticoagulants (DOACs), in patients with chronic and end-stage renal disease; (8) the target heart rate for patients treated with a rate-control strategy, along with the medications recommended to achieve the heart-rate target; and (9) the role of catheter ablation as first-line therapy or in patients with heart failure. These differences highlight areas of continuing clinical uncertainty in which there are important needs and opportunities for future investigative work.     

磁共振心肌灌注成像对老年冠心病的诊断价值

目的　探讨磁共振心肌灌注成像对老年冠心病的诊断价值。方法　对临床确诊的 35例冠心病患者 ,利用磁共振心肌灌注成像方法得到心肌灌注时间 -信号强度曲线 ,观察曲线的上升斜率和信号强度的峰值。并同期作了冠脉造影 ,确定心肌异常改变与冠脉病变血管分布相对应关系。结果　 33例经心肌灌注成像有 41个病灶呈低灌注区为心肌缺血 ,其中 5例出现延迟强化为心肌梗死 ,经冠脉造影证实 35例均有不同程度的冠脉狭窄。结论　磁共振心肌灌注成像与冠脉造影检查结果无明显差异 ,具有高度的一致性。而磁共振心肌灌注成像是一种无创性测定心肌血流的检查方法 ,为及时诊断及恰当治疗冠心病提供可靠的依据     

Myocardial perfusion imaging in ischemic heart disease anno 1990

The field of radionuclide myocardial perfusion imaging is in a rapid state of change. Stress-rest myocardial imaging is important not only for the detection of coronary artery disease but also for prognostic stratification of patients. In particular, assessment of myocardial viability in patients with left ventricular dysfunction is a recent focus of investigation. Single-photon emission computed tomography has become widely accepted as the preferred (albeit challenging) imaging modality for myocardial perfusion imaging. Silent myocardial ischemia and its clinical significance continues to be an intriguing aspect of the clinical manifestation of coronary artery disease. Myocardial perfusion imaging is an invaluable independent method to unravel this problem. Dipyridamole was approved for pharmacologic vasodilation in conjunction with myocardial perfusion imaging. At the same time, direct infusion of adenosine was proposed as an alternative method of effecting vasodilatory stress. In 1990, several new technetium-99m-labeled myocardial perfusion imaging agents have been introduced (teboroxime and hexakis-2-methoxyisobutyl-isonitrile [sestaMIBI]) that may have a profound impact on imaging techniques and applications of myocardial perfusion imaging.     

Magnetic resonance imaging in the assessment of coronary artery disease

Magnetic resonance imaging (MRI) is gaining importance in cardiology as the noninvasive test of choice for patients with a multitude of cardiovascular problems. Recently, cardiovascular MRI has emerged as an important noninvasive diagnostic modality in the assessment of coronary artery disease. Because of its superior spatial resolution, integration of qualitative and quantitative methodology, and excellent reproducibility, MRI has advantages over conventional noninvasive modalities currently used in the evaluation of coronary artery disease. This article reviews the rapidly expanding recent literature that has now established cardiovascular MRI as an ideal choice in the evaluation of myocardial ischemia (including dobutamine cine MRI and vasodilator perfusion MRI techniques). We further discuss the role of delayed contrast-enhanced MRI and low-dose dobutamine cine MRI for evaluation of myocardial viability. Comparisons with more established techniques, such as dobutamine stress echocardiography, single-photon emission computed tomography perfusion imaging, and positron emission tomography, are reviewed.     

Prediction of single versus multivessel disease following myocardial infarction using 201thallium scintigraphy and electrocardiographic stress testing

We evaluated 50 patients who suffered a single myocardial infarction with graded electrocardiographic stress testing, 201thallium myocardial perfusion imaging and coronary angiography to assess the role of noninvasive indices as predictors of single versus multivessel coronary artery disease. Multivessel involvement was defined angiographically as the presence of two or more major coronary arteries with at least a 70% intraluminal diameter narrowing. Multivessel disease was defined scintigraphically as the presence of stress and/or redistribution perfusion defects in the distribution of more than one coronary artery. The results of stress electrocardiography were not useful in differentiating patients with single (9/16 positive) versus multivessel (22/34 positive) disease. The degree of exercise-induced ST-segment depression was also not helpful. Stress 201thallium imaging did offer limited additional information with correct predictions of multivessel disease in 21 of 26 patients. Predictions of single-vessel disease were accurate in 11 of 24 patients. Eleven of these 13 incorrect predictions of single-vessel disease were due to the relative insensitivity of the thallium stress image to perceive defect in the anterior wall when the left anterior descending artery had significant obstruction at catheterization. Further refinements of stress perfusion imaging are needed before this method can be used to reliably separate patients with single and multivessel disease after myocardial infarction.