Continuing education assessment of myocardial viability in patients with heart failure arend f. Noninvasive assessment of myocardial viability nejm. Assessment of left ventricular viability techniques for assessing myocardial viability depend on the measurement of a specific characteristic of viable myocytes such as cell membrane integrity, preserved metabolism, mitochondria integrity, and preserved contractile reserve. As such, assessment of myocardial viability is accomplished by comparing fdg uptake with the regional distribution of myocardial perfusion, determined either by pet or spect. N2 the prevalence of left ventricular lv dysfunction and resultant congestive heart failure is increasing. The use of mce for viability assessment is based on the principle that microvascular integrity is a fundamental prerequisite for myocardial viability.
Imaging modalities have become frontline methods in the assessment of viable myocardial tissue, with the aim to stratify patients into optimal. Schinkel1, don poldermans1, abdou elhendy2, and jeroen j. Evaluation of myocardial viability radcliffecardiology. Both 15o water and 82rb chloride may also provide information on both blood flow and viability.
The following two protocols are optimized for viability detection. Second, in comparative studies with thallium reinjection and pet imaging with fdg, most myocardial segments that were identified as viable by reinjection had metabolic evidence of myocardial viability. A nuclear medicine thallium viability scan is a test used to evaluate the blood flow to the heart. F18 fdg imaging provides the unique ability to assess metabolic activity in an area of hypoperfusion. Detection of myocardial viability european society of. Objectives this study pools data from published series examining late survival with revascularization versus medical therapy after myocardial viability testing in patients with severe coronary artery disease cad and left ventricular lv dysfunction. Spect underestimates the extent of myocardial viability. To define viability with pet, assessment of perfusion must also be made.
Listing a study does not mean it has been evaluated by the u. Viable myocardium in the setting of myocardial contractile dysfunction represents hibernating or stunned myocardium. In current clinical practice, myocardial viability is evaluated with stress echocardiography and nuclear methods. Myocardial metabolism imaging with pet identifies preserved metabolic activity in dysfunctional and hypoperfused myocardial regions. Assessment of myocardial viability in patients with heart. Imaging modalities have become frontline methods in the assessment of viable myocardial tissue, with the aim to stratify patients into optimal treatment pathways. The concept of hibernating myocardium originated from observations in the 1970s that the myocardial dysfunction seen in patients with chronic coronary artery disease cad was not always permanent. Pdf coronary artery disease cad is the most prevalent and single most common cause of morbidity and mortality1 with the resulting left ventricular. This observation emphasizes that it is clinically relevant to search for viability in patients with chronic ischemic cardiomyopathy. Practical implications of myocardial viability studies scielo.
Assessment of myocardial viability with thallium201 and. Abstract background the role of assessment of myocardial viability in identifying patients with ischemic cardiomyopathy who might benefit from surgical revascularization remains controversial. The watershed examination to decide on best treatment strategy is the assessment of myocardial viability. Thanks to its intrinsic characteristics and to the delayedenhancement technique demri, mri has recently emerged as the only noninvasive modality able to provide a threedimensional 3d evaluation of cardiac viability with a.
Positron emission tomography for the assessment of myocardial viability ohtas 2010. The current document is an update of an earlier version of pet guidelines that was developed by the american society of nuclear cardiology. The identification of myocardial viability in patients with coronary artery disease and left ventricular dysfunction lvd has important clinical and prognostic. Multiple observational studies have reported that viability imaging will be instrumental in such patients. In patients with coronary artery disease cad, left ventricular lv function remains one of the most robust prognostic determinants of survival 46, also impacting total hospital separations and many defined. The 99mtc isonitriles and 99mtctetrofosmin seem to be the most promising of this group of agents for determining myocardial viability. Noninvasive imaging in detecting myocardial viability. Positron emission tomography for the assessment of.
Detection of myocardial viability in the prediction of improvement in left ventricular function after successful coronary revascularization by using the dobutamine stress echocardiography and quantitative spect restredistributionreinjection 201 t1 imaging after dipyridamole infusion. Assessment of myocardial viability in patients before. Myocardial viability detected with spect perfusion imaging. Mri method for assessing myocardial viability inventors thomas grist, orhan unal since its founding in 1925 as the patenting and licensing organization for the university of wisconsinmadison, warf has been working with business and industry to transform university research into products that benefit society. Min, md facc president society of cardiovascular computed tomographypresident, society of cardiovascular computed tomography associate professor of medicine, ucla school of medicine associate professor of medicine and imaging cedarsassociate professor of medicine and imaging, cedarssinai medical center. Survival is worse as the left ventricular ejection fraction decreases, the extent of coronary artery disease increases, and the age of the patient increases. The usefulness of restredistribution thallium imaging in identifying myocardial viability was further supported by ragosta and coworkers, who studied 21 patients with left ventricular dysfunction mean ejection fraction 27% who subsequently underwent bypass surgery. After a heart attack myocardial infarction, some of the heart muscle may be permanently damaged or scarred. Selection of patients for viability study and revascularization article pdf available in journal of tehran university heart center 41 march 2009 with 124. Mri evaluation of myocardial viability mayo clinic. For clinical purposes, at present, there are four different ways of using mr for the assessment of myocardial viability. It has been shown that, in such segments, peak contrast intensity reflects microvascular density and is inversely related to collagen content i.
Positron emission tomography for the assessment of myocardial. Once this occurs, the area affected will cease to function properly. For imaging viability, singleslice 2d mri techniques are widely used. Ischaemic left ventricular lv dysfunction can arise from myocardial stunning, hibernation, or necrosis. The fact that revascularization with coronary artery bypass grafting cabg could result in the recovery. Noninvasive imaging can help identify viable segments of myocardium that have greater likelihood of improving functionally when an adequate blood supply is. After a myocardial infarction, the myocardium will usually demonstrate one of 5 pathophysiologies. Multimodality imaging in the assessment of myocardial. This paper summarizes the pathophysiology, methods, and impact of detection of myocardial viability, concentrating on recent advances in such methods. Assessment of myocardial viability with 3d mri at 3 t. Multicenter myocardial viability trial the safety and scientific validity of this study is the responsibility of the study sponsor and investigators.
The fact that revascularization with coronary artery bypass grafting cabg could result in the recovery of. Probably the most established and bestdocumented singleslice technique in the literature is an inversion recovery gradientrecalled echo gre technique for the detection of myocardial in. Viability of myocardial tissue is the central principal which underpins reperfusion therapies, whether in the acute phase following myocardial infarction or in chronic ischemiamediated lv dysfunction. Investigations in humans have used positron emission tomographic metabolic and myocardial blood flow measurements, assessment of gene. Patients with this condition are at high risk for cardiac death and usually have signi. Assessment of myocardial viability and protection during cabg solomon aronson, m. Nov 21, 2012 prevalence of myocardial viability as detected by positron emissiontomography in patients with ischemic cardiomyopathy circulation volume 9922, 8 june 1999, pp 29212926methods. Recent publications have demonstrated the accuracy of cardiac magnetic resonance imaging cardiac mri in assessing myocardial viability, together with.
Assessment of cardiac muscle using imaging methods enables the localization, quantification of viability in dysfunctional myocardium and possibility of anatomical. The assessment of myocardial viability in patients with left ventricular dysfunction has a great impact on the decision making process regarding therapy for such patients, as it allows the identification of those who will benefit the most from a revascularization procedure, be it through surgical approach or through percutaneous angioplasty. Nuclear medicine imaging of myocardial viability clinical gate. Initial studies, although favorable, lacked sufficient power and sample size to provide conclusive outcomes of viability. In vivo quantitative assessment of myocardial structure. Importantly, available data are inconclusive regarding the usefulness of myocardial viability tests for the decision concerning revascularization in patients with left ventricular lv dysfunction and cad 1. In recent years, new advances have improved methods of detecting myocardial viability. Pet is considered the gold standard to assess myocardial viability. Other noninvasive modalities, such as stress echocardiography, also facilitate the assessment of myocardial viability, but there are advantages and disadvantages compared with the nuclear techniques. C assessment of myocardial viability in patients with heart failure arend f.
Myocardial viability dead or alive is not the question. Prevalence of myocardial viability as detected by positron emissiontomography in patients with ischemic cardiomyopathy circulation volume 9922, 8 june 1999, pp 29212926methods. Background previous observational studies have suggested survival benefit in such patients if they are revascularized when myocardial. As such, assessment of myocardial viability is accomplished by comparing fdg uptake with the regional distribution of myocardial perfusion, determined either by. Fatty acids pet, uptake of ffluorodeoxyglucose fdg is a marker of glucose metabolism blood flow n h3, tc 99msestamibi, tc 99mtetrofosmin contractyle reserve low dose dobutamine rwm analysis morphology mr hyperenhancement. Pdf assessment of myocardial viability in patients with. Spect for viability assessment when to use what myocardial viability, but th eir myocardial uptake is flow dependent. Thallium201 uptake by myocytes is also a reflection of regional perfusion required for delivery of tracer to the myocyte and viability. About 35% of nonreversible spect defects are hibernating myocardium w ith severe reduction of blood flow. For assessment of myocardial perfusion, tracers include oxygen15 15o water, nitrogen n ammonia, and rubidium82 82rb chloride. Background previous observational studies have suggested survival benefit in such patients if they are revascularized when myocardial viability. The assessment of myocardial viability has been used to identify patients with coronary artery disease and left ventricular dysfunction in whom coronaryartery bypass grafting cabg will provide a survival benefit. Myocardial uptake of 99mtcsestamibi is proportional to the regional blood. Eike nagel, md, phd, andreas schuster, md london, united kingdom when talking about viabilityor better.
Nuclear imaging appears to require fewer viable cells for detection, resulting in a higher sensitivity but a lower specificity than stress. Bax3 1thoraxcenter, department of cardiology, erasmus medical center, rotterdam, the netherlands. Such dysfunction can be improved by restoring the perfusion in presence of chronic ischemia in the case of hibernating myocardium, or can improve. Pathophysiology and mechanism of myocardial viability. Nuclear medicine assessment of myocardial viability. Myocardial viability assessment was provided via dse n, or spect n 321, or both n 150. The assessment of the distinct states of noncontractile myocardium in patients with coronary artery disease cad and left ventricular lv dysfunction is clinically relevant, both prognostically and therapeutically 1, 2, 3, 4.
The goal of this work is to provide a practical guide to the use of the highspeed quantum fx microct system for comprehensive determination of myocardial global and regional function along with assessment of myocardial perfusion, metabolism and viability in healthy mice and in a cardiac ischemia mouse model induced by permanent occlusion of. Assessment of myocardial viability albert einstein. Myocardial viability and survival in ischemic left. The recommended approach to assess myocardial viability begins with either functional images in the form of dse and dobutamine stress cmr imaging or perfusion images in the form of radionuclide myocardial perfusion imaging spect and legcmr, depending on availability and local expertise. Therefore, these data also indicate the poor prognosis for patients who have viable myocardium but who do not receive adequate revascularization. Other parts of the heart may be injured, but not permanently scarred. Hibernating myocardium has depressed myocardial contractility at rest due to persistently impaired coronary blood flow with function that can be partially or completely restored by improving coronary blood flow, by providing inotropic stimulation or by. The concept of myocardial hibernation was introduced by rahimtoola to describe a condition of chronic sustained abnormal contraction attributable to chronic underperfusion in patients who have coronary artery disease and in whom revascularization causes the recovery of lv function. Multicenter myocardial viability trial full text view. Of the viability subgroup, 298 participants were randomly assigned to receive medical therapy plus surgical revascularisation cardiac bypass and 303 received solitary medical management. Myocardial viability in dysfunctional lv segments is dependent upon maintenancepresence of an intact microcirculation.
Assessment of myocardial viability membrane integrity. Bergmann, md, phd the prevalence of left ventricular lv dysfunction and resultant congestive heart failure is increasing. Myocardial viability testing and impact of revascularization. Assessment of myocardial viability in patients with heart failure. Ischaemic heart disease ihd is the leading cause of morbidity and mortality in western society, with an overrepresentation in the primary healthcare burden. Over the years, echocardiography has been used exten sively for the assessment of myocardial viability.
However, the efficacy of this approach is uncertain. Assessment of myocardial viability albert einstein college. Myocardial contrast echocardiography mce senior et al 2009 illustrated the accuracy of mce for the prediction of myocardial viability, demonstrating a mean sensitivity of 85% and specificity of 70%12. The presence of glucose activity by fdg imaging provides evidence of viability. Multimodality imaging in the assessment of myocardial viability. Stunning, hibernation, and assessment of myocardial viability. The myocardial uptake of thallium201 is a sarcolemmal membrane nak atpasedependent active process requiring cell membrane integrity, and is therefore indicative of myocardial viability. The measurement of enddiastolic wall thickness, the evaluation of contractile reserve during inotropic stimuli, the evaluation of regional myocardial perfusion, and the contrast based depiction of scar tissue. Because of high mortality rate and increasing prevalence of heart failure and the need to tailor therapy to the etiology and stage of the condition, testing of patients with heart failure will become increasingly common. Gated technetium99 m sestamibi for simultaneous assessment of stress myocardial perfusion, postexercise regional ventricular function and myocardial viability.
Asnc imaging guidelines for nuclear cardiology procedures. Clinically, in different patients, similar degrees of lv dysfunction may be associated with large differences in the amount of viable myocardium, and even extreme. Positron emission tomography for myocardial viability. Myocardial viability assessment is an important part of cardiac pet to assist physicians to decide upon the best surgical or medical procedures. Viability studies hamilton cardiology associates new. Mce can predict functional recovery following acute mi and is comparable to cmr imaging in this regard.