Assessment of myocardial viability using singlephoton. As such, assessment of myocardial viability is accomplished by comparing fdg uptake with the regional distribution of myocardial perfusion, determined either by. Future directions include use of magnetic resonance imaging, as well as larger, multicenter trials of radionuclide techniques. Spect underestimates the extent of myocardial viability. Assessment of left ventricular myocardial viability by 3.
Cardiac magnetic resonance and myocardial viability. Of the viability subgroup, 298 participants were randomly assigned to receive medical therapy plus surgical revascularisation cardiac bypass and 303 received solitary medical management. Late redistribution imaging 24 h after exercise has been proposed to overcome this limitation of thallium stress imaging. However, because of poor count density the image quality on these studies is often suboptimal. Myocardial contrast echocardiography mce, which utilizes microbubbles can assess the integrity of the microvasculature, which sustains myocardial viability in real time and can hence rapidly provide information on myocardial viability at the bedside without ionizing radiation. Assessment of left ventricular myocardial viability by 3dimensional speckletracking echocardiography in patients with myocardial infarction t has been well recognized that coronary artery disease is an active contributor to the rise in the prevalence of myocardial ischemia or myocardial infarction mi and associated mortality and morbidity. Assessment of myocardial viability is often needed in patients with chest pain and reduced ejection fraction. Objectives comparison of myocardial tissuevelocity imaging tvi and speckletracking echocardiography ste for prediction of viability at dobutamine echocardiography dbe. Assessment of myocardial viability in patients with myocardial infarction using twentyfour hour thallium201 late redistribution imaging. Bergmann, md, phd the prevalence of left ventricular lv dysfunction and resultant congestive heart failure is increasing. 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 use of mce for viability assessment is based on the principle that microvascular integrity is a fundamental prerequisite for myocardial viability.
Multiple imaging techniques have been developed to assess viable and nonviable myocardium by evaluating perfusion, cell membrane integrity, mitochondria, glucose. Cmr assessment of myocardial viability relies primarily on regional contractile function and delayed gadolinium enhancement to determine extent of transmural scar. Assessment of myocardial viability in patients before. Assessment of myocardial viability with 3d mri at 3 t kerstin u. Just as musicians influence each other, and painters use techniques created by past masters, and. Assessment of myocardial viability membrane integrity. Myocardial metabolism imaging with pet identifies preserved metabolic activity in dysfunctional and hypoperfused myocardial regions. Chapter 17 assessment of myocardial viability blood supply may then occur as a secondary event. Assessment of myocardial viability in patients with heart failure. Assessment of myocardial viability by p31mrspectroscopy.
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. Thallium201 for assessment of myocardial viability. With echocardiography, myocardial viability is commonly assessed using measures of left ventricular lv wall thickness or myocardial contractile reserve. Bauner 1, olaf muehling 2, daniel theisen 1, carmel hayes 3, bernd j. Magnetic resonance imaging of delayed myocardial enhancement using extracellular contrast agents shows an excellent correlation with the extent of acute and chronic myocardial infarction mi, allowing prediction of functional recovery. Exposure to published, written works has greatly influenced his writing, as other writers rhythm, flow and observed style of writing, always affect your work. Imaging modalities have become frontline methods in the assessment of viable myocardial tissue, with the aim to stratify patients into optimal. Bax3 1thoraxcenter, department of cardiology, erasmus medical center, rotterdam, the netherlands. The presence of glucose activity by fdg imaging provides evidence of viability.
In most cases, the current standard for viability is the recovery of function measured by left ventricular lv wall motion and the metabolic activity measured by positron emission tomography pet with the uptake of the. Effect of myocardial viability assessed by cardiac. Among other imaging modalities proven to be useful in the assessment of myocardial viability, singlephoton emission computed tomography spect instrumentation and expertise continue to be the most widely available to the practicing physicians. Although the exact role of preoperative viability testing remains controversial, many physicians continue to think that clinical decision making in highrisk patients warrants assessment of myocardial viability and the probable myocardial response to revascularization. Myocardial viability assessment using nuclear imaging. However limitations to most of the studies included functional cardiac mri studies that assess myocardial viability and perfusion have had small sample sizes. Cmr is presently one of the major imaging modalities for noninvasive assessment of myocardial viability. May 29, 2016 myocardial viability assessment was provided via dse n, or spect n 321, or both n 150. Pathophysiology of myocardial ischemia and viability imbalance between oxygen supply and demand results in myocardial ischemia. Assessment of myocardial viability in reperfused acute. The primary goal of myocardial viability assessment in ischemic cardiomyopathy is to predict the likelihood of contractile recovery of dysfunctional myocardium following medical therapy and revascularization. About 35% of nonreversible spect defects are hibernating myocardium w ith severe reduction of blood flow. Improvement in systolic function has been accepted as the reference standard for the assessment of myocardial viability, as one of the therapeutic goals of revascularization, and as the mechanism. Interpretation of cardiac pet myocardial viability studies.
Pdf myocardial viability assessment using nuclear imaging. Computed tomography assessment of myocardial perfusion. Late gadolinium enhancement imaging in assessment of. Myocardial viability and survival in ischemic left. Therefore, these data also indicate the poor prognosis for patients who have viable myocardium but who do not receive adequate revascularization. Assessment of myocardial perfusion using contrast echocardiography and the novel techniques of strain, strain rate imaging, and 3d echocardiography are currently under investigation. Both 15o water and 82rb chloride may also provide information on both blood flow and viability. Myocardial viability assessment was provided via dse n, or spect n 321, or both n 150.
For assessment of myocardial perfusion, tracers include oxygen15 15o water, nitrogen n ammonia, and rubidium82 82rb chloride. Revascularization improves prognosis in these highrisk patients who have evidence of viability. Noninvasive assessment of myocardial viability may guide patient management. Stunning, hibernation, and assessment of myocardial viability.
Current studies underline the importance and the evolution of several techniques and methods used in the evaluation of myocardial viability. Recent findings we discuss the value of mce to predict. Diagnostic value of 18ffdg pet in the assessment of. Multimodality imaging in the assessment of myocardial. Cardiac magnetic resonance cmr imaging can be used to assess myocardial viability. Magnetic resonance imaging mri is well established for the assessment of myocardial viability.
Assessment of myocardial viability in patients with heart. Practical implications of myocardial viability studies ncbi. Fdg pet acquisition parameters are described in table 3. Viability, cardiovascular magnetic resonance imaging, late contrast enhancement, dobutamine, inotropic reserve, wall thickness, high energy phosphates. Assessment of myocardial viability by cardiovascular magnetic. Ste overcomes these but requires evaluation for prediction of viability. The identification of myocardial viability in patients with coronary artery disease and left ventricular dysfunction lvd has important clinical and prognostic. Preserved myocardial wall thickness of more than 5. Thallium201 uptake by myocytes is also a reflection of regional perfusion required for delivery of tracer to the myocyte and viability.
Assessment of myocardial viability with 15owater pet. Assessment of myocardial viability by cardiovascular. 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. F18 fdg imaging provides the unique ability to assess metabolic activity in an area of hypoperfusion. Contrast and stress echocardiography are important clinical tools for the assessment of myocardial viability. However, the observational studies by rahimtoola 14 indicated that many patients with left ventricular lv dysfunction exhibited improvement of function after revascularisation. Because myocardial perfusion is a prerequisite for myocardial viability, myocardial contrast echocardiography has been used to assess myocardial viability. Nuclear medicine imaging of myocardial viability clinical gate. Assessment of myocardial viability by thallium201 springerlink.
Background use of tvibased strain imaging during dbe may facilitate the prediction of myocardial viability but has technical limitations. Multimodality imaging in the assessment of myocardial viability. This central role of myocardial viability assessment was supported by observational studies and metaanalyses showing that after revascularization patients with. Myocardial viability and longterm outcomes in ischemic.
Assessment of myocardial viability with 3d mri at 3 t. Pdf coronary artery disease cad is the most prevalent and single most common cause of morbidity and mortality1 with the resulting left ventricular. In the clinical setting, a number of techniques key words. Stress echocardiography introduction echocardiography has been routinely used in the assessment of myocardial viability. We evaluated the performance of reduced resting mbf, perfusable tissue fraction ptf, and perfusable tissue index pti in the assessment of myocardial viability in a pig model of myocardial infarction mi. Assessment of myocardial viability has been a challenge for revascularisation therapeutics in determining the effectiveness of an intervention and patient prognosis. Assessment of myocardial viability linkedin slideshare. By continuing to use our website, you are agreeing to our use of cookies. 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.
Over the years, echocardiography has been used exten sively for the assessment of myocardial viability. Heart failure is a common cardiac diagnosis and the prevalence is increasing, with a prediction of more than 8 million affected adults in the united states by 2030. Pathophysiology of myocardial ischemia and viability imbalance between oxygen supply and demand results in myocardial. Pdf assessment of myocardial viability in patients with. Redistribution thallium201 imaging 2 to 4 h after exercise may be incomplete and therefore may be inadequate to fully assess myocardial variability.
Assessment of myocardial viability using coronary zero flow. For a better assessment of ischemic heart diseases, myocardial viability should be quantified. To investigate the relation between coronary flow reserve cfr, coronary zero flow pressure pzf, and residual myocardial viability in patients with acute myocardial infarction. Schinkel1, don poldermans1, abdou elhendy2, and jeroen j. Assessment of myocardial viability by myocardial contrast ec. Multiple imaging techniques have been developed to assess viable and nonviable myocardium by evaluating perfusion, cell membrane integrity. Whether in the setting of acute or chronic ischemia, dysfunctional myocardium may be viable and maintain the potential for functional recovery. Myocardial viability, making writing skills better. Spect for viability assessment when to use what myocardial viability, but th eir myocardial uptake is flow dependent. At present, we lack controlled prospective randomized studies, but indications exist from retrospective studies that patients who undergo a preoperative assessment of viability have better inhospital and 1year outcomes when a viability test is added to clinical and angiographic data. An end diastolic wall thickness of postsystolic thickening at these segments suggests either myocardial viability or ischaemia. Myocardial viability assessment is an important part of cardiac pet to assist physicians to decide upon the best surgical or medical procedures. Continuing education assessment of myocardial viability in patients with heart failure arend f.
Assessment of myocardial viability with thallium201 and. Myocardial viability assessment by cardiac magnetic. The increasing population of patients with lv dysfunction, and the increased benefit afforded by newer therapies, will make assessment of myocardial viability even more essential for proper patient management. Evaluation of myocardial viability radcliffecardiology. Functional cardiac magnetic resonance imaging mri in the. Simultaneous assessment of myocardial viability and function for the detection of hibernating myocardium using ecggated 99 tc mtetrofosmin emission tomography. A comparison with 201 t1 emission tomography combined with cine magnetic resonance imaging. The first descriptions of what would today be recognized as viable myocardium appeared in the 1970s, when it was observed that ventricular dysfunction reverted after revascularization in some patients with antecedents of acute myocardial infarction ami. Myocardial viability detected with spect perfusion imaging.
Positron emission tomography pet is a unique modality that evaluates myocardial viability via assessing the tissues metabolic and perfusion properties. Patients with this condition are at high risk for cardiac death and usually have signi. To define viability with pet, assessment of perfusion must also be made. It has been shown that the contrast echocardiography parameters of myocardial perfusion correlate positively with microvascular density and capillary area and inversely with the extent of. Assessment of cardiac muscle using imaging methods enables the localization, quantification of viability in dysfunctional myocardium and possibility of anatomical. There is some evidence of comparable or better performance of functional cardiac mri for the assessment of myocardial viability and perfusion compared with other imaging techniques. Pdf assessment of myocardial viability using single. Multiple imaging modalities exist for differentiating viable myocardium from scar in territories with contractile dysfunction. Nuclear medicine gives reliable information on regional perfusion, metabolism and cell membrane. The mainstay of metabolic imaging relies on glucose metabolism using 18 fluorodeoxyglucose, a radiolabeled glucose analog. In the current era of revascularization surgery and interventional cardiology, the assessment of myocardial viability has become an integral component of the diagnostic evaluation of patients with coronary artery disease cad and depressed left ventricular lv function. Therefore, while several clinical and laboratory parameters including anginal symptoms, absence of q waves on the electrocardiogram, and regional hypokinesis as opposed to akinesis on echocardiography indicate the presence of some viability, a systematic assessment of the degree and extent of viability by myocardial imaging is generally thought to be helpful for management planning and prognostication. Background 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 wil.
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