Imaging of the Failing Heart (original) (raw)

The role of myocardial viability in contemporary cardiac practice

Heart failure reviews, 2017

Ischemic heart disease (IHD) remains the single most common cause of death worldwide. Ischemic cardiomyopathy is a major sequel of coronary artery disease. The economic health burden of IHD is substantial. In patients with old myocardial infarction (OMI), the extent of viable myocardium (VM) directly affects the short- and long-term outcome. There is a considerable collection of observational data showing substantial improvement in patients with significant left ventricular dysfunction when the need for revascularization is guided by preoperative assessment of viability and hibernation. However, a major challenge for present cardiovascular imaging is to identify better ways to assess viable but inadequately perfused myocardium and thus optimize selection of patients for coronary revascularization. Several non-invasive techniques have been developed to detect signs of viability. Hence, our aim is to provide the reader a state-of-the art review for the assessment of myocardial viability.

The complex relation between myocardial viability and functional recovery in chronic left ventricular dysfunction

The American Journal of Cardiology, 1998

Preserved myocardial viability and recurrent symptomatic ischemia are the most widely accepted criteria indicating that coronary revascularization should take place in patients with postischemic left ventricular dysfunction. However, the presence of viable myocardium within the infarct zone does not necessarily imply recovery of function after coronary revascularization. The complex relation between the extent of transmural necrosis and the degree of residual perfusion within the infarct area plays an important role. However, independently of functional recovery, cell viability may have important clinical implications, since it may improve long-term prognosis by attenuating left ventricular remodeling processes. Several different methods are used to detect hibernating myocardium. Mounting evidence suggests that thallium-201 scintigraphy is most sensitive in identifying tissue viability, whereas dobutamine echocardiography is most specific in predicting functional recovery after revascularization. In between, myocardial contrast echocardiography is the only technique able to evaluate the microvascular integrity that is a condition sine qua non for both cell viability and later functional recovery. Combined information derived from these 3 different approaches might be considered as the best way to understand how the combination of contractile, viable but noncontractile, and dead tissue affect resultant function and prognosis. ᮊ1998 by Excerpta Medica, Inc.

Viability Testing Revascularization in Severe Left Ventricular Dysfunction: The Role of

2010

Revascularization is a treatment option for moderate-to-severe ischemic cardiomyopathy. Limitations of the current literature, lack of completed randomized trials, and higher periprocedural risks create significant uncertainty about the optimal treatment strategy. This review focuses on the available literature describing the effect of revascularization on outcome and the role of noninvasive viability testing. It attempts to identify a subset of patients likely to benefit from therapy. (J Am Coll Cardiol 2005;46:567-74) are needed, are ongoing, and, potentially, can better define the role of noninvasive viability testing and the value of revascularization over medical therapy for LV systolic dysfunction and HF.

Review: Do We Still Need a Viability Study before Considering Revascularization in Patient with Stable Coronary Artery Disease and Significant Left Ventricular Systolic Dysfunction?

International Journal of Clinical Medicine, 2014

Patients with ischemic cardiomyopathy constitute a heterogeneous group of patients with an extremely complex condition in which many factors play an important prognostic role. So it is difficult and probably unrealistic to expect that a single feature like presence of viable myocardium would provide an unequivocal answer to a critical question of revasculrization or not for all patients. Opposite to the hopes of investigators and physicians involved in the care of these patients, the findings of prospective studies with the use of different viability testing methods did not help in the decision-making process regarding CABG in ischemic cardiomyopathy. Instead, they left us with the same dilemma. The implication of most of these trials is that in patients with CAD and significant LV dysfunction, assessment of myocardial viability does not identify patients who will have the greatest survival benefit from adding CABG to aggressive medical therapy. In the clinical practice, these observations remind physicians to consider the multiplicity of factors involved in the decision-making process for patients with such a complex disease.

Myocardial Viability Testing in the Management of Ischemic Heart Failure

Life

Although major advances have occurred lately in medical therapy, ischemic heart failure remains an important cause of death and disability. Viable myocardium represents a cause of reversible ischemic left ventricular dysfunction. Coronary revascularization may improve left ventricular function and prognosis in patients with viable myocardium. Although patients with impaired left ventricular function and multi-vessel coronary artery disease benefit the most from revascularization, they are at high risk of complications related to revascularization procedure. An important element in selecting the patients for myocardial revascularization is the presence of the viable myocardium. Multiple imaging modalities can assess myocardial viability and predict functional improvement after revascularization, with dobutamine stress echocardiography, nuclear imaging tests and magnetic resonance imaging being the most frequently used. However, the role of myocardial viability testing in the manageme...

Myocardial viability: what we knew and what is new

Cardiology research and practice, 2012

Some patients with chronic ischemic left ventricular dysfunction have shown significant improvements of contractility with favorable long-term prognosis after revascularization. Several imaging techniques are available for the assessment of viable myocardium, based on the detection of preserved perfusion, preserved glucose metabolism, intact cell membrane and mitochondria, and presence of contractile reserve. Nuclear cardiology techniques, dobutamine echocardiography and positron emission tomography are used to assess myocardial viability. In recent years, new advances have improved methods of detecting myocardial viability. This paper summarizes the pathophysiology, methods, and impact of detection of myocardial viability, concentrating on recent advances in such methods. We reviewed the literature using search engines MIDLINE, SCOUPS, and EMBASE from 1988 to February 2012. We used key words: myocardial viability, hibernation, stunning, and ischemic cardiomyopathy. Recent studies showed that the presence of viable myocardium was associated with a greater likelihood of survival in patients with coronary artery disease and LV dysfunction, but the assessment of myocardial viability did not identify patients with survival benefit from revascularization, as compared with medical therapy alone. This topic is still debatable and needs more evidence.