Imaging of ischemic heart disease

Abstract

Despite advances in the understanding and treatment of ischemic cardiomyopathy, characterized by extensive coronary artery disease and left ventricular (LV) dysfunction, the prognosis remains poor with only a 50-60% 5-year survival rate. The composition of atherosclerotic lesions is currently regarded as being more important than the degree of stenosis in determining acute events. If imaging techniques could distinguish vulnerable from stable plaques, then high-risk patient subgroups could be identified. Another important concept is that LV dysfunction may be the result of either scarring due to necrosis or to the presence of myocardial hibernation, in which there is sufficient blood flow to sustain viable myocytes, but insufficient to maintain systolic contraction. This concept of myocardial viability is critical for making optimal clinical management decisions. This review describes how noninvasive imaging methods can be used to distinguish regions of irreversibly injured myocardium from viable but hibernating segments. Technical advances in CT and MR have made imaging of the beating heart possible. Considerable clinical progress has already been made and further cardiac applications are expected. Radiologists therefore have new opportunities for involvement in cardiac imaging but must recognize the political implications as well as the diagnostic potential of these modalities not only for the heart, but also for the whole vascular system. This review focuses on imaging myocardial injury. It compares state-of-the-art CT and MR with more established yet contemporary echocardiography and nuclear scintigraphy.

The Role of Cardiac MRI In Coronary Heart Disease Management

“…Myocardial injury either acute or chronic, localized to the endocardium, or transmural. Both clinical and radiographic presentation is different between acute and chronic (14) . In chronic IHD, the pathological atherosclerotic process starts early in life during the second and third decades (14) and sometimes remain undetected until causing first exercise-induced, following by rest symptoms.…”

“…Both clinical and radiographic presentation is different between acute and chronic (14) . In chronic IHD, the pathological atherosclerotic process starts early in life during the second and third decades (14) and sometimes remain undetected until causing first exercise-induced, following by rest symptoms. The effect of prior myocardial infarction and its pathophysiologic consequences characterize the radiographic findings of these patients.…”

“…All these events constitute the term acute coronary syndromes (ACS). It covers a spectrum ranging from sudden death to unstable angina (14) . Myocardial injury either acute or chronic, localized to the endocardium, or transmural.…”

“…The effect of prior myocardial infarction and its pathophysiologic consequences characterize the radiographic findings of these patients. The imaging study of patients with IHD is a good tool providing clinically significant information regarding the extent and severity of coronary artery pathology, if there are any chronic changes, what is the effect of superimposed acute ischemic events on this subclinical process (14) .…”

“…Left ventricular configuration can be identified in plain PA film of some patients with left ventricular ischemia (15) . This includes an increase in the curvature of the left ventricular contour and aortic arch segments of the left heart border, between which are sandwiched normal left atrial appendage and main pulmonary artery segments, this can help to identify patients with subclinical heart disease (14) . Signs of elevated pulmonary venous pressure are found in some patients with IHD.…”