MRI of left ventricular function
ABSTRACT Cardiac magnetic resonance imaging (CMR) is widely recognized as the most accurate noninvasive imaging modality for the assessment of left ventricular (LV) function. By use of state-of-the-art magnetic resonance imaging (MRI) scanners, electrocardiography (ECG)-gated cine images depicting LV function with high contrast and excellent spatial and temporal resolution are readily acquired in breath-holds of 5 to 10 heartbeats. For patients in whom breath-holding and ECG gating are difficult, real-time cine imaging without ECG gating and breath-holding can be performed. LV function can be qualitatively assessed from cine images, or alternatively, parameters such as LV volumes, ejection fraction, and mass may be quantified via computer-based analysis software. In addition, techniques such as myocardial tagging and newer variants can be used to qualitatively or quantitatively assess regional intramyocardial strain, twist, and torsion. Many of the CMR methods have undergone clinical evaluation in the settings of high-dose dobutamine stress testing and determination of myocardial viability. These methods are also very accurate for prognosis in coronary heart disease patients and may be quite useful for the detection of contractile dyssynchrony. When used together with other CMR techniques such as first-pass perfusion imaging or late gadolinium enhancement, CMR of LV function provides a wealth of information in a single imaging study.
Article: Stress Cardiovascular MR Imaging[Show abstract] [Hide abstract]
ABSTRACT: Stress testing in patients with ischaemic heart disease is commonly applied in clinical practice. Cardiovascular MRI has the ability to obtain precise information about left ventricular function, inducible myocardial ischaemia during pharmacological stress and viability in an integrated examination. Adenosine may be used for vasodilatory stress for first-pass perfusion studies and dobutamine stress may be used to monitor wall motion abnormalities. After i.v. application of gadolinium-based contrast agents, areas of fibrosis or chronic infarcts are detected and may be characterized as 'ischaemic' or 'non-ischaemic' scar. The high image quality and the well-tolerated contrast agents may allow cardiovascular MRI to evolve into a routine tool for the serial assessment of patients with known or suspected ischaemic heart disease.
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ABSTRACT: Cardiovascular Magnetic Resonance (CMR) is an accepted gold standard for non-invasive, accurate, and reproducible assessment of cardiac mass and function. The interest in its use for viability, myocardial perfusion and coronary artery imaging is also widespread and growing rapidly as the hardware and expertise becomes available in more centres, and the scans themselves become more cost effective. In patients with heart failure, accurate and reproducible serial assessment of remodelling is of prognostic importance and the lack of exposure to ionizing radiation is helpful. The concept of an integrated approach to heart failure and its complications using CMR is fast becoming a reality, and this will be tested widely in the coming few years, with the new generation of dedicated CMR scanners.European Journal of Heart Failure 10/2000; 2(3):241-52. DOI:10.1016/S1388-9842(00)00096-9 · 6.58 Impact Factor
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ABSTRACT: The development of a number of regenerative strategies in recent years for curing heart disease represents a paradigm shift away from conventional approaches which aim to manage heart disease. Effective administration of pharmaceutical agents targeted directly to the diseased tissue is the key to unlocking the potential of regenerative strategies, which could augment current conventional treatments. The authors review recent advances in targeted drug delivery to diseased cardiac tissue. Various therapeutic methodologies designed to selectively deliver pharmaceutical agents to diseased cardiac tissue are discussed in this review. Targeted delivery of survival and engraftment promoting factors to damaged cardiac tissue can be an important strategy, for example, in creating a suitable microenvironment encouraging the engraftment of stem cells. Further progress in this emerging field is contingent on the discovery of new biomarkers that are upregulated in damaged cardiac tissue and can be targeted for selective drug delivery. Once fully realized, breakthroughs in this field will have direct applications in the diagnosis and treatment of heart disease through more effective tissue-specific drug delivery and improved imaging modalities.Expert Opinion on Drug Delivery 05/2008; 5(4):459-70. DOI:10.1517/17425247.5.4.459 · 4.12 Impact Factor