Cardiovascular Magnetic Resonance (CMR) has undergone substantial development and offers important advantages compared with other well-established imaging modalities. In the November/December issue of Progress in Cardiovascular Diseases, published by Elsevier, a series of articles on key topics in CMR will foster greater understanding of the rapidly expanding role of CMR in clinical cardiology.
"Until a decade ago, CMR was considered mostly a research tool, and scans for clinical purpose were rare," stated guest editors Theodoros D. Karamitsos, MD, PhD, and Stefan Neubauer, MD, of the University of Oxford Centre for Clinical Magnetic Resonance Research and the Department of Cardiovascular Medicine, John Radcliffe Hospital, Oxford, UK. "With technical advances in hardware and software, CMR is now considered a powerful tool to assess ventricular function, cardiac morphology, perfusion, viability and metabolism, as well as the vasculature. All of this imaging is possible without the need for ionizing radiation, and with high resolution in three dimensions. CMR is now a highly attractive first-line test for routine clinical indications such as the evaluation of ischemic heart disease and nonischemic cardiomyopathies."
"It is anticipated that CMR may still have its best years to come. In the near future, the technique will become even more patient and user friendly, with simplified acquisition approaches, faster real-time scanning protocols, novel contrast agents that target specific molecules for diagnosis and treatment, and advanced tissue characterization that will further improve in vivo assessment of myocardial pathology," commented Dr. Karamitsos and Prof. Neubauer.
Key Points:
Cardiovascular Magnetic Resonance: A Powerful Diagnostic and Prognostic Tool in Modern Cardiology
Theodoros D. Karamitsos, Stefan Neubauer
CMR is a relatively new imaging technique that has developed progressively over the last three to four decades. CMR's acceptance has been facilitated by its ability to acquire images faster, the introduction of steady-state free-precision sequences for cine imaging, the development of the late gadolinium enhancement technique to assess myocardial scarring and fibrosis, and the improvement of stress perfusion.
Cardiovascular Magnetic Resonance: Physics and Terminology
Christopher T. Rodgers, Matthew D. Robson
The widespread availability of magnetic resonance imaging (MRI) equipment in hospitals demonstrates that magnetic resonance (MR) has extraordinary value in medicine. This primer provides an introduction to MRI and its application in cardiology. The authors summarize the essential physics underlying CMR, present a compact glossary of important terminology, and provide references as starting points for further study.
Assessment of Myocardial Ischemia with Cardiovascular Magnetic Resonance
Bobak Heydari, Michael Jerosch-Herold, Raymond Y. Kwong
The assessment of patients presenting with symptoms suspicious for myocardial ischemia remains one of the most common and challenging clinical scenarios faced by physicians. CMR can provide comprehensive diagnostic and prognostic assessment of myocardial ischemia for patients presenting with chest pain, stable angina, or for myocardial viability. Stress CMR is a highly accurate and safe diagnostic modality that has widespread patient applicability and has proven advantageous for certain patient subgroups, including those with poor echocardiographic windows, baseline left ventricular dysfunction, and resting wall motion abnormalities. This review covers techniques of ischemia assessment with CMR and compares CMR with other commonly used noninvasive modalities.
Evaluation of Myocardial Viability With Cardiac Magnetic Resonance Imaging
Suchi Grovera, Govindarajan Srinivasana, Joseph B. Selvanayagam
The management of patients with ischemic cardiomyopathy and history of myocardial infarction critically depends on the assessment of left ventricular (LV) function and viability. All of the currently used imaging modalities for viability assessment have substantial limitations related to image quality, poor spatial resolution, and attenuation artifact. The authors discuss how CMR overcomes these limitations and established itself as a reliable alternative to echocardiography and nuclear techniques.
Late Gadolinium Enhancement CMR Predicts Adverse Cardiovascular Outcomes and Mortality in Patients With Coronary Artery Disease: Systematic Review and Meta-Analysis
Filip Zemrak, Steffen E. Petersen
CMR has a recognized role in diagnosing and monitoring coronary artery disease (CAD). Multiple studies have shown that CMR can predict adverse outcomes. The authors review contemporary available literature to establish the role of CMR with late gadolinium enhancement (LGE) in predicting mortality and major adverse cardiac events (MACEs) in patients with CAD. They found that the presence of LGE increases the hazards of death by more than 4 times and of MACE by almost four times. The size of LGE (per gram or percent) increases the hazards of death and MACE by 4% and 5%, respectively. The presence and size of LGE predict mortality and MACE in CAD.
The Role of Cardiovascular Magnetic Resonance in Patients With Acute Coronary Syndromes
Erica Dall′Armellina, Robin P. Choudhury
CMR imaging is a recognized technique for characterization of myocardial tissue in stable ischemic heart disease. In addition, CMR's ability to provide a more complete characterization of myocardial tissue and to distinguish scarred from viable myocardium suggest a further role for CMR in diagnosing and stratifying patients with chest pain/acute coronary syndromes (ACSs) at admission or in the early hours post revascularization. The authors evaluate the potential clinical role of CMR in the acute setting, highlighting its advantages and limitations.
Coronary Imaging With Cardiovascular Magnetic Resonance: Current State of the Art
Amedeo Chiribiri, Masaki Ishida, Eike Nagel, Rene M. Botnar
CMR allows noninvasive and radiation-free visualization of both the coronary arteries and veins, with the advantage of an integrated assessment of cardiac function, viability, perfusion, and anatomy. Moreover, magnetic resonance offers the possibility of coronary vessel wall imaging, therefore assessing the anatomy and pathology of the normal and diseased coronary vessels noninvasively. Coronary magnetic resonance angiography is challenging because of cardiac and respiratory motion and the small size and tortuous path of the coronary vessels. The authors provide an update on current technical improvements in coronary magnetic resonance angiography, including how to optimize the acquisition protocols, and give an overview of its current clinical applications.
The Current and Emerging Role of Cardiovascular Magnetic Resonance in the Diagnosis of Nonischemic Cardiomyopathies
Theodoros D. Karamitsos, Jane M. Francis, Stefan Neubauer
CMR allows an accurate and reproducible assessment of cardiovascular anatomy and ventricular function, and it also provides detailed myocardial tissue characterization. These unique capabilities make it particularly attractive for the initial assessment and longitudinal follow-up of patients with cardiomyopathies. This review presents the main CMR features of common nonischemic cardiomyopathies, with particular focus on the specific advantages of this imaging modality.
Cardiovascular Magnetic Resonance Imaging in Myocarditis
Helene Childs, Matthias G. Friedrich
Only 10% of patients with myocarditis have clinical symptoms. Most are often left without a conclusive diagnosis, potentially subject to further myocardial injury. This paper reviews how CMR is being used for noninvasive assessment of patients with suspected myocarditis, facilitating assessment of all forms of myocarditis and differentiation from other cardiomyopathies. A recent international consensus on three diagnostic criteria for CMR in the clinical setting is discussed. Although definite diagnosis of myocarditis remains challenging, the outcome of this disease necessitates further investigation with the objective of providing robust noninvasive tests.
The Role of Cardiovascular Magnetic Resonance in the Evaluation of Valve Disease
Theodoros D. Karamitsos, Saul G. Myerson