To our knowledge, this is the first book dealing exclusively with myocardial contrast two-dimensional echocardiography (MC-2DE), a new and exciting diagnostic methodology for assessment of myocardial perfusion, which has seen rapid development and has now entered the clinical stage. The experi­ mental research and human applications have been described in technical papers published in a variety of journals, but our objective is to provide the reader with a comprehensive and concentrated overview of the field and of the current state of the art. To facilitate appreciation of the significant ad­ vances made and issues yet to be resolved, we are pleased to have several well known specialists contribute their own assessment of specific aspects of MC- 20E and illustrate the method's principles as well as applications. We were faced with inevitable overlaps and some repetitions in the discussion of quan­ titative potentials or limilations of the methodology. Rather than strictly 'streamlining' the text, we decided to accept some redundancy in the interest of presenting a diversity of points of views, reflecting the current evolutionary state of MC-20E. Following a brief reference to the established clinical contrast echocardiog­ raphy, recent developments and validations of the specialized MC-2DE tech­ nique are reviewed, bearing in mind that the field is in a flux and some of the ongoing activities have not as yet been formally reported. Mechanisms of the echo contrast and several new agents are decribed next, and an additional chapter illustrates current thoughts-on optimizing the echo contrast medium.

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1. Introduction and general background.- 1. Evolution of echo contrast concepts.- 2. Assessment of cardiac structures and flow patterns.- 3. Development of echo contrast agents.- 4. Consideration of echo contrast mechanism and safety.- References.- 2. Development and validation of MC-2DE methodology.- 1. Initial exploration of MC-2DE and its validity.- 2. Characteristics and studies of myocardial echo contrasts.- 3. Echo contrast safety and toxicity.- 4. Transpulmonary echo contrast investigations.- 5. Quantitative MC-2DE methods and their limitations.- 6. MC-2DE measurement of ischemic risk area and infarcts.- 7. Assessment of coronary stenosis and myocardial blood flow.- 8. Physiological studies and miscellaneous MC-2DE applications.- 9. Initial clinical MC-2DE reports.- 10. Potential surgical application of MC-2DE.- References.- 3. Contrast agents for myocardial perfusion studies: Mechanisms, state of the art, and future prospects.- 1. Introduction.- 2. The source of ultrasonic contrast effect.- 3. Physical influences on ultrasonic contrast effect.- 3.1 Viscosity.- 3.2 Surfactant properties.- 3.3 Influence of pH.- 4. Specific agents reported as echocardiographic contrast agents.- 4.1 Carbon dioxide.- 4.2 Hydrogen peroxide.- 4.3 In vivo generation of contrast.- 4.4 Contrast formed by bubbles in gelatin or Haemaccel®.- 4.5 Saccharide particles as ultrasound contrast agents.- 4.6 Heavy liquids: Fluorochemicals and fat emulsions.- 4.7 Highly viscous solutions.- 4.8 Sonicated albumin microbubble suspensions.- 5. The use of high intensity sonication for microbubble creation.- 5.1 Background.- 5.2 Animal studies using sonicated albumin.- 5.3 Human studies using sonicated albumin.- 6. Conclusion.- Acknowledgements.- References.- 4. Significance and selection of contrast solution for myocardial contrast echocardiography.- 1. Introduction.- 2. Current echo contrast media.- 3. Properties of the ECM: Microbubble size, osmolality, viscosity, and stability.- 3.1 Microbubble size.- 3.1.1 Preparation of the microbubbles.- 3.1.2 Physicochemical properties and effects on bubble size.- 3.1.3 Effects of microbubble size on myocardial perfusion.- 3.2 Osmolality, viscosity, and stability of the mixture of carrier solution and microbubbles.- 4. Evaluation of the echo contrast media used so far.- 5. Echo contrast safety and effectiveness.- 6. Some conclusions.- Acknowledgements.- References.- 5. Side effects and potential toxicity of myocardial contrast echo Cardiography.- 1. Introduction.- 2. Possible mechanisms of toxicity.- 2.1 Adverse effects related to contrast media.- 2.2 Adverse effects related to microbubbles: Capillary plugging.- 2.3 Cavitation/resonance and ultrasonic effects.- 2.4 Side effects related to injection technique.- 2.5 Patient related adverse effects.- 3. Animal studies.- 4. Human experience.- 5. Conclusions.- References.- 6. Ischemic 'risk area' determination using myocardial contrast two-dimensional echocardiography.- 1. What is the 'risk area'?.- 2. What is the significance of the 'risk area' ?.- 2.1 Duration of coronary occlusion.- 2.2 Status of collateral circulation.- 2.3 Infarct size/'risk area' ration.- 3. A historical perspective to the measurement of 'risk area'.- 4. Role of MCE is the assessment of 'risk area'.- 4.1 Validation of the technique.- 4.2 'positive' versus 'negative' RA.- 4.3 Relationship of RA to extent of abnormal wall motion.- 4.4 Time-dependent changes in RA.- 4.5 Relationship of RA to infarct size.- 4.6 Relationship between RA and hemodynamic parameters.- 4.7 Relationship of RA and LV systolic function.- 5. The lateral borders of the 'risk area'.- 6. Summary.- Acknowledgements.- References.- 7. Quantitation of regional myocardial perfusion using myocardial contrast two-dimensional echocardiography.- 1. Coronary blood flow versus nutrient (myocardial) blood flow.- 2. Large microbubbles and blood flow.- 3. Small microbubbles and blood flow.- 3.1 Method of analysis.- 3.2 Subselective injection into a coronary artery.- 3.3 Selective injection into the left main coronary artery.- 3.4 Assessment of coronary blood flow reserve.- 3.5 Intraoperative assessment of blood flow.- 3.6 What is the best parameter to measure?.- 3.7 Epicardial versus endocardial flow.- 3.8 Assessment of myocardial flow following a venous injection of contrast.- 4. Summary.- Acknowledgements.- References.- 8. Coronary venous myocardial contrast echocardiography.- 1. The rational of retrograde infusions.- 2. Experimental retrograde MC-2DE models.- 3. Experimental observations.- 4. Suitability and limitations of the retrograde MC-2DE method.- 5. Future retrograde MC-2DE potentials and prospects 148 References.- 9. Assessment of contrast decay half life by MC-2DE: Preliminary clinical experience.- 1. Introduction.- 2. Echocontrast agents.- 3. Registration of myocardial contrast echocardiograms.- 4. Analysis of MC-2DE images.- 5. T50 values derived from MC-2DE.- 6. Safety of MC-2DE.- 7. Reproducibility of T50 measurements.- 8. Clinical applications of T50.- 9. Limitations and future prospects.- References.- 10. Clinical trials with a new myocardial contrast agents.- 1. Introduction.- 2. Qualitative contrast echocardiography in humans.- 3. Quantitative contrast echocardiography in humans.- 4. Future directions.- Acknowledgements.- References.- 11. Clinical evaluation of severity of coronary arterial stenosis by contrast echomyocardiography.- 1. Introduction.- 2. Method.- 3. Results.- 4. Discussion.- 4.1 Myocardial echo enhancement.- 4.2 Contrast agents.- 4.3 Quantitative analysis.- 4.4 Problems in clinical applications.- 5. Summary.- References.- 12. Clinical applications of myocardial contrast echocardiography.- 1. Introduction.- 2. Myocardial contrast echocardiography in relation to regional myocardial perfusion.- 3. Contrast echocardiography during coronary angioplasty.- 4. Assessment of coronary vascular reserve by myocardial contrast echocardiography.- 5. Safety of myocardial contrast echocardiography in humans.- 6. Limitations.- 7. Perspectives and future directions.- Acknowledgement.- References.- 13. The issue of an intravenous MC-2DE methodology. A typical early study.- Section One: Recapitulation of problems and potentials by the volume-editor Samuel Meerbaum.- Section Two: Evaluation of myocardial echo enhancement by intra venous con…