Heart failure is a major, cause of death worldwide, most frequently secondary toacardiomyopathicdisorder. The rolesofviruses, immunity, cytokines and genetics as sources of heart failure have been relatively understated in the rapidly developing world of clinical cardiology. Yet, great progress in molecular biology and the recent application of new techniquesto studiesoftheetiologyandpathogenesisofcardiomyopathies and heart failure has shed new light in an area ready to undergo major developmentsandadvances. This book is an effort to present an up-to-date account of eXIstmg knowledge,includingrecentdevelopmentsinthisfield. Chapterscovering severaldisciplinesincludingbiochemistry,immunology,molecularbiology, virology,epidemiologyandclinicalmedicinehavebeenincluded,offeringa "bench-to-bedside"and"bedside-to-bench"criticalreviewofeveryaspects of heart failure and cardiomyopathies, by world renowned, expert researchers and clinicians. These opinion leaders review all significant advances in our understandingofheart failure and cardiomyopathies, and describe theimprovements indiagnosis and treatment that areexpectedto optimize the overall management of patients. The identification of establishedornewlyrecognizedmolecules,cytokines,viruses,andgenes,as well as an understandingofthe mechanisms by which these factors may cause cardiomyopathic disorders and induce heart failure depends on a multidisciplinaryapproachwhichthisbookattemptstouniquelyencompass. Therefore,wehopethatitwillbeanimportantresource,notonlyforclinical cardiologists,butalso forgeneralpractitioners,pediatriciansandspecialists in infectious diseases, as well as trainees and graduates in biochemistry, immunology, genetics, molecular biology, virology, pharmacology, and epidemiology. AkiraMatsumori,MD,PhD Ie INTRODUCTORYCHAPTER CARDIOMYOPATHIESANDHEARTFAILURE Biomolecular,InfectiousandImmuneMechanisms AkiraMatsumori,MD,PhD DepartmentofCardiovascularMedicine KyotoUniversityGraduateSchoolofMedicine Kyoto,Japan 1 SUMMARY Theclinicalpresentationofviralmyocarditisisvariable. Whenmyocardial necrosis is diffuse, congestive heart failure develops, and later, dilated cardiomyopathy. If the myocardial lesions are localized, a ventricular aneurysmforms. Whencomplicatedbyarrhythmias,myocarditispresentsas arrhythmogenic right ventricular cardiomyopathy. When myocardial necrosisislocalizedtothesubendocardialregion,restrictivecardiomyopathy may develop. While it has not been established that hypertrophic cardiomyopathy maybeacomplicationofviral myocarditis, asymmetrical septal hypertrophy has, in fact, sometimesbeen observed in patients with myocarditis. TheimportanceofhepatitisCvirusinfectionhasrecentlybeen notedinpatientswithmyocarditis,dilatedandhypertrophiccardiomyopathy.