In 1980, the World Health Organization (WHO) defined cardiomyopathies as “heart muscle diseases of unknown cause” to distinguish cardiomyopathy from cardiac dysfunction due to known cardiovascular causes such as hypertension, ischemic heart disease, or valvular disease. In clinical practice, however, the term “cardiomyopathy” had also been applied to diseases of known cardiovascular cause, including ischemic cardiomyopathy and hypertensive cardiomyopathy. As a result, the 1995 WHO/International Society and Federation of Cardiology (ISFC) Task Force on the Definition and Classification of the Cardiomyopathies expanded the classification to include all diseases affecting heart muscle and to take into consideration etiology as well as the dominant pathophysiology. In the 1995 classification, the cardiomyopathies were defined as “diseases of the myocardium associated with cardiac dysfunction.”

• In 1980, the World Health Organization (WHO) defined cardiomyopathies as “heart muscle diseases of unknown cause” to distinguish cardiomyopathy from cardiac dysfunction due to known cardiovascular causes such as hypertension, ischemic heart disease, or valvular disease.
• In clinical practice, however, the term “cardiomyopathy” had also been applied to diseases of known cardiovascular cause, including ischemic cardiomyopathy and hypertensive cardiomyopathy.
• As a result, the 1995 WHO/International Society and Federation of Cardiology (ISFC) Task Force on the Definition and Classification of the Cardiomyopathies expanded the classification to include all diseases affecting heart muscle and to take into consideration etiology as well as the dominant pathophysiology.
• In the 1995 WHO classification, the cardiomyopathies were defined as “diseases of the myocardium associated with cardiac dysfunction.”

References:

1-Report of the WHO/ISFC task force on the definition and classification of cardiomyopathies. Br Heart J 1980; 44:672.

2- Richardson P, McKenna W, Bristow M, et al. Report of the 1995 World Health Organization/International Society and Federation of Cardiology Task Force on the Definition and Classification of cardiomyopathies. Circulation 1996; 93:841.

3- Maron BJ, Towbin JA, Thiene G, et al. Contemporary definitions and classification of the cardiomyopathies: an American Heart Association Scientific Statement from the Council on Clinical Cardiology, Heart Failure and Transplantation Committee; Quality of Care and Outcomes Research and Functional Genomics and Translational Biology Interdisciplinary Working Groups; and Council on Epidemiology and Prevention. Circulation 2006; 113:1807.

4- Elliott P, Andersson B, Arbustini E, et al. Classification of the cardiomyopathies: a position statement from the European Society Of Cardiology Working Group on Myocardial and Pericardial Diseases. Eur Heart J 2008; 29:270.

5- WRITING COMMITTEE MEMBERS, Yancy CW, Jessup M, et al. 2013 ACCF/AHA guideline for the management of heart failure: a report of the American College of Cardiology Foundation/American Heart Association Task Force on practice guidelines. Circulation 2013; 128:e240.