The AHA Guidelines and Scientific Statements Handbook

Cardiomyopathies

Barry J. Maron

14

Introduction

Defi nitions

Classifi cation

Primary cardiomyopathies

Genetic

Hypertrophic cardiomyopathy (HCM)

Arrhythmogenic right ventricular

cardiomyopathy/dysplasia (ARVC/D)

Left ventricular noncompaction (LVNC)

Ion channelopathies

Mixed genetic and nongenetic

Dilated cardiomyopathy (DCM)

Primary restrictive (nonhypertrophied)

cardiomyopathy

Acquired

Myocarditis (infl ammatory cardiomyopathy)

Stress (“tako-tsubo”) cardiomyopathy

Secondary cardiomyopathies

Recent ESC classifi cation of cardiomyopathies

Introduction

Cardiomyopathies are an important and heteroge-

neous group of diseases for which awareness in both

the public and medical communities has historically

been impaired by persistent confusion surround-

ing defi nitions and nomenclature. Classifi cation

schemes, of which there have been many, are poten-

tially useful in drawing relationships and distinc-

tions between complex disease states for the purpose

of promoting greater understanding, and indeed the

precise language of these diseases is profoundly

important.

Over the past decade with the dramatic advances

in diagnosis, and understanding genetic and other

etiologies, some defi nitions of diseases have become

outdated. Indeed, several new myocardial disease

entities have been identifi ed and associated with

rapid evolution of molecular genetics in cardiology,

including the emergence of ion-channelopathies as

diseases predisposing to primary lethal ventricular

arrhythmias.

This expert consensus document, under the aus-

pices of the American Heart Association (AHA) [1],

constructs a contemporary classifi cation of cardio-

myopathies offering new perspectives to this com-

plex and heterogeneous group of diseases, as well as

clinical applications and implications for cardiac

diagnosis. The classifi cation scheme and disease

defi nitions are designed to facilitate interaction

among clinical and research communities in assess-

ing the diagnosis, prognosis, and management of

these diseases. However, as these new data continue

to emerge, this classifi cation will undoubtedly

require further review and revision.

Defi nitions

The expert AHA consensus panel proposes this defi -

nition: Cardiomyopathies are a heterogeneous group of

diseases of the myocardium associated with mechanical

and/electrical dysfunction, and are due to a variety of

etiologies that frequently are genetic. Cardiomyopathies

are either confi ned to the heart or are part of generalized

systemic disorders, often leading to cardiovascular death

or progressive heart failure-related disability.

Within the broad defi nition, cardiomyopathies

are usually associated with failure of myocardial

The AHA Guidelines and Scientific Statements Handbook
Edited by Valentin Fuster © 2009 American Heart Association
ISBN: 978-1-405-18463-2