Cardiomyopathy

Key points

• • Cardiomyopathy is disease of the heart muscle itself, not primarily due to blocked coronary arteries, valve disease or high blood pressure, and it weakens the heart's pumping.
• • There are three classic types (dilated, hypertrophic and restrictive), and modern classifications add others such as arrhythmogenic cardiomyopathy.
• • Dilated cardiomyopathy is the commonest: the heart chambers stretch and thin so the heart pumps weakly, and it can follow alcohol, viral infection or pregnancy.
• • Hypertrophic cardiomyopathy is a thick, stiff heart muscle, often inherited, and it is an important cause of sudden death in young athletes.
• • Restrictive cardiomyopathy is a stiff heart muscle that cannot fill properly, as in infiltration by amyloid.
• • Because the weakened muscle leads to heart failure and dangerous rhythms, cardiomyopathy is an important cause of illness and sudden death.