Heart failure

Cardiomyopathy, which literally means "heart muscle disease," is the deterioration of the function of the myocardium (i.e., the actual heart muscle) for any reason. http://en.wikipedia.org/wiki/Cardiomyopathy

This is usually referred to as اعتلال عضلة القلب - hence my confidence level of 3, as I can't be 100% sure that قصور and اعتلال mean the same thing in the medical profession. See e.g.

أصبح مرض اعتلال وضعف عضلة القلب (CARDIOMYOPATHY) من المشكلات الصحية الرئيسة في العالم ففي أوروبا يوجد حوالي خمسون مليون مريض (من أصل ألف ...
www.alalamonline.net/صحة-عامة/أعتلال-عضلة-القلب.html

اعتلال عضلة القلب (بالإنكليزية: Cardiomyopathy) يحدث عندما يكون هناك خلل في وظائف الخلايا العضلية القلبية. و مرضى اعتلال عضلة القلب معرضيب إلى الموت المفاجئ ...
ar.wikipedia.org/wiki/اعتلال_عضلة_القلب

Myocardial infarction (MI) or acute myocardial infarction (AMI), commonly known as a heart attack, is the interruption of blood supply to part of the heart, causing heart cells to die. This is most commonly due to occlusion (blockage) of a coronary artery following the rupture of a vulnerable atherosclerotic plaque, which is an unstable collection of lipids (fatty acids) and white blood cells (especially macrophages) in the wall of an artery. The resulting ischemia (restriction in blood supply) and oxygen shortage, if left untreated for a sufficient period of time, can cause damage or death (infarction) of heart muscle tissue (myocardium). It was translated in Arbic as احتشاء عضل القلب.

Myocardial infarction is the death of heart muscle from the sudden blockage of a coronary artery by a blood clot. Coronary arteries are blood vessels that supply the heart muscle with blood and oxygen.

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