[Cardiac causes of acute ischemia of lower limbs].

Acute ischemias of the legs of cardiac origin are almost always due to leg embolus caused by fragmentation of an endoauricular or left venticular thrombosis. The two main causes are easily recognized: mitral narrowing and ventricular aneurysm are seldom accompanied by seeding, because a prophylactic treatment with anti-vitamin K is started as soon as the diagnosis is made. Use of prosthetic valves, despite constant improvement in their manufacture and systematic administration of anticoagulant drugs, are always complicated by embolisms (4 to 7% of cases at present). On the other hand, two causes of leg embolisms should be carefully sought since they give rise to revealing seedings. Non-obstructive cardiomyopathy gives a picture of primitive cardiac insufficiency developing progressively. Paroxysmal supraventricular rhythm disorders may be completely overlooked, and only an electrocardiogram continued during 24 hours allows their detection. Embolisms which do not involve the legs, are secondary. Seeding of a chalky fragment from a stenotic aortic valve is very rare. On the other hand, embolisms of anauricular fragment of myxoma and especially membranous embolisms during infectious endocarditis, are not so rare.