Background: Antiphospholipid syndrome (APS) is a rare autoimmune disease with an increased risk of vascular occlusion and pregnancy complications. As a multisystemic disease, the heart is usually affected by direct (autoimmune action) or indirect (thrombosis) pathological mechanisms. Case Report: A 40-year-old diabetic and hypertensive woman presented with congestive heart failure. The echocardiographic exploration showed reduced left ventricle ejection fraction (20%) and diffuse wall motion abnormalities with multiple large thrombi in the left ventricle. The coronary angiography was normal. The APS was confirmed by positive laboratory tests (La, aCL and aß2GPI). Conclusion: The revelation of APS by cardiac manifestations, mainly cardiac thrombosis, is rarely reported in the literature, and evolution is usually unfavorable.