In this paper, we describe a rare case of a giant aneurysm of the circumflex artery that we managed. A 59‐year‐old female patient presented in cardiogenic shock after partial aneurysm rupture. Giant aneurysms of the circumflex artery are extremely rare entities. The optimal surgical management dictates meticulous preoperative planning and the operation should be carried out on an elective basis. Surgery for giant coronary aneurysms is a challenge. It should be carried out electively to allow detailed imaging and meticulous preoperative planning. Acute cardiac tamponade caused by spontaneous aneurysm rupture carries significant mortality.