The IABP (Intra-Aortic Balloon Pump) is a mechanical device used to support the heart in cases of severe heart failure, cardiogenic shock, or during high-risk heart surgery. The IABP works by inflating and deflating a balloon in the aorta, which increases coronary artery perfusion during diastole and reduces the workload on the heart during systole, improving cardiac output and oxygen delivery.