Boot-shaped heart means that the waist changes from an obtuse angle to a right angle, and the heart looks like a boot. This is because the left ventricle expands and protrudes (the toe of the boot), and the right ventricle also expands (the left heart and waist are pulled to the right, resulting in the depression of the heart and waist), and the combination of the two appears. It is more common in aortic insufficiency. Occasionally, aortic stenosis can also be seen.