“What causes a heart to have a hole?”

Usually, this is related to a congenital defect. Basically you were born with this. Small defects can be found in the top chambers, the atria, called patent foramen ovales. Sometimes larger defects in the atria are diagnosed called atrial septal defects. The bottom chambers can have defects as well called ventricular septal defects. Sometimes during a heart attack, a defect in the ventricular wall could develop. These defects can be diagnosed on exam leading to an echocardiogram which is a sound wave picture of the heart. If severe, or symptoms are developing, surgery might be needed. Many are without symptoms and are found incidentally.