In simple words: A hole in the wall of the heart that separates the chambers has developed after birth.

This code represents a defect in the wall separating the heart's chambers (atria or ventricles) that develops after birth.It includes acquired atrial septal defect, acquired ventricular septal defect, and acquired auricular septal defect.

Example 1: A patient presents with new onset shortness of breath and fatigue after a recent severe respiratory infection.Echocardiography reveals a newly formed defect in the atrial septum, consistent with an acquired atrial septal defect., Following a myocardial infarction, a patient develops a ventricular septal defect. This is documented as I23.1 (ST elevation (STEMI) myocardial infarction involving other coronary artery of inferior wall) or I23.2 (ST elevation (STEMI) myocardial infarction involving other coronary artery of other sites) for the initial MI and then I51.0 after the septal defect develops., A patient with a history of endocarditis is found to have an acquired ventricular septal defect. The underlying endocarditis should be coded first followed by I51.0.

Documentation should include evidence from imaging studies such as echocardiography clearly demonstrating the presence and location of the septal defect. Clinical findings such as murmurs, shortness of breath, or heart failure symptoms should also be documented.