Prosthetic heart valve malfunction: plain film findings.

Clinical signs of heart valve malfunction are often not specific so that recognition frequently depends on nonclinical methods. The chest radiographs of 34 patients with 41 prosthetic valve malfunctions (PVM) were compared before and after valve failure. The most frequent sign of PVM is postcapillary hypertension (90%). A marked increase in heart size occurs with regurgitation but not with obstruction. A change in attitude of a valve of more than 6 degrees. in the aortic and 12 degrees in the mitral position is virtually diagnostic of dehiscence. This was seen in 52% of patients with paravalvular regurgitation and in 29% of all patients with PVM. When dehiscence is suspected on clinical or radiologic grounds the valve should be examined fluoroscopically. Changes in the azygos vein and the vascular pedicle of the heart and the development of pleural effusions are less useful signs of PVM. Although the chest radiograph is often not diagnostic of PVM, it may point to the need for definitive investigation.