Interventricular septal shift due to massive pulmonary embolism shown by CT pulmonary angiography: an old sign revisited.

The computed tomographic (CT) pulmonary angiogram appearances of acute right ventricular dysfunction due to massive pulmonary embolus in a patient are described. Abnormal findings comprised right ventricular dilatation, interventricular septal shift, and compression of the left ventricle. These changes resolved following thrombolysis. Use of CT pulmonary angiography to diagnose pulmonary emboli is increasing. Secondary cardiac effects are established diagnostic features shown by echocardiography. These have not been previously described but are important to recognise as they may carry important prognostic and therapeutic implications.