Cardiac gating in intravenous DSA

ECG-gating of a pulsed radiation exposure during end-diastole using digital subtraction angiography shows significantly better results in the examination of the aortic arch vessels and pulmonary arteries and may be expected to decrease the rate of false positive diagnosis of stenosis when examining renal arteries. Different types of misregistration artifacts due to a smear effect by integrating several television frames using non-gated DSA are described and schematically explained. Furthermore, a short description of the difficulties which may be encountered with ecg-gated DSA--mainly rapid changes of heart frequency--is given.