“…Fortunately, it is rarely fatal and is only occasionally followed by clinical deterioration requiring surgical intervention or pericardiocentesis. Cardiac tamponade may develop over several hours after the accident due to the osmotic effect of the contrast in the pericardial cavity (Nadimi, Anagnostopoulis and Frank, 1966). Test injection should also eliminate accidental selective injection of an excessive dose of contrast into coronary arteries, other aortic branches, or into the coronary sinus.…”