Petechiae Following Angiography: Evidence for Increased Capillary Permeability

Although recent modifications in the chemical structure of radiodiagnostic contrast media have led to a decrease in the incidence of potentially fatal complications such as angioneurotic edema and anaphylactic shock, untoward reactions of varying severity continue to follow angiography (1). These range from serious central nervous system damage to more common minor side-effects including nausea, vomiting, headache, flushing, itching, paresthesias, and urticaria. The development of petechiae as a manifestation of contrast medium toxicity is rarely referred to in the medical literature (2), although the occurrence of hemorrhagic phenomena in patients receiving other iodine-containing compounds is well known (3–10). It is the purpose of the present communication to describe this complication in three patients examined angiographically in our department over a twelve-month period. Clinical and laboratory evidence accumulated from the three cases suggests that the petechiae were not a manifestation of a clotting defect or a hypersensitivity vasculitis, but were the result of increased capillary permeability secondary to endothelial damage produced by the contrast medium. Case Reports Case I: A 54-year-old white woman weighing 65 kg was admitted for evaluation of mitral stenosis, mitral regurgitation, and aortic regurgitation. On one occasion, a skin rash had developed while the patient was taking chlorothiazide, but all other allergies were denied. Forty-five cubic centimeters of Renovist2 was injected into the ascending aorta at 10 kg per square centimeter pressure through a No. 7 French Gensini catheter passed retrograde from the femoral artery where it had been inserted percutaneously. The catheter was then manipulated below the valve, and an additional 40 cc of contrast material was injected into the left ventricle at 7 kg per square centimeter approximately fifteen minutes later. After each injection, the patient experienced a warm flush. During the ventricular injection, a small amount of medium was inadvertently injected into the myocardium despite free flow of blood from the catheter and an undamped pressure tracing. This was followed by nausea, vomiting, and a transient episode of nodal tachycardia which ceased spontaneously. The angiogram showed significant mitral regurgitation and minimal aortic regurgitation. Four hours later, petechiae appeared in both antecubital fossae and then over the trunk, extremities, neck, face, and conjunctivae. There was mild pruritus of the upper extremities, shoulders, and back which lasted fifteen to twenty minutes. No other symptoms were noted, and the findings on physical examination were normal except for the previously observed cardiac findings and the petechiae. Laboratory studies following the angiography (Table I) showed no evidence of a clotting abnormality, autoimmune process, or hemolysis.