Iodoalphionic acid

Rapid peripheral intravenous injection of concentrated ionic contrast media produces a brief rise in systemic arterial pressure followed by a prolonged fall the diastolic pressure decreases more than the systolic pressure and the heart slows the pulse contour changes, and the venous pressure rises the arterial hypotension is more marked if injection is rapid. The electrocardiogram can show flattening, splitting, or T-wave inversion tachycardia is probably compensatory, as are the concomitant increases in venous pressure and pulmonary arterial pressure. Hypotension associated with a vasovagal reaction probably explained four deaths from acute coronary insufficiency (two each with iodoalphionic acid and iopa-noic acid) in patients with ischemic heart disease. 

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