No abstract

The iodinated contrast agents used in oral cholecystography impair peripheral iodothyronine-5'-deiodinase activity, resulting in a transient decrease in serum 3,5,3'-triiodothyronine (triiodothyronine, T3) and in increases in serum 3,3',5'-triiodothyronine (reverse T3, rT3) and thyroxine (T4) concentrations. A related iodinated contrast agent, diatrizoate, is employed in coronary angiography. The effect of diatrizoate (Renografin-76) on serum T4, T3, rT3, and thyroid stimulating hormone (thyrotropin, TSH) concentrations and the TSH and T3 responses to thyrotropin releasing hormone (TRH) were evaluated in seven euthyroid patients before and on the fifth day following coronary angiography. No significant changes were observed. Thus, diatrizoate, in contrast to the oral cholecystographic agents, appears to have little or no clinically important effect on thyroid hormone metabolism in man.

transbronchial catheterization of the left heart are presently commonplace maneuvers in the study of heart disease.1 They are not without risk, however, and are accompanied by an impressive morbidity and a small inortality.6 For this reason and because of other inherent difficulties, it has been our practice to Introduction of the catheter into the left ventricle was routinely performed in subsequent conventional catheterizations, and transthoracic puncture was done only when the left ventricle could not be attained in retrograde fashion. Materials and MethodsRetrograde left ventricular catheterization was attempted in 65 patients. Two were women and the remainder were men between the ages of 33 and 68. The diagnoses included arteriosclerotic and rheumatic heart disease and a few instances of congenital cardiac deformity. A number of patients had multiple valvular lesions, and studies were performed in several in an effort to assess the relative importance of aortic stenosis and incompetence, mitral stenosis and regurgitation, and the like. Four subjects had no cardiac disorders.In patients with coronary artery disease, left heart studies were carried out in addition to coronary angiography.All patients were premedicated with meperidine, secobarbital, and penicillin, and all were studied in the basal state, generally in the morning. Electrodes were attached and the electrocardiogram was