Recording of Right Heart Pressures in Man.

Utilizing the right heart catheterization technic of Cournand and Ranges, the cyclic pressure changes in the right auricle and right ventricle have been recorded with the Hamilton manometer in 50 individuals.Catheterization of the right auricle was performed as previously described., The patients experienced little or no discomfort during the procedure. The level of the catheter in the heart by lateral X-ray was taken as zero pressure. Introduction of the catheter with a slightly curved tip into the right ventricle under fluoroscopic control was not difficult as a rule, and was signaled first by a rise above auricular pressure, then by large oscillations at cardiac rate in the saline monometer connected to the catheter.Addition of the long narrow catheter (No. 8 or 9) to the manometer system decreases the natural frequency. Frequencies obtained with this system have varied from about 25 to 50 vibrations per Second. Although not ideal, this range has proved fairly adequate except in the presence of tachycardia or very vigorous cardiac contractions. Oscillatory phenomena were common, especially in low pressure ventricular complexes, but at present it is not certain whether some of these are artifacts dependent upon the presence of the catheter (see Fig. 1A and 2). The general contours of the pulse waves are believed to be reasonably accurate.Results. In 8 normal subjects the right ventricular pressure averaed 22 mm mercury at the height of systole (range 18-28) and about zero during most of diastole. There was a cyclic variation of about one to 3 mm mercury due to quiet respiration (Fig. 1A). The systolic contour was full, resembling curves obtained in dogs by Wiggers. In the few cases of mild and moderate essential hypertension, the pressures were not outside the normal range.