Figure 32-29 Characteristic waveforms recorded during passage of a pulmonary artery catheter. Right atrial pressure resembles a central venous pressure waveform and displays a, c, and v waves. Right ventricular pressure shows a higher systolic pressure than seen in the right atrium, although the end-diastolic pressures are equal in these two chambers. Pulmonary artery pressure shows a diastolic step-up when compared with ventricular pressure. Note also that right ventricular pressure increases during diastole whereas pulmonary artery pressure decreases during diastole (shaded boxes). Pulmonary artery wedge pressure has a morphology similar to that of right atrial pressure, although the a-c and v waves appear later in the cardiac cycle relative to the electrocardiogram. (Redrawn from Mark JB: Atlas of Cardiovascular Monitoring. New York, Churchill Livingstone, 1998, Fig. 3-1.)