Reliability of pressure recordings via catheters used for transluminal coronary angioplasty.

Because of common difficulties in obtaining adequate pressure tracing during transluminal coronary angioplasty, the pressure transmission characteristics of catheter systems used for angioplasty were determined. Transmission of cine wave pressures (0.2 to 14 Hz) and of arterial pressure pulses reproduced in vitro was evaluated. Following adequate elimination of air bubbles from the system, the Grüntzig dilatation catheters yielded satisfactory frequency response curves and thus good reproduction of arterial pressure waveforms. The Simpson-Robert catheter showed clearly inferior frequency response characteristics, explaining the more significant damping of the pressure tracings. However, mean pressures were reliably recorded with each type.