A pressure-recording guide wire for measurements of trans-stenotic gradients in arteries. In vitro validation.
OBJECTIVE
A 0.018'' guide wire with a pressure sensor near the tip has been developed for measuring arterial trans-stenotic pressure gradients. The pressure-recording properties of this system in vitro are evaluated.


METHODS
Static and dynamic tests were performed with five guide wires. Dynamic tests (step response and recordings of phase and frequency response) were performed with a pressure generator connected to a recording system and a spectrum analyzer.


RESULTS
Zero drift at 3 hours ranged from -1.9 to 2.2 mmHg/hour. Sensitivity drift ranged from 0.3% to 2.1%/hour. Hysteresis ranged from 0.2% to 4.3% (mean 2.4%). Bending in arcs of 180 degrees with diameters < 4 cm changed sensitivity and zero pressure recordings in all guide wires. Dynamic recordings showed a slight undershoot and no oscillation.


CONCLUSIONS
Static errors exceeded those of external pressure transducers for fluid-filled catheters, indicating suboptimal recordings of absolute pressures. However, the small size, and the good dynamic properties, make this pressure wire a promising device for recording trans-stenotic pressure gradients in arteries.
Abildgaard
A
A
Department of Radiology, National Hospital, Oslo, Norway.
Jensen
O
O
Kløw
N E
NE
D001158:Arteries / Q000473:pathology*; D002404:Catheterization / Q000295:instrumentation*; D003251:Constriction, Pathologic; D066298:In Vitro Techniques; D008961:Models, Structural