Construct Validity of a Novel Fiberoptic TAVR Guidewire for Invasive Pressure Measurements
Geert A A Versteeg1, Maarten A B Westerhof1, Niels A Stens2
1Department of Cardiology, Radboud University Medical Center, Nijmegen, the Netherlands.
Background:
A novel fiberoptic transcatheter aortic valve replacement (TAVR) guidewire was developed that enables continuous hemodynamic monitoring, easy pacing over the wire, and guiding of the valve prosthesis.
Objectives:
This study aimed to evaluate construct validity of hemodynamic measurements obtained with the fiberoptic TAVR guidewire compared to conventional fluid-filled pigtail catheters.
Methods:
This prospective registry study included patients undergoing TAVR. Complete hemodynamic assessment was performed in-duplo with the fiberoptic TAVR guidewire and conventional pigtail catheters. Primary endpoint was the agreement between modalities for post-TAVR mean pressure gradient (PG). Secondary endpoints included agreement in assessing paravalvular regurgitation and in-depth signal analysis using a validated automated algorithm.
Results:
This study included 150 patients (mean age 79.7 ± 5.8 years; 46.7% female). Comparison of invasive pressure measurements yielded moderate to excellent agreement (intraclass correlation coefficient [ICC]-range: 0.65 to 0.95). Bias was observed in left ventricular end-diastolic pressure (LVEDP), with the fiberoptic guidewire measuring higher LVEDPs (+3.5 mm Hg). Post-TAVR mean PG showed a mean absolute difference of 2.7 ± 2.1 mm Hg (ICC: 0.67), minimal bias (-0.45 mm Hg), and 87% concordance with a discrete cutoff (10 mm Hg). Good overall agreement was observed for most indices of paravalvular regurgitation (ICC-range: 0.81-0.87). Automated algorithm assessment revealed fewer artefacts and calibration errors for the fiberoptic guidewire (P = 0.048), repeat analysis improved mean PG agreement (ICC-range: 0.80-0.85).
Conclusions:
The fiberoptic guidewire effectively classified clinically relevant transvalvular gradients with limited bias post-TAVR, although it produced higher LVEDPs, possibly reflecting wire-induced leaflet interaction. Algorithm-derived assessment revealed the fiberoptic guidewire producing measurements with fewer artefacts and calibration errors, supporting its proof-of-concept potential to complement current invasive assessment standards.
