Catheter-Induced Errors in Pressure Measurements in Vessels: An In-Vitro and Numerical Study

Abstract

Accurate measurement of blood pressure is important because it is a biomarker for cardiovascular disease. Diagnostic catheterization is routinely used for pressure acquisition in vessels despite being subject to significant measurement errors. To investigate these errors, this study compares pressure measurement using two different techniques in vitro and numerical simulations. Pressure was acquired in a pulsatile flow phantom using a 6F fluid-filled catheter and a 0.014” pressure wire, which is considered the current gold standard. Numerical simulations of the experimental set-up with and without a catheter were also performed. Despite the low catheter-to-vessel radius ratio, the catheter traces showed a 24% peak systolic pressure overestimation compared to the wire. The numerical models replicated this difference and indicated the cause for overestimation was the increased flow resistance due to the presence of the catheter. Further, the higher frequency pressure oscillations observed in the wire and numerical data were absent in the catheter, resulting in an overestimation of the pulse wave velocity with the latter modality. These results show that catheter geometry produces significant measurement bias in both the peak pressure and the waveform shape even with radius ratios considered acceptable in clinical practice. The wire allows for more accurate pressure quantification, in agreement with the numerical model without a catheter.

Pressure Difference Estimation in Carotid Bulbs using Vector Flow Imaging - A Phantom Study

“…A discrepancy of ± 5-10 mmHg between catheter and noninvasive methods has previously been considered as clinically acceptable [21], [22]. However, the invasive practice of the fluid-filled catheter, the inaccuracy [20], and the high imprecision observed in our study challenges the catheter as an ideal reference method. Precise evaluation of vortices and pressure differences in the carotid bulb may be important for understanding hypertension [5], [6], and correct diagnosis can ultimately result in alleviation of symptoms or even treatment of the disease.…”

“…Another factor was three outliers among the catheter measurements that we were unable to explain. Furthermore, catheterization requires introduction of a foreign object into the bloodstream, thus altering the blood flow and pressures from the initial conditions [20].…”

Noninvasive Estimation of Pressure Changes Using 2-D Vector Velocity Ultrasound: An Experimental Study With <italic>In Vivo</italic> Examples

“…Despite the advantage offered by a pressure catheter in terms of low inter-operator dependency, the procedure suffers some severe limitations as it is highly invasive and requires the use of ionizing radiation for guidance in an angio suite. Furthermore, a recent report from De Vecchi et al [2] demonstrated that the accuracy of catheters depends on the size and shape of the catheter. A 24 % overestimation of the peak systolic pressure was found, when using a routinely employed catheter compared to a pressure sensing wire, which is considered the gold standard [2], [3].…”

“…Furthermore, a recent report from De Vecchi et al [2] demonstrated that the accuracy of catheters depends on the size and shape of the catheter. A 24 % overestimation of the peak systolic pressure was found, when using a routinely employed catheter compared to a pressure sensing wire, which is considered the gold standard [2], [3].…”

Device closure of atrial septal defect with severe pulmonary hypertension in adults: Patient selection with early and intermediate term results

“…Although the basal PVRI was significantly elevated, it showed a significant reduction following breathing 100% O 2 (9.6 ± 1.6 to 5.4 ± 1.1 Wu m 2 ). Although, cardiac catheterization has been considered as a gold standard to determine the operability in this subset of patients, catheterization data are significantly limited by a number of assumptions and inaccuracies in estimates and calculations . Hence, the need to take into consideration other clinical, radiological, and echocardiographic parameters as was done in this study.…”