Validation of a noninvasive device for measuring filling pressure against invasive pulmonary capillary wedge pressure

Abstract

Background

Intravascular congestion, particularly elevated cardiac filling pressures, is a key component of heart failure and often precedes symptom onset. Early intervention is critical, yet non-invasive tools to detect congestion before symptoms appear are limited.

Objectives

This study evaluates the accuracy of a non-invasive filling pressure (NIFP) device in assessing cardiac filling pressure, compared to pulmonary capillary wedge pressure (PCWP) obtained via Swan-Ganz catheterization.

Methods

Ninety-eight patients undergoing cardiac surgery had NIFP device measurements immediately before PCWP measurements. Elevated filling pressure was defined by PCWP thresholds of >18 mmHg and ≥ 15 mmHg. Receiver Operating Characteristic (ROC) curves and Pearson correlation coefficients were used for analysis.

Results

PCWP measurements were successful in all 98 patients, with 93 (95 %) yielding successful NIFP readings. Using a PCWP >18 mmHg, 14 cases (15 %) were identified with elevated filling pressure. The NIFP device demonstrated an AUROC of 0.84 (p < 0.001), sensitivity of 71.4 %, specificity of 91.1 %, and overall accuracy of 88.2 %. With a PCWP ≥15 mmHg, the AUROC was 0.83, with sensitivity of 66.7 %, specificity of 82.6 %, and overall accuracy of 78.5 %. The Pearson correlation between NIFP and PCWP was 0.55 (p < 0.0001).

Conclusions

The NIFP device shows promise as a non-invasive, accurate tool for detecting elevated filling pressures. Its ease of use and potential as a point-of-care tool could have significant implications for heart failure management and early intervention strategies.