Arterial excess‑reservoir pressure integral as a predictor of cardiovascular complications in patients with acute coronary syndrome

Reservoir-excess pressure parameters are independently associated with NT-proBNP in older adults

AIMS

Parameters derived from reservoir-excess pressure analysis have been demonstrated to predict cardiovascular events. Thus, altered reservoir-excess pressure parameters could have a detrimental effect on highly-perfused organs like the heart. We aimed to cross-sectionally determine whether reservoir-excess pressure parameters were associated with N-terminal pro-brain-type natriuretic peptide (NT-proBNP) in older adults.

METHODS

We studied 868 older adults with diverse cardiovascular risk. Reservoir-excess pressure parameters were obtained through radial artery tonometry including reservoir pressure integral, peak reservoir pressure, excess pressure integral (INTXSP), systolic rate constant (SRC) and diastolic rate constant (DRC). Plasma levels of NT-proBNP, as a biomarker of cardiac overload, were analysed by the Proximity Extension Assay technology.

RESULTS

Multivariable linear regression analyses revealed that all reservoir-excess pressure parameters studied were associated with NT-proBNP after adjusting for age and sex. After further adjustments for conventional cardiovascular risk factors, INTXSP [β = 0.191 (95% confidence interval, CI: 0.099, 0.283), P < 0.001], SRC [β = -0.080 (95% CI: -0.141, -0.019), P = 0.010] and DRC [β = 0.138 (95% CI: 0.073, 0.202), P < 0.001] remained associated with NT-proBNP. Sensitivity analysis found that there were occasions where the association between SRC and NT-proBNP was attenuated, but both INTXSP and DRC remained consistently associated with NT-proBNP.

CONCLUSIONS

The observed associations between reservoir-excess pressure parameters and NT-proBNP suggest that altered reservoir-excess pressure parameters may reflect an increased load inflicted on the left ventricular cardiomyocytes and could have a potential to be utilized in the clinical setting for cardiovascular risk stratification.

The modified arterial reservoir: An update with consideration of asymptotic pressure (P∞) and zero-flow pressure (Pzf)

This article describes the modified arterial reservoir in detail. The modified arterial reservoir makes explicit the wave nature of both reservoir (P_res) and excess pressure (P_xs). The mathematical derivation and methods for estimating P_res in the absence of flow velocity data are described. There is also discussion of zero-flow pressure (P_zf), the pressure at which flow through the circulation ceases; its relationship to asymptotic pressure (P_∞) estimated by the reservoir model; and the physiological interpretation of P_zf . A systematic review and meta-analysis provides evidence that P_zf differs from mean circulatory filling pressure.