Related Experiment Video
Updated: Sep 25, 2025

Invasive Hemodynamic Monitoring of Aortic and Pulmonary Artery Hemodynamics in a Large Animal Model of ARDS
Published on: November 26, 2018
Quantitative Blood Volume Analysis and Hemodynamic Measures of Vascular Compliance in Patients With Worsening Heart
Vishal N Rao1, Jennifer Andrews2, Willard N Applefeld3
1Division of Cardiology, Duke University Medical Center, Durham, North Carolina; Duke Clinical Research Institute, Duke University School of Medicine, Durham, North Carolina.
Background:
The role of blood volume (BV) expansion vs a change in vascular compliance in worsening heart failure (HF) remains under debate. We aimed to assess the relationship between BV and resting and stress hemodynamics in worsening HF and to further elucidate the significance of BV in cardiac decompensation.
Methods And Results:
Patients with worsening HF underwent radiolabeled indicator-dilution BV analysis and cardiac catheterization. Intravascular volumes and resting/stress hemodynamics were recorded. Provocative stress maneuvers included change in systolic blood pressure (ΔSBP) from lying to standing and Valsalva and intracardiac pressure changes with leg raise. Correlation between BV and invasive hemodynamics were assessed by linear regression. Of 27 patients with worsening HF, patients' characteristics included mean age 61 ± 12 years, 70% male, 19% Black, and mean ejection fraction 29% ± 15%. Of the patients, 13 (48%) had hypervolemia as measured by total BV, which weakly correlated with ΔSBP by position (R2 = 0.009) and Valsalva (R2 = 0.003) and with right atrial (R2 = 0.049) and pulmonary capillary wedge (R2 = 0.047) pressure changes during leg raise.
Conclusions:
In patients with worsening HF, BV mildly correlated with intracardiac pressures at rest. Provocative maneuvers intended to test vascular compliance did not correlate with BV, indicating that compliance may serve as a stand-alone metric in HF.
Related Concept Videos
Heart Failure II: Pathophysiology
Vascular Resistance
The primary determinants of vascular resistance are vessel diameter, blood viscosity, and vessel length. Among these, vessel diameter plays the most significant role due to the fourth power relationship described by...
Heart Failure V: Medical Management
Cardiac Output and Stroke Volume
In an average resting adult male, the typical cardiac...
Cardiac Output II: Effect of Stroke Volume on Cardiac Output
Preload
Preload refers to the initial elongation of the cardiac myocytes before contraction and is related to the volume of blood filling the heart at the end of diastole, or end-diastolic volume. The...

