Pressure-based estimation of right ventricular ejection fraction.

Area of Science:

• Cardiology
• Medical Imaging
• Hemodynamics

Background:

• Cardiac magnetic resonance imaging (MRI) is the standard for measuring right ventricular ejection fraction (RVEF) in pulmonary arterial hypertension (PAH).
• A validated experimental method exists for estimating RVEF from right ventricular (RV) pressure waveforms.

Purpose of the Study:

• To test if a pressure-based method can detect clinically significant RVEF reductions in PAH patients, as determined by cardiac MRI.
• To evaluate the correlation between pressure-derived RVEF and MRI-measured RVEF in PAH patients.

Main Methods:

• Compared RVEF estimates from RV pressure waveforms during right heart catheterization (RHC) with cardiac MRI measurements in 25 PAH patients.
• Used linear regression and ROC curve analysis to assess correlation and diagnostic ability for detecting maladaptive RV response (RVEF <35%).
• Applied an automated, beat-to-beat RVEF estimation method as proof of concept.

Main Results:

• Pressure-based RVEF estimates showed significant correlation with cardiac MRI (r² = 0.78, P < 0.0001).
• The pressure-based method achieved high accuracy in detecting a maladaptive RV response (ROC AUC = 0.94 ± 0.04, sensitivity 81%, specificity 85%).
• Beat-to-beat RVEF estimation also correlated well with MRI (r² = 0.66, P < 0.001) with similar diagnostic accuracy.

Conclusions:

• Pressure-based RVEF estimation is a viable method that correlates with cardiac MRI in PAH patients.
• This method can detect clinically significant reductions in RVEF, supporting its use during RHC.
• Results suggest potential utility for assessing interventions in PAH patients during RHC.