Can right ventricular performance be assessed by equilibrium radionuclide ventriculography?

Area of Science:

• Cardiology
• Nuclear Medicine
• Radiology

Background:

• Assessing right ventricular function is crucial but challenging due to low counts and radiation concerns with conventional methods.
• The first-pass radionuclide method for evaluating right ventricular ejection fraction (RVEF) is limited by low detected counts and patient radiation burden.

Purpose of the Study:

• To modify the gated equilibrium blood pool method for repeated assessment of RVEF.
• To compare the modified gated equilibrium method with the first-pass radionuclide method for RVEF assessment.

Main Methods:

• Modified gated equilibrium blood pool method applied to 43 patients.
• Comparison of RVEF measurements with the first-pass radionuclide method.
• Assessment of RVEF variability and response to pharmacological agents (isoprenaline, prenalterol, nifedipine).

Main Results:

• Excellent agreement between the modified gated equilibrium method and the first-pass method (r = 0.91).
• Low intra-observer (0.03) and inter-observer (0.04) variations for equilibrium studies.
• Significant increases in RVEF observed after isoprenaline and prenalterol administration, and in patients with impaired left ventricular function after prenalterol.

Conclusions:

• Repeated estimation of right ventricular performance is feasible using the modified gated equilibrium radionuclide ventriculography.
• The modified method provides a reliable and reproducible assessment of RVEF, suitable for serial evaluations.
• This technique offers a valuable tool for studying right heart function under various physiological and pharmacological conditions.