New method for calculating right ventricular ejection fraction using gated myocardial perfusion studies.

Area of Science:

• Nuclear Cardiology
• Cardiovascular Imaging
• Ventricular Function Assessment

Background:

• Accurate quantification of right ventricular ejection fraction (RVEF) is vital for managing right heart failure and cor pulmonale.
• Traditional methods using Thallium-201 (Tl-201) had limitations in visualizing the right ventricle.
• Technological advancements with Technetium-99m (Tc-99m) labeled agents have improved right ventricular visualization.

Purpose of the Study:

• To introduce and validate a novel method for quantifying RVEF using gated myocardial perfusion (GMP) imaging.
• To compare the accuracy and reliability of this new GMP-based RVEF quantification against first-pass radionuclide ventriculography (FPRNA).

Main Methods:

• Fifty-two patients undergoing routine GMP imaging were included in the study.
• Tc-99m tetrofosmin was administered, followed by both FPRNA and GMP studies.
• Regions of interest were manually drawn on GMP slices to delineate the right ventricle at end-diastole and end-systole for RVEF calculation.

Main Results:

• The mean RVEF values obtained by GMP imaging (51.9 +/- 12.3%) closely matched those from FPRNA (51.8 +/- 10.8%).
• A strong correlation (r = 0.81) was observed between the RVEF measurements from both methods, with no statistically significant difference (P = 0.85).
• Excellent intraobserver (r = 0.87) and interobserver (r = 0.82) agreement further supports the method's reliability.

Conclusions:

• This novel method provides a convenient and accurate approach for RVEF quantification within routine tomographic gated myocardial perfusion studies.
• The findings suggest GMP imaging can be effectively utilized for assessing right ventricular function, complementing existing diagnostic tools.
• This technique offers a valuable alternative for evaluating patients with suspected or known right heart conditions.