Assessment of left ventricular function by 201Tl SPECT using left ventricular cavity-to-myocardium count ratio

Area of Science:

• Nuclear Cardiology
• Cardiovascular Imaging
• Medical Physics

Background:

• Equilibrium radionuclide angiography (ERNA) is the established standard for measuring left ventricular ejection fraction (LVEF).
• Accurate assessment of LVEF is crucial for diagnosing and managing various cardiac conditions.

Purpose of the Study:

• To investigate the correlation between the left ventricular cavity-to-myocardium count ratio (LVCMR) derived from 201Tl myocardial single-photon emission computed tomography (SPECT) and LVEF measured by ERNA.
• To determine if LVCMR can serve as a reliable surrogate for LVEF assessment.

Main Methods:

• 159 patients underwent both 201Tl SPECT and ERNA on the same day.
• LVCMR was calculated from a mid-ventricular short axis slice using regions of interest in the left ventricular cavity (C) and myocardium (Mmax): LVCMR = (C/Mmax) x 100.
• Statistical analysis was performed to assess the correlation between LVCMR and ERNA-derived LVEF.

Main Results:

• A strong positive correlation was observed between LVCMR and LVEF (r = 0.85, P < 0.0001).
• The mean LVCMR was 54±16% and the mean LVEF was 52±15%.
• The regression equation was y = 0.943x + 5.002, indicating a predictable relationship.

Conclusions:

• LVCMR derived from 201Tl SPECT is closely correlated with LVEF determined by ERNA.
• LVCMR provides an easy and rapid method for estimating left ventricular function.
• 201Tl SPECT LVCMR can be a valuable tool in clinical practice for assessing cardiac function.