Quantification of regional myocardial function by rapid cine MR imaging

Area of Science:

• Cardiovascular Imaging
• Medical Physics
• Diagnostic Radiology

Background:

• Assessing left ventricular function is crucial for diagnosing and managing heart disease.
• Traditional methods for evaluating regional wall motion can be invasive or have limitations in temporal resolution.

Purpose of the Study:

• To evaluate the capability of rapid (cine) magnetic resonance (MR) imaging in quantifying left ventricular function.
• To compare cine MR imaging findings with echocardiography and contrast ventriculography in patients with ischemic heart disease.

Main Methods:

• Acquired 15-20 MR images per cardiac cycle using partial flip angles, short repetition times, and gradient-refocused echoes.
• Qualitatively assessed regional wall motion via cine display and quantitatively measured myocardial thickness in six left ventricular segments.
• Correlated MR findings with echocardiography and contrast ventriculography in 15 patients with ischemic heart disease and 13 normal subjects.

Main Results:

• Cine MR imaging identified abnormal wall motion in 40 of 90 segments in patients with ischemic heart disease, correlating well with other modalities.
• Identified hypokinetic, akinetic, and dyskinetic segments, with reduced systolic wall thickening in abnormal segments (absolute thickening < 2 mm in 31/40).
• Normal subjects showed heterogeneous systolic wall thickening (overall 48% +/- 28%), with variations across segments.

Conclusions:

• Rapid cine MR imaging provides accurate qualitative and quantitative assessment of regional left ventricular function.
• The technique demonstrates potential for improved diagnosis and management of ischemic heart disease due to its speed and display capabilities.
• Cine MR imaging offers a non-invasive method for evaluating myocardial function with high temporal resolution.