Dynamic alteration in myocardium creatine during acute infarction using MR CEST imaging

Area of Science:

• Cardiovascular Imaging
• Biochemistry
• Medical Physics

Background:

• Creatine (Cr) is vital for cardiac function, playing a key role in the creatine kinase reaction.
• Chemical exchange saturation transfer (CEST) MRI is a novel technique for mapping myocardial Cr.
• Understanding dynamic Cr alterations during myocardial infarction is crucial for elucidating cardiac remodeling mechanisms.

Purpose of the Study:

• To investigate the dynamic changes in myocardial creatine levels during acute myocardial infarction using CEST MRI.
• To correlate creatine levels with cardiac structural and functional recovery post-infarction.

Main Methods:

• Seven adult Bama pigs underwent cardiac cine, Cr CEST, and late gadolinium-enhanced (LGE) T1-weighted imaging at 3 and 14 days post-infarction.
• Cardiac function indices (SV, EF) and infarct size were assessed.
• Cr-weighted CEST signals were quantified in infarct, adjacent, and remote myocardial regions.

Main Results:

• Significant increases in stroke volume and ejection fraction were observed from Day 3 to Day 14.
• Myocardial Cr-weighted CEST signal significantly elevated in infarct, adjacent, and remote regions at Day 14 compared to Day 3.
• Moderate negative correlations were found between infarct size and myocardial Cr levels.

Conclusions:

• The dynamic increase in myocardial creatine during acute infarction may be linked to cardiac structural and functional recovery.
• CEST MRI provides valuable metabolic insights into the heart remodeling process following myocardial infarction.
• This study highlights the potential of Cr-CEST MRI in understanding the metabolic underpinnings of cardiac healing.