Nucl Med Mol Imaging.  2013 Sep;47(3):158-165.

Myocardial Blood Flow and Flow Reserve in Proximal and Mid-to-Distal Lesions of Left Anterior Descending Artery Measured By N-13 Ammonia PET/CT

• Cho SG
• Kim JH
• Cho JY
• Kim HS
• Bom HS

Abstract

PURPOSE
The purpose of this study is to compare the myocardial blood flow (MBF) and flow reserve (MFR) between proximal and mid-to-distal lesions of the left anterior descending artery (pLAD and mdLAD, respectively) using N-13 ammonia positron emission tomography/computed tomography (PET/CT).
METHODS
Subjects were 11 patients (six men and five women, mean age 64.5 years) with known coronary artery disease (CAD) involving LAD studied by N-13 ammonia PET/CT. They were divided into two groups by the location of stenotic lesions, i.e. pLAD versus mdLAD. Global and regional MBF and MFR were measured and compared. Characteristics of perfusion defects including the number of involved segments, basal area involvement, location, size, and shape were also compared between the two groups.
RESULTS
The regional MFR in mid-anterior segment was significantly lower in pLAD group (1.80+/-0.35 vs 2.76+/-1.13 for pLAD and mdLAD groups, respectively, p=0.034), while global MFR was not different (2.10+/-1.10 vs 2.34+/-0.84). Both stress and rest MBF in LAD territories were not different in both groups. The size of the perfusion defects were significantly larger in pLAD group (44.0+/-11.5 % vs 21.1+/-15.8 %, p=0.041). Other characteristics such as location, basal area involvement, and shape were not significantly different between two groups.
CONCLUSIONS
The proximal lesion makes lower MFR in the mid-anterior segment and larger perfusion defect in the LAD territory but comparable MBF compared with mdLAD lesion.

Keyword

N-13 ammonia positron emission tomography; Myocardial blood flow; Myocardial flow reserve; Perfusion defect; Left anterior descending artery

MeSH Terms

Ammonia*
Arteries*
Blood*
Coronary Artery Disease
Electrons
Female
Humans
Male
Perfusion
Ammonia