Normal range and regional heterogeneity of myocardial perfusion in healthy human myocardium: assessment on dynamic perfusion CT using 128-slice dual-source CT.

Information about myocardial perfusion in healthy hearts is essential for evaluating patients with ischemic heart disease. The purpose of this study was to determine the range and regional variability of myocardial perfusion in normal volunteers on dynamic perfusion computed tomography (CT). Myocardial perfusion was assessed in 19 healthy volunteers (age 33-60 years; 11 men) at rest and during adenosine-induced hyperemia using a 128-slice dual-source CT scanner. Data were quantified as cc/cc/min for the transmural myocardium based on a 17-segment American Heart Association model. Mean myocardial blood flows (MBF) were 1.73 ± 0.33 cc/cc/min during adenosine-induced hyperemia, 0.83 ± 0.21 cc/cc/min at rest, and perfusion reserve was 2.20 ± 0.53. Regional variability was 17 ± 5% for hyperemic perfusion, 18 ± 7% for resting, and 21 ± 6 % for perfusion reserve. Although statistically insignificant, perfusion in the septum was lower at rest and during hyperemia than in other regions. Women tended to have lower perfusion during hyperemia (1.65 ± 0.40 vs. 1.79 ± 0.28 cc/cc/min, P = 0.40), and higher perfusion at rest than men (0.91 ± 0.27 vs. 0.77 ± 0.15 cc/cc/min, P = 0.23), resulting in lower perfusion reserve (1.86 ± 0.31 vs. 2.45 ± 0.53, P = 0.11). This small cohort of healthy volunteers study reveals normal myocardial perfusion parameter on dynamic perfusion CT as follows: mean MBF is 1.73 ± 0.33 cc/cc/min during hyperemia, 0.83 ± 0.21 cc/cc/min at rest, and perfusion reserve is 2.20 ± 0.53. And the study also demonstrates considerable regional heterogeneity of the myocardial perfusion.