[Evaluation of the association between left coronary artery stenosis degree and myocardial perfusion by 64 multi-slice].

OBJECTIVE

To evaluate the association between left coronary artery stenosis degree and myocardial perfusion by 64 multi-slice CT.

METHODS

A total of 223 patients underwent 64 multi-slice CT coronary artery images (CTA) were included and divided into normal group (91 cases), mild stenosis group (72 cases), moderate stenosis group (36 cases) and severe stenosis group (24 cases). Myocardial density was measured at apical, septal and lateral segments. Myocardial density in infarcted segments was compared to non-infarct segments in 11 patients with old myocardial infarction (all from severe stenosis group).

RESULTS

Myocardial density was significantly lower at apical segments [(55.8 ± 21.4) HU vs. (75.3 ± 7.5) HU], at septal segment [(87.8 ± 3.3) HU vs. (98.2 ± 5.2) HU] and at lateral segment [(86.8 ± 7.9) HU vs. (95.6 ± 11.6) HU] in severe stenosis group than in normal group (all P < 0.05). Myocardial density of patients with old myocardial infarction was significantly reduced in non-infarct segment [(70.9 ± 8.3) HU vs.(98.7 ± 7.3) HU, P < 0.01] and increased in infarct segment [(42.5 ± 15.7) HU vs. (17.8 ± 4.1) HU, P < 0.01] post contrast enhancement.

CONCLUSION

CTA could be used to evaluate the severity of the left coronary artery stenosis based on myocardial density measurement. Myocardial delayed enhancement derived from CTA could be used to identify infarct segments.