Evaluation of Changes in Coronary Ischemia After Lipid-Lowering Therapy Using Computed Tomography Angiography

A 67-year-old man who had been taking azilsartan 20 mg/day and eicosapentaenoic acid 1.8 g/day presented with atypical chest pain and underwent coronary computed tomography angiography (CCTA) to assess coronary artery disease as described in the Supplementary Methods. CCTA showed a 50–69% stenosis with low-density plaques in the proximal left anterior descending artery (Figure A; Supplementary Figure). Fractional flow reserve on CCTA (FFR_CT), measured approximately 2 cm distal to the stenosis, indicated positive ischemia (Figure C). Furthermore, the difference in FFR_CT values proximal and distal to the lesion (∆FFR_CT) was 0.21 (Figure C). At the 2-year follow-up after starting rosuvastatin 5 mg/day, low-density lipoprotein concentrations had decreased from 146 to 56 mg/dL with subsequent improvement in symptoms. CCTA showed an improvement in distal FFR_CT and ∆FFR_CT from 0.76 to 0.88 and from 0.21 to 0.09, respectively (Figure D), and a mild improvement in the stenosis with an increase in density (Figure B; Supplementary Figure).

Figure.

(A,B) Stretched views show moderate stenosis at the middle of the left anterior descending artery (arrow) at baseline (A) and follow-up (B). (C,D) Three-dimensional model showing fractional flow reserve derived from coronary computed tomography angiography (FFR_CT) values at baseline (C) and follow-up (D).

This case demonstrates the usefulness of FFR_CT for evaluation of coronary ischemia after lipid-lowering therapy. FFR_CT predicts lesion-specific ischemia compared with invasive FFR. Patients with distal FFR_CT >0.8 have a better prognosis.¹ A study also demonstrated that greater ∆FFR_CT is associated with an increase in cardiovascular events.² Our patient’s distal FFR_CT and ∆FFR_CT improved after lipid-lowering therapy, suggesting the usefulness of FFR_CT for clinically assessing improvement in coronary ischemia with lipid-lowering therapy.

Supplementary Files

Please find supplementary file(s);

https://doi.org/10.1253/circrep.CR-23-0091

References

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• 2.   Nozaki YO, Fujimoto S, Kawaguchi YO, Aoshima C, Kamo Y, Sato H, et al. Prognostic value of the optimal measurement location of on-site CT-derived fractional flow reserve. J Cardiol 2022; 80: 14–21.