Objectives: This study compared the prevalence of angiographic underestimation of left anterior descending artery (LAD) lesions with non-LAD lesions.
Background: Coronary angiography cannot assess the functional severity of a coronary stenosis. Previous studies suggested that lesions of the LAD are more often angiographically underestimated, but evidence is limited.
Materials and methods: Fractional flow reserve (FFR) was performed in 335 coronary lesions (187 LAD lesions and 148 non-LAD lesions). A visually estimated diameter stenosis of at least 70% was considered functionally significant. An FFR value of up to 0.80 was considered significant. Multivariable analyses were carried out.
Results: Angiographically, LAD lesions as well as non-LAD lesions were considered functionally significant in 29% (P=0.94). FFR showed significant stenosis of the LAD in 52% compared with 24% in non-LAD lesions (P<0.001). Underestimation was observed in 30% of LAD lesions compared with 11% in non-LAD lesions (P<0.001). The adjusted odds ratio for underestimation in LAD lesions in comparison with non-LAD lesions was 3.48 (95% confidence interval 1.89-6.41; P<0.001).
Conclusion: Underestimation of the functional severity of a coronary stenosis is more common in LAD lesions. FFR should be performed more often for intermediate stenosis of the LAD.