Angiographic underestimation of disease severity in the left anterior descending artery: a fractional flow reserve analysis.

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.