Elsevier

American Heart Journal

Volume 150, Issue 2, August 2005, Pages 338-343
American Heart Journal

Clinical Investigation
Interventional Cardiology
Effect of lesion length on fractional flow reserve in intermediate coronary lesions

https://doi.org/10.1016/j.ahj.2004.09.007Get rights and content

Background

Fractional flow reserve (FFR) has become a gold standard in physiological assessment of coronary artery stenosis. An FFR <0.75 is considered as a reliable physiological parameter indicating functionally significant lesion. Lesion length (LL) may affect the translesional hemodynamics. However, the effect of LL on FFR has not been adequately assessed. We sought to evaluate the effect of LL on FFR in patients with angiographically intermediate coronary artery disease.

Methods

We performed FFR measurements by pressure guidewire in 63 intermediate-grade lesions (63 patients) by visual assessment. Lesion length and percent diameter stenosis (%DS) at the lesion site were determined by performing off-line quantitative coronary angiography analysis.

Results

Overall, there was a moderate inverse correlation between FFR and %DS (r = −0.55, P < .001). In addition, there was a weak inverse correlation between LL and FFR (r = −0.31, P < .001). Using a receiver operating characteristic curve analysis, an LL ≥10 mm was identified as the best cutoff value for predicting an FFR <0.75 (sensitivity 95%, specificity 66%, positive predictive power 48%, and negative predictive power 97%). The correlation between FFR and %DS was significantly improved for LL ≥10 mm, as compared with LL <10 mm (r = −0.78, P < .001; r = 0.16, P = NS; respectively). Similar improvement with LL was also observed for intermediate lesions by quantitative coronary angiography (%DS 50%-70%; r = 0.19, P = NS for LL <10 mm; r = −0.74, P < .001 for LL ≥10 mm).

Conclusions

This study demonstrates that LL differentially affects the correlation between the functional assessment (FFR) and the “anatomic” severity (%DS) of coronary lesions and suggests that LL has a significant impact on the physiological significance of intermediate-grade coronary lesions.

Section snippets

Patients population

The study population consisted of 63 consecutive patients (63 lesions) with stable angina who were referred for coronary angiography and were found to have intermediate coronary lesions (40% to 70% DS by angiographic visual assessment). All patients underwent physiological lesion assessment by IC pressure measurements and FFR determination. Exclusion criteria included unstable angina, left ventricular ejection fraction below 40%, significant left main disease (stenosis >50%); multiple lesions

Results

The study patients (n = 63) were mostly men (71%), with a mean (±SD) age of 62 ± 13 (range 45-83) years. The demographic and clinical characteristics of the patients are outlined in Table I. The baseline angiographic and physiological characteristics of the assessed lesions are outlined in Table II. The assessed vessel was the left anterior descending in 32 (51%) of the lesions, left circumflex in 14 (22%) of the lesions, RCA in 14 (22%) of the lesions, and vein graft in 3 (5%) of the lesions.

Discussion

The current study demonstrates that LL may differentially affect the relationship between the anatomic and physiological parameters that describe coronary stenosis severity. Our results may explain the previously observed lack of correlation between angiographic and physiological coronary lesion severity. A categorized cutoff LL value of 10 mm was identified as a sensitive predicting index for a categorized cutoff FFR value of 0.75. By dividing the lesions into 2 subgroups above and below the

References (26)

  • K.A. Eagle et al.

    ACC/AHA guidelines for coronary artery bypass graft surgery: executive summary and recommendations: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines

    Circulation

    (1999)
  • B. de Bruyne et al.

    Simultaneous coronary pressure and flow velocity measurements in humans. Feasibility, reproducibility, and hemodynamic dependence of coronary flow velocity reserve, hyperemic flow versus pressure slope index, and fractional flow reserve

    Circulation

    (1996)
  • N.H. Pijls et al.

    Fractional flow reserve. A useful index to evaluate the influence of an epicardial coronary stenosis on myocardial blood flow

    Circulation

    (1995)
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