High left ventricular mass index does not limit the utility of fractional flow reserve for the physiologic assessment of lesion severity.

OBJECTIVES: To demonstrate that fractional flow reserve (FFR) of vessels in patients with high left ventricular mass index (LVMI) should be similar to that of matched vessels in patients with normal LVMI. BACKGROUND: FFR is a physiologic index of coronary lesion severity. It is not known whether FFR remains useful in the setting of increased LVMI, when microvascular abnormalities may be present. METHODS: LVMI was calculated in 84 patients using contrast left ventriculography after validation with cardiac magnetic resonance imaging. Cardiac risk factors, LV ejection fraction (LVEF), minimal lumen diameter (MLD), percent diameter stenosis (%DS), lesion length and FFR were compared in 22 patients with high LVMI to 62 patients with normal LVMI and angiographically-matched vessels. RESULTS: LVMI was 126 +/- 21 g/m2 in the high LVMI group and 84 +/- 21 g/m2 in the normal LVMI group. There were no differences in age, LVEF, diabetes, hypertension or dyslipidemia between groups. Angiographic lesion characteristics were well matched in patients with high versus normal LVMI (MLD 1.3 +/- 0.6 mm vs. 1.3 +/- 0.6 mm, %DS 61 +/- 13% vs. 62 +/- 13%, and lesion length 14.2 +/- 7.0 mm vs. 14.3 +/- 7.0 mm; p = NS for all). Importantly, no difference in FFR was observed (0.79 +/- 0.12 vs. 0.78 +/- 0.16; p = NS) between the groups, and LVMI did not correlate with FFR in a multivariate analysis. CONCLUSIONS: FFR of coronary lesions in patients with high LVMI is no different than FFR of angiographically-matched lesions in patients with normal LVMI, suggesting that high LV mass should not limit the utility of FFR as an index of coronary lesion severity.