Changes in Index of Microcirculatory Resistance during PCI in the Left Anterior Descending Coronary Artery in Relation to Total Length of Implanted Stents
Table 3
Flow indices in relation to total stent length in LAD.
Total stent length in LAD
12–22 mm n = 14
23–37 mm n = 14
38–78 mm n = 14
Before PCI
Pa hyperaemia (mm Hg)
82 (65–84)
76 (61–87)
72 (65–88)
0.903
Pd hyperaemia (mm Hg)
58 (45–65)
50.5 (40–67)
49 (41–56)
0.242
FFR
0.77 (0.69–0.80)
0.74 (0.7–0.77)
0.66 (0.46–0.74)
0.002
IMR†
20 (11–27)
16 (9–26)
16 (10–20)
0.557
IMRcorr†
19 (10–25)
14 (8–24)
14 (10–18)
0.329
CFR
2.95 (2.5–3.8)
2.8 (1.5–4.1)
2.15 (1.2–3.8)
0.305
Tmn baseline (seconds)†
1.0 (0.65–1.49)
0.72 (0.47–1.37)
0.89 (0.63–1.13)
0.305
Tmn hyperaemia (seconds)†
0.32 (0.23–0.54)
0.44 (0.2–0.5)
0.32 (0.24–0.42)
0.750
After PCI
Pa hyperaemia (mm Hg)
72 (64–81)
71 (57–84)
72 (65–80)
0.794
Pd hyperaemia (mm Hg)
64 (55–69)
62 (48–73)
65 (52–72)
0.884
FFR
0.86 (0.84–0.9)
0.84 (0.82–0.87)
0.86 (0.8–0.9)
0.660
IMR†
14 (10–17)
15 (9–23)
22 (14–26)
0.118
IMRcorr†
13 (10–17)
14 (9–22)
21 (13–25)
0.060
CFR
3.6 (2.5–4.9)
3.0 (2–4.7)
2.3 (1.5–4.0)
0.072
Tmn baseline (seconds)†
0.85 (0.58–1.31)
0.61 (0.55–0.88)
0.72 (0.52–1.22)
0.824
Tmn hyperaemia (seconds)†
0.20 (0.17–0.3)
0.21 (0.17–0.36)
0.32 (0.26–0.34)
0.045
Median (interquartile range); CFR = coronary flow reserve; FFR = fractional flow reserve; IMR = index of microcirculatory resistance; IMRcorr = corrected IMR; Pa = arterial pressure during hyperaemia; Pd = distal pressure during hyperaemia; Tmn = mean transit time; linear regression; †variables log-transformed before analysis.