Mechanical and Pharmacological Revascularization Strategies for Prevention of Microvascular Dysfunction in ST-Segment Elevation Myocardial Infarction: Analysis from Index of Microcirculatory Resistance Registry Data
Table 2
Coronary angiography findings and physiological assessment of study population.
Parameter
Total (N = 160)
High IMR (N = 54)
Low IMR (N = 106)
value
Angiographic parameters
Multivessel, n (%)
61 (38.1%)
29 (53.7%)
32 (30.2%)
0.006
Vascular territory, n (%)
LAD
114 (71.2%)
41 (75.9%)
73 (68.9%)
0.454
LCX
14 (8.8%)
6 (11.1%)
8 (7.5%)
0.647
RCA
32 (20.0%)
7 (13.0%)
25 (23.6%)
0.168
Initial TIMI grade, n (%)
TIMI 0–1
100 (62.5%)
39 (72.2%)
61 (57.5%)
0.101
TIMI 2
43 (26.9%)
13 (24.1%)
30 (28.3%)
0.703
TIMI 3
17 (10.6%)
2 (3.7%)
15 (14.2%)
0.079
Final TIMI grade, n (%)
TIMI 2
16 (10.0%)
12 (22.2%)
4 (3.8%)
0.001
TIMI 3
144 (90.0%)
42 (77.8%)
102 (96.2%)
0.001
Final TMPG, n (%)
TMPG 2
45 (28.1%)
27 (50.0%)
18 (17.0%)
<0.001
TMPG 3
112 (70.0%)
25 (46.3%)
87 (82.1%)
<0.001
TIMI thrombus grade, n (%)
0.215
Grade 1
4 (2.5%)
2 (3.7%)
2 (1.9%)
Grade 2
12 (7.5%)
3 (5.6%)
9 (8.5%)
Grade 3
25 (15.6%)
4 (7.4%)
21 (19.8%)
Grade 4
36 (22.5%)
13 (24.1%)
23 (21.7%)
Grade 5
83 (51.9%)
32 (59.3%)
51 (48.1%)
Collateral flow grade, n (%)
0.215
Rentrop 1
115 (71.9%)
41 (75.9%)
74 (69.8%)
Rentrop 2
35 (21.9%)
12 (22.2%)
23 (21.7%)
Rentrop 3
1 (0.6%)
0 (0.0%)
1 (0.9%)
Distal embolization, n (%)
26 (16.2%)
17 (31.5%)
9 (8.5%)
<0.001
No reflow, n (%)
15 (9.4%)
8 (14.8%)
7 (6.6%)
0.162
Physiologic parameters
Pa (hyp), mm Hg
86.0 ± 16.3
84.9 ± 17.4
86.5 ± 15.7
0.564
Pd (hyp), mm Hg
78.5 ± 15.1
78.7 ± 15.7
78.5 ± 14.9
0.915
Tmn at rest, sec
0.5 [0.3–0.8]
0.7 [0.6–1.0]
0.4 [0.3–0.6]
<0.001
Tmn, hyperemia, sec
0.3 [0.2–0.4]
0.6 [0.4–0.8]
0.2 [0.2–0.3]
<0.001
FFR
0.9 [0.9–1.0]
0.9 [0.9–1.0]
0.9 [0.9–1.0]
0.256
CFR
1.6 [1.1–2.4]
1.3 [1.0–1.8]
1.8 [1.2–2.6]
<0.001
IMR, U
22.1 [13.7–34.9]
39.8 [34.9–52.2]
16.5 [12.5–22.1]
<0.001
IMRcorr, U
22.4 [13.9–35.0]
40.2 [34.9–52.2]
16.4 [12.4–22.2]
<0.001
CFR, coronary flow reserve; FFR, fractional flow reserve; Tmn, mean transit time; IMR, index of microcirculatory resistance; IMRcorr, corrected IMR; LAD, left anterior descending artery; LCX, left circumflex artery; MVD, microvascular dysfunction; Pa (hyp), mean aortic pressure during hyperemia; Pd (hyp), mean distal coronary pressure during hyperemia; RCA, right coronary artery; Tmn, mean transit time; TIMI, thrombolysis in myocardial infarction; TMPG, thrombolysis in myocardial infarction myocardial perfusion grade.