Table 1.
Patient and Lesion Characteristics According to Quartile of Resistive Reserve Ratio
| Quartile 1 (RRR≥5) | Quartile 2 (RRR 3.5–4.9) | Quartile 3 (RRR 2.5–3.4) | Quartile 4 (RRR<2.5) | P Value | |
|---|---|---|---|---|---|
| Per‐patient analysis (n=1245) | 258 (20.7%) | 356 (28.6%) | 276 (22.2%) | 355 (28.5%) | |
| General characteristics | |||||
| Age, y | 62.17±9.91 | 63.65±10.07 | 65.78±10.36 | 66.79±10.11 | <0.001 |
| Men | 217 (84.1%) | 285 (80.1%) | 195 (70.7%) | 261 (73.5%) | <0.001 |
| BMI, kg/m2 | 24.9±3.7 | 24.9±3.4 | 24.7±3.5 | 24.8±3.6 | 0.701 |
| Clinical presentation | 0.970 | ||||
| Stable ischemic heart disease | 230 (89.1%) | 321 (90.2%) | 246 (89.1%) | 318 (89.6%) | |
| Acute coronary syndrome | 28 (10.9%) | 35 (9.8%) | 30 (10.9%) | 37 (10.4%) | |
| Cardiovascular risk factors | |||||
| Hypertension | 156 (60.5%) | 231 (64.9%) | 180 (65.2%) | 250 (70.4%) | 0.079 |
| Diabetes mellitus | 73 (28.3%) | 107 (30.1%) | 110 (39.9%) | 155 (43.7%) | <0.001 |
| Hypercholesterolemia | 169 (65.5%) | 225 (63.2%) | 176 (63.8%) | 214 (60.3%) | 0.595 |
| Current smoker | 60 (23.3%) | 67 (18.8%) | 53 (19.2%) | 86 (24.2%) | 0.220 |
| Obesity (BMI>25 kg/m2) | 115 (45.5%) | 160 (45.1%) | 119 (44.2%) | 154 (44.6%) | 0.993 |
| Multivessel disease | 77 (29.8%) | 117 (32.9%) | 100 (36.2%) | 141 (39.7%) | 0.060 |
| Per‐vessel analysis (n=1484)a | 323 (21.8%) | 416 (28.0%) | 327 (22.0%) | 418 (28.2%) | |
| Target vessel location | 0.008 | ||||
| LAD | 191 (59.1%) | 270 (64.9%) | 216 (66.1%) | 273 (65.3%) | |
| LCX | 41 (12.7%) | 54 (13.0%) | 52 (15.9%) | 72 (17.2%) | |
| RCA | 91 (28.2%) | 92 (22.1%) | 59 (18.0%) | 73 (17.5%) | |
| Angiographic characteristics | |||||
| Reference diameter | 3.0±0.6 | 2.9±0.6 | 2.9±0.7 | 2.8±0.6 | <0.001 |
| Diameter stenosis, % | 42.9±15.6 | 45.3±16.4 | 45.9±16.4 | 49.5±17.8 | <0.001 |
| Lesion length, mm | 11.7±8.1 | 12.4±8.1 | 12.2±8.3 | 13.7±9.6 | 0.003 |
| Coronary physiologic parameters | |||||
| Resting Pd/Pa | 0.96±0.04 | 0.94±0.05 | 0.93±0.06 | 0.89±0.11 | <0.001 |
| Fractional flow reserve | 0.86±0.08 | 0.84±0.10 | 0.83±0.11 | 0.79±0.13 | <0.001 |
| Coronary flow reserve | 4.8±0.8 | 3.3±0.5 | 2.4±0.4 | 1.5±0.4 | <0.001 |
| Resting Tmn, sec | 1.10±0.45 | 0.90±0.41 | 0.76±0.44 | 0.62±0.44 | <0.001 |
| Hyperemic Tmn, sec | 0.23±0.09 | 0.28±0.13 | 0.33±0.22 | 0.43±0.33 | <0.001 |
| IMR, U | 16.8±7.6 | 19.0±9.2 | 21.8±12.6 | 25.6±19.9 | <0.001 |
| Resistive reserve ratio | 6.2±1.0 | 4.2±0.4 | 3.0±0.3 | 1.9±0.4 | <0.001 |
Values expressed as mean±SD or number (%). BMI indicates body mass index; IMR, index of microcirculatory resistance; LAD, left anterior descending artery; LCX, left circumflex artery; Pa, aortic pressure; Pd, distal coronary pressure; RCA, right coronary artery; and Tmn, mean transit time.
a
Per‐vessel analyses results (P values) were calculated from a generalized estimating equation.