Table 1.
Clinical Characteristics of Patients in the Overall Population and When Classified According to the Index TMR
| Variable | Overall Population (n=651) | TMR <0.040 (n=340) | TMR ≥0.040 (n=311) | P Value |
|---|---|---|---|---|
| Clinical variables | ||||
| Age, y | 64 (17) | 63 (18) | 66 (17) | 0.155 |
| Sex (male) | 464 (71%) | 263 (77%) | 201 (65%) | <0.001a |
| NYHA class III | 115 (18%) | 62 (18%) | 53 (17%) | 0.758 |
| LVEF ≤35% | 356 (55%) | 190 (56%) | 166 (53%) | 0.529 |
| Ischemic etiology | 327 (50%) | 153 (45%) | 174 (56%) | 0.006a |
| Diabetes mellitus | 244 (38%) | 119 (35%) | 125 (40%) | 0.195 |
| β‐Blockers | 455 (70%) | 237 (70%) | 218 (70%) | 0.932 |
| Amiodarone | 61 (9%) | 27 (8%) | 34 (11%) | 0.226 |
| ARB or ACE inhibitors | 576 (89%) | 303 (89%) | 273 (88%) | 0.624 |
| ECG variables | ||||
| Median RR, s | 0.86 (0.18) | 0.86 (0.17) | 0.84 (0.21) | 0.027a |
| RR range, s | 0.42 (0.22) | 0.45 (0.20) | 0.37 (0.21) | <0.001a |
| QRS >120 ms | 262 (40%) | 152 (45%) | 110 (35%) | 0.016a |
| NSVT and more than 240 VPB in 24‐h | 168 (26%) | 87 (26%) | 81 (26%) | 0.929 |
| IAA ≥3.7 μV | 153 (24%) | 74 (22%) | 79 (25%) | 0.309 |
| TS ≤2.5 ms/RR | 281 (47%) | 125 (40%) | 156 (55%) | <0.001a |
| T‐wave restitution parameters | ||||
| ΔαTpe | 0.025 (0.03) | 0.020 (0.03) | 0.032 (0.04) | <0.001a |
| ΔαQT | 0.199 (0.10) | 0.188 (0.08) | 0.215 (0.10) | <0.001a |
Data are represented as median (interquartile range) for continuous variables and as number (percentage) for dichotomized variables. ACE indicates angiotensin‐converting enzyme; ARB, angiotensin receptor blocker; ECG, electrocardiogram; IAA, index of average alternans; LVEF, left ventricular ejection fraction; NSVT, nonsustained ventricular tachycardia; NYHA, New York Heart Association; TMR, T‐wave morphology restitution; TS, turbulence slope; VPB, ventricular premature beat.
a
Indicates statistical differences.