Table 3.
Multiple logistic regression model based on ECG and other clinical characteristics of patients (n = 627a) who come to the emergency department with acute chest pain and acute coronary syndrome (ACS). I-STamp, ST amplitude in lead I; aVF-STamp, ST amplitude in lead aVF; V2-STamp, ST amplitude in lead V2; STamp38, ST amplitude at the end of the third out of eight equal intervals between the ST-J point and the end of the T wave.
| Estimate | 95% CI | |
| Baseline odds for ACSb | 0.0163 | 0.0073 – 0.0362 |
| Odds ratios | ||
| Age (no. of years above 40) | 1.031 | 1.014 – 1.047 |
| Hypertension | 1.7 | 1.1 – 2.8 |
| Angina pectoris ≤ 1 month | 4.1 | 0.97 – 17 |
| Congestive heart failure | 0.48 | 0.24 – 0.94 |
| Previous myocardial infarction | ||
| Yes, ≤ 6 months | 2.7 | 1.2 – 6.4 |
| Yes, > 6 months | 2.1 | 1.2 – 3.8 |
| No | 1.0 | - |
| Previous CABG | 0.23 | 0.09 – 0.60 |
| Chest discomfort at presentation | 1.9 | 1.2 – 3.1 |
| Symptom duration | ||
| 0 – 6 h | 3.8 | 2.0 – 7.1 |
| 7 – 12 h | 2.8 | 1.2 – 6.5 |
| > 12 h | 1.0 | - |
| I-Stamp | ||
| I-STamp > 50 and I-STamp38 > I-Stamp | 2.4 | 0.74 – 7.7 |
| aVF-Stamp | ||
| aVF-STamp>100 and aVF-STamp38>aVF-Stamp | 9.4 | 2.7 – 33 |
| aVF-STamp < -100 and aVF-STamp38 < aVF-STamp | 4.1 | 0.72 – 23 |
| None of above | 1.0 | |
| V2-Stamp | ||
| V2-STamp > 200 and V2-STamp38 > V2-Stamp | 3.4 | 1.5 – 7.4 |
| 100 < V2-STamp ≤ 200 and V2-STamp38 > V2-STamp | 1.6 | 0.90 – 2.8 |
| V2-STamp < -100 and V2-STamp38 < V2-Stamp | 2.6 | 0.54 – 13 |
| None of above | 1.0 | - |
a Data on at least one of characteristics were missing for 7 (4 with ACS and 3 without ACS) of the original 634 patients.
b Baseline odds for ACS for a 40-year old patient who belongs to the reference category with respect to all other characteristics. The corresponding risk (probability) for ACS can be calculated as Odds/(1+Odds).