Table 4.
Hazard Ratios with 95% Confidence Intervals for Significant Independent ECG Predictors of Incident Heart Failure in Women with LBBB, RBBB and No BBB
| Reference Quintiles |
Test Quintile Threshold |
Model-1* | Model-2* | Model-3* | |
|---|---|---|---|---|---|
| LBBB (N=680) | |||||
| Heart rate | Q1–4 | Q5=(>75) | 1.94 (1.22–3.09) | 1.84 (1.13–2.98) | 2.01 (1.09–3.70) |
| QRS dur. (ms) | 120–139 | ≥140 | 1.77 (1.12–2.79) | 1.59 (1.00–2.58) | 1.87 (1.01–3.46) |
| RNDVP(µV) | Q1–4 | Q5=(≥107) | 1.83 (1.15–2.93) | 1.64 (1.00–2.70) | 1.89 (1.05–3.41) |
| STJ aVL (µV) | Q2–5 | Q1=(≤−25) | 2.60 (1.67–4.06) | 1.85 (1.10–3.12) | 2.50 (1.35–4.61) |
| Ѳ(QRS|STT)† (°) | Q1–4 | Q5=(≥153) | 2.01 (1.26–3.19) | 1.41 (0.80–2.47) | 1.97 (1.05–3.70) |
| RBBB (N=740) | |||||
| RNDVP(µV) | Q1–4 | Q5=(≥112) | 2.53 (1.24–5.19) | 2.81 (1.16–5.34) | 3.31 (1.09–10.0) |
| QRS dur. (ms) | 120–139 | ≥140 | 1.34 (0.66–2.72) | 1.14 (0.55–2.37) | 1.00 (0.37–2.74) |
| No-Bundle Branch Block at Baseline (N=64,299) | |||||
| Heart rate | Q1–4 | Q5=(≥75) | 1.78 (1.58–1.99) | 1.52 (1.35–1.70) | 1.26 (1.10–1.44) |
| QRS dur. (ms) | Q1–4 | Q5=(≥95) | 1.64 (1.46–1.84) | 1.29 (1.14–1.46) | 1.12 (0.97–1.28) |
| QTrr# (ms) | Q1–4 | Q5=(>427) | 1.80 (1.61–2.01) | 1.36 (1.21–1.53) | 1.29 (1.14–1.47) |
| Ѳ(QRS|STT)† (°) | Q1–4 | Q5=(≥63) | 2.79 (2.51–3.10) | 1.52 (1.33–1.73) | 1.36 (1.18–1.58) |
| RNDVP(µV) | Q1–4 | Q5=(≥53) | 1.46 (1.29–1.64) | 1.28 (1.13–1.44) | 1.27 (1.11–1.46) |
| STJ aVR (µV) | Q1–4 | Q5=(>0) | 2.02 (1.80–2.26) | 1.35 (1.17–1.57) | 1.40 (1.18–1.65) |
| TaVL (µV) | Q2–5 | Q1=(≤0) | 2.17 (1.95–2.42) | 1.22 (1.08–1.38) | 1.23 (1.06–1.41) |
Model-1: Unadjusted single ECG variable risk model (included heart rate, QRS duration, QTrr, Ѳ(QRS|STT), RNDVP, ST amplitude at J-point in leads of aVR, aVL, V1 and V6, and T wave amplitude in the leads of aVR, aVL, V1 and V6, separately); Model-2:Significant predictors in Model-1 entered simultaneously and each adjusted for the other ECG covariates; Model-3:ECG variables in Model-2 entered simultaneously and adjusted for demographic and clinical factors listed in the footnote of Table 2.
Ѳ(QRS|STT)= spatial angle between the mean QRS and ST-T vectors.
QTrr = rate adjusted QT using formulas listed in the footnote of Table 1.