Table 2.
Univariate analysis of different potential predictors of MHDD (mean heart dose difference) between free-breathing and breath-hold scans.
| Characteristics | rMHDD/MHDD (± SD) | P-Value | |
|---|---|---|---|
| rMHDD | |||
| Age (years) | – | −0.091 | 0.359 |
| BMI (kg/m2) | – | 0.314 | 0.004 |
| Field size (cm2) | – | 0.182 | 0.066 |
| Time Surgery-CT (days) | – | 0.021 | 0.837 |
| MHDD (± SD) | |||
| Smoking | No | 1.19 ± 0.89 | 0.05 |
| Yes | 0.82 ± 0.79 | ||
| Tumor stage | T0 | 0.53 | 0.987 |
| T1 | 0.99 ± 0.95 | ||
| T2 | 0.99 ± 0.74 | ||
| T3 | 0.94 ± 0.93 | ||
| T4 | 0.81 | ||
| Nodal involvement | No | 1.06 ± 0.87 | 0.224 |
| Yes | 0.84 ± 0.85 | ||
| Lung disease | No | 0.97 ± 0.89 | 0.599 |
| Yes | 1.45 | ||
| CHF | No | 0.98 ± 0.89 | 0.993 |
| Yes | 0.98 | ||
| Prior chest surgery | No | 0.98 ± 0.86 | 0.272 |
| Yes | 1.47 ± 0.94 | ||
| Psychiatric disease | No | 1.04 ± 0.94 | 0.639 |
| Yes | 0.81 ± 0.51 | ||
| Surgery type | Lumpectomy | 0.41 ± 0.39 | 0.25 |
| Mastectomy | 0.99 ± 0.87 | ||
| Axillary dissection | No | 0.98 ± 0.87 | 0.972 |
| Yes | 0.99 ± 0.87 | ||
| Chemo | No | 0.99 ± 0.91 | 0.97 |
| Yes | 0.98 ± 0.83 | ||
| Seasons (CT simulation) | Winter | 1.27 ± 0.91 | |
| Spring | 1.22 ± 0.96 | 0.001 | |
| Summer | 0.66 ± 0.68 | ||
| Fall | 0.47 ± 0.45 |
MHDD, Mean heart dose difference between free-breathing and breath-hold scans; rMHDD, Correlation with MHDD; CHF, Cardiac heart failure; CT, Computed Tomography; SD, standard deviation.