Non-invasive mechanical ventilation reduces cardiorespiratory motion and increases heart-stomach distance for stereotactic arrhythmia radiotherapy: a healthy volunteer study.

BACKGROUND: on cardiorespiratory motion of the left diaphragm and the minimal heart-stomach distance. METHODS: . Encompassing volumes of the heart and stomach were generated from BH-inhalation and BH-exhalation scans to evaluate overlap or separation during free-breathing. Lastly, cine frames were deformably registered to assess temporal heart-stomach distance variation. RESULTS: , significantly larger than during BH-inhalation (10.3 mm, p=0.04) and BH-exhalation (4.6 mm, p<0.01). Whereas analysis emulating free-breathing showed frequent heart and stomach internal-volume overlap (27/41 sessions) or minimal median distance of 3.4 mm (IQR: 7 mm) between the heart and stomach, which can result in significant stomach dose during STAR. Median temporal heart-stomach distance was 19.2 mm during NIMV60P versus 7.1 mm free-breathing. CONCLUSIONS: significantly reduces diaphragm motion and increases the distance between heart and stomach in healthy volunteers, supporting its integration with STAR to potentially improve targeting and reduce stomach toxicity, especially for inferior wall VT targets.