Exercise oscillatory ventilation in patients with advanced heart failure with and without left ventricular assist device

Background Exercise oscillatory ventilation (EOV), indicating pathological fluctuations on pulmonary arterial pressure, is associated with mortality in patients with heart failure (HF). Whether left ventricular assist device (LVAD)-induced ventricular unloading can reverse EOV and may prevent short-term rehospitalization has not been investigated. Methods We performed a retrospective single-center in- and outpatient analysis of patients with (n = 20, LVAD) and without (n = 27, HF) circulatory support and reduced ejection fraction (EF, 22.8 +/- 7.9%). The association of cardiopulmonary exercise testing (CPET) variables and 3 months-rehospitalization (3MR) as a primary outcome was analyzed. Furthermore, CPET variables were compared regarding the presence of EOV (+/-). Results Lower VO2peak (11.6 +/- 4.9 ml/kg/min vs. 14.4 +/- 4.3 ml/kg/min, p = 0.039), lower increase of PETCO2 (CI = 0.049-1.127; p = 0.068), and higher VE/VCO2 (43.8 +/- 9.5 vs. 38.3 +/- 10.6; p = 0.069) were associated with 3MR. Flattening of O-2 pulse (CI = 0.139-2.379; p = 0.487) had no impact on 3MR. EOV was present in 59.5% (n = 28/47) of patients, without a significant difference between LVAD and HF patients (p = 0.959). Patients with HF/EOV+ demonstrated significantly lower VO2peak compared with HF/EOV- (p = 0.039). LVAD/EOV+ displayed significantly lower EF (p = 0.004) and fewer aortic valve opening than LVAD/EOV- (p = 0.027). Conclusions Lower VO2peak, but not EOV, was associated with 3MR. EOV occurred at a similar rate in LVAD and HF patients, which may illustrate insufficient unloading during exercise in chronic LVAD therapy and may contribute to the limited exercise capacity following LVAD implantation. Simultaneous CPET and right heart catheterization studies are needed to elucidate whether EOV may serve as a non-invasive predictor of insufficient LV unloading necessitating LVAD reprograming.

Automated summary

The aim of this study was to investigate whether left ventricular assist device (LVAD) can reverse exercise oscillatory ventilation (EOV) in patients with heart failure and prevent short-term rehospitalization. The results showed that lower maximal oxygen consumption (VO2peak) was associated with rehospitalization, and the occurrence rate of EOV was similar in LVAD and heart failure patients. This may indicate insufficient unloading during exercise in chronic LVAD therapy and limited exercise capacity following LVAD implantation. Further studies are needed to determine whether EOV can serve as a non-invasive predictor of insufficient LV unloading and necessitating LVAD reprograming.