Early lower pulmonary arterial diastolic pressure monitored with pulmonary arterial catheters is associated with improved survival during VA ECMO for patients with acute cardiogenic shock—A propensity matched study

Background

Venoarterial extracorporeal membrane oxygenation (VA ECMO) is used to support refractory cardiogenic shock (CS) but may increase peripheral afterload. Invasive hemodynamic measurement and cardiopulmonary congestion during VA ECMO, may correlate with survival, however, the precise mechanisms underlying this benefit are uncertain.

Objective

To determine whether invasive hemodynamic monitoring with PAC and early on-support pulmonary artery diastolic pressure (PAD) are associated with survival during VA ECMO.

Methods

We analyzed adult patients with CS from the Extracorporeal Life Support Organization Registry from 2015 to 2020. Invasive hemodynamics were assessed at 24 hours of ECMO. The primary outcome was 30-day in-hospital mortality. We examined the association between use of LVMU and both 24-hour on-support invasive hemodynamics and in-hospital mortality, using landmark adjustment.

Results

We identified 7,654 patients treated with VA ECMO for CS, of whom 3,077 were managed with a PAC. PAC use during VA ECMO was not significantly associated with lower in-hospital mortality: adjusted odds ratio (aOR) of death 0.95 (95% CI: 0.897–1.006; p=0.077). Among patients who survived 24 hours, higher single early values of on-support PAD at 24 hours (>18 mmHg) were associated with greater in-hospital mortality within 30 days (HR 1.29 [95% CI 1.13–1.46]; p<0.001), which remained consistent within subgroups receiving concomitant LVMU (pVAD or IABP).

Conclusions

There is a significant, graded relationship between higher single measures of 24-hour on-support PAD and death. Patient survival is greatest when 24 hour PAD is below 18mmHg. PAD decreased at 24 hours among all comers but 47% of patients received LVMU devices to support this reduction.