Pulmonary Artery Diastolic Pressure as a Surrogate for Pulmonary Capillary Wedge Pressure in Cardiogenic Shock

Background It is common for clinicians to use the pulmonary artery diastolic pressure (PADP) as a surrogate for the pulmonary capillary wedge pressure (PCWP). Here, we determine the validity of this relationship in patients with various phenotypes of cardiogenic shock (CS). Methods and Results In this analysis of the Critical Care Cardiology Trials Network registry, we identified 1,225 admissions with CS that received pulmonary artery catheters. Linear regression, Bland-Altman, and receiver operator characteristic analyses were performed to determine the strength of association between PADP and PCWP in patients with left-, right-, bi-ventricular, and other non-myocardial phenotypes of CS (e.g., arrhythmia, valvular stenosis, tamponade). There was a moderately strong correlation between PADP and PCWP in the total population (r=0.64, n=1225) and in each CS phenotype, except for right ventricular CS for which the correlation was weak (r=0.43, n=71). Additionally, we found that a PADP ≥24 mmHg can be used to infer a PCWP ≥18 mmHg with ≥90% confidence in all but the right ventricular CS phenotype. Conclusions This analysis validates the practice of using PADP as a surrogate for PCWP in most patients with CS, however it should generally be avoided in cases of right ventricular predominant CS.