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.