Abstract
BACKGROUND: Elevated right ventricular systolic pressure (RVSP) is associated with higher mortality in cardiac intensive care unit (CICU) patients. Markers of right ventricular-pulmonary artery (PA) coupling may be superior to RVSP. OBJECTIVES: The authors sought to determine whether effective PA elastance (E(PA), RVSP to stroke volume ratio) and the ratio of pulmonary and systemic elastances (RVSP to systolic blood pressure [SBP] ratio) predicted mortality in a CICU population. METHODS: Mayo Clinic CICU admissions from 2007 to 2018 with available data for E(PA) or RVSP/SBP were included. The primary outcome was in-hospital mortality, and predictors of in-hospital mortality were analyzed using multivariable logistic regression. RESULTS: The included 5,004 unique CICU patients had a median age of 72.2 years; 40.9% were females. The 348 (7.7%) patients who died during hospitalization had higher E(PA) (0.75 vs 0.51) and RVSP/SBP ratio (0.44 vs 0.33). Greater values of E(PA) (adjusted OR: 1.12 per 0.1 higher, 95% CI: 1.09-1.16) and RVSP/SBP (adjusted OR: 1.18 per 0.1 higher, 95% CI: 1.11-1.25) ratios were incrementally associated with higher severity of illness, more comorbidities, and increased in-hospital mortality. One-year mortality was incrementally higher with increasing values of E(PA) (adjusted HR: 1.09 per 0.1 higher, 95% CI: 1.08-1.1) and RVSP/SBP ratio (adjusted HR: 1.09 per 0.1 higher, 95% CI: 1.07-1.1). Both E(PA) and RVSP/SBP ratio had higher discrimination than RVSP alone for predicting in-hospital mortality. CONCLUSIONS: Noninvasive echocardiographic E(PA) and RVSP/SBP ratio can be used to incrementally prognosticate among CICU patients, and these parameters predict mortality better than RVSP alone.