Burstein, Barry

Background: Reduced left ventricular stroke work index (LVSWI) has been associated with adverse outcomes in several populations of patients with chronic heart disease, but no prior studies have examined this metric in cardiac intensive care unit (CICU) patients. We sought to determine whether a low LVSWI, as measured noninvasively using transthoracic echocardiography, is associated with higher mortality in CICU patients. Methods: Using a database of unique Mayo Clinic CICU admissions from 2007 to 2018, we identified patients with LVSWI measured by transthoracic echocardiography within 1 day of CICU admission. Hospital mortality was analyzed using multivariable logistic regression, and 1-year mortality was analyzed using multivariable Cox proportional-hazards analysis, adjusted for left ventricular ejection fraction and known predictors of hospital mortality. Results: We included 4536 patients with a mean age of 68±14 years (36% women). Admission diagnoses (not mutually exclusive) included acute coronary syndrome in 62%, heart failure in 46%, and cardiogenic shock in 11%. The mean LVSWI was 38±14 g×min/m 2 , and in-hospital mortality occurred in 6% of patients. LVSWI had better discrimination for hospital mortality than left ventricular ejection fraction ( P <0.001 by De Long test). Higher LVSWI was associated with lower in-hospital mortality (adjusted odds ratio, 0.72 per 10 g×min/m 2 higher [95% CI, 0.61–0.84]; P <0.001) and lower 1-year mortality (adjusted hazard ratio, 0.812 per 1 g×min/m 2 higher [95% CI, 0.759–0.868]; P <0.001). Stepwise decreases in hospital and 1-year mortality were observed with higher LVSWI. Conclusions: Low LVSWI, reflecting poor left ventricular systolic and diastolic performance, is associated with increased short-term and long-term mortality among CICU patients. This emphasizes the importance of Doppler transthoracic echocardiography as a predictor of outcomes among critically ill patients. Further study is required to determine whether early interventions to optimize LVSWI can improve outcomes in the CICU setting.

ABSTRACT Background: Shock in patients resuscitated after out of hospital cardiac arrest (OHCA) is associated with an increased risk of mortality. We sought to determine the associations between lactate level, mean arterial pressure (MAP), and vasopressor/inotrope doses with mortality. Methods: Retrospective cohort study of adult patients with OHCA of presumed cardiac etiology treated with targeted temperature management (TTM) between December 2005 and September 2016. Multivariable logistic regression was performed to determine predictors of hospital death. Results: Among 268 included patients, the median age was 64 (55, 71.8) years, including 27% females. OHCA was witnessed in 89%, OHCA rhythm was shockable in 87%, and bystander CPR was provided in 64%. Vasopressors were required during the first 24 h in 60%. Hospital mortality occurred in 104 (38.8%) patients. Higher initial lactate, peak Vasoactive-Inotropic Score (VIS), and lower mean 24-h MAP were associated with higher hospital mortality (all P < 0.001). After multivariable regression, both higher initial lactate (adjusted OR 1.15 per 1 mmol/L higher, 95% CI 1.00–1.31, P = 0.03) and higher peak VIS (adjusted OR 1.20 per 10 units higher, 95% CI 1.10–1.54, P = 0.003) were associated with higher hospital mortality, but mMAP was not (P = 0.92). However, patients with a mMAP < 70 mm Hg remained at higher risk of hospital mortality after multivariable adjustment (adjusted OR 9.30, 95% CI 1.39–62.02, P = 0.02). Conclusions: In patients treated with TTM after OHCA, greater shock severity, as reflected by higher lactate levels, mMAP < 70 mmHg, and higher vasopressor requirements during the first 24 h was associated with an increased rate of hospital mortality.

ABSTRACT Background: Lactate is a prognostic marker in critically ill patients, although currently available illness severity scores do not include lactate as a predictive parameter. We sought to describe the association between lactate and hospital mortality in patients admitted to the cardiac intensive care unit (CICU) with cardiac arrest (CA) and shock. Methods: Retrospective observational analysis of Mayo Clinic CICU patients admitted from 2007 to 2018 with measured lactate on admission, including patients with and without CA or shock. We examined hospital mortality as a function of admission lactate in patients. Multivariable logistic regression was used to determine predictors of hospital mortality. Results: We included 3,042 patients with a median age of 70 years (IQR 60–80), including 41% females, 26% with CA, and 39% with shock. The median APACHE-IV predicted mortality was 24% (IQR 11–51%), and the median admission lactate was 1.8 mmol/L (IQR 1.1–3.0). Hospital mortality occurred in 23% of patients and rose progressively with higher admission lactate, including in patients with and without CA or shock. After multivariable adjustment for clinical characteristics, therapies, and illness severity, a higher lactate remained associated with increased hospital mortality (adjusted OR 1.13 per mmol/L, 95% CI 1.06–1.20, P < 0.001). Conclusions: Admission lactate levels are strongly associated with increased hospital mortality among CICU patients, including those with and without CA or shock. The prognostic value of lactate levels is independent of established ICU prognostic scores and dependent on admission diagnosis, which may help inform clinicians caring for CICU patients.