Association between mean hemodynamic variables during the first 24 h and outcomes in cardiogenic shock: identification of clinically relevant thresholds

Abstract

Cardiogenic shock (CS) remains a critical condition with high mortality rates despite advances in treatment. This study aims to comprehensively evaluate both macrocirculatory and tissue perfusion variables over the initial 24 h post-admission to determine their impact on patient prognosis and identify potential hemodynamic thresholds for optimal outcomes. Secondary aims were to explore the correlation between macrocirculatory and tissue perfusion variables. This is a post hoc analysis of data from two prospective studies, OptimaCC (NCT01367743) and MicroShock (NCT03436641), involving only patients with CS. Both studies applied regular assessment of hemodynamic variables at specific time points (admission, 6, 12, and 24 h) to ensure consistency in data collection, enrolling 118 patients between September 2011 and July 2021, with similar inclusion criteria and care processes. The median age of the cohort was 69 years, 59% being male. The primary outcome, 30-day mortality, occurred in 37% of patients. Average macrocirculation variables over the first 24 h of CS such as mean arterial pressure (MAP), cardiac output (CO), cardiac index (CI), and cardiac power index (CPI) were significantly lower in patients meeting the primary outcome. Accordingly, average tissue perfusion variables (ΔPCO2 and ΔPCO2/C(a-v)O2) over the first 24 h of CS were also consistently impaired in patients meeting the primary outcome. The optimal clinically relevant thresholds of the first 24 h time course for poor outcomes, closely approximating the optimal values identified in the analysis, were: mean SAP < 95 mmHg, MAP < 70 mmHg, CO < 3.5 L/min, CI ≤ 1.8 L/min/m2, CPI < 0.27 W/m2, ScvO2 < 70%, ΔPCO2 ≥ 9 mmHg, and ΔPCO2/C(a-v)O2 ≥ 1.5 mmHg/mL. This study is the first to identify critical hemodynamic thresholds, encompassing both macrocirculatory and tissue perfusion variables, within the initial 24 h of CS that are associated with adverse outcomes. The identified thresholds suggest specific hemodynamic targets that may guide resuscitation strategies.