A56-28 Dynamic Ventricular-arterial Coupling Phenotypes Identify Early Recovery and Deterioration in Septic Shock

Rationale Septic shock is characterized by highly variable cardiovascular responses despite standardized resuscitation. Ventricular-arterial coupling (VAC), defined as the ratio of arterial elastance (Ea) to left ventricular end-systolic elastance (Ees), may reveal clinically meaningful trajectories not captured by conventional metrics (e.g., cardiac output). We sought to identify phenotypes of early changes in VAC and organ dysfunction in septic shock. Methods We conducted a prospective cohort study of adult patients with septic shock admitted to a single intensive care unit within 48 hours of diagnosis. VAC was computed using the Chen single-beat method from echocardiographic and bedside hemodynamic measurements. VAC and Sequential Organ Failure Assessment (SOFA) score were assessed at 24 and 48 hours after ICU admission. Changes were defined as ΔVAC and ΔSOFA (48h-24h). Principal component analysis (PCA) and k-means clustering were used to identify phenotypes based on ΔVAC and ΔSOFA. Results Among 116 patients, PCA-based k-means clustering identified three phenotypes: progressive dysfunction (n = 38), stable(n = 18), and recovery (n = 60). In progressive dysfunction, VAC increased from 1.5 (IQR 1.3-2.1) to 2.0 (IQR 1.5-2.7) and SOFA increased from 6.0 (IQR 4.2-7.0) to 7.5 (IQR 6.0-8.8) (both p < 0.05). In the stable phenotype, VAC (1.4 to 1.6) and SOFA (6.0 to 7.0) did not change significantly (p = 0.15 and p = 0.11, respectively). In recovery, VAC decreased from 1.7 (IQR 1.3-2.3) to 1.5 (IQR 1.2-1.9) and SOFA decreased from 8.0 (IQR 6.0-10.0) to 6.0 (IQR 5.0-7.3) (both p < 0.05). Conclusions Early septic shock exhibits distinct VAC-SOFA dynamic phenotypes, highlighting heterogeneity in cardiovascular efficiency and organ dysfunction trajectories. VAC monitoring may provide actionable physiologic information beyond conventional hemodynamic variables and support personalized resuscitation strategies. Funding source None.