Continuum of Preshock to Classic Cardiogenic Shock in the Critical Care Cardiology Trials Network Registry

The prognostic implications of phenotypes along the preshock to cardiogenic shock (CS) continuum remain uncertain.

This study sought to better characterize pre- or early shock and normotensive CS phenotypes and examine outcomes compared to those with conventional CS.

The CCCTN (Critical Care Cardiology Trials Network) is a registry of contemporary cardiac intensive care units. Consecutive admissions (N = 28,703 across 47 sites) meeting specific criteria based on hemodynamic variables, perfusion parameters, and investigator-reported CS were classified into 1 of 4 groups or none: isolated low cardiac output (CO), heart failure with isolated hypotension, normotensive CS, or SCAI (Society of Cardiovascular Angiography and Intervention) stage C CS. Outcomes of interest were in-hospital mortality and incidence of subsequent hypoperfusion among pre- and early shock states.

A total of 2,498 admissions were assigned to the 4 groups with the following distribution: 4.8% isolated low CO, 4.4% isolated hypotension, 12.1% normotensive CS, and 78.7% SCAI stage C CS. Overall in-hospital mortality was 21.3% (95% CI: 19.7%-23.0%), with a gradient across phenotypes (isolated low CO 3.6% [95% CI: 1.0%-9.0%]; isolated hypotension 11.0% [95% CI: 6.9%-16.6%]; normotensive CS 17.0% [95% CI 13.0%-21.8%]; SCAI stage C CS 24.0% [95% CI: 22.1%-26.0%]; global P < 0.001). Among those with an isolated low CO and isolated hypotension on admission, 47 (42.3%) and 56 (30.9%) subsequently developed hypoperfusion.

In a large contemporary registry of cardiac critical illness, there exists a gradient of mortality for phenotypes along the preshock to CS continuum with risk for subsequent worsening of preshock states. These data may inform refinement of CS definitions and severity staging.