Most of the change in stage of cardiogenic shock (CS) occurred within the first 24 hours of presentation, with little change thereafter, according to a study by the Cardiogenic Shock Working Group (CSWG) presented at ESC Congress 2024 in London and simultaneously published in JACC.

Van-Khue Ton, MD, PhD, et al., used the CSWG-modified Society for Cardiovascular Angiography (CSWG-SCAI) staging system to risk stratify the severity of CS and investigate serial changes at 24, 48 and 72 hours and outcomes.

The study, based on the multicenter CSWG registry, included 3,268 patients (mean age 60.3 years; 70.3% men; 67.5% White, 17.7% Black). Of these, 27% had CS complicating acute myocardial infarction (MI-CS) and 57% had heart failure-related CS (HF-CS). At presentation, most patients (50.8%) were in stage D, followed by 18.1% with stage B, 16.2% with stage C and 14.9% for stage E.

Results showed that at 24 hours, most patients had moved to a different CSWG-SCAI stage. The most dynamic stages were B and C, with 54.5% and 50.9% respectively, moving to a worse stage. Among patients who presented with stage D, 86.3% remained there at 24 hours, while in stage E, 53.8% improved to stage D and 35.7% remained the same. Beyond 24 hours, few patients changed stage. Of note, the changes in stage were similar in patients with MI-CS and HF-CS. Looking at mortality, at 24 hours, most surviving patients (70.6%) were in stage D.

Mortality was highest for patients who had moved to, or stayed in, stage E at 24 hours: 71.4% for those who transitioned from stage B, 80% for those from stage C, 62.2% for those from stage D and 59.7% for those who remained in stage E. Mortality and use of temporary mechanical circulatory support was similar in stage E for patients with and without cardiac arrest, but those with cardiac arrest were on less vasoactive drugs overall.

Survivors in stages C, D and E were found to be significantly younger (mean age 60 vs. 72.8 years in stage C, 59.8 vs. 66.6 years in stage D, and 58.3 vs. 64 years in stage E) and have lower lactate levels than nonsurvivors (1.6 vs. 2.5 mmol/L in stage C, 3.2 vs. 5.4 mmol/L in stage D, and 10.1 vs. 12.4 mmol/L in stage E). Stage B survivors had no significant difference in age or lactate level compared with nonsurvivors (61.8 vs. 66.5 years; 2.7 vs. 2.9 mmol/L).

The authors called the lactate finding significant in "confirming that hypoperfusion may be associated with worse outcomes than hypotension and reinforcing the importance of early CS diagnosis." Noting that more than half of patients with stage B CS at baseline progressed in shock severity, they add that further study of these patients is needed to identify predictors of mortality in this population. Along with early recognition of CS, serial assessment may improve risk stratification.

In an accompanying editorial comment, Ann Gage, MD, FACC, writes the study, "deserves commendation."

"It is the most comprehensive study to date of SCAI stage trajectories," Gage adds, and "strengthens the concept of 'the golden day of shock' as the critical period of recognition and treatment of CS."