Deterioration of cardiogenic shock after acute myocardial infarction defined by the society for cardiovascular angiography and intervention cardiogenic shock classification scheme
Authors: Mukaida T , Kataoka Y , Murai Y , Iwai T , Sawada K , Matama H , Honda S , Takagi K , Fujino M , Yoneda S , Otsuka F , Tahara Y , Asaumi Y , Noguchi T 
Published: October 2022

Abstract

Background
Cardiogenic shock (CS) in patients with AMI presents worse cardiovascular outcomes, which suggests the need for better risk stratification and management. The Society for Cardiovascular Angiography and Intervention (SCAI) has recently proposed CS classification scheme, which stratifies CS into 5 groups according to hypotension and hypoperfusion. While stage A and B exhibits CS without hypotension and/or hypoperfusion, their clinical condition could rapidly deteriorate into stage C-E. However, clinical characteristics and in-hospital outcomes of CS exhibiting its deterioration remains uncertain.

Purpose
To characterize AMI patients who deteriorated their CS status from stage A and B into stage C-E.

Methods
This single-center observational study included 326 consecutive AMI patients receiving primary PCI who presented CS stage A and B on arrival (2019.09.01–2021.09.30). Deterioration of CS (D-CS) was defined as the progression from stage A and B on arrival to stage C-E after primary PCI. Clinical characteristics and outcomes were compared in those with and without D-CS.

Results
D-CS was identified in 16.0% of entire subjects (=52/326). Of these, 94.2 and 5.8% of them exhibited stage C and E, respectively (Figure). Patients with D-CS more likely presented STEMI (84.6 vs. 67.9%, p=0.01) with a lower systolic BP (sBP) level (130±31 vs. 148±26mmHg, p&lt;0.001) and a reduced LVEF (43±13 vs. 51±9%, p&lt;0.001), whereas there was no significant difference in lactate level (1.5±0.4 vs. 1.2±0.3 mmol/L, p=0.22). Pre-TIMI flow grade 0–1 (69.2 vs. 47.8%, p=0.006), left main trunk stenosis (9.6 vs. 1.5%, p=0.007) and chronic total occlusion (21.2 vs. 8.4%, p=0.01) were more frequently observed in those with D-CS. Despite achieving a shorter onset-to-reperfusion time (199 vs. 276 minutes, p=0.002), D-CS was associated with in-hospital all-cause mortality after adjusting clinical characteristics (HR=33.6, 95% CI: 2.2–502.0, p=0.01). Furthermore, mechanical circulatory support (MCS) (30.8 vs. 0%, p&lt;0.001) was more frequently required in patients with D-CS (IABP: 28.8 vs. 0%, p&lt;0.001, ECMO: 11.5 vs. 0%, p&lt;0.001, Impella: 3.8 vs. 0%, p=0.02). Further analysis identified sBP (HR=0.98, 95% CI: 0.97–1.00, p=0.008), LVEF (HR=0.94, 95% CI: 0.90–0.97, p&lt;0.001) and pre-TIMI flow grade 0–1 (HR=0.41, 95% CI: 0.19–0.86, p=0.01) as independent contributors to D-CS. ROC analysis demonstrated sBP &lt;135 mmHg (AUC=0.65) and LVEF &lt;50% (AUC=0.69) as best cut-off values to predict D-CS. Of note, a risk of D-CS increased in association with the number of these three factors (p&lt;0.001), and 44.0% of those with all of these factors presented D-CS (Figure).

Conclusion
16.0% of AMI without any hypotension/hypoperfusion on arrival exhibited deterioration of CS status on SCAI classification. The combination of sBP, LVEF and pre-TIMI flow grade could help to identify AMI subjects with a risk of D-CS, who may benefit from early adoption of intensified management including MCS prior to PCI.

Funding Acknowledgement
Type of funding sources: None.