Exploring the utility of the CSWG SCAI classification in patients with HF-CS requiring inotropic therapy

Abstract

Abstract Funding Acknowledgements None. Background The Society for Cardiovascular Angiography and Interventions (SCAI) classification has been a well-established tool for risk stratification in heart failure cardiogenic shock (HF-CS). The recent CSWG SCAI classification provides easily obtainable parameters to classify CS severity. However, its utility has been mostly investigated in an intensive care unit (ICU) setting. Therefore, data on a more broad cohort of patients in whom inotropic therapy is deemed necessary is lacking. Purpose This study aimed to analyze the trajectory of patients necessitating inotropic therapy due to HF-CS and the utility of the proposed CSWG SCAI criteria in time. Methods We retrospectively analyzed patients admitted with acute HF who received inotropic therapy due to developing HF-CS at any time during admission. Patients with out-of-hospital cardiac arrest and acute coronary syndrome were excluded. SCAI stages were assigned retrospectively using the latest CSWG SCAI criteria during admission, pre-inotropic therapy, and at worst SCAI. The diagnostic performance of the CSWG SCAI criteria for predicting mortality during admission was assessed. Results This study included 333 patients with HF-CS. Of these patients, 221 (66%) were male, with a mean age of 70 years. The majority of patients were admitted with SCAI A (45%) and B (36%), and inotropic therapy was most often initiated in SCAI stage B (46%). Notably, 21% patient of the patients at time of inotropic therapy were still in SCAI A. In 52% of all patients inotropes was initiated within 24 hours of admission. The most frequently observed worst SCAI classification was C (41%). Lactate and blood pressure (BP) were responsible for the majority of SCAI B-D classifications at admission and pre-inotropic therapy, while pH was an important determent for SCAI E. However, vasoactive therapy was the most common determent for worst SCAI (71%), followed by BP (24%). Mortality rates for pre-inotropic therapy SCAI for classes A-E were 30%, 39%, 47%, 55%, and 48%. Mortality rates for worst SCAI C-E were 29%, 39%, and 59%. The area under the curve for predicting mortality was higher for worst SCAI as compared to pre-inotropic therapy SCAI (0.633 vs. 0.573, p=0.03). There was no difference in mortality between early (<24h) vs. late (>24h) initiation of inotropic therapy (p=0.43). Conclusion In our study the CSWG SCAI criteria proved to be challenging to apply in patients in whom inotropic therapy is considered, especially for patients classified as SCAI E. However, improvement of the CSWG SCAI performance was observed when it was applied at the time corresponding to the worst SCAI stage to predict mortality. More studies are required to further optimize the SCAI criteria in this specific subset of patients. In summary, our study provides valuable insights into the application of the CSWG SCAI classification in a diverse HF-CS population, specifically those requiring inotropic therapy.