Serial assessment of modified Society for Cardiovascular Angiography and Interventions SHOCK classification in post-cardiotomy patients

BACKGROUND AND AIMS: Post-cardiotomy shock (PCS) is a severe complication after cardiac surgery, associated with high in-hospital mortality. The Society for Cardiovascular Angiography and Interventions (SCAI) SHOCK classification offers a valid approach for initial shock staging post-surgery. However, the prognostic value and accuracy of serial staging remain unclear. The aim of this study is to externally validate the prognostic value and accuracy of serial SCAI SHOCK reclassification for all-cause in-hospital mortality in PCS patients during postoperative days 1-7. METHODS: Retrospective, observational, multicenter study of 9,258 adult post-cardiotomy patients from 2 Dutch tertiary centers (2015-2024). SCAI SHOCK stage was determined daily during postoperative days 1-7. Endpoint was all-cause in-hospital mortality. Discrimination was performed with area under the curve determination, calibration, and survival analyses. RESULTS: On postoperative day 1, 38% of all post-cardiotomy patients were classified as in shock (stage C-E), and by postoperative day 3 91% of all patients were reclassified as not in shock anymore (stage A-B). In-hospital mortality increased progressively with both higher shock stages and prolonged shock duration. SCAI SHOCK classification showed a strong discrimination for in-hospital mortality between postoperative days 1 and 7 with area under the curve ranging 0.82-0.85. Calibration of the SCAI SHOCK classification improved daily. CONCLUSIONS: Serial SCAI SHOCK classification demonstrated consistent good accuracy and enhanced discrimination over time to predict in-hospital mortality in PCS. In-hospital mortality increased progressively with both higher shock stages and prolonged shock duration. Serial SCAI SHOCK assessment provides additional prognostic value over only initial postoperative staging.