The impact of sex and its interaction with temporary mechanical circulatory support in cardiogenic shock patients

BACKGROUND: Temporary mechanical circulatory support (tMCS) is increasingly used in managing cardiogenic shock, yet women remain underrepresented in studies evaluating its role. This analysis aims to clarify sex-specific in-hospital outcomes among cardiogenic shock patients treated with and without tMCS. METHODS: We analyzed consecutive cardiogenic shock patients enrolled from January 2020 to November 2023 in the multicenter Altshock-2 Registry. The primary outcome was in-hospital mortality. RESULTS: Among 692 patients [162 (23%) women, 530 (77%) men, mean age 65 (SD 14) years], cardiogenic shock was due to myocardial infarction in 50.1% and heart failure in 29.1%. Other causes were more common in females vs. males (30.5 vs. 17.8%, P value 0.03). At presentation, women had higher lactate levels [3.4 (1.7-7.3) vs. 2.6 (1.6-5.3) mmol/l, P value 0.03] and more frequent severe right ventricular dysfunction (61.8 vs. 49.6%, P value 0.02). tMCS was used in 445 (64.7%) patients without significant sex differences (P value 0.5). Intra-aortic balloon pump was the most used device (73% women vs. 82% men, P value 0.06), followed by extra corporeal membrane oxygenation (33.7 vs. 29.7%, P value 0.4) and Impella (18.8 vs. 23.5%, P value 0.3). A not-significant higher in-hospital mortality in women emerged in the overall (41.4 vs. 33.2%, P value 0.06) and in the tMCS (41.6 vs. 32%, P value 0.07) groups. At multivariate Cox regression analysis, female sex was associated with higher in-hospital mortality only in the tMCS group (adjusted hazard ratio 1.59; 95% confidence interval 1.05-2.39; P value 0.03). No differences emerged in terms of MCS-related complications (28 vs. 25%, P value 0.6). CONCLUSION: Female sex is associated with a worse in-hospital survival among cardiogenic shock patients treated with tMCS. Future research should ensure adequate female representation to clarify underlying mechanisms.