Impact of annual volume of cases and intensive cardiac care unit availability on mortality of patients with acute myocardial infarction-related cardiogenic shock treated at revascularization capable centres.

Abstract

Cardiogenic shock (CS) is associated with high mortality. The purpose of this study was to assess the impact of hospital structure-related variables on mortality in patients with CS treated at percutaneous and surgical revascularization capable centres (psRCC) from a large nationwide registry. Retrospective observational study including consecutive patients with main or secondary diagnosis of CS and ST elevation myocardial infarction (STEMI). Patients discharged from Spanish National Healthcare System psRCC were included (2016-20). The association between the volume of CS cases attended by each centre, availability of intensive cardiac care unit (ICCU) and heart transplantation (HT) programmes, and in-hospital mortality was assessed by multilevel logistic regression models. The study population consisted of 3074 CS-STEMI episodes, of whom 1759 (57.2%) occurred in 26 centres with ICCU. A total of 17/44 hospitals (38.6%) were high-volume centres, and 19/44 (43%) centres had HT programmes availability. Treatment at HT centres was not associated with a lower mortality (P = 0.121). Both high volume of cases and ICCU showed a trend to an association with lower mortality in the adjusted model [odds ratio (OR): 0.87 and 0.88, respectively]. The interaction between both variables was significantly protective (OR 0.72; P = 0.024). After propensity score matching, mortality was lower in high-volume hospitals with ICCU (OR 0.79; P = 0.007). Most CS-STEMI patients were attended at psRCC with high volume of cases and ICCU available. The combination of high volume and ICCU availability showed the lowest mortality. These data should be taken into account when designing regional networks for CS management.