Differences in Care and Outcomes in Cardiogenic Shock in Cardiac Intensive Care Units in the United States and Canada: CCCTN Registry Insights

Background

Mortality in cardiogenic shock (CS) remains high. Significant interhospital heterogeneity in critical care therapies has been described, which reflects the lack of high-quality evidence to guide optimal treatment. We aimed to describe differences in practices and clinical outcomes among patients with CS in the United States and Canada.

Methods

The Critical Care Cardiology Trials Network (CCCTN) is a research network of tertiary cardiac intensive care units (CICUs). Data collection spanned from 2017 to 2022. The analysis included 34 American and 8 Canadian sites. The outcomes of interest included baseline clinical differences, use of critical care monitoring and therapies, and all-cause in-hospital mortality between patients with CS in the United States and Canada admitted to CICUs.

Results

Among 23,299 admissions, 19% had CS (n = 4336, 88% United States vs 12% Canada). The proportion of patient who received invasive hemodynamics (United States: 80.8% vs Canada: 74.8%, P = 0.0015), vasoactive medications (United States: 88.9% vs Canada: 82.1%, P < 0.0001), temporary mechanical circulatory support (tMCS) (United States: 39.4% vs Canada: 23.1%, P < 0.0001) were more frequent in US centres. Intra-aortic balloon pump was the most common tMCS device in both countries. After multivariable adjustment, in-hospital mortality was higher in Canada vs United States (37.1% vs 29.4%, odds ratio [OR]: 1.47; 95% confidence interval [CI], 1.18-1.83).

Conclusions

In a contemporary registry, management of CS was heterogenous between the United States and Canada, with higher use of invasive monitoring and MCS in the US. Although adjusted mortality was lower in the United States, the effects of these treatments cannot be reliably determined without randomized trial data.