Variation in practice for out-of-hospital cardiac arrest treated with percutaneous coronary intervention in England and Wales

Objectives We assessed the association between total center volume, operator volume, and out-of-hospital cardiac arrest (OHCA) percutaneous coronary intervention (PCI) volume. Background Variations between OHCA PCI volume, hospital total PCI, and primary PCI volume are not well studied and are unlikely to be clinically justifiable. Methods Patients undergoing PCI for the acute coronary syndrome (ACS) between January 1, 2014, and March 31, 2019, in England and Wales were grouped as OHCA PCI and non-OHCA PCI. Spearman's correlation was used to determine the degree of correlation between each hospital PCI volume and OHCA PCI volume. Results Out of 250,088 PCI procedures undertaken for ACS, 12,016 (4.8%) were performed for OHCA, and 238,072 (95.2%) were non-OHCA PCI procedures. The OHCA PCI group were younger [mean age (SD) 63.2 (12.3) and 65.6 (12.5, p < 0.001)], less likely to be female (20.2% vs. 26.9%, p < 0.001) or Black, Asian, and Minority Ethnicity (11.5% vs. 14.8%, p < 0.001) compared to the non-OHCA PCI group. Although there was a degree of correlation between total PCI and OHCA PCI, there was wide variation for both ACS cohort (Spearman correlation R-2 = 0.50) and total PCI volume (Spearman correlation R-2 = 0.60). Furthermore, the correlation between primary PCI volume and OHCA PCI within centers was weak (R-2 = 0.10). Similarly, wide variations between operator PCI volume and OHCA PCI volume were observed. Conclusion These national data demonstrate wide variation in the practice of OHCA PCI both between centers and individuals. These variations are not expected according to clinical factors and require further investigation.