# Analysis of inter-hospital transfer on clinical outcomes after primary percutaneous coronary intervention for ST-segment elevation myocardial infarction: A secondary analysis of the BRIGHT-4 trial

## TL;DR

This study found that transferring STEMI patients for PCI does not worsen 30-day outcomes, and bivalirudin reduces risks of death and bleeding compared to heparin.

## Contribution

The study provides evidence that inter-hospital transfer does not negatively impact outcomes and that bivalirudin is effective regardless of transfer status.

## Key findings

- Transferred patients had no worse 30-day outcomes compared to directly admitted patients.
- Bivalirudin reduced the risk of death or major bleeding in both transferred and directly admitted patients.
- Timely PCI was more important than the need for transfer in determining outcomes.

## Abstract

Previous studies evaluating the influence of inter-hospital transfer on mortality in ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PCI) reported conflicting results. The multicenter BRIGHT-4 trial demonstrated that bivalirudin plus a post-PCI high-dose infusion (1.75 mg/kg/h) reduced the 30-day primary endpoint of all-cause mortality or Bleeding Academic Research Consortium (BARC) types 3–5 bleeding compared with heparin monotherapy in STEMI patients. This study aimed to assess the impact of inter-hospital transfer on clinical outcomes and the effectiveness of bivalirudin versus heparin in STEMI patients undergoing PCI.

In BRIGHT-4, 2,121 (35.7%) patients were transferred to a tertiary hospital for primary PCI while 3,817 (64.3%) were directly admitted to an interventional facility. The primary outcome was the composite of all-cause death or BARC types 3–5 bleeding occurring within 30 days. The secondary outcomes included stent thrombosis. Adjustments were made for baseline covariates and randomized treatments. Transferred patients had a longer median time from symptom onset to wire crossing the infarct-related artery (6.00 versus 3.93 hrs, P < 0.0001). At 30 days, there were no significant between-group differences in the rates of the primary outcome (4.2% versus 3.4%, adjusted hazard ratio [HR] 0.99, 95% confidence intervals [CI] 0.73, 1.33, P = 0.94) or its components. Bivalirudin with a high-dose post-PCI infusion was associated with consistent reductions of the primary outcome in the transfer (3.5% versus 4.8%, adjusted HR 0.66, 95%CI 0.42, 1.05) and direct admission (2.8% versus 4.1%, adjusted HR 0.62, 95% CI 0.43, 0.89) group compared with heparin monotherapy (Pinteraction = 0.78), as well as individually for stent thrombosis. The main limitations of this study are that it is a post hoc analysis, and the long-term prognostic impact of transfer on STEMI patients requires further investigation.

In this post hoc analysis, 30-day clinical outcomes for STEMI patients transferred for PCI were not significantly worse than direct admission patients. Bivalirudin with a post-PCI high-dose infusion for 2–4 hrs was associated with lower rates of 30-day all-cause mortality, major bleeding and stent thrombosis, consistently observed in transfer and direct admission patients.

BRIGHT-4 trial NCT03822975
http://www.clinicaltrials.gov

Many ST-segment elevation myocardial infarction (STEMI) patients present at non-percutaneous coronary intervention (PCI) capable hospitals and require transfer, a process that may prolong ischemic time and increase mortality.

The large-scale BRIGHT-4 trial found that using bivalirudin instead of heparin, followed by a 2–4-hr post-PCI high-dose infusion, significantly lowered the risk of death or major bleeding within 30 days in patients with STEMI undergoing primary PCI.

Current clinical practice lacks evidence on outcomes and optimal anticoagulation for transferred STEMI patients.

We conducted a post hoc analysis of the BRIGHT-4 trial, focusing on 5938 patients with STEMI undergoing primary PCI, all of whom had clear records of how they arrived at PCI-capable hospitals.

Despite a 2-hr delay to reperfusion, patients who had to be transferred for primary PCI did not have worse outcomes after 30 days compared to those who arrived directly at PCI-capable hospitals.

The association between bivalirudin use and lower rates of death or major bleeding appeared to be maintained regardless of the need for inter-hospital transfer.

This study emphasized that speed mattered most - timely PCI treatment was more important than how patients got to the hospital, whether they came directly or were transferred.

When treating STEMI patients with primary PCI, bivalirudin could be a reasonable option no matter how the patient got to the hospital – even if they had to be moved from another facility. The connection between using bivalirudin and better outcomes (fewer deaths, less bleeding) stayed consistent either way.

The generalizability of the present study is limited by not fully balancing the differences between patients who were transferred and those who arrived directly at the hospital, as well as by a relatively short follow-up period. More research is needed to see how inter-hospital transfer affects the long-term prognosis of STEMI patients and to assess the benefits of bivalirudin over time.

In this secondary analysis of the BRIGHT-4 trial, Xioalin Su and colleagues assess whether patients with ST-segment elevation myocardial infarction and who require transfer to a tertiary hospital for percutaneous coronary intervention (PCI) differ in outcomes from patients who are directly admitted for PCI.