Prepared by: Dr. Aysu Oktay

Study Title: DANAMI-3-PRIMULTI: Comparison of complete revascularisation versus infarct-related artery (IRA) only treatment in patients with STEMI and multivessel disease.

Published in: The 10-year results of the DANAMI-3-PRIMULTI study were presented by Thomas Engstrøm at the EuroPCR 2025 congress and simultaneously published in JACC.

Introduction

In patients with ST-segment elevation myocardial infarction (STEMI), the prevalence of multivessel coronary artery disease is approximately 40–50%. Historically, the standard approach during acute MI treatment was to stent only the infarct-related artery (IRA), whereas stenting of non-IRA lesions during the same session or early phase remained controversial. Over the past decade, several randomized trials (e.g., PRAMI, CvLPRIT, DANAMI-3-PRIMULTI, Compare-Acute, COMPLETE) have shown that complete revascularisation either during or shortly after primary percutaneous coronary intervention (PCI) is associated with fewer cardiovascular events than treating only the culprit lesion. However, most of these studies had an average follow-up duration of ~2 years, providing limited insight into long-term outcomes. The DANAMI-3-PRIMULTI trial aimed to assess these long-term effects over a 10-year period.

Aim

The DANAMI-3-PRIMULTI trial was designed to compare infarct-related artery (IRA) only revascularisation with fractional flow reserve (FFR)-guided complete revascularisation in STEMI patients with multivessel disease. The primary aim was to evaluate the 10-year clinical outcomes of both strategies.

Methods

The study included 627 STEMI patients who underwent primary PCI and had multivessel disease. Patients were randomised into two groups: one receiving IRA-only treatment and the other undergoing FFR-guided complete revascularisation. In the complete revascularisation group, non-IRA lesions were evaluated using the FFR ≤0.80 threshold and stented if deemed haemodynamically significant.

Endpoints

The primary endpoint was a composite of all-cause mortality, myocardial infarction, and any repeat revascularisation. Secondary endpoints analysed each of these components individually.

10-Year Results

The primary endpoint occurred in 45% of the complete revascularisation group and 54% of the IRA-only group (HR 0.76; p=0.014). This corresponds to a relative 24% reduction in the long-term risk of major adverse cardiac events. There were no statistically significant differences in all-cause mortality or myocardial infarction between the two groups. However, the need for repeat revascularisation was significantly lower in the complete revascularisation group (38% reduction). This improvement in the primary outcome was largely driven by the reduction in repeat revascularisation procedures. Over 10 years, the mean cumulative number of cardiovascular events per person was significantly lower in the complete revascularisation group, with a 13% absolute risk reduction compared to the IRA-only group (95% CI: –1% to 28%).

Subgroup Analyses

Subgroup analyses showed that patients younger than 65 and those with three-vessel disease derived the greatest relative benefit from complete revascularisation. These subgroups exhibited greater reductions in both the need for revascularisation and the overall event burden.

Clinical Comment

The 10-year results from DANAMI-3-PRIMULTI demonstrate that FFR-guided complete revascularisation significantly reduces long-term major cardiac events compared to IRA-only treatment. This effect is primarily due to fewer revascularisation procedures. The strategy is both safe and effective. These findings suggest that reducing the need for future interventions may enhance patients' long-term quality of life. The principal benefit of complete revascularisation lies not in preventing recurrent MI, but rather in reducing future ischemia-driven angina episodes and associated elective or emergency revascularisations. Moreover, the study confirms that FFR-guided deferral of stenting for non-significant lesions does not pose long-term harm and can help avoid unnecessary stent placement.

Conclusion

In conclusion, the 10-year data from DANAMI-3-PRIMULTI indicate that treating only the culprit lesion may be insufficient in STEMI patients with multivessel disease. Complete revascularisation, when applied to appropriate patients, appears to be a more effective long-term strategy.