Primary Percutaneous Coronary Intervention Guided by High-Definition Intravascular Ultrasound (The SPECTRUM Study).

BACKGROUND: Limited data are available on the use of intravascular ultrasound (IVUS) in patients presenting with ST-segment elevation myocardial infarction (STEMI). AIMS: This study aimed to assess the impact of IVUS-guided primary percutaneous coronary intervention (PCI). METHODS: SPECTRUM (NCT05007535) was a prospective, single-center, observational cohort study. STEMI patients presenting within 12 h after symptom onset with stable hemodynamics and undergoing primary PCI of a native culprit lesion (angiographic reference diameter ≥ 2.25 mm) were eligible. Pre-intervention, post-intervention and post-optimization (if applicable) HD-IVUS pullbacks were obtained per protocol. The primary endpoint was target vessel failure (TVF) at 12 months, a composite of cardiovascular death, target vessel myocardial infarction, and target vessel revascularization. The secondary endpoint was presence of IVUS-guided optimization. RESULTS: A total of 200 STEMI patients were included. Mean age was 62.1 (±12.5) years, 69% were male, 11.0% had diabetes and the left anterior descending was the culprit vessel in 44.0%. IVUS-guided optimization was performed in 41.1%. Optimal PCI, based on predefined IVUS criteria, increased from 52.1% post intervention to 65.5% post optimization (p < 0.001). A stent-edge plaque burden > 50% was the main reason for not achieving optimal PCI results after IVUS-guided optimization (94.4%). TVF at 12 months occurred in 3.0% (95% CI 1.1%-6.4%). CONCLUSIONS: SPECTRUM is the first dedicated prospective study demonstrating the potential of IVUS to optimize outcomes in a primary PCI setting. IVUS guidance in primary PCI was safe, significantly increased the number of STEMI patients with an optimal PCI result and resulted in low rates of TVF at 12 months.