Intravenous Nicorandil in Patients With ST-Segment Elevation Myocardial Infarction Undergoing Primary PCI: The CLEAN...

Nicorandil, an adenosine triphosphate-sensitive potassium-channel opener with nitrate-like properties, may reduce reperfusion injury and microvascular obstruction in ST-segment elevation myocardial infarction (STEMI), but large-scale randomized evidence on long-term clinical outcomes is inconclusive.

The CLEAN trial aimed to assess whether adjunctive intravenous nicorandil improves 12-month clinical outcomes in patients with STEMI undergoing primary percutaneous coronary intervention.

In this multicenter, randomized, double-blind, placebo-controlled trial conducted at 49 hospitals in China, patients aged 18 to 80 years with STEMI within 12 hours of symptom onset were randomly assigned (1:1) to receive intravenous nicorandil (6 mg bolus before reperfusion followed by 6 mg/h infusion for 48 h) or matching placebo. Oral nicorandil was prohibited during follow-up. The primary outcome was a composite of cardiovascular death, nonfatal myocardial infarction, target vessel revascularization, or unplanned hospitalization for heart failure within 12 months.

Between January 2021 and December 2023, 1,503 patients were enrolled and randomly assigned to nicorandil (n = 748) or placebo (n = 755). The primary composite outcome occurred in 98 patients (13.1%) in the nicorandil group (113 events over 717.2 person-years) and 99 (13.1%) in the placebo group (136 events over 710.3 person-years), with no significant difference between groups (rate ratio: 0.869; 95% CI: 0.650-1.162; P = 0.3429). Among secondary outcomes, nominal reductions were observed in cardiovascular death (1.9% vs 3.6%; HR: 0.515; 95% CI: 0.269-0.983) and target-vessel revascularization (1.1% vs 3.0%; HR: 0.322; 95% CI: 0.143-0.727), whereas rates of nonfatal myocardial infarction and unplanned hospitalization for heart failure were similar between groups. Adverse events did not differ between groups.

In patients with STEMI undergoing primary percutaneous coronary intervention, adjunctive intravenous nicorandil did not significantly reduce the 12-month primary composite outcome. These findings do not support routine use of intravenous nicorandil in unselected patients with STEMI. (Clinical Efficacy and sAfety of Intravenous Nicorandil; NCT04665648).