Background: Among patients with acute myocardial infarction (AMI) referred for primary percutaneous coronary intervention (PCI), those with multivessel disease have worse clinical outcomes. This study sought to elucidate the impact of a chronic occlusion in a noninfarct vessel among patients with multivessel disease undergoing PCI for AMI.
Methods and results: We studied 630 patients with AMI treated with PCI within 12 hours of symptom onset. Three groups of patients were defined: Group 1 (single-vessel disease; n = 345); Group 2 (multivessel disease with no chronic coronary occlusion in another vessel; n = 201); and Group 3 (chronic coronary occlusion in another vessel; n = 84). The probability of being free from events was lower in patients with multivessel disease than in Group 1 (84 +/- 2% vs. 92 +/- 1% at 30 days; 71 +/- 3% vs. 81 +/- 3% at 2 years; Log-Rank: p = 0.001; Breslow: p < 0.001 ), and in Group 3 than in Group 2 (76 +/- 5% vs. 87 +/- 2% at 30 days; 63 +/- 6% vs.75 +/- 4% at 2 years; Log-Rank: p = 0.014; Breslow: p = 0.008 ). Freedom from cardiac death was lower in patients with multivessel disease than in Group 1 (88 +/- 2% vs. 94 +/- 1% at 30 days; 84 +/- 2% vs. 91 +/- 2% at 2 years; Log-Rank: p = 0.003; Breslow: p = 0.002), and in Group 3 than in Group 2 (82 +/- 4% vs. 90 +/- 2% at 30 days; 77 +/- 5% vs. 88 +/- 3% at 2 years; Log-Rank and Breslow: p = 0.020). Among patients with multivessel disease, the presence of cardiogenic shock, left main disease and anterior location, but not the presence of a chronic occlusion in another vessel, were independent predictors of mortality.
Conclusion: Among patients with AMI and multivessel disease, those with a chronic occlusion in a noninfarct-related vessel constitute a subgroup with very poor clinical outcomes.