Objective: To evaluate the safety and efficacy of surgical treatment approach vs. conservative approach in patients with ambiguous lesions in the left main coronary artery (LMCA), based on intracoronary ultrasound (ICUS) findings.
Methods: Sixty-six consecutive patients with angiographically ambiguous lesions were included and submitted to ICUS assessment. They were divided in two groups, according to the ICUS findings. Group I was maintained under clinical treatment [minimal lumen area (MLA) > 6.0 mm(2) and/or minimal lumen diameter (MLD) > 2.5 mm] and Group II was submitted to revascularization (MLA < 6.0 mm(2) and/or MLD < 2.5 mm). The occurrence of major cardiac events (death, acute myocardial infarction and/or revascularization of the target lesion) was assessed during follow-up.
Results: Forty-one (62%) patients were allocated in Group I and 25 (38%) in Group II. Mean follow-up was 42.1 months. The coronary angiography did not differentiate the two groups regarding lesion severity (MLD 1.98 mm in Group I vs. 1.72 mm in Group II; p = 0.75) in opposition to ICUS (MLD 3.41 mm in Group I vs. 2.01 mm in Group II; p < 0.001). There was no death or myocardial infarction in Group I. The survival rate free of major cardiac events was 95% in Group I vs. 87.5% in Group II (p=ns).
Conclusion: Treatment decision-making of patients with ambiguous lesions in the LMCA guided by ICUS findings showed to be safe and effective.