Purpose: To evaluate the incidence and clinical presentation of the occlusion of such secondary branches in patients with single vessel coronary artery disease in the left anterior descending artery, who underwent a first elective and successful PTCA.
Material and methods: Two hundred and thirteen side branches of 121 patients considered to be at risk. They were divided into group I (GI-85 side branches, 39.9%), if they originated from the atherosclerotic site; and group II (GII-120 side branches, 61.5%), if their origin would be involved during the balloon inflation. In the GI there were 54 septal branches and 31 diagonal branches, and 36& had angiographic evidence of ostium disease. GII was constituted by 77 septal and 51 diagonal branches, and 7.8% of them had evidence of ostium disease.
Results: Seven side branches (3.3%) at risk occluded, 4 from GI (4.7%) and 3 (2.3%) from GII. As for the clinical presentation, 57% of them had angina, where as 28.6% showed minor abnormalities in the ECG. No patient elevated its serum CK-MB, and silent occlusion occurred in 43% of them.
Conclusion: Occlusion of side branches is a low incidence phenomenon, which happens more often in septal branches with ostium disease that originates from the atherosclerotic site; that about half of the patient had silent occlusion (43%) or mild ischemic manifestations.