Objectives To clarify the underlying mechanism for the high
restenosis rate after the coronary angioplasty for the chronic
total occlusion by using the coronary angioscope.Background
Coronary angioplasty for the chronic total occlusion is associated
with higher restenosis rate than for highly stenotic lesion.
However, the difference in the restenosis rate has not been
discussed from the angioscopic observation.Methods and Results The lesion morphology after coronary
intervention were classified into 4 grade (Grade 0 = no intimal flap; Grade 1 = intimal flap without protrusion; Grade 2 = Intimal flap with protrusion not occlusive; Grade 3
= protruding intimal flaps with occlusion of the vessel
lumen). Coronary angioscopic observation was performed in 46
patients with stable angina. Most of the lesion morphology after
angioplasty in 13 patients with chronic total occlusion was grade
3. On the other hand, none of grade 3 was observed in 36 patients
with severe coronary stenosis.Conclusion The various protrusions into the lumen shown by the angioscope might be a
reason for higher restenosis and reocclusion rates compared with those after the angioplasty
for the severe stenotic lesion.