Side-branch occlusion with directional coronary atherectomy: incidence and risk factors

Side-branch occlusion is a recognized complication of directional coronary atherectomy (DCA). To evaluate the incidence, risk factors, and clinical outcome of side-branch compromise, we analyzed our first 100 consecutive atherectomies of native coronary arteries. Seventy-eight patients had 122 side branches at risk, 21 (17%) of which demonstrated compromised flow after DCA. Origin of the side branch from the culprit atheroma and preexisting side-branch ostial stenosis were highly predictive of this complication in 20 of 55 (p < 0.05) and 14 of 31 (p < 0.05) lesions, respectively. There was one non-Q-wave myocardial infarction, no emergency surgeries, and no deaths. In conclusion, side-branch loss after DCA occurs with a frequency similar to balloon angioplasty and was well tolerated in our patient population. Side branches that originate directly from culprit lesions or that have significant ostial narrowing have a higher incidence of this complication.