Predictors of ostial side branch damage during provisional stenting of coronary bifurcation lesions not involving the side branch origin: an ultrasonographic study

AIMS: To analyse the ultrasound anatomy of bifurcation lesions {1,1,0},{0,1,0} and {1,0,0} of the Medina classification in order to identify predictors of angiographic side branch (SB) damage after main branch (MB) stenting. METHODS AND RESULTS: One hundred and ten patients with Medina classification bifurcation lesions of {1,1,0},{0,1,0} and {1,0,0} were recruited. An intravascular ultrasound study (IVUS) was performed on the MB before treatment, after stent implantation and after SB intervention. A quantitative analysis was conducted in combination with a qualitative study of the carina morphology and plaque distribution. Ostial SB damage (an increase of the percentage of ostial stenosis by QCA ≥30%) was observed in 51 lesions (48%) after MB stenting. The baseline IVUS identified a carina with a spiky morphology ("eyebrow" sign) in 51 bifurcations. In 41 out of 51 bifurcations with this sign, ostial SB damage was induced after stenting the MB due to carina shift (p<0.01). Narrower angiographic angles were associated with the presence of the "eyebrow" sign (62º±23º vs. 76º±24º, p<0.05). Plaque located at the carina was associated with a lower rate of ostial SB damage (29%) when compared with those lesions with no plaque exhibiting at the carina (51%), p<0.05. CONCLUSIONS: The "eyebrow" sign is a powerful predictor of ostial SB damage after stent implantation in the MB in bifurcation coronary lesions without plaque involving the SB.