Changing the coronary bifurcation angles after stenting procedures: the relevance to the technique and unfavorable outcome (Three-dimensional analysis).

Aim: Percutaneous transluminal balloon co-ronary angioplasty (PTCA) of coronary bifurcations is associated with a low success rate, higher rate of complications and need for revascularazation. We sought to analyze: 1) the change in 3D measurement of angles following stenting of coronary bifurcations; and 2) if changes in these angles might predict unfavourable outcomes.

Methods: Coronary angiograms of 102 patients with bifurcation lesions were analyzed with 3D software (CardiOp-B) before and after stenting. The change in angle between the proximal main artery and side branch (BA), and between the distal main artery and side branch (BS) were measured. A change of ≥ 5° after stenting was considered significant. The results were compared with clinical follow-up.

Results: Bifurcation lesions included 66 left anterior descending/first diagonal (LAD/D1) lesions, 15 left main stem (LMS) lesions, 19 atrioventricular circumflex/obtuse marginal (AVCx/OM) lesions, and 2 coronary artery (RCA) crux lesions. BA and BS measured 138.3° ± 17.2° and 64.3° ± 20.6° respectively. Stent deployment altered BA and BS significantly in 80-90% of cases. Furthermore, BS correlated positively with the magnitude of change in BS after stenting. BA was unaffected by the complexity of the stenting procedure, whereas BS increased significantly in complex versus simple stenting strategies (P<0.05). Procedure related complications occurred in 15.6% of patients. The incidence of in-hospital complications was lower when BA was increased (P<0.05). The one year incidence of the composite of in-hospital complications and late complications was also significantly lower when BA was increased by ≥ 5° (P=0.027). A decrease of BA was associated with 80% more complications compared to cases where BA was increased. No correlation was found between the change of BS and procedural or late complications.

Conclusion: 3D measurements of coronary bifurcation angles prior to stenting can predict changes in bifurcation geometry after stenting. A decrease in BA after stenting is a strong predictor for less favourable outcomes of coronary bifurcation stenting procedures.