Tehran University Medical Journal (Jul 2007)
Predictors of Side Branch Compromise and related early complications after percutaneous coronary intervention
Abstract
Background: Percutaneous Coronary Intervention (PCI) for bifurcated lesions is associated with a low rate of success and high rate of complications compared to such treatment of lesions of most other morphologies. Symptoms occurring at the time of procedure caused by PCI may require additional angiography with or without stenting through stent struts, which subsequently increases risks of restenosis and stent thrombosis. The purpose of this study was to evaluate the incidence of major side branch (>1mm) complications during PCI and their clinical, angiographic, and interventional predictors. Methods: Of 104 consecutive patients, we evaluated 50 lesions with ostial stenosis (group 1) and 54 lesions without ostial stenosis (group 2) as a control group. Age, sex, major coronary artery disease risk factors, and left ventricular ejection fraction (LVEF), were compared between groups. Morphology, location, type of lesion, length of lesion, main and side branch diameters, interventional approach, and clinical and interventional outcomes were the main variables studied during this trial. Results: Side Branch Compromise (SBC) occurred in 41 (39.4%) of the total number of cases: 52% in group 1 and 27.8% in group 2 (p=0.01). More than 80% of SBC occurred in main branches with stenosis (p=0.02). SBC did not correlate with clinical characteristics, bifurcation location, LVEF, or stent number. Chest pain was reported in 18% of the cases during or after PCI. Three non Q wave myocardial infarctions (MI) occurred after SBC, each with >2 mm branch diameters (p=0.02). SBC was not associated with adverse clinical outcomes. Conclusion: The risk of MI after losing the side branch of a bifurcation lesion is not usually as high as it is after losing the main branch. Furthermore, it may not be a serious problem as one of the problems of the bifurcation lesion is the high rate of post procedural non Q wave MI associated with SBC. These findings demonstrate that side branch ostial stenosis >50%, and main branch stenosis >80% were important predictors of SBC. Protection of side branches >2mm is highly recommended during coronary intervention.