血管内超声对分叉病变支架置入术后分支闭塞的预测

Intravascular ultrasound predictors of side branch occlusion in bifurcation lesion after percutaneous coronary intervention

目的:应用血管内超声(IVUS)分析分支闭塞的预测因素。方法:行冠状动脉介入治疗(PCI)的分叉病变52处,定量分析分叉近端(分支入口平面)和分叉远端(分叉嵴平面)斑块面积、斑块负荷、偏心指数、斑块分布弧度。采用逐步回归法分析PCI术后分支斑块负荷的相关因素。对术前分支斑块负荷>50%(n=15)和<50%(n=37)这2种情况进行术后结果比较。结果:定量分析分叉近端和远端斑块负荷差异无统计学意义[(52.80±13.21)%∶(52.81±12.20)%,P>0.05],分叉近端斑块偏心指数明显低于分叉远端[(1.86±0.64)∶(9.52±2.78,P<0.01],分叉近端斑块弧度明显大于分叉远端[(357.15±12.02)°∶(233.33±45.91)°,P<0.01]。分叉远端斑块与分支的角度为(143.2±33.60)°。逐步回归分析显示,术后分支斑块负荷与术前分支斑块负荷、分叉近端斑块负荷正相关,与分叉角度、分支/主支直径负相关。术后分支斑块负荷在术前分支斑块负荷>50%者明显大于<50%者[(89.20±5.66)%∶(42.60±18.12)%,P<0.01]。结论:血管分叉改变了斑块的分布模式,分叉近端斑块向心性分布,而分叉远端斑块偏心性分布。分叉远端斑块主要分布在分叉嵴的对侧壁。术前分支斑块负荷大、分叉近端斑块负荷大,分叉角度小、分支/主支直径小,分叉病变PCI术后分支闭塞的可能性大。分支开口斑块负荷>50%较<50%术后闭塞的危险性更大。

Objective:Side branch compromise after percutaneous coronary intervention(PCI)has been associated with acute complications and poor long-term outcomes in bifurcation lesions.Coronary angiography cannot predict which branch likely to be jailed.It suggest that intravascular ultrasound can help to identify side branch likely to occlude after PCI.Method:Fifty-two coronary bifurcation lesions in 45 patients were enrolled in our study.Plaque area,plaque burden,eccentric index and plaque arc in side branch entrance cross-sections and bifurcation crista cross-sections are measurea.We surveyed influential factors correlated with post-procedural plaque burden of side branch with stepwise regression analysis.The outcome of PCI was compared between branches with 50% or more plaque burden at their origin and those with less than 50% plaque burden.Result:Quantitative analysis showed that EI were smaller in proximal segment than distal segment(1.86±0.648)∶(9.52±2.7),P=0.000,plaque arc were larger in proximal segment than distal segment(357.15±12.02)∶(233.33±45.91)°,P=0.000,but plaque burden were similar in both segments(52.80±13.21)%∶(52.81±12.20)%,P=0.997.We identified post-procedural plaque burden of side branch was correlated with pre-procedural plaque burden of side branch and proximal segment plaque burden positively,and was correlated with side-branch take-off angle and diameter ratio(side branch diameter divide main vessel diameter)negatively.Post-procedural plaque burden was larger in branches with 50% or more plaque burden than those with less than 50% plaque burden.Conclusion:Characteristic patterns of plaque distribution was transformed by coronary bifurcation.Plaque is concentric in proximal segment but eccentric in distal segment.Side branch with large pre-procedural plaque burden,large plaque burden in proximal segment of bifurcation,small side-branch take-off angle,small diameter ratio are in high risk of side branch occlusion after PCI.