Carina Shift Versus Plaque Shift for Aggravation of Side Branch Ostial Stenosis in Bifurcation Lesions

Impact of plaque type and side branch geometry on side branch compromise after provisional stent implantation: a simulation study

“…The ellipticity ranges between 0 and 1, 0 being a perfect circle, while an increase of the value indicates that the lumen is becoming more oval. SB ostium compromise was also investigated by volumetric analysis 8 . The lumen volume of an SB segment of 5 mm from the SB ostium was computed.…”

“…Two different distal angles in the physiological range, namely 45° and 70°, were used, while the proximal angle was set to 150°1 8,19 . The model was also bent on a sphere with a radius of 56.3 mm 20 to account for the curvature of the heart.…”

“…A potential complication of this procedure is the aggravation of side branch (SB) ostial stenosis after stent implantation in the main branch (MB) 1,2 and the associated increased risk of periprocedural myocardial infarction [3][4][5] . SB ostium compromise after PSB has been attributed to plaque shift from the MB into the SB 6 or to the shift of the carina into the SB [7][8][9][10] . Several potential predictors of SB ostium occlusion after MB stenting, including SB lumen diameter 11 , distal bifurcation angle 5,9,12 , MB calcified plaque 13 , SB plaque length 4 and thickness 11…”

Is it possible to further improve clinical results with coronary bifurcation stenting, or what is more important — the technique or the stent?

“…In a recent study Idris et al [39] explored how the definition of PMI could affect the prognosis after PCI from 742 patients; 492 (66%) had normal troponin T (TnT) levels and 250 (34%) had elevated, but stable or falling, TnT levels. PMI, using the 2007 [40] and the 2012 [41] universal definition, occurred in 172 (23.2%) and in 99 (13.3%) patients, respectively, whereas only 19 (2.6%) met the Society for Cardiovascular Angiography and Interventions (SCAI) PMI definition (p < 0.0001). Among patients with PMI using the 2012 definition, SB occlusion occurred in 53 (54%) patients; SB diameters were ≤ 1 mm in 48 patients, > 1 mm to < 2 mm in three patients, and ≥ 2 mm in two patients and was the most common angiographic finding for PMI.…”

“…We and others [28,40,42] have demonstrated that the most important mechanism of SB stenosis occurrence is displacement of the bifurcation carina tip from stent struts in the direction of the SB ostium. The carina displacement is the leading mechanism of SB closure, but additional plaque shifting from the main vessel or plaque redistribution of SB ostium per se is necessary to close the vessel completely [27,40,42]. However, even without closure, the branch could be stenosed enough to cause ischaemia.…”