Very late changes in the dilated lesion following coronary balloon angioplasty: a 17 year serial quantitative angiographic study.

AIMS: Limited data are available on the changes that occur at the dilated site many years after coronary balloon angioplasty. The development of bioabsorbable stents may increase the importance of understanding the long term changes that occur in an unscaffolded coronary artery following balloon-mediated injury. METHODS AND RESULTS: This study evaluated, by serial quantitative angiography, the natural history of changes that occurred in the dilated segment between early (mean seven months), late (mean 4.5 years) and very late (mean 17 years) follow-up after balloon angioplasty. Of 127 consecutive patients (174 lesions) with successful coronary angioplasty, 125 underwent early, 84 late and 47 very late angiographic follow-up (75% of eligible survivors). The mean lesion diameter stenosis decreased from 36+/-11% at early to 26+/-15% at late follow-up (p<0.0001), and then increased again to 35+/-25% by very late follow-up (p=0.003). Although stenosis severity at early follow-up angiography predicted lesion regression at late follow-up, there was no significant correlation between late and very late follow-up lesion severity. CONCLUSIONS: After coronary angioplasty, lesion regression at the dilated site from 7 months to 4.5 years is followed by slow lesion progression over the next 12 years.

The "crush" technique for coronary artery bifurcation stenting: insights from micro-computed tomographic imaging of bench deployments.

OBJECTIVES: This study provides insights into "crush" coronary bifurcation stenting through imaging of bench deployments. BACKGROUND: Although the strategy of provisional side-branch stenting is widely accepted for suitable bifurcation lesions, there is no consensus on the best option for elective stenting with 2 stents. The crush technique has the potential to scaffold and apply the drug to the side-branch ostium where restenosis is most common. METHODS: Sequential steps of crush stent deployment and post-dilation were undertaken in silicone phantoms and recorded on cine angiography and microcomputed tomography. We assessed the effect of deployment strategies, post-dilation strategies, and cell size on side-branch ostial area. RESULTS: Side-branch ostial coverage by metal struts was 53% (95% confidence interval [CI]: 46 to 59) after 1-step kissing post-dilation and was reduced by 2-step kissing post-dilation to 33% (95% CI: 28 to 37; p < 0.0001). Although the residual stenosis after the classical crush strategy was 47% (95% CI: 39 to 53), it was 36% (95% CI: 31 to 40; p = 0.002) after mini-crush deployment. Stents with larger cell size (>3.5 mm diameter) had a residual stenosis of 37% (95% CI: 32 to 42) after crush deployment that was less than the residual stenosis for stents with smaller cell size (52%; 95% CI: 44 to 60; p < 0.0001). CONCLUSIONS: Side-branch ostial stenosis after crush stenting was minimized by mini-crush deployment, 2-step kissing post-dilation, and the use of stents with larger cell size. It is unknown if optimizing stent deployment at bifurcation lesions will reduce clinical stent thrombosis and restenosis.