Mizuo Nameki

Intimal hyperplasia regression from 6 to 12 months after stenting

death in hibernating human myocardium. J Am Coll Cardiol 1996;27:1577–1585. 11. Shivalkar B, Maes A, Borgers M, Ausma J, Scheys I, Nuyts J, Mortelmans L, Flameng W. Only hibernating myocardium invariably shows early recovery after coronary revascularization. Circulation 1996;94:308–315. 12. Elsasser A, Schlepper M, Kl‘vekorn WP, Cai W, Zimmermann R, Muller KD, Strasser R, Kostin S, Gagel C, Munkel B, Schaper W, Schaper J. Hibernating myocardium: an incomplete adaptation to ischemia. Circulation 1997;96:2920– 2931. 13. Dakik HA, Howell JF, Lawrie GM, Espada R, Weilbaecher DG, He Z-X, Mahmarian JJ, Verani M. Assessment of myocardial viability with 99mTCsectamibi tomography before coronary bypass graft surgery: correlation with histopathology and postoperative improvement in cardiac function. Circulation 1997;96:2892–2898. 14. Maes A, Borgers M, Flameng W, Nuyts JL, Werf F, Ausma JJ, Serseant P, Mortelmans LA. Assessment of myocardial viability in chronic coronary artery disease using technetium-99 sestamibi SPECT; correlation with histologic and positron emission tomographic studies and functional follow-up. J Am Coll Cardiol 1997;29:62–68. 15. Schwarz ER, Schoendube FA, Kostin S, Schmiedtke N, Schulz G, Buell U, Messmer BJ, Morrison J, Hanrath P, Dahl J. Prolonged myocardial hibernation exacerbates cardiomyocyte degeneration and impairs recovery of function after revascularization. J Am Coll Cardiol 1998;31:1018–1026. 16. Nagueh SF, Mikati I, Weilbaecher D, Reardon MJ, Al-Zaghrini GJ, Cacela D, He Z-X, Letsou G, Noon G, Zoghbi WA. Relation of the contractile reserve of hibernating myocardium to myocardial structure in humans. Circulation 1999; 100:490–496. 17. Shirani J, Lee J, Quigg RJ, Pick R, Bacharach SL, Dilsizian V. Relation of thallium uptake to morphologic features of chronic ischemic heart disease: evidence for myocardial remodeling in non-infarct myocardium. J Am Coll Cardiol 2001;38:84–90. 18. Shirani J, Pick R, Roberts WC, Maron BJ. Morphology and significance of the left ventricular collagen network in young patients with hypertrophic cardiomyopathy and sudden cardiac death. J Am Coll Cardiol 2000;35:36–44. 19. Dilsizian V, Rocco TP, Freedman NM, Leon MB, Bonow RO. Enhanced detection of ischemic but viable myocardium by the reinjection of thallium after stress-redistribution imaging. N Engl J Med 1990;323:141–146. 20. Dilsizan V, Freedman NMT, Bacharach SL, Perrone-Filardi P, Bonow RO. Regional thallium uptake in irreversible defects; Magnitude of change in thallium activity after reinjection distinguishes viable from nonviable myocardium. Circulation 1992;85:627–634.

Difference in security of stent jail between Palmaz-Schatz, NIR, and Multi-Link stents: the effect of balloon inflation through stent struts.

After placing a stent in the main vessel of a bifurcation lesion, it is often necessary to perform further balloon inflation or stent placement through the stent struts in order to treat a lesion of the secondary vessel or side branch. This balloon inflation with dilatation through the cells of the stent in the main vessel results in stent strut disfigurement. This disfigurement causes various degrees of stenosis within the main vessel secondary to stent strut deformity. The degree of strut deformity, and therefore stenosis, may vary significantly depending on stent design and structure. A model of a bifurcation lesion with an angle of 45° was created from acrylic resin. The diameters of the main vessel and the secondary vessel were both 3.5 mm. Deployment of the Palmaz‐Schatz stent (PS, n = 5), NIR stent (n = 5), or Multi‐Link stent (n = 5) was performed in the main vessel with a 3.5‐mm balloon catheter inflated to 6 atm. A second 3.5‐mm balloon catheter was then inflated to 6 atm through the stent struts of the main vessel and into the ostium of the secondary vessel. The minimal lumen diameter (MLD) and cross‐sectional area (CSA) at the ostium of the side branch and the stenosis within the main vessel were then measured, taking into account the stent deformity that occurred. Kissing balloon dilatation with two 3.5‐mm balloon catheters was then performed and the stenosis secondary to stent deformity in the main vessel was remeasured. The MLD of the Multi‐Link stent at the side‐branch ostium was greater compared with those of the Palmaz‐Schatz stent or the NIR stent (2.4 ± 0.1, 1.6 ± 0.1, 1.7 ± 0.1 mm, P < 0.01) and CSA (4.9 ± 0.5, 2.7 ± 0.3, 2.5 ± 0.3 mm2, P < 0.01). Balloon inflation through the stent struts caused stent deformity that resulted in some degree of stenosis within the stent of the main vessel in all three stent types. Kissing balloon inflation reduced, but never eliminated, this stenosis. The percent stenosis in the main vessel secondary to stent deformity (PS 34% ± 9%, NIR 25% ± 8%, Multi‐Link 34% ± 7%, NS) and residual stenosis postkissing balloon inflation (PS 12% ± 1%, NIR 10% ± 3%, Multi‐Link 14% ± 3%, NS) were not significantly different among these three stents. At the side‐branch ostium, the MLD and CSA were significantly greater for the Multi‐Link stent compared with those of the Palmaz‐Schatz or NIR stent. Balloon inflation through the stent struts caused stent deformity that resulted in stenosis within the stent in the main vessel. Kissing balloon inflation reduced this stenosis, but some residual stenosis always remained. The stenoses within the main vessel did not differ among the three stent types. Cathet. Cardiovasc. Intervent. 48:230–234, 1999.

Large pseudoaneurysm after left main trunk stenting sealed by polytetrafluorethylene-covered stent

Left main trunk (LMT) aneurysm is very rare and the management remains uncertain. We describe a patient who developed a pseudoaneurysm from coronary perforation during stent implantation in LMT and was then treated with polytetrafluorethylene (PTFE)‐covered stent graft. PTFE‐covered stent is considered to be a valid strategy for LMT aneurysms. Catheter Cardiovasc Interv 2003;60:233–235.

Subacute mechanical stenosis due to twisted saphenous vein graft identified by intravascular ultrasound

Early saphenous vein graft (SVG) failure is associated with worse long-term outcomes after coronary artery bypass graft surgery [1]. The present intravascular ultrasound (IVUS) images described subacute mechanical stenosis due to the twisted SVG. A 62-year-old man underwent coronary artery bypass graft surgery using SVG with the automatic proximal anastomotic device. SVG flow was satisfactorily maintained and not indicated significant stenosis at the end of surgery. Two weeks later, he was referred for graft angiography. After the administration of nitroglycerin, graft angiography described a new and severe stenosis in the ostial segment of SVG to left circumflex artery (Fig. 1a). Percutaneous coronary intervention for the ostial segment of SVG was decided. IVUS was performed before predilatation (Fig. 1b–d). IVUS showed the stenotic lumen area and the distortion of external elastic membrane area overlapped in layers like tree-ring. However, thrombuswas not seen.After predilatation of the culprit lesion, the distortion was reproduced. Therefore, the ostium of SVG was treated by implantation a 3.5 9 18 mm everolimus-eluting stent (Fig. 1e). SVG flow was successfully improved. IVUS performed after stent implantation showed no stent malapposition (Fig. 1f–h). Follow-up graft angiography at 6 months after stent implantation revealed no in-stent restenosis. IVUS analysis of early SVG failure previously showed significant reference segment plaque burden and diffuse SVG disease without positive remodeling [2]. However, the present images indicated subacute mechanical stenosis due to the twisted SVG. This phenomenon might be related to the automatic anastomotic device. IVUS was useful to evaluate subacute SVG failure.