Hideo Shinji

Incidence and predictors of the late catch-up phenomenon after drug-eluting stent implantation

BACKGROUND Although clinical restenosis within 1 year after percutaneous coronary intervention has been remarkably reduced with the advent of drug-eluting stents (DES), the late catch-up (LCU) phenomenon remains an issue despite medical advances. The aim of this study was to investigate the incidence and predictive factors of the LCU phenomenon in an unselected population treated with first-generation DES. METHODS A total of 923 patients treated with DES between June 2004 and August 2008 were analyzed. The LCU phenomenon was defined as secondary revascularization 1 year after index stenting. Retreatment for very late stent thrombosis was considered as part of the LCU phenomenon. RESULTS Incidence of the LCU phenomenon was seen in 33 patients (3.6%). Very late stent thrombosis was observed in 5 patients (0.6%) and very late in-stent restenosis was observed in 28 patients (3.0%). At the 12-month landmark analysis, the cumulative rate of cardiac death was significantly higher in patients with the LCU phenomenon than in those without any target lesion revascularization (9.0% vs. 0.9%, p<0.001). In the multivariate analysis, hemodialysis [odds ratio (OR) 6.07, p=0.003], number of stents (OR 1.58, p=0.02), and coronary bifurcation lesions (OR 2.06, p=0.048) were identified as independent predictors of the LCU phenomenon. CONCLUSION The LCU phenomenon is associated with serious consequences and adverse events and remains an important issue in modern practice, despite medical advances. DES should be deployed with a minimum number of stents, and special consideration must be given to patients on hemodialysis and those with coronary bifurcation lesions.

Stent deformation: an experimental study of coronary ostial stenting☆

OBJECTIVES To investigate stent deformation by torsional stress after implantation at the ostium of a model coronary artery. BACKGROUND Little is known about coronary stent deformation, especially the association between stent design and deformation at the coronary ostium. Recent reports have suggested that mechanical factors are important for stent restenosis. METHODS A coronary ostium model was constructed and three different stents (Express(2), Cypher, and Tsunami, n=5 each) were implanted at the aorto-ostial junction. Differences of stent deformation were assessed after exposure to torsional stress. Intravascular ultrasound was used to measure the luminal area along each stent. Then the extent and pattern of plastic deformation were compared between the three stent types. RESULTS The Express(2) stents and Cypher stents both showed significant deformation (P<.0001 and P=.045, respectively) adjacent to the ostium, whereas only a minimal decrease of luminal area was observed with the Tsunami stent. In the central and distal parts of each stent, the decrease of luminal area was minimal and no differences were noted among the three types. Sudden fracture of a Cypher stent strut occurred during the experiment. CONCLUSION Differences of structural characteristics influence permanent plastic deformation at sites where continuous stress occurs, such as the coronary ostium. A more elastic design may show better resistance to such stress.

Endovascular treatment of innominate artery stenosis via the bilateral brachial approach

Endovascular treatment (stenting) has evolved as an effective and safe treatment modality for symptomatic subclavian and innominate artery disease. Most of these patients have comorbid conditions associated with atherosclerotic vascular disease, which is responsible for the access site and increased difficulty of procedure. We report a case of symptomatic innominate artery stenosis with concomitant atherosclerotic disease of the abdominal aorta successfully treated with using coronary devices and the pull-through technique via the bilateral brachial approach.