Our preliminary experience suggests that coronary PLLA biodegradable stents are feasible, safe, and effective in humans. Long-term follow-up with more patients will be required to validate the long-term efficacy of PLLA stents.

Background-The purpose of this study was to evaluate the long-term safety of the Igaki-Tamai stent, the first-in-human fully biodegradable coronary stent made of poly-l-lactic acid. Methods and Results-Between September 1998 and April 2000, 50 patients with 63 lesions were treated electively with 84 Igaki-Tamai stents. Overall clinical follow-up (Ͼ10 years) of major adverse cardiac events and rates of scaffold thrombosis was analyzed together with the results of angiography and intravascular ultrasound. Major adverse cardiac events included all-cause death, nonfatal myocardial infarction, and target lesion revascularization/target vessel revascularization. During the overall clinical follow-up period (121Ϯ17 months), 2 patients were lost to follow-up. There were 1 cardiac death, 6 noncardiac deaths, and 4 myocardial infarctions. Survival rates free of all-cause death, cardiac death, and major adverse cardiac events at 10 years were 87%, 98%, and 50%, respectively. The cumulative rates of target lesion revascularization (target vessel revascularization) were 16% (16%) at 1 year, 18% (22%) at 5 years, and 28% (38%) at 10 years. Two definite scaffold thromboses (1 subacute, 1 very late) were recorded. The latter case was related to a sirolimus-eluting stent, which was implanted for a lesion proximal to an Igaki-Tamai stent. From the analysis of intravascular ultrasound data, the stent struts mostly disappeared within 3 years. The external elastic membrane area and stent area did not change. Conclusion-Acceptable major adverse cardiac events and scaffold thrombosis rates without stent recoil and vessel remodeling suggested the long-term safety of the Igaki-Tamai stent. (Circulation. 2012;125:2343-2352.)

The baseline data from GLORIA-AF phase 2 demonstrate that in newly diagnosed nonvalvular atrial fibrillation patients, NOAC have been highly adopted into practice, becoming more frequently prescribed than VKA in Europe and North America. Worldwide, however, a large proportion of patients remain undertreated, particularly in Asia and North America. (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients With Atrial Fibrillation [GLORIA-AF]; NCT01468701).

Although biocompatibility of biodegradable stents is controversial, stents made of high molecular weight poly‐l‐lactic acid (PLLA) are thought to be the most promising. We investigated the biocompatibility of PLLA stents histologically and angiographically in porcine coronary arteries. The Igaki‐Tamai stent is made of PLLA monofilaments (molecular mass 183 kD) with a zigzag helical coil design. Fourteen PLLA stents in 6 pigs and 9 Palmaz‐Schatz half stents in 9 pigs were implanted in 15 normocholesterolemic pigs. Stents were mounted on a delivery catheter, and were implanted percutaneously into coronary arteries. Coronary angiography was performed before and immediately after stenting, at 2 and 6 weeks in five PLLA pigs and nine Palmaz‐Schatz pigs. Histological studies were performed in PLLA pigs: 2 pigs at 2 weeks, 3 pigs at 6 weeks, and 1 pig at 16 weeks with hematoxylin‐eosin and elastica van Giesons stains. All PLLA stents were successfully delivered. No stent thrombosis was detected in either group. There were no significant differences in minimal lumen diameter (MLD) or percent diameter stenosis between the PLLA and Palmaz‐Schatz stent groups immediately after implantation, or at 2 or 6 weeks after implantation. Histological studies at 2, 6, and 16 weeks revealed no inflammation and minimal neointimal coverage on the PLLA stent struts. The PLLA stent maintained its structure for up to 16 weeks. These results suggest sufficient biocompatibility and strength of PLLA biodegradable stents in porcine coronary arteries. Clinical trial is now underway to validate the safety and usefulness of PLLA stents in humans.

To get superior guiding catheter support, we tried a new method called the anchor technique. By inflating a balloon in a nontarget vessel and holding its shaft with backward force while advancing another balloon, the anchor effect for the guiding catheter could be obtained and it appeared to be helpful for a balloon or a stent to cross the target lesion.

Despite technical and mechanical improvement in coronary stents the incidence of restenosis caused by in-stent neointimal hyperplasia remains high. Oral administration of numerous pharmacological agents has failed to reduce restenosis after coronary stenting in humans, possibly owing to insufficient local drug concentration. Therefore, drug-eluting stents were developed as a vehicle for local drug administration. The authors developed a new drug-eluting polymer stent that is made of poly-l-lactic acid polymer mixed with tranilast, an anti-allergic drug that inhibits the migration and proliferation of vascular smooth muscle cells induced by platelet-derived growth factor and transforming growth factor->1. Polymer stents might be superior to polymer-coated metallic stents as local drug delivery stents in terms of biodegradation and the amount of loaded drug. Drug-mixed polymer stents can be loaded with a larger amount of drug than can drug-coated metallic stents because the polymer stent struts can contain the drug. Clinical application is required to assess the safety and efficacy of drug-eluting polymer stents against stent restenosis.

While primary percutaneous coronary intervention (PCI) has significantly contributed to improve the mortality in patients with ST segment elevation myocardial infarction even in cardiogenic shock, primary PCI is a standard of care in most of Japanese institutions. Whereas there are high numbers of available facilities providing primary PCI in Japan, there are no clear guidelines focusing on procedural aspect of the standardized care. Whilst updated guidelines for the management of acute myocardial infarction were recently published by European Society of Cardiology, the following major changes are indicated; (1) radial access and drug-eluting stent over bare metal stent were recommended as Class I indication, and (2) complete revascularization before hospital discharge (either immediate or staged) is now considered as Class IIa recommendation. Although the primary PCI is consistently recommended in recent and previous guidelines, the device lag from Europe, the frequent usage of coronary imaging modalities in Japan, and the difference in available medical therapy or mechanical support may prevent direct application of European guidelines to Japanese population. The Task Force on Primary Percutaneous Coronary Intervention of the Japanese Association of Cardiovascular Intervention and Therapeutics (CVIT) has now proposed the expert consensus document for the management of acute myocardial infarction focusing on procedural aspect of primary PCI.

Objectives-We sought to evaluate the accuracy of standardized total plaque volume (TPV) measurement and low-density non-calcified plaque (LDNCP) assessment from coronary CT angiography (CTA) in comparison with intravascular ultrasound (IVUS).Methods-We analyzed 118 plaques without extensive calcifications from 77 consecutive patients who underwent CTA prior to IVUS. CTA TPV was measured with semi-automated software comparing both scan-specific (automatically derived from scan) and fixed attenuation thresholds. From CTA, %LDNCP was calculated voxels below multiple LDNCP thresholds (30, 45, 60, 75, and 90 Hounsfield units [HU]) within the plaque. On IVUS, the lipid-rich component was identified by echo attenuation, and its size was measured using attenuation score (summed Hidenari Matsumoto,