A case of active peri-stent inflammation after sirolimus-eluting stent implantation

Clinical outcomes of patients with coronary artery aneurysm after the first generation drug-eluting stent implantation

OBJECTIVES

We sought to investigate the long-term clinical outcomes of patients with coronary artery aneurysm (CAA) after drug-eluting stent (DES) implantation, compared with patients without CAA.

BACKGROUND

CAA developed after DES implantation is a rare but associated with poor clinical outcome.

METHODS

We retrospectively compared 78 patients with CAA after DES implantation with 269 patients without CAA who underwent DES implantation for complex lesions (controls). The primary endpoint was defined as major adverse cardiac events (MACE), the composite of all-cause death, nonfatal myocardial infarction (MI), and target lesion revascularization (TLR).

RESULTS

Morphologically, CAAs were saccular (32%), fusiform (13%), or microform (55%). The stent types involved were Cypher (n = 56, 71.8%) and Taxus (n = 22, 28.2%). During a median follow-up period of 1164 days, the incidence of MACE was significantly higher in the CAA group (26.9 vs. 2.2%, P < 0.001); the difference was driven mainly by nonfatal MI (11.5 vs. 0%, P < 0.001) and TLR (20.5 vs. 1.9%, P < 0.001). The incidence of stent thrombosis was higher in the CAA group (12.8 vs. 0.74%, P < 0.001), irrespective of the maintenance of dual antiplatelet therapy. In the CAA group, Cox regression analysis showed significantly higher hazard ratios of CAA for MACE during the follow-up period. Further analyses after propensity-score matching of 65 pairs also showed similar results.

CONCLUSIONS

The incidence of MACE was higher in patients with CAA compared with patients without CAA after DES implantation. This difference was driven by TLR and nonfatal MI and widened over time.

Application of an enhanced device to transluminal retrieval of malappositioned coronary stents: An experimental study

OBJECTIVES

This study investigated the application of a novel enhanced device to retrieval of deployed stents in a porcine coronary model.

BACKGROUND

Recurrence of in-stent restenosis and stent thrombosis still remains to be resolved. Under these conditions, it is sometimes necessary to retrieve malfunctional stents responsible for thrombosis. However, few data exist regarding the feasibility and safety of retrieval device use in previously deployed coronary stents.

METHODS

We have developed an enhanced device consisting of an asymmetric forceps, conducting shaft (1.6 mm diameter, 150 cm length), and control handle. Bare-metal stents (3 mm diameter) were implanted in four pigs to create a malapposition model. Coronary artery injury was evaluated by intravascular ultrasound (IVUS) and histological imaging on the first and 14th days.

RESULTS

The device was delivered to the coronary artery using the existing catheter (7 Fr). After opening the forceps, the blade was forced into the space between the vessel wall and the stent, and the stent struts were then grasped with the forceps. This was then pulled back into the catheter, still grasping the stent struts with the forceps. All stents were successfully retrieved by this method (n = 4). On the first day, no apparent vessel wall injury was detectable by IVUS, although histological findings revealed damage to endothelial monolayer on retrieval of deployed stent. On the 14th day, mild intimal thickening was observed by IVUS and histology.

CONCLUSIONS

These results demonstrate that the present device can be applied to transluminal retrieval of acquired malappositioned coronary stents.

Early endothelialization associated with a biolimus A9 bioresorbable polymer stent in a porcine coronary model

Although Nobori^®, with a bioresorbable polymer and biolimus A9 abluminal coating, has unique characteristics, few data exist regarding endothelialization early after implantation. Fifteen Nobori^® and 14 control bare-metal stents (S-stent™) were implanted in 12 pigs. Histopathology of stented segments, inflammation, and intimal fibrin content was evaluated on the 2nd and 14th day after implantation. On the 2nd day, endothelial cells were morphologically and immunohistologically confirmed on the surface of both stents, although some inflammatory cells might be involved. Stent surface endothelialization evaluated with a scanning electron microscope showed partial cellular coverage in both stents. On the 14th day, neointimal thickness and percentage of the neointimal area were significantly lower in Nobori^® than in S-stent™ (51.4 ± 4.5 vs. 76.4 ± 23.6 µm, p < 0.05 and 10.8 ± 2.6 vs. 14.1 ± 4.2%, p < 0.01). No significant differences were found in these parameters on the 2nd day (17.3 ± 14.9 vs. 26.7 ± 13.6 µm and 3.7 ± 3.0 vs. 6.7 ± 3.7%), in inflammatory and intimal fibrin content scores. These results demonstrate that endothelialization could occur early after Nobori^® implantation with similar inflammatory reaction to bare-metal stents, probably contributing to low frequency of in-stent thrombosis and restenosis.

A case of IgG4-related lymphadenopathy, pericarditis, coronary artery periarteritis and luminal stenosis

Immunoglobulin G4 (IgG4)-related disease is an emerging new clinicopathological disorder that is characterized by elevation of serum IgG4 levels and histological findings of IgG4-positive plasmacytic infiltration. IgG4-related disease may appear synchronously or metachronously in a wide variety of organs. The current patient was found to have pericardial effusion and retroperitoneal fibrosis. He was subsequently diagnosed with coronary artery stenosis. (18)F-FDG positron emission tomography showed enhanced FDG uptake in lymph nodes as well as pericardial and peri-aortic tissue. Histopathology of the mediastinal lymph node showed the infiltration of numerous IgG4-positive cells, leading to the diagnosis of IgG4-related lymphadenopathy with pericardial and periarterial involvement.