Sandhu, Gurpreet S.

Objective There is a paucity of data on the impact of complete revascularisation (CR) following percutaneous coronary intervention (PCI) among patients with diabetes with multivessel coronary disease. In this study, we assess the impact of CR, using a relatively simple anatomical definition, on long-term outcomes (median follow-up 7.9 years) in patients with diabetes, and compare with patients without diabetes. Methods 5350 patients with multivessel disease (coronary stenoses ≥70% in ≥2 major epicardial arteries) who underwent PCI between January 1997 and June 2011 were included. Patients were divided into 4 groups according to diabetes and CR status (absence of residual coronary stenosis in major, predominantly proximal, epicardial segments according to Coronary Artery Surgery Study (CASS) classification). Results Patients with diabetes and patients with incomplete revascularisation (IR) had more adverse clinical and angiographic characteristics. IR was frequent in patients with diabetes, and was marginally more common than in patients without diabetes (47% vs 44%, p<0.001). Patients with diabetes and patients without diabetes had higher mortality rates after IR than after CR (HR 1.56 (95% CI (1.39 to 1.85), p<0.001 for patients with diabetes and 1.70 (95% CI (1.50 to 1.92), p<0.001) in patients without diabetes). However, the absolute risk was higher for patients with diabetes (5-year mortality: IR 35.8%, CR 21.2%) than in patients without diabetes (5-year mortality: IR 22.2%, CR 14.1%). In a multivariable model, IR and diabetes mellitus were independent predictors of total mortality. This effect was present in the bare metal stent and drug-eluting stent eras and in patients with stable disease and acute coronary syndromes. Conclusions CR is associated with lower long-term mortality in patients with diabetes and patients without diabetes. However the difference was significantly greater in patients with diabetes compared with patients without diabetes.

Background: The addition of electroanatomic mapping to a standard echo-guided endomyocardial biopsy could identify areas of abnormal pathology and increase the diagnostic yield of the procedure. Methods and results: In this demonstration of a novel technique, a 45-year-old woman with clinical suspicion for cardiac sarcoidosis underwent right ventricular bipolar electroanatomical mapping with identification of areas of signal fractionation and low voltage. A bioptome, configured to record an electrogram from the tip, was then visualized on the three-dimensional electroanatomic mapping (3DEAM) system, and directed to these areas. The biopsy was assisted by the use of a steerable introducer sheath, and by recording unipolar and extended bipolar signals from the bioptome tip. A prominent change in the signal was detected by the electrode at the bioptome tip when the jaws closed on the endomyocardial tissue. Patient tolerated the procedure without complications, and the biopsied samples were appropriate for pathological analysis. Conclusions: Using existing technology, the 3DEAM, which integrates unipolar and bipolar signal from the bioptome tip, is feasible, and can be safely added to a standard echocardiographically guided endomyocardial biopsy. Future studies should investigate whether such a technique could increase the safety and diagnostic yield of endomyocardial biopsies in patients with suspected cardiomyopathies.

BackgroundWe sought to determine the utility of a magnetic navigation system (MNS) in treating a variety of coronary artery lesions including those that could not be revascularized with standard percutaneous coronary intervention (PCI). MNS may add value in the treatment of tortuous arteries and bifurcation lesions; however its widespread adoption has lagged because of cost and a lack of clear advantage over conventional PCI. We performed a retrospective analysis to determine whether MNS improved procedural success for highly complex lesions.Methods and ResultsOne hundred and forty‐eight patients underwent treatment with MNS at Mayo Clinic, Rochester. Clinical data, angiographic and procedural characteristics, lesion crossing success and outcomes were reviewed. Overall 133 patients underwent successful revascularization with 87% (143) of 164 lesions crossed using MNS alone. Another six lesions required a combination of MNS and conventional devices resulting in overall success of 91% (149/164). Eighteen complex lesions had previously failed PCI and 12 (67%) were successfully treated with MNS. Success after failed PCI was higher (88%) when a frequent user operated MNS, but occasional users also noted incremental success (30%). Twenty‐five chronic total occlusions were included amongst these 164 lesions, with observed antegrade MNS lesion crossing rates of 78% for regular and 14% for occasional users.ConclusionsMNS is a useful adjunct to performance of PCI. This specialized technology has a clear learning curve and can facilitate treatment of highly complex lesions. © 2013 Wiley Periodicals, Inc.

Background— High sensitivity C-reactive protein (hsCRP) has been identified as a predictor of adverse cardiovascular outcomes. Whether hsCRP is a useful biomarker for risk stratification in contemporary percutaneous coronary intervention remains unknown. Methods and Results— We conducted a prospective study among 513 patients undergoing non-emergency percutaneous coronary intervention and examined the relationship between pre- and postprocedural hsCRP levels and outcomes. The patients were divided according to the median preprocedural hsCRP level (0.3 mg/dL). Patients with high hsCRP had significantly more adverse clinical characteristics. Preprocedural hsCRP level was an independent predictor of periprocedural myocardial infarction (odds ratio per doubling of hsCRP 1.15 [95% confidence interval, 1.01–1.31]; P =0.038). Unadjusted mortality (29.7% versus 9.9%; P <0.001) and the combined end point of death or myocardial infarction (36.5% versus 16.0%, P <0.001) during a follow-up of 5 years were markedly greater in patients with high preprocedural hsCRP. Similar relationships existed for postprocedural hsCRP. However, after multivariable adjustment, neither preprocedural hsCRP levels (hazard ratio per doubling 0.96 [0.92, 1.00]; P =0.066) nor postprocedural hsCRP levels (hazard ratio 0.98 [0.94, 1.02]; P =0.27) were significantly associated with mortality. Conclusions— High hsCRP is associated with a greater independent risk of periprocedural myocardial infarction, as defined by the universal definition, but is not an independent determinant of mortality after percutaneous coronary intervention. Our findings suggest that routine measurement of hsCRP in patients undergoing percutaneous coronary intervention in contemporary practice is unlikely to be beneficial.

Background— Clinical outcomes after stent placement in patients with a history of metal allergy remain incompletely understood. We performed a single-center retrospective study to evaluate such outcomes. Methods and Results— Twenty-nine allergic patients who underwent coronary stent implantation were compared with a nonallergic group (n=250) matched for demographics and a propensity score for allergy to metal. Hypersensitivity to nickel was reported in 26 of 29 and chromium in 9 of 29. Patch testing performed in 11 of 29 patients was positive in all. Comparing allergy versus control subjects, there were no differences in number of segments treated (1.4±0.7 versus 1.5±0.7), stents placed (1.7±1.1 versus 1.6±0.9), and frequency of drug-eluting stent usage (52% versus 60%). In-hospital death (0% versus 0%), myocardial infarction (MI, 4% versus 3%, P =0.27), and 30-day death (3% versus 0%, P =0.53) and MI (3% versus 4%, P =0.71) were statistically similar. There were no differences in 4-year death (12% versus 13%), target lesion revascularization (TLR, 13 versus 17%, P =0.54), or death/MI/TLR (24% versus 34%, P =0.20). Clinically driven repeat angiography in 12 of 29 allergy patients revealed binary restenosis rates of 27% in bare metal stents and 0% in drug-eluting stents, with mean diameter in-stent restenosis of 36% and 8%, respectively. There was no change in circulating eosinophil and lymphocyte counts after stenting in the allergy group (0.19–0.20, P =0.67, and 1.90–1.79, P =0.59, respectively). Conclusions— A history of metal allergy was not associated with adverse early or late outcomes in this single-center study.

Background— Hematopoiesis originates from the dorsal aorta during embryogenesis. Although adult blood vessels harbor progenitor populations for endothelial and smooth muscle cells, it is not known if they contain hematopoietic progenitor or stem cells. Here, we hypothesized that the arterial wall is a source of hematopoietic progenitor and stem cells in postnatal life. Methods and Results— Single-cell aortic disaggregates were prepared from adult chow-fed C57BL/6 and apolipoprotein E–null (ApoE −/− ) mice. In short- and long-term methylcellulose-based culture, aortic cells generated a broad spectrum of multipotent and lineage-specific hematopoietic colony-forming units, with a preponderance of macrophage colony-forming units. This clonogenicity was higher in lesion-free ApoE −/− mice and localized primarily to stem cell antigen-1–positive cells in the adventitia. Expression of stem cell antigen-1 in the aorta colocalized with canonical hematopoietic stem cell markers, as well as CD45 and mature leukocyte antigens. Adoptive transfer of labeled aortic cells from green fluorescent protein transgenic donors to irradiated C57BL/6 recipients confirmed the content of rare hematopoietic stem cells (1 per 4 000 000 cells) capable of self-renewal and durable, low-level reconstitution of leukocytes. Moreover, the predominance of long-term macrophage precursors was evident by late recovery of green fluorescent protein–positive colonies from recipient bone marrow and spleen that were exclusively macrophage colony-forming units. Although trafficking from bone marrow was shown to replenish some of the hematopoietic potential of the aorta after irradiation, the majority of macrophage precursors appeared to arise locally, suggesting long-term residence in the vessel wall. Conclusions— The postnatal murine aorta contains rare multipotent hematopoietic progenitor/stem cells and is selectively enriched with stem cell antigen-1–positive monocyte/macrophage precursors. These populations may represent novel, local vascular sources of inflammatory cells.

AbstractThe antithrombotic surface of endothelium is regulated in a coordinated manner. Tissue factor pathway inhibitor (TFPI) localized at the endothelial cell surface regulates the production of FXa by inhibiting the TF/VIIa complex. Systemic homozygotic deletion of the first Kunitz (K1) domain of TFPI results in intrauterine lethality in mice. Here we define the cellular sources of TFPI and their role in development, hemostasis, and thrombosis using TFPI conditional knockout mice. We used a Cre-lox strategy and generated mice with a floxed exon 4 (TFPIFlox) which encodes for the TFPI-K1 domain. Mice bred into Tie2-Cre and LysM-Cre lines to delete TFPI-K1 in endothelial (TFPITie2) and myelomonocytic (TFPILysM) cells resulted in viable and fertile offspring. Plasma TFPI activity was reduced in the TFPITie2 (71% ± 0.9%, P < .001) and TFPILysM (19% ± 0.6%, P < .001) compared with TFPIFlox littermate controls. Tail and cuticle bleeding were unaffected. However, TFPITie2 mice but not TFPILysM mice had increased ferric chloride–induced arterial thrombosis. Taken together, the data reveal distinct roles for endothelial- and myelomonocytic-derived TFPI.

Background— Synthetic vascular grafts cannot be used in small vessels because of graft failure caused by thrombosis and neointima formation. Rapid endothelialization may overcome this limitation. We hypothesized that a magnetic graft would be able to capture and retain endothelial cells labeled with paramagnetic particles. Methods and Results— Porcine blood derived endothelial cells were allowed to endocytose superparamagnetic iron oxide microspheres. Cell survival was assessed by trypan blue exclusion and demonstrated a dose-dependent cell survival of 75% to 95%. A flexible magnetic sheet was annealed to the external surface of a knitted Dacron graft. Labeled cells (10 6 /mL) were placed within the graft for 5 minutes. Confocal and electron microscopy confirmed uniform cell capture at the magnetized surface. The effect of shear forces on the adherent cells was evaluated in a flow chamber. The cells remained attached at rates up to 300 mL/min, with cell loss commencing at 400 mL/min. Prototype magnetic grafts were implanted in porcine carotid arteries. Labeled cells were placed within the graft for 10 minutes at the time of implantation. The grafts were evaluated after one day and uniform cell coverage was noted on the magnetized surface. In comparison, relatively few labeled cells were seen attached to a nonmagnetized surface. Conclusions— Magnetic forces can be used to rapidly cover a vascular graft with paramagnetically labeled cells. This biophysical interaction is sufficient to retain cells in the presence of blood flow. Applications of this technique may include rapid endothelialization of synthetic vascular grafts and dialysis fistulas.