Circulating very small embryonic-like stem cells in cardiovascular disease

Very small embryonic-like cells (VSELs) are a population of stem cells residing in the bone marrow (BM) and several organs, which undergo mobilization into peripheral blood (PB) following acute myocardial infarction and stroke. These cells express markers of pluripotent stem cells (PSCs), such as Oct-4, Nanog, and SSEA-1, as well as early cardiac, endothelial, and neural tissue developmental markers. VSELs can be effectively isolated from the BM, umbilical cord blood, and PB. Peripheral blood and BM-derived VSELs can be expanded in co-culture with C2C12 myoblast feeder layer and undergo differentiation into cells from all three germ layers, including cardiomyocytes and vascular endothelial cells. Isolation of VSLEs using fluorescence-activated cell sorting multiparameter live cell sorting system is dependent on gating strategy based on their small size and expression of PSC and absence of hematopoietic lineage markers. VSELs express early cardiac and endothelial lineages markers (GATA-4, Nkx2.5/Csx, VE-cadherin, and von Willebrand factor), SDF-1 chemokine receptor CXCR4, and undergo rapid mobilization in acute MI and ischemic stroke. Experiments in mice showed differentiation of BM-derived VSELs into cardiac myocytes and effectiveness of expanded and pre-differentiated VSLEs in improvement of left ventricular ejection fraction after myocardial infarction.

Diagnostic value of flow mediated dilatation measurement for coronary artery lesions in men under 45 years of age

BACKGROUND

In those without symptoms of coronary artery disease (CAD), the incidence of coronary events is still high. The aim of this study was to evaluate whether flow mediated dilatation (FMD) is a useful tool in identifying those with CAD in who are under 45 years of age.

METHODS AND RESULTS

Seventy five men below 45 years of age, hospitalized in order to perform elective coronary angiography, were enrolled into the study. Based on coronary angiography findings, they were divided into two groups: study group (Group A, n = 55) with obstructive coronary lesions and the control group (Group B, n = 20) without significant lesions in coronary arteries. In all subjects atherosclerosis risk factors were analyzed. Endothelial dysfunction was assessed in ultrasound via FMD. FMD was significantly lower in the study group than in the control group (3.92 +/- 1.1 vs 6.51 +/- 1.1, p < 0.001). FMD, as well as age, diabetes and positive family history, appeared to be statistically significant CAD risk factors. AUROC for FMD was 0.957 (p < 0.001), meaning this model had an almost complete ability to predict the presence of CAD. AUROC for CAD diagnosis on the basis of significant clinical parameters was 0.992 (p < 0.001), also representing almost complete ability of this model to identify asymptomatic subjects with CAD risk.

CONCLUSIONS

The evaluation of endothelial function by the use of FMD in the population of men below 45 years of age with diabetes and positive family history can help in identifying subjects at high risk of coronary artery disease.

Plasma adiponectin in patients with acute myocardial infarction treated with percutaneous coronary intervention

BACKGROUND

Even up-to-date reperfusion therapy using primary percutaneous intervention (PCI) in acute myocardial infarction does not result in improvement of the left ventricular (LV) function in all patients. Cellular myoblasty, a novel method using mononuclear bone marrow cells (BMC), can be applied in the infarcted myocardium area to stimulate regeneration and to limit the organ damage. However, the impact of intracoronary BMC administration on the effect of PCI is not clear.

AIM

To assess angiographic outcomes in patients with anterior myocardial infarction and LV dysfunction, undergoing intracoronary BMC administration after a successful primary PCI.

METHODS

The study group consisted of 40 patients (mean age 56.2 years) with LV ejection fraction below 40%, in whom 20 ml of BMC were administered to the infarct-related artery (IRA) distally to the occlusion. The control group comprised 25 age- and sex-matched patients with similar values of LV ejection fraction undergoing bare metal stenting of IRA without BMC administration. Quantitative coronary angiography was performed 6 months later to assess IRA patency.

RESULTS

The reference diameter of the stented artery decreased in the study group from 3.22 +/- 0.28 mm to 3.16 +/- 0.18 mm (p < 0.05) and in the control group from 3.22 +/- 0.31 mm to 3.15 +/- 0.28 mm (p < 0.082); also in the area of the implanted stent the diameter decreased from 3.57 +/- 0.21 mm to 2.96 +/- 0.79 mm in the study group vs. 3.48 +/- 0.22 mm to 3.01 +/- 0.35 mm in the control group. For lumen diameter measured 10 mm distally to the stent, the diameter loss was similar in both groups. In 6 patients from the BMC treated group and in 3 patients from the control group there was asymptomatic lumen reduction > 70% (NS).

CONCLUSION

The results of our study show that BMC administration into IRA is safe. The degree of lumen loss in the stent area was larger in the BMC group than in the control group. There was no significant difference in the lumen change distally to the stent; the artery diameter loss in both groups was similar, and the improvement in LV ejection fraction was greater in the BMC-treated group.

Early and long-term outcomes after surgical and percutaneous myocardial revascularization in patients with non-ST-elevation acute coronary syndromes and unprotected left main disease

Surgical myocardial revascularization (CABG) in patients with unprotected left main coronary artery disease (ULMCA) is a Class I recommendation in the AHA/ACC guidelines, however it is associated with increased perioperative risk in non-ST elevation acute coronary syndromes (NSTE-ACS). The aim of this study was to compare early and late results after percutaneous coronary intervention (PCI) and CABG in this cohort of patients.

METHODS

A multicenter prospective registry included 138 patients with patent but severely narrowed (> 50%) ULMCA disease and NSTE-ACS diagnosed between January 2005 and April 2007. After emergent coronary angiography, 63 patients underwent PCI, whiles 75 were assigned for CABG.

RESULTS

Groups were comparable with regard to sex, age and prevalence of diabetes mellitus (DM). They had similar left ventricular ejection fraction, SYNTAX Score and incidence of distal LM stenosis. However, PCI patients were at higher surgical risk (Euroscore 8.7 +/- 3.7 vs. 7.4 +/- 3.0; p = 0.02) and myocardial infarction incidence (28% vs. 14%; p = 0.07). The 30-day mortality was 1.5% after PCI vs. 12% after CABG (p = 0.043) and major adverse cardiovascular and cerebrovascular events (MACCE) were 3.2% vs. 14.7%, respectively (p = 0.04). After 12 months, there were 4 deaths in the PCI group and 12 deaths in the CABG group (6.3% vs. 16%; p = 0.14). There was no difference in MACCE (9.5% vs. 9.3% p = ns). Kaplan-Meier analysis revealed a trend toward better survival after PCI (p = 0.07). Revascularization with CABG and a Euroscore > 5 were the independent risk factors influencing early survival, while a Euroscore > 6 was the independent predictor of late mortality.

CONCLUSIONS

PCI is a reasonable alternative to CABG in patients with NSTE-ACS and ULMCA stenosis.

Plasma levels of C-reactive protein and interleukin-10 predict late coronary in-stent restenosis 6 months after elective stenting

BACKGROUND

In-stent restenosis (ISR) is one of the major limitations of percutaneous coronary intervention (PCI).

AIM

To evaluate the relationship between the levels of hs-CRP, IL-6, IL-10 and intimal hyperplasia six months after coronary bare metal stent (BMS) implantation.

METHODS

The study population consisted of 73 consecutive patients who underwent bare metal stent implantation into narrowed coronary segments. A total of 74 stents were implanted. Angiographic study after six months, together with evaluation of serum level of IL-6 (pg/ml), IL-10 (pg/ml), hs-CRP (microg/ml), fasting insulin (microIU/ml) and glucose (mg%) was performed. Insulin sensitivity was calculated using the HOMA-IR formula. The QCA analysis of stented segments was performed at baseline, after intervention and at six-month follow-up.

RESULTS

Restenosis at six months occurred in 10 patients (13.7%). The mean % diameter stenosis at follow-up was 27.8 +/- 19% and late loss was 0.81 +/- 0.6 mm. We found a correlation between late loss and serum hs-CRP, IL-6 and IL-10 concentration. There was no correlation between the lipid profiles, insulin levels and HOMA-IR and re-narrowing of the stented segments. Patients with restenosis were characterised by significantly higher serum concentration of CRP (2.04 +/- 3.4 vs. 10.38 +/- 6.7 microg/ml, p = 0.0036), IL-6 (14.98 +/- 8.3 vs. 5.70 +/- 5.5 pg/ml, p = 00062), and fasting glucose (184.0 +/- 50.5 vs. 107.5 +/- 40.4 mg%, p = 0.0051), as well as lower IL-10 levels (1.25 +/- 0.6 vs. 4.85 +/- 4.9 pg/ml, p = 0.0000). The ROC analysis indicated that CRP (> 2.86 microg/ml), IL-6 (> 6.24 pg/ml) and IL-10 (< 1.7 pg/ml) values predicted the restenosis with reasonable accuracy. A multiple logistic regression model identified CRP and IL-10 levels as independent predictors of restenosis.

CONCLUSION

We demonstrated that elevated inflammatory markers 6 months after PCI are associated with late angiographic in-stent restenosis.

Mobilization of bone marrow-derived Oct-4+ SSEA-4+ very small embryonic-like stem cells in patients with acute myocardial infarction

OBJECTIVES

This study sought to assess of the mobilization of nonhematopoietic very small embryonic-like stem cells (VSELs) in acute myocardial infarction (MI).

BACKGROUND

Acute MI induces mobilization of bone marrow stem cells. Recently, a rare population of VSELs, expressing markers of embryonic pluripotent stem cells (PSCs), was identified in adult murine bone marrow and human umbilical cord blood.

METHODS

Thirty-one patients with acute MI and 30 healthy subjects were enrolled. Blood was sampled on admission, after 24 h, and 5 days later. Erythrocytes were lysed and lin(-)CD45(-) VSELs were isolated using a live cell sorting system (FACSAria, Beckton Dickinson, San Jose, California).

RESULTS

In healthy subjects the median number of circulating VSELs was very low (median 0.8 [range 0 to 1.3]) cells/microl. In acute MI, VSELs were mobilized early (median 2.7 [range 0.2 to 3.9] cells/microl; p < 0.001) and remained elevated after 24 h and 5 days (median 4.7 [range 0.2 to 6.4] cells/microl; p < 0.003, and median 2.6 [range 0.3 to 3.6] cells/microl; p < 0.03, respectively). The mobilization of VSEL was significantly reduced in patients older than 50 years and with diabetes in comparison with younger and nondiabetic patients. Circulating VSELs were small (7 to 8 microm) and enriched in the messenger ribonucleic acid of PSC markers (Oct-4, Nanog), cardiac lineage (GATA-4, Nkx2.5/Csx, MEF2C), and endothelial (VE-cadherin) markers. The presence of PSC markers (Oct-4, SSEA-4) and the chemokine receptor CXCR4 in circulating VSELs was confirmed at the protein level by immunofluorescent staining and ImageStream system (Amnis Corporation, Seattle, Washington) analysis.

CONCLUSIONS

Acute MI induced mobilization of VSELs expressing pluripotent markers, early cardiac and endothelial markers, and chemokine receptor CXCR4.

Coronary artery visualization using a 64-row multi-slice computed tomography in unselected patients with definite or suspected coronary artery disease: a comparison with invasive coronary angiography

BACKGROUND

Multi-slice computed tomography (MSCT) is becoming an increasingly acknowledged means of visualizing coronary arteries. The accuracy of 64-MSCT is still a subject of clinical evaluation. Our study, performed with a 64-slice scanner, was intended to assess the concordance of coronary artery lumen visualization in MSCT and invasive coronary angiography (ICA), both in post-revascularization and previously medically treated patients.

METHODS

We examined data from 73 patients (31 women, 42 men, mean age 59 years) referred to our hospital in 2006 and 2007 who underwent MSCT and subsequent ICA. Twenty two patients had a history of previous revascularization. Of the remaining 51 patients with intermediate coronary artery disease probability, the indication for 64-MSCT was suspicion of coronary artery disease. MSCT coronary angiography was performed with Aquilion 64 scanner (Toshiba, Japan). We evaluated 15 segments of four native coronary arteries (RCA, LM, LAD and Cx in all patients plus 11 arterial and 22 venous conduits). The cut-off value for significant stenosis was the lumen cross section area reduction exceeding 50%, regardless of segment.

RESULTS

Regarding native arteries, MSCT and ICA findings were coherent in 80.8% of all patients, 93.8% of vessels, and 98.4% of segments. MSCT coronary stent patency evaluation was 90.9% correct. The by-pass grafts evaluation was entirely concordant in both methods. The respiratory and heart rate variability artifacts hindered the MSCT analysis in ten patients (13.7%). The artifacts occurrence in misinterpreted studies was nearly two-fold higher than in those that were coherent (21.4% vs. 11.9%).

CONCLUSIONS

We concluded that a reliable evaluation of the coronaries by means of 64-MSCT is feasible both in patients with suspected coronary artery disease and those with definite coronary artery disease who had previous coronary intervention. Patient selection and co-operation is necessary to avoid respiratory and heart rate variability artifacts that may hinder analysis.

Coronary artery bypass grafting in patients with relatively recent previous stent implantation: three years follow-up results

BACKGROUND

An increasing number of patients who undergo coronary artery bypass grafting(CABG) have a history of coronary stent implantation. This study aims to assess perioperative and medium-term follow-up outcomes in patients in whom CABG was preceded by coronary stent implantation within two years before operation.

METHODS

One hundred and sixty two patients undergoing CABG after previous stent placement (PCI + CABG group) were compared to 149 who had CABG without PCI in the past (CABG group). Clinical, angiographic and perioperative outcome data were compared. The three year follow-up comprised data on number of deaths and the presence of anginal symptoms.

RESULTS

In both groups the extent of coronary artery disease was comparable, but more patients in the PCI + CABG group had a history of myocardial infarction. Perioperative outcome data did not differ between the groups except for a higher number of vessels considered infarct-related grafted in the CABG group. Patients operated on up to three months after PCI had more extensive coronary heart disease than those operated on later. They also had a significantly shorter operation time. This group also showed a trend towards less postoperative bleeding, less rethoracotomy and less low cardiac output syndrome. In a three year follow-up, 48 (30%) patients in the PCI + CABG group reported presence of angina compared to 28 (19%) in the CABG group (p = 0.04).

CONCLUSIONS

Previous PCI does not significantly influence the CABG outcome. In mediumterm follow-up, freedom from anginal symptoms is less likely in patients in whom CABG was preceded by stent implantation.

Early and late outcomes of percutaneous transluminal angioplasty of cephalad arteries

BACKGROUND

Efficacy of carotid endarterectomy (CEA) in prevention of stroke in patients with carotid artery stenosis has been confirmed in randomised trials. Carotid artery stenting (CAS) is a routine clinical practice and recent results of CAS are not worse than CEA. Moreover, percutaneous transluminal angioplasty (PTA) techniques allow other cephalad arteries to be dilated.

AIM

To assess early and long-term outcome of PTA of cephalad arteries and to determine risk factors of early and late major adverse cardiovascular and cerebral events (MACCE).

METHODS

The study group consisted of 223 consecutive patients (151 males, 67.7%, mean age 65.3+/-8.6) in whom 256 PTA procedures of cephalad arteries were performed. Two hundred and forty-two internal carotid, 7 common carotid and 15 vertebral arteries were dilated. Thirty-four patients underwent one-stage carotid and coronary procedures, while in 46 patients one-stage carotid and peripheral procedures were performed. Neuroprotection with a distal protection device was used in 51.5% of cases. The procedures were divided into two groups: with high (n=181) and low (n=75) risk of cardiovascular events. Early and late events were recorded and analysed subsequently.

RESULTS

In hospital 30-day MACCE occurred in 12 (4.6%) patients, including 7 (2.7%) strokes, 3 (1.1%) myocardial infarctions and two (0.8%) deaths. Transient ischaemic attacks were observed in 8 patients, pulmonary oedema in 3 cases, as well as a single episode of retinal artery embolisation and acute renal insufficiency. The incidence of 30-day MACCE was not significantly higher in the high-risk group (6.07 vs. 1.33%; NS), but the risk of any adverse event was significantly higher (p=0.03). There was no difference in stroke incidence between procedures with or without neuroprotection (2.27 vs. 3.22%; NS). There was no difference in risk of MACCE between angioplasty of cephalad artery and one-stage cephalad and coronary artery angioplasty procedure (3.6 vs. 5.5%; NS). During 50.3+/-20 months of follow-up there were 16 (7.1%) deaths, 9 (3.5%) strokes and 6 (2.3%) re-stenoses confirmed angiographically. One-year total survival and one-year MACCE-free survival rates according to the Kaplan-Meier analysis were 94.9% and 89.0%, showing a trend towards better outcome in the low-risk group (F-Cox=2.46; p=0.19 and F-Cox=2.17; p=0.09 respectively).

CONCLUSIONS

Percutaneous transluminal angioplasty of cephalad arteries is safe and feasible, with a low periprocedural complication rate and good late outcome. Carotid artery stenting is an alternative method to CEA.