The effect of bioresorbable vascular scaffold implantation on distal coronary endothelial function in dyslipidemic swine with and without diabetes.

Background: We studied the effect of bioresorbable vascular scaffold (BVS) implantation on distal coronary endothelial function, in swine on a high fat diet without (HFD) or with diabetes (DM+HFD).

Methods: Five DM+HFD and five HFD swine underwent BVS implantation on top of coronary plaques, and were studied six months later. Conduit artery segments >5mm proximal and distal to the scaffold and corresponding segments of non-scaffolded coronary arteries, and segments of small arteries within the flow-territory of scaffolded and non-scaffolded arteries were harvested for in vitro vasoreactivity studies.

Time course of VCAM-1 expression in reperfused myocardial infarction in swine and its relation to retention of intracoronary administered bone marrow-derived mononuclear cells.

Background: Intracoronary infusion of autologous bone marrow-derived mononuclear cells (BMMNC), after acute myocardial infarction (AMI), has been shown to improve myocardial function. However, therapeutic efficacy is limited, possibly because cell retention rates are low, suggesting that optimization of cell retention might increase therapeutic efficacy. Since retention of injected BMMNC is observed only within infarcted, but not remote, myocardium, we hypothesized that adhesion molecules on activated endothelium following reperfusion are essential.

Intermittent pacing therapy favorably modulates infarct remodeling.

Despite early revascularization, remodeling and dysfunction of the left ventricle (LV) after acute myocardial infarction (AMI) remain important therapeutic targets. Intermittent pacing therapy (IPT) of the LV can limit infarct size, when applied during early reperfusion. However, the effects of IPT on post-AMI LV remodeling and infarct healing are unknown.

Coronary microvascular dysfunction after long-term diabetes and hypercholesterolemia.

Coronary microvascular dysfunction (CMD) has been proposed as an important component of diabetes mellitus (DM)- and hypercholesterolemia-associated coronary artery disease (CAD). Previously we observed that 2.5 mo of DM and high-fat diet (HFD) in swine blunted bradykinin (BK)-induced vasodilation and attenuated endothelin (ET)-1-mediated vasoconstriction.

VEGF165A microsphere therapy for myocardial infarction suppresses acute cytokine release and increases microvascular density but does not improve cardiac function.

Angiogenesis induced by growth factor-releasing microspheres can be an off-the-shelf and immediate alternative to stem cell therapy for acute myocardial infarction (AMI), independent of stem cell yield and comorbidity-induced dysfunction. Reliable and prolonged local delivery of intact proteins such as VEGF is, however, notoriously difficult. Our objective was to create a platform for local angiogenesis in human-sized hearts, using polyethylene-glycol/polybutylene-terephthalate (PEG-PBT) microsphere-based VEGF165A delivery.

Peripheral arterial tonometry cannot detect patients at low risk of coronary artery disease.

Background: Endothelial dysfunction precedes coronary artery disease (CAD) and can be measured by peripheral arterial tonometry (PAT). We examined the applicability of PAT to detect a low risk of CAD in a chest pain clinic.

Methods: In 93 patients, PAT was performed resulting in reactive hyperaemia (RHI) and augmentation (AIx) indices.

Early systemic microvascular damage in pigs with atherogenic diabetes mellitus coincides with renal angiopoietin dysbalance.

Background: Diabetes mellitus (DM) is associated with a range of microvascular complications including diabetic nephropathy (DN). Microvascular abnormalities in the kidneys are common histopathologic findings in DN, which represent one manifestation of ongoing systemic microvascular damage. Recently, sidestream dark-field (SDF) imaging has emerged as a noninvasive tool that enables one to visualize the microcirculation.

Evolution of reperfusion post-infarction ventricular remodeling: new MRI insights.

Background: Our current understanding is that left ventricular (LV) remodeling after acute myocardial infarction (AMI) is caused by expansion of the infarcted myocardium with thinning of the wall and eccentric hypertrophy of the remote myocardium. To study the geometric changes in the remodeling process after reperfused AMI we used cardiac magnetic resonance imaging (CMR).

Methods: Nine juvenile swine underwent a 120-min occlusion of the left circumflex coronary artery followed by reperfusion.

Serial measurement of hFABP and high-sensitivity troponin I post-PCI in STEMI: how fast and accurate can myocardial infarct size and no-reflow be predicted?

The objective of this study was to compare heart-specific fatty acid binding protein (hFABP) and high-sensitivity troponin I (hsTnI) via serial measurements to identify early time points to accurately quantify infarct size and no-reflow in a preclinical swine model of ST-elevated myocardial infarction (STEMI). Myocardial necrosis, usually confirmed by hsTnI or TnT, takes several hours of ischemia before plasma levels rise in the absence of reperfusion. We evaluated the fast marker hFABP compared with hsTnI to estimate infarct size and no-reflow upon reperfused (2 h occlusion) and nonreperfused (8 h occlusion) STEMI in swine.

Health-related quality of life in the elderly three years after percutaneous coronary intervention.

Aims: Long-term health-related quality of life (HRQOL) in the elderly after percutaneous coronary intervention (PCI) is unknown. We 1) compared HRQOL of elderly (≥70 years) with younger patients (<70 years) at 6, 12, 36 months post-PCI, and 2) examined whether predictors of impaired HRQOL 36 months post-PCI differed between older and younger patients.

Methods And Results: A prospective cohort of 651 PCI patients (26.

Quantification of myocardial blood flow by adenosine-stress CT perfusion imaging in pigs during various degrees of stenosis correlates well with coronary artery blood flow and fractional flow reserve.

Aims: Only few preliminary experimental studies demonstrated the feasibility of adenosine stress CT myocardial perfusion imaging to calculate the absolute myocardial blood flow (MBF), thereby providing information whether a coronary stenosis is flow limiting. Therefore, the aim of our study was to determine whether adenosine stress myocardial perfusion imaging by Dual Source CT (DSCT) enables non-invasive quantification of regional MBF in an animal model with various degrees of coronary flow reduction.

Methods And Results: In seven pigs, a coronary flow probe and an adjustable hydraulic occluder were placed around the left anterior descending coronary artery to monitor the distal coronary artery blood flow (CBF) while several degrees of coronary flow reduction were induced.

Remote ischemic conditioning in percutaneous coronary intervention and coronary artery bypass grafting.

Background: Although remote ischemic conditioning (RIC) by transient limb ischemia in percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) has shown favorable effects on myocardial (ischemia-reperfusion) injury, recent trials provide inconsistent results. The aim of the present study was to assess the effect of RIC in PCI or CABG.

Methods And Results:  Medline/Embase/conference reports were searched for randomized RIC trials and were included if they reported on biomarkers of myocardial injury (CK-MB/troponin T/I), after which, standardized mean differences (SMDs) were calculated (Hedges g statistic).

The ability of high dose rosuvastatin to improve plaque composition in non-intervened coronary arteries: rationale and design of the Integrated Biomarker and Imaging Study-3 (IBIS-3).

Aims: Acute coronary syndromes (ACS) are often caused by rupture of non-flow limiting "vulnerable" atherosclerotic plaque, characterised by a large necrotic core pool and a thin, inflamed fibrous cap that are unidentifiable with diagnostic coronary angiography. The implementation of novel invasive imaging modalities, such as intravascular ultrasound-virtual histology (IVUS-VH) and near-infrared spectroscopy (NIRS), could help identify high-risk patients who are in need of aggressive medical therapy. The intake of high dose rosuvastatin has been shown to reduce plaque containing necrotic core in the carotid arteries, however it remains unknown whether there is a similar effect in the coronary arteries.

Plaque sealing and passivation with a mechanical self-expanding low outward force nitinol vShield device for the treatment of IVUS and OCT-derived thin cap fibroatheromas (TCFAs) in native coronary arteries: report of the pilot study vShield Evaluated at Cardiac hospital in Rotterdam for Investigation and Treatment of TCFA (SECRITT).

Aims: The aim of the pilot SECRITT trial was to evaluate the safety and feasibility of sealing the high risk IVUS and optical coherence tomography-derived thin cap fibroatheroma (TCFA), with a dedicated nitinol self-expanding vShield device.

Methods And Results: After screening with angiography, fractional flow reserve (FFR), intravascular ultrasound virtual histology (IVUS-VH) and optical coherence tomography (OCT), 23 patients met enrolment criteria (presence of non-obstructive VH-derived TCFA lesion with thin cap on OCT) and were randomised to vShield (n=13) versus medical therapy (n=10). In the shielded group, baseline percent diameter stenosis was 33.

Successful stenting of catheter-induced unprotected left main coronary artery dissection.

Catheter-induced left main coronary artery (LMCA) dissection is a dramatic, although uncommon complication of diagnostic coronary angiography and requires prompt treatment. We describe a case of iatrogenic occlusive dissection of the LMCA during coronary angiography, treated by subsequent percutaneous recanalisation.

Thrombotic complication during intracoronary imaging.

Intracoronary imaging with intracoronary ultrasound and coherence tomography is often used in the follow-up of coronary stent implantation. The present case shows an infrequent complication of these procedures, suggesting our continued attention to the selective use of these invasive procedures.

A proinflammatory monocyte response is associated with myocardial injury and impaired functional outcome in patients with ST-segment elevation myocardial infarction: monocytes and myocardial infarction.

Background: In patients with ST-segment elevation myocardial infarction (STEMI), the importance of a well-balanced inflammatory reaction has been recognized for years. Monocytes play essential roles in regulating inflammation. Hence, we investigated the association between inflammatory characteristics of monocytes and myocardial injury and functional outcome in patients with STEMI.

Long-term tissue coverage of a biodegradable polylactide polymer-coated biolimus-eluting stent: comparative sequential assessment with optical coherence tomography until complete resorption of the polymer.

Background: Biolimus-eluting stents (BESs) with a biodegradable polymer in abluminal coating achieve more complete coverage at 9 months compared with sirolimus-eluting stents (SESs) with a durable polymer, as assessed by optical coherence tomography (OCT). Whether this advantage persists or augments after complete resorption of the polymer (>12 months) is unknown.

Methods: The LEADERS trial compared the performance of BES with that of SES.

Coronary microvascular dysfunction in a porcine model of early atherosclerosis and diabetes.

Detailed evaluation of coronary function early in diabetes mellitus (DM)-associated coronary artery disease (CAD) development is difficult in patients. Therefore, we investigated coronary conduit and small artery function in a preatherosclerotic DM porcine model with type 2 characteristics. Streptozotocin-induced DM pigs on a saturated fat/cholesterol (SFC) diet (SFC + DM) were compared with control pigs on SFC and standard (control) diets.

Optical coherence tomography for guidance in bifurcation lesion treatment.

Optical coherence tomography (OCT) has higher resolution than IVUS (approximately 10 times), with the potential to precisely measure lumen diameters in the variable geometry of a bifurcational lesion and to identify superficial lipid laden plaques and calcium, relevant to confirm the severity of the lumen obstruction before treatment and guide location and diameter of the stent. In addition, OCT produces fewer strut-induced artifacts and offers precise evaluation of strut apposition in a real-life clinical setting. The increase in the speed of image acquisition consequent to the introduction of frequency domain OCT allows rapid pull-back at a speed of 2 cm/sec, minimising the amount of contrast required to clear blood during image acquisition, with an average injection of 10-18 ml required for the maximal length currently available of 5.

The Genous™ endothelial progenitor cell capture stent accelerates stent re-endothelialization but does not affect intimal hyperplasia in porcine coronary arteries.

Objectives: To study the effect of endothelial progenitor cell (EPC) capture on the vascular response to coronary stenting.

Background: The introduction of drug-eluting stents has reduced the need for target lesion revascularization, but their effect on delayed healing, inflammation, and vascular dysfunction has emphasized the need to design strategies that improve current DES. One such strategy is to improve endothelialization by capturing CD34-positive cells (EPC) by the stent surface.