2014 ESC/EACTS Guidelines on myocardial revascularization: The Task Force on Myocardial Revascularization of the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS)Developed with the special contribution of the European Association of Percutaneous Cardiovascular Interventions (EAPCI)

Treatment of in-stent restenosis with bioresorbable vascular scaffolds: optical coherence tomography insights

The role of the bioresorbable vascular scaffold (BVS) in patients with in-stent restenosis (ISR) remains unsettled. We present optical coherence tomography (OCT) findings in a series of 15 consecutive patients undergoing treatment of ISR with a BVS under systematic OCT guidance. OCT disclosed severe ISR in all patients (minimal lumen area [MLA], 1.3 ± 0.6 mm(2); stent obstruction 80% ± 10%). After the procedure, OCT MLA was 6.4 ± 2 mm(2) with a final BVS expansion of 79% ± 19%. "Angiographically silent" edge dissections (n = 6), intradevice dissections (n = 3), tissue prolapse (n = 3), and malapposition (n = 3) were also readily visualized. These findings underscore the diagnostic value of OCT in patients undergoing BVS implantation for ISR.

Adjunctive manual thrombus aspiration during ST-segment elevation myocardial infarction: a meta-analysis of randomized controlled trials

OBJECTIVE

The aim of this study was to synthesize evidence by examining the effects of manual thrombus aspiration on clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI).

METHODS AND RESULTS

A total of 26 randomized controlled trials (RCTs), enrolling 11,780 patients, with 5,869 patients randomized to manual thrombus aspiration and 5,911 patients randomized to conventional percutaneous coronary intervention (PCI), were included in the meta-analysis. Separate clinical outcome analyses were based on different follow-up periods. There were no statistically reductions in the incidences of mortality (risk ratio [RR], 0.86 [95% confidence interval [CI]: 0.73 to 1.02]), reinfarction (RR, 0.62 [CI, 0.31 to 1.32]) or target vessel revascularization (RR, 0.89 [CI, 0.75 to 1.05]) in the manual thrombus aspiration arm at 12 to 24 months of follow-up. The composite major adverse cardiac events (MACEs) outcomes were significantly lower in the manual thrombus aspiration arm over the long-term follow-up (RR, 0.76 [CI, 0.63 to 0.91]). A lower incidence of reinfarction was observed in the hospital to 30 days (RR, 0.59 [CI, 0.37 to 0.92]).

CONCLUSION

The present meta-analysis suggested that there was no evidence that using manual thrombus aspiration in patients with STEMI could provide distinct benefits in long-term clinical outcomes.

Anticoagulant therapy during primary percutaneous coronary intervention for acute myocardial infarction: a meta-analysis of randomized trials in the era of stents and P2Y12 inhibitors

OBJECTIVES

To investigate the relative benefits of unfractionated heparin, low molecular weight heparin(LMWH), fondaparinux, and bivalirudin as treatment options for patients with ST segment elevation myocardial infarction undergoing percutaneous coronary intervention (PCI).

DESIGN

Mixed treatment comparison and direct comparison meta-analysis of randomized trials in the era of stents and P2Y12 inhibitors.

DATA SOURCES AND STUDY SELECTION

A search of Medline, Embase, Cochrane Central Register of Controlled Trials (CENTRAL) for randomized trials comparing unfractionated heparin plus glycoprotein IIb/IIIa inhibitor(GpIIb/IIIa inhibitor), unfractionated heparin, bivalirudin, fondaparinux, or LMWH plus GpIIb/IIIa inhibitor for patients undergoing primary PCI.

OUTCOMES

The primary efficacy outcome was short term (in hospital or within 30 days) major adverse cardiovascular event; the primary safety outcome was short term major bleeding.

RESULTS

We identified 22 randomized trials that enrolled 22,434 patients. In the mixed treatment comparison models, when compared with unfractionated heparin plus GpIIb/IIIa inhibitor, unfractionated heparin was associated with a higher risk of major adverse cardiovascular events (relative risk 1.49 (95% confidence interval 1.21 to 1.84), as were bivalirudin (relative risk 1.34 (1.01 to 1.78)) and fondaparinux (1.78 (1.01 to 3.14)). LMWH plus GpIIb/IIIa inhibitor showed highest treatment efficacy, followed (in order) by unfractionated heparin plus GpIIb/IIIa inhibitor, bivalirudin, unfractionated heparin, and fondaparinux. Bivalirudin was associated with lower major bleeding risk compared with unfractionated heparin plus GpIIb/IIIa inhibitor (relative risk 0.47 (0.30 to 0.74)) or unfractionated heparin (0.58 (0.37 to 0.90)). Bivalirudin, followed by unfractionated heparin, LMWH plus GpIIb/IIIa inhibitor, unfractionated heparin plus GpIIb/IIIa inhibitor, and fondaparinux were the hierarchy for treatment safety. Results were similar in direct comparison meta-analyses: bivalirudin was associated with a 39%, 44%, and 65% higher risk of myocardial infarction, urgent revascularization, and stent thrombosis respectively when compared with unfractionated heparin with or without GpIIb/IIIa inhibitor. However, bivalirudin was associated with a 48% lower risk of major bleeding compared with unfractionated heparin plus GpIIb/IIIa inhibitor and 32% lower compared with unfractionated heparin alone.

CONCLUSIONS

In patients undergoing primary PCI, unfractionated heparin plus GpIIb/IIIa inhibitor and LMWH plus GpIIb/IIIa inhibitor were most efficacious, with the lowest rate of major adverse cardiovascular events, whereas bivalirudin was safest, with the lowest bleeding. These relationships should be considered in selecting anticoagulant therapies in patients undergoing primary PCI.

[Antithrombocytic therapy and PCI. Duration of therapy after DCB/stents/scaffolds]

The duration of dual antiplatelet therapy (DAPT) after percutaneous coronary interventions (PCI) depends on the type of intervention and the clinical situation of the patient. After angioplasty alone (plain old balloon angioplasty, POBA) DAPT is not yet established but does, however, make sense to continue for 4 weeks. The duration of DAPT after placement of bare metal stents (BMS) is 4 weeks, after drug-eluting stents (DES) 6 months, after bioresorbable vascular scaffold (BVS) systems 6-12 months and after drug-coated balloon catheters (DCB) without a new implant 4 weeks.

[Antiplatelet therapy in acute coronary syndrome. Prehospital phase: nothing, aspirin or what?]

In most cases of ST segment elevation myocardial infarction (STEMI) a major coronary vessel is occluded by a thrombus. This is why early and effective antiplatelet therapy plays a key role. The current guidelines recommend the administration of dual antiplatelet therapy as early as possible. Despite the lack of convincing clinical evidence, prehospital administration appears reasonable, primarily because of pharmacokinetic considerations. Ticagrelor should be preferentially administered because the largest amount of evidence is available and it appears to be safe. In high-risk patients undergoing transfer to a catheterization laboratory, upstream use of a glycoprotein (GP) IIb/IIIa receptor antagonist (tirofiban) may be considered. Acute coronary syndrome without ST segment elevation (NSTE-ACS) represents a clinically heterogeneous group. Current guidelines recommend that antiplatelet therapy should be initiated as early as possible when the diagnosis of NSTE-ACS is made. If there is high clinical suspicion of NSTE-ACS acetylsalicylic acid (ASA) should be given before hospital admission. In high-risk patients prehospital administration of ticagrelor may be considered.

The optimal management of patients on oral anticoagulation undergoing coronary artery stenting. The 10th Anniversary Overview

Even 10 years after the first appearance in the literature of articles reporting on the management of patients on oral anticoagulation (OAC) undergoing percutaneous coronary intervention with stent (PCI-S), this issue is still controversial. Nonetheless, some guidance for the everyday management of this patient subset, accounting for about 5-8 % of all patients referred for PCI-S, has been developed. In general, a period of triple therapy (TT) of OAC, with either vitamin K-antagonists (VKA) or non-vitamin K-antagonist oral anticoagulants (NOAC), aspirin, and clopidogrel is warranted, followed by the combination of OAC, and a single antiplatelet agent for up to 12 months, and then OAC alone. The duration of the initial period of TT is dependent on the individual risk of thromboembolism, and bleeding, as well as the clinical context in which PCI-S is performed (elective vs acute coronary syndrome), and the type of stent implanted (bare-metal vs drug-eluting). In this article, we aim to provide a comprehensive, at-a-glance, overview of the management strategies, which are currently suggested for the peri-procedural, medium-term, and long-term periods following PCI-S in OAC patients. While acknowledging that most of the evidence has been obtained from patients on OAC because of atrial fibrillation, and with warfarin being the most frequently used VKA, we refer in this overview to the whole population of OAC patients undergoing PCI-S. We refer to the whole population of patients on OAC undergoing PCI-S also when OAC is carried out with NOAC rather than VKA, pointing out, when appropriate, the particular management issues.

Familial hypobetalipoproteinemia: genetics and metabolism

Familial hypobetalipoproteinemia (FHBL), an autosomal dominant disorder, is defined as <5th percentile LDL-cholesterol or apolipoprotein (apo) B in the plasma. FHBL subjects are generally heterozygous and asymptomatic. Three genetic forms exist: (i) premature stop codon specifying mutations of APOB; (ii) FHBL linked to a susceptibility locus on the chromosome 3p21; and (iii) FHBL linked neither to APOB nor to the chromosome 3p21. In heterozygous apoB-defective FHBL, the hepatic VLDL export system is defective because apoB 100, the product of the normal allele, is produced at approximately 25% of normal rate, and truncated apoB is cleared too rapidly. The reduced capacity for hepatic triglyceride export increases hepatic fat three-fold. Indexes of adiposity and insulin action are similar to controls. 'Knock-in' mouse models of apoB truncations resemble human FHBL phenotypes. Liver fat in the chromosome 3p21-linked FHBL is normal. Elucidation of the genetic basis of the non-apoB FHBL could uncover attractive targets for lipid-lowering therapy. (See note added in proof.).

Alpha-crystallin: an ATP-independent complete molecular chaperone toward sorbitol dehydrogenase

alpha-Crystallin, the major component of the vertebrate lens, is known to interact with proteins undergoing denaturation and to protect them from aggregation phenomena. Bovine lens sorbitol dehydrogenase (SDH) was previously shown to be completely protected by alpha-crystallin from thermally induced aggregation and inactivation. Here we report that alpha-crystallin, in the presence of the SDH pyridine cofactor NAD(H), can exert a remarkable chaperone action by favoring the recovery of the enzyme activity from chemically denaturated SDH up to 77%. Indeed, even in the absence of the cofactor, alpha-crystallin present at a ratio with SDH of 20:1 (w:w) allows a recovery of 35% of the enzyme activity. The effect of ATP in enhancing alpha-crystallin-promoted SDH renaturation appears to be both nonspecific and to not involve hydrolysis phenomena, thus confirming that the chaperone action of alpha-crystallin is not dependent on ATP as energy donor.

Biomimetic actuators: where technology and cell biology merge

The structural and functional analysis of biological macromolecules has reached a level of resolution that allows mechanistic interpretations of molecular action, giving rise to the view of enzymes as molecular machines. This machine analogy is not merely metaphorical, as bio-analogous molecular machines actually are being used as motors in the fields of nanotechnology and robotics. As the borderline between molecular cell biology and technology blurs, developments in the engineering and material sciences become increasingly instructive sources of models and concepts for biologists. In this review, we provide a--necessarily selective--summary of recent progress in the usage of biological and biomimetic materials as actuators in artificial environments, focussing on motors built from DNA, classical cellular motor systems (tubulin/kinesin, actin/myosin), the rotary motor F1F0-ATPase and protein-based 'smart' materials.

Interaction of volkensin with HeLa cells: binding, uptake, intracellular localization, degradation and exocytosis

Among two-chain ribosome-inactivating proteins (RIPs), volkensin is the most toxic to cells and animals, and is retrogradely axonally transported in the rat central nervous system, being an effective suicide transport agent. Here we studied the binding, endocytosis, intracellular routeing, degradation and exocytosis of this RIP. The interaction of volkensin with HeLa cells was compared to that of nigrin b, as an example of a type 2 RIP with low toxicity, and of ricin, as a reference toxin. Nigrin b and volkensin bound to cells with comparable affinity (approx. 10(-10) M) and had a similar number of binding sites (2 x 10(5)/cell), two-log lower than that reported for ricin. The cellular uptake of volkensin was lower than that reported for nigrin b and ricin. Confocal microscopy showed the rapid localization of volkensin in the Golgi stacks with a perinuclear localization similar to that of ricin, while nigrin b was distributed between cytoplasmic dots and the Golgi compartment. Consistently, brefeldin A, which disrupts the Golgi apparatus, protected cells from the inhibition of protein synthesis by volkensin or ricin, whereas it was ineffective in the case of nigrin b. Of the cell-released RIPs, 57% of volkensin and only 5% of ricin were active, whilst exocytosed nigrin b was totally inactive. Despite the low binding to, and uptake by, cells, the high cytotoxicity of volkensin may depend on (i) routeing to the Golgi apparatus, (ii) the low level of degradation, (iii) rapid recycling and (iv) the high percentage of active toxin remaining after exocytosis.