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Chronic total occlusion (CTO) remains a challenging lesion subset when considering percutaneous coronary intervention (PCI). Until recently, CTO lesions were associated with relatively low procedural success rates ranging between 60–70% despite evidence of considerable case selection1 ,2 However, the emergence of new techniques and technologies is revolutionising the field, such that procedural success rates in excess of 90% have been described by specialist operators.3 While it has long been appreciated that CTO revascularisation can improve symptoms,4 there is an increasing body of evidence to suggest prognostic benefit may follow.5 In this issue of Heart , Michael et al describe outcomes following CTO PCI among patients with previous coronary artery bypass graft surgery (CABG).6 They demonstrate that prior CABG remains a challenge in CTO PCI, with lower procedural success rates than CTO lesions in previously ungrafted patients. However, the most powerful aspect of their data is that the reporting US centres are consistently achieving high rates of procedural success (85%) despite treating increasingly complex patients. In their cohort 37% of patients had undergone prior CABG, a substantially greater proportion than any other reported registry. This suggests greater patient selection among previous registries, where CTO patients with more complex disease may have been excluded from revascularisation, a situation likely to reflect real world clinical practice. Patients who have symptoms, significant ischaemia, and/or myocardial viability may often be excluded from revascularisation on the basis of feasibility of percutaneous revascularisation —that is, anatomy rather than clinical need. Although chronic occlusions may be present in up to 35% of patients undergoing coronary angiography,7 CTO PCI accounts for only around 5% of all elective PCI procedures.8 Many patients with single vessel de novo CTO are not offered revascularisation at all. Among patients with multivessel disease undergoing PCI, the …

OBJECTIVE: To investigate the potential differential effects of selective endothelin (ET) A and dual ET-A/B receptor blockade in patients with chronic heart failure.METHODS: Nine patients with chronic heart failure (New York Heart Association class II-III) each received intravenous infusions of BQ-123 alone (selective ET-A blockade) and combined BQ-123 and BQ-788 (dual ET-A/B blockade) in a randomised, placebo controlled, three way crossover study.RESULTS: Selective ET-A blockade increased cardiac output (maximum mean (SEM) 33 (12)%, p < 0.001) and reduced mean arterial pressure (maximum -13 (4)%, p < 0.001) and systemic vascular resistance (maximum -26 (8)%, p < 0.001), without changing heart rate (p = 0.38). Dual ET-A/B blockade significantly reduced the changes in all these haemodynamic variables compared with selective ET-A blockade (p < 0.05). Selective ET-A blockade reduced pulmonary artery pressure (maximum 25 (7)%, p = 0.01) and pulmonary vascular resistance (maximum 72 (39)%, p < 0.001). However, there was no difference between these effects and those seen with dual ET-A/B blockade. Unlike selective ET-A blockade, dual ET-A/B blockade increased plasma ET-1 concentrations (by 47 (4)% with low dose and 61 (8)% with high dose, both p < 0.05).CONCLUSIONS: While there appeared to be similar reductions in pulmonary pressures with selective ET-A and dual ET-A/B blockade, selective ET-A blockade caused greater systemic vasodilatation and did not affect ET-1 clearance. In conclusion, there are significant haemodynamic differences between selective ET-A and dual ET-A/B blockade, which may determine responses in individual patients.

Clinical manifestations of coronary atherosclerosis are mainly a consequence of one of the following pathogenesis: The lack of a linear relation between stenosis severity and the probability of developing an ACS is well recognised.3 Indeed the majority of plaques (∼70%) leading to acute myocardial infarction are not of angiographic significance, implying that factors other than stenosis severity determine the probability of vessel closure. The term “vulnerable” plaque defines the vascular substrate most subject to superficial erosion or plaque rupture which may in turn lead to ACS. While there are multiple complex risk and “trigger” factors at work, accurate identification of a “vulnerable” plaque and efficacious treatment to “stabilise” it, thereby reducing the risk of thrombotic induced acute events, would be of major clinical use. In this review we examine stabilisation and passivation of the “vulnerable” plaque by systemic and local drug delivery (LDD). Plaque stabilisation can be defined by any intervention or interaction which, by causing a change in either the structure, content or function of an atherosclerotic plaque and/or the overlying endothelium, will either prevent or reduce the severity of erosion or rupture. Plaque passivation is defined as any intervention that decreases the thrombogenicity of the endoluminal oriented vascular surface. Established risk factors of plaque vulnerability include

AIMS: Stent underexpansion and malapposition are associated with adverse outcomes following percutaneous coronary intervention, but detection and treatment can be challenging in the presence of extensive coronary artery calcification. Frequency domain optical coherence tomography (FD-OCT) is a novel intravascular imaging technique with greater spatial resolution than intravascular ultrasound (IVUS) but its role in the presence of extensive coronary calcification remains unclear. We sought to determine the utility of FD-OCT compared to IVUS imaging to guide percutaneous coronary intervention in patients with severe calcific coronary artery disease.METHODS: 18 matched IVUS and FD-OCT examinations were evaluated following coronary stent implantation in 12 patients (10 male; mean age 70±7 years) undergoing rotational atherectomy for symptomatic calcific coronary artery disease.RESULTS: In-stent luminal areas were smaller (minimum in-stent area 6.77±2.18 vs 7.19±2.62 mm(2), pCONCLUSIONS: Acute stent malapposition occurs frequently in patients with calcific coronary disease undergoing rotational atherectomy and stent implantation. In the presence of extensive coronary artery calcification, FD-OCT affords enhanced stent visualisation and detection of malapposition, facilitating improved postdilation stent apposition and minimal luminal areas.TRIAL REGISTRATION NUMBER: NCT02065102.