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Background: Although disturbed flow is thought to play a central role in the development of advanced coronary atherosclerotic plaques, no causal relationship has been established. We evaluated whether inducing disturbed flow would cause the development of advanced coronary plaques, including thin cap fibroatheroma., Methods and Results: D374Y-PCSK9 hypercholesterolemic minipigs (n=5) were instrumented with an intracoronary shear-modifying stent (SMS). Frequency-domain optical coherence tomography was obtained at baseline, immediately poststent, 19 weeks, and 34 weeks, and used to compute shear stress metrics of disturbed flow. At 34 weeks, plaque type was assessed within serially collected histological sections and coregistered to the distribution of each shear metric. The SMS caused a flow-limiting stenosis, and blood flow exiting the SMS caused regions of increased shear stress on the outer curvature and large regions of low and multidirectional shear stress on the inner curvature of the vessel. As a result, plaque burden was ≈3-fold higher downstream of the SMS than both upstream of the SMS and in the control artery (P<0.001). Advanced plaques were also primarily observed downstream of the SMS, in locations initially exposed to both low (P<0.002) and multidirectional (P<0.002) shear stress. Thin cap fibroatheroma regions demonstrated significantly lower shear stress that persisted over the duration of the study in comparison with other plaque types (P<0.005)., Conclusions: These data support a causal role for lowered and multidirectional shear stress in the initiation of advanced coronary atherosclerotic plaques. Persistently lowered shear stress appears to be the principal flow disturbance needed for the formation of thin cap fibroatheroma., (© 2015 American Heart Association, Inc.)

Background: Obesity alters endocrine and metabolic functions of adipose tissue and has been recognized as a chronic inflammatory disease, which in turn may contribute to the development of insulin resistance, type 2 diabetes, obesity-associated vasculopathy and cardiovascular disease. The pathogenesis of obesity involves many regulatory pathways including transcriptional regulatory networks, including microRNAs., Methods: A total of 83 patients were included in the study. Patients were recruited from a cardiology outpatient clinic and were allocated into 3 age- and sex-matched groups according to their body mass index. Group 1 included 23 morbidly obese, group 2 30 obese, and group 3 30 normal or overweight subjects., Results: In our study, we showed that miR-143 and miR-223 levels were significantly lower in groups 1 and 2 than the control group (normal BMI or overweight)., Conclusions: Obesity leads to alterations in miRNA expressions and miRNA-143 and -223s can be used as biomarkers for the metabolic changes in obesity., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Internal mammary artery (IMA) grafts have been shown to be superior to saphenous vein grafts in terms of rare atherosclerotic involvement, biochemical and physical qualities, and long-term patency rates. The IMA originates from the subclavian artery, just distal to the vertebral artery, and an occlusion or a hemodynamically significant stenosis proximal to the IMA ostium would cause a pressure drop distally and a reversal of flow from the coronary arteries to the IMA in patients with this graft. This condition is referred to as "coronary subclavian steal syndrome" (CSSS). In most cases, the cause of this syndrome is atherosclerotic disease; however, other causes of subclavian artery stenosis (SAS) have the potential to lead to CSSS. Patients with CSSS present with the symptoms of myocardial ischemia due to coronary steal, vertebrobasilar insufficiency, or limb ischemia. Discrepancy in the blood pressure (BP) measurements in two arms should warn the clinician of SAS. A diminished pulse or the bruit of jet flow on the lesion side can be noticed. Doppler ultrasonography, computed tomography angiography, and magnetic resonance angiography are safe and accurate noninvasive modes of diagnosis. Treatment can be surgical or percutaneous.

The optimal management of instent restenosis has yet to be fully clarified. Drug eluting balloons are a popular strategy, but a new stent is preferred when dilatation gives a suboptimal result because of insufficient extrusion of neointimal tissue. There is concern for adding multiple permanent metallic layers to the vessel wall, especially in small vessels. The use of bioabsorbable vascular scaffolds appears an appealing alternative strategy, since it scaffolds the neointimal tissue without further adding metal struts to the vessel wall., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Aim: VCAM-1 and ICAM-1 are two important members of the immunoglobulin gene superfamily of adhesion molecules, and their potential role as biomarkers of diagnosis, severity and prognosis of cardiovascular disease has been investigated in a number of clinical studies. The aim of the present study was to determine the relationship between circulating ICAM-1 and VCAM-1 levels and aortic stiffness in patients referred for echocardiographic examination., Methods: Aortic distensibility was determined by echocardiography using systolic and diastolic aortic diameters in 63 consecutive patients referred for echocardiography. Venous samples were collected in the morning after a 12-hour overnight fast, and serum concentrations of ICAM-1 and VCAM-1 were measured using commercial enzyme immunoassay kits., Results: Data of a total of 63 participants (mean age 55.6 ± 10.5 years, 31 male) were included in the study. Circulating levels of adhesion molecules were VCAM-1: 12.604 ± 3.904 ng/ml and ICAM-1: 45.417 ± 31.429 ng/ml. We were unable to demonstrate any correlation between indices of aortic stiffness and VCAM-1 and ICAM-1 levels., Conclusion: The role of soluble adhesion molecules in cardiovascular disease has not been fully established and clinical studies show inconsistent results. Our results indicate that levels of circulating adhesion molecules cannot be used as markers of aortic stiffness in patients.

Mechanical reperfusion with primary percutaneous coronary intervention in acute ST-segment-elevation myocardial infarction is superior to fibrinolysis in terms of short-term and long-term outcome, provided that it can be delivered on time and by an experienced team. Balloon angioplasty and stent implantation of an occluded epicardial vessel during ST-segment-elevation myocardial infarction can cause disruption of the frail thrombus containing lesions associated with suboptimal myocardial reperfusion and microcirculatory obstruction. Distal embolization of atherothrombotic material can be prevented by thrombus aspiration during primary angioplasty. Mechanical aspiration via end-hole large-lumen thrombectomy catheters has been shown to improve Thrombolysis in Myocardial Infarction (TIMI) flow and result in a more consistent early resolution of ST-segment elevation in multiple registries. More recently, a more sophisticated quantification of the myocardial damage has been applied using myocardial scintigraphy and magnetic resonance, with no difference between patients treated with thrombectomy and patients treated with conventional therapy. The expectations in terms of lasting mortality benefit raised by the first Dutch single-center randomized trial of thrombectomy versus predilation with plain old balloon angioplasty (Thrombus Aspiration During Percutaneous Coronary Intervention in Acute Myocardial Infarction, TAPAS) were not confirmed by a much larger Swedish trial (Thrombus Aspiration ST-Segment Elevation Myocardial Infarction, TASTE) showing no outcome changes. Although we are waiting for new trials to clarify these controversial results, thrombectomy is still used in selected patients with high thrombus load or with persistent occlusion of the infarct-related artery after wire passage. Here we review the various systems available and discuss their relative merits and the reported results.

Objective: The aim of this study is to retrospectively investigate clinical and electrophysiologic characteristics of typical AVNRT with relatively slow tachycardia rates below the average value compared to faster ones, in patients without structural heart disease., Methods: The present study retrospectively included a total of 1,150 patients receiving successful slow-pathway radio frequency ablation for typical slow-fast AVNRT. Patients were divided into two groups according to their tachycardia cycle length: group I included 1,018 patients with tachycardia cycle length < 400 msn and group II included 132 patients with cycle length > 400 msn. Patients with another form of arrhythmia other than typical AVNRT, the existence of structural heart disease, preexisting prolonged PR interval, history of clinically documented AF, and reasons capable of causing AF were accepted as exclusion criterias., Results: The patients in group II were older than those in group 1 (p=0.039), and male ratio was significantly higher in group II compared to group I (p=0.02). Wenckebach cycle length and AV node antegrade effective refractory period values before the RF ablation were significantly higher in group II compared to group I (p=0.0001 and 0.01, respectively). Right atrium effective refractory period values in both pre- and post-ablation period were significantly higher in group I compared to group II (p=0.0001 and 0.004, respectively). The existence of atrial vulnerability before ablation was significantly higher in group II compared to group I (p=0.007); however, there was no difference between the two groups in terms of atrial vulnerability after the ablation. In addition, while the ratio of anterior location as an ablation site near the His-bundle region was significantly higher in group II, the ratio of posterior location was significantly higher in group I (p=0.0001 for both)., Conclusion: Our experience demonstrates that clinical and electrophysiologic characteristics of AVNRT patients with relatively slower tachycardia rates were quite different compared to the faster AVNRT cases.

Radiofrequency (RF) ablation of accessory bypass tracts associated with the Wolff-Parkinson-White (WPW) syndrome has become the treatment of choice for many arrhythmias. Complications are unusual and acute coronary artery occlusion is very rare. We here present a 38-year-old male patient with an acute occlusion of proximal left anterior descending (LAD) coronary artery after RF ablation of a left free wall accessory pathway. An interesting feature is the site of the coronary artery occlusion which is remote from the RF application site. The occlusion was successfully treated with the placement of an intracoronary stent.

The introduction of transcatheter aortic valve implantation (TAVI) has resulted in a paradigm shift in the treatment of patients with severe aortic stenosis. Data from the recent U.S CoreValve Trial suggest, for the first time, that TAVI is associated with a significantly higher rate of survival at one year compared to surgical aortic valve replacement (SAVR) in the treatment of high-risk patients affected by severe aortic stenosis. The present review discusses this study and the current evidence about TAVI, for the treatment of severe aortic stenosis, from major trials and real world registries.

Many drugs are known to cause lengthening of the QT interval. Ibandronic acid is a frequently used agent in the treatment of osteoporosis and is known to cause prolongation of the QT interval due to hypocalcaemia. However, no cases of long QT syndrome associated with ventricular tachycardia (VT) with a serum calcium level within the normal limits have been reported in the literature. We report on a case of a VT-based long QT syndrome associated with the use of ibandronic acid.

Introduction: Cardiovascular system is rich in thyroid hormone receptors and is one of the major sites of action for thyroid hormones. However, the effect of subclinical hypothyroidism (SCH) on atherosclerosis has not been cleared yet., Materials and Methods: SCH is defined as high thyroid-stimulating hormone (TSH) levels in the presence of normal serum T4 and T3 levels. A total of 32 patients with SCH and 29 controls were included in the study. Carotid intima-media thickness, flow-mediated dilatation, and aortic distensibility were compared between the groups., Results: FMD was lower in patients with SCH than in controls. GTN-induced vasodilatation was similar in the patients with SCH and controls. There was no statistically significant difference between the patients with SCH and controls with respect to CIMT and aortic distensibility., Conclusion: SCH is associated with endothelial dysfunction as established by FMD. Inconsistent results of CIMT and aortic stiffness can be explained by these parameters being measures of structural changes whereas FMD is a dynamic measure that reflects the impact of both acute and chronic influences on endothelial function.

Objectives: Although hypertension has been shown to be one of the most important risk factors for atherosclerosis, data about the presence of subclinical atherosclerosis in normotensive offspring with parental history of hypertension are scarce. Accordingly, the current study was designated to evaluate flow-mediated dilatation and aortic stiffness, which are early signs of atherosclerosis in young subjects with parental history of hypertension., Methods: A total of 140 [corrected] healthy, non-obese subjects in the age group of 18-22 years were included in this study and divided into two groups. The first group included 70 offspring of hypertensive parents and the second group included 70 offspring of normotensive parents as controls. In all subjects, endothelium-dependent and endothelium-independent vasodilatation of the brachial artery and aortic elastic parameters were investigated using high-resolution Doppler echocardiography., Results: Offspring of hypertensive parents demonstrated higher values of aortic stiffness (7.1 plus or minus 1.88 and 6.42 plus or minus 1.56, respectively) but lower distensibility (9.47 plus or minus 1.33 and 11.8 plus or minus 3.36 square centimetres per dyne per 106) and flow-mediated dilatation (4.57 plus or minus 1.3 versus 6.34 plus or minus 0.83 percent, p equals 0.0001, respectively) than offspring of hypertensive parents., Conclusion: We observed blunted endothelium-dependent dilatation and aortic stiffness in offspring of hypertensive parents compared with offspring of normotensive [corrected] parents. This is evident in the absence of overt hypertension and other diseases, suggesting that parental history of hypertension is a risk for subclinical atherosclerosis and it may contribute to the progression to hypertension and overt atherosclerosis in later life.

Background: Coronary slow flow (CSF) phenomenon is characterized by delayed opacification of coronary vessels in a normal coronary angiogram. Although clinical and pathological features have been previously described, the underlying pathophysiology has not been fully elucidated. In this study, we aimed to evaluate central aortic pressure, aortic stiffness and left ventricular (LV) function in patients with coronary slow flow., Method and Results: The study population consisted of 154 patients who underwent coronary angiography because of typical and quasi-typical symptoms of angina. 81 patients with angiographically proven CSF and 73 cases with normal coronary flow pattern with similar risk profiles were enrolled in the study. Aortic pressures and indexes of elastic properties were evaluated using invasive methods. Aortic pulse pressure (mm Hg) and pulsality index of patients with CSF were found to be significantly higher than those of controls (60.8 ± 13.8 vs. 53.7 ± 14.5, p = 0.002; 0.84 ± 0.22 vs. 0.67 ± 0.18, p = 0.0001, respectively). LV Doppler parameters were deteriorated in patients with CSF. Aortic fractional pulse pressure and pulsality index were significantly correlated with the mean TIMI frame count and LV diastolic parameters in correlation analysis., Conclusion: The present findings allow us to conclude that impaired aortic elasticity in patients with CSF may also be responsible for the impaired LV diastolic parameters., (Copyright © 2010 S. Karger AG, Basel.)

Background: Glycosylated hemoglobin (HbA1c) level on admission is a prognostic factor for mortality in patients with and without diabetes after myocardial infarction. In the present study, the authors examined the relationship between admission HbA1c level and myocardial perfusion abnormalities in patients with acute myocardial infarction., Methods: One hundred consecutive patients with acute myocardial infarction who were treated with thrombolytic therapy were included in the present prospective study. Blood glucose and HbA1c levels of all patients were measured within 3 h of admission. Patients were divided into three groups according to HbA1c level: 4.5% to 6.4% (n=25), 6.5% to 8.5% (n=28) and higher than 8.5% (n=47). All patients then underwent exercise thallium-201 imaging and coronary angiography to determine ischemic scores and the number of diseased coronary arteries four weeks after admission., Results: Seven patients died within the four-week follow-up period. There was a significant relationship between admission HbA1c level and mortality (P=0.009). Furthermore, there was a significant relationship between HbA1c level and total ischemic scores in patients with acute myocardial infarction (r=0.482; P=0.001). Ischemic scores increased as HbA1c levels increased in patients with acute myocardial infarction., Conclusions: The results demonstrated that admission plasma glucose and HbA1c levels are prognostic factors associated with mortality after acute myocardial infarction.