Urban rail systems: analysis of the factors behind success

Investment in urban rail systems has increased rapidly over the past decades. While there have been some successful systems, a significant number have failed to be as successful as expected in improving public transport and urban environment. These experiences have led to a considerable debate in the literature about the effectiveness of new urban rail systems and whether it is worthwhile investing in them. While these debates continue, political support for metros, and particularly light rail systems, is still strong, and investment in them is very likely to continue. Hence, it is extremely important to understand the factors that make these systems successful. The paper presents the findings of a research aimed at identifying these factors based on the analysis of eight new urban rail systems: four in the USA, three in the UK and one in Canada. The paper presents the results of the performance analysis of the case studies as well as a detailed analysis of the factors that affected the performance of each system. Based on the case study analysis, a comprehensive list of factors that make urban rail systems successful is presented. The analysis also facilitates a comparison between the experiences of the three countries, and focuses on the effects of different operating environments and different planning approaches on the performance of urban rail systems. The paper concludes with a comparison of the findings of this research to those of previous studies

Rescue coronary stenting with heparin-coated Jostents for failed thrombolysis in acute myocardial infarction

The aim of the present study was to assess the procedural safety and in-hospital and long-term effectiveness of heparin-coated Jostents after failed thrombolysis in acute myocardial infarction. We prospectively analyzed the acute and long-term clinical and angiographic outcornes of 35 consecutive patients treated with heparin-coated Jostents for thrombolytic failure. Rescue coronary stenting was successful in 34 of 35 patients (97%). Thrombolysis in Myocardial Infarction flow grade 3 was obtained in 31 patients (88.5%). The only patient with procedural failure died from cardiogenic shock a day after the procedure. One patient (2.8%) underwent an emergency coronary bypass operation because of angiographic evidence of stent thrombosis with re-infarction. During in-hospital follow-up, 2 patients (5.7%) underwent an elective coronary bypass operation after successful stent implantation of the infarct-related artery because of existing severe multivessel coronary artery disease. Minor bleeding complications at the vascular access site occurred in 3 (8.6%) patients. No cerebrovascular or any other major bleeding complication occurred. One patient (2.1%) underwent repeat coronary angioplasty for restenosis and an elective coronary artery bypass operation was performed in one patient (2.8%) during the 294 +/- 150 days follow-up. The rate of target vessel revascularization was 14.3% and the event-free survival rate was 80%. Twenty-six patients (90%) had angiographic follow-up at six months, and stent restenosis was found in 5 (19.2%). This study demonstrates that heparin-coated Jostents are safe, with low in-hospital and long-term mortality fates for the treatment of failed thrombolysis in acute myocardial infarction. The angiographic restenosis and target vessel revascularization rates of this registry are also acceptable

Thrombolysis with streptokinase during cardiopulmonary resuscitation: A single center experience and review of the literature

Objective: To report our experience with use of thrombolysis with streptokinase during cardiopulmonary resuscitation of patients with cardiac arrest due to myocardial infarction

Mid-to-long-term patency comparison of the right internal thoracic artery grafts on the left anterior descending and on the right coronary arteries

Background: The excellent results obtained from internal thoracic artery for myocardial revascularization have led surgeons to simultaneous use of other arterial conduits, particularly the right internal thoracic artery. However, some controversy still exists regarding the optimal target coronary artery for this graft; different strategies have been proposed for bilateral internal thoracic artery grafting. Patients and Methods: 59 patients with right internal thoracic artery grafts were monitored using coronary arteriography in order to compare the patency of this graft on the left anterior descending and the right coronary arteries. The right internal thoracic artery was grafted to left anterior descending artery in 39 patients (group 1) and to right coronary artery in 20 patients (group 2). Results: The mean period of follow-up was 64.07 months (range: 37 to 185 months). Overall, 8 of the 59 grafts (13.6%) were occluded at the arteriography. In group 1, 1 of 39 (2.6%) grafts and in group 2, 7 of 20 (35%) grafts are found to be occluded. These results are considered statistically significant (p<0.001). Comment: The results show that the patency of the right internal thoracic artery is significantly better on the left anterior descending artery than on the right coronary artery in the mid-to-long term, and patency does not differ from the left internal thoracic artery on the left anterior descending artery

Fracture of popliteal artery stents

In peripheral arterial obstructive disease, more than 50% of all lesions are localized in the femoropopliteal segment and surgical revascularization is the treatment of choice. Percutaneous transluminal angioplasty (PTA) is recommended for short lesions, with subsequent stent implantation if the result is sub-optimal or dissections occur after PTA or for restenosis. There are both acute and late complications with stent implantation. In the present patient, stents were placed in the left popliteal artery where the left knee joint flexes, and obstruction because of stent fracture occurred 6 months later. The patient eventually underwent left femoro-popliteal saphenous vein bypass grafting

?-3 fatty acid treatment in cardiac syndrome X: A double-blind, randomized, placebo-controlled clinical study

OBJECTIVE: We conducted a clinical trial to examine the effect of ?-3 fatty acids in patients with cardiac syndrome X (CSX). We aimed to evaluate the potential impact of ?-3 fatty acids on endothelial function, oxidative stress, and symptom relief in the CSX. METHODS AND RESULTS: Eighteen patients with CSX were enrolled according to a double-blind, randomized, placebo-controlled design. Patients were randomized to ?-3 fatty acids (1440 mg/day, n=8) or placebo (n=10) for 4 months. We assessed plasma levels of malondialdehyde (MDA), endothelium-dependent vasodilatation [flow-mediated dilatation (FMD)], endothelium-independent vasodilatation [nitroglycerin- mediated dilatation (NMD)], and status of symptom [score with Seattle Angina Questionnaire (SAQ)] before and after the treatment. After 4 months, patients who were treated with ?-3 fatty acids showed significant increases in the FMD (from 47±48 to 104±23%, P<0.05) and NMD (from 51±53 to 93±35%, P<0.05) values, and significant decreases in the plasma MDA levels (4.4±0.86 to 3.35±0.33 µmol/l, P=0.012). SAQ scores were increased significantly in both groups (from 60±14 to 73±15%, P<0.05 placebo, from 67±10 to 81±9%, P<0.05 treatment group). NMD was correlated negatively with the plasma MDA levels. CONCLUSION: Four months of therapy with a moderate dose of ?-3 fatty acids improved the endothelial function and reduced oxidative stress in patients with CSX. © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins

Revascularization of chronic coronary artery occlusions using laser debulking followed by stent implantation

Objective - Chronic total occlusions are considered unfavourable for percutaneous balloon angio-. plasty because of the low rate of success and the high rate of restenosis. Stent implantation after recanalization of chronic total occlusions has been shown to reduce restenosis and reocclusion rates compared with balloon angioplasty in recently published randomized trials. However, it is not well known whether laser debulking before stent implantation would improve the benefit of stenting in chronic total occlusions