Complications of chronic total occlusion percutaneous coronary intervention.

Chronic total occlusion percutaneous coronary interventions can be highly complex and are associated with an increased risk of complications, such as perforation, acute vessel closure (which can lead to rapid haemodynamic compromise if it involves the donor vessel), and equipment loss or entrapment. Awareness of the potential complications and meticulous attention to equipment position and patient monitoring can help minimise the risk of complications and allow prompt treatment should they occur.

Fragmentation processes in two-phase materials.

We investigate the fragmentation process of solid materials with crystalline and amorphous phases using the the discrete element method. Damage initiates inside spherical samples above the contact zone in a region where the circumferential stress field is tensile. Cracks initiated in this region grow to form meridional planes. If the collision energy exceeds a critical value which depends on the material's internal structure, cracks reach the sample surface resulting in fragmentation. We show that this primary fragmentation mechanism is very robust with respect to the internal structure of the material. For all configurations, a sharp transition from the damage to the fragmentation regime is observed, with smaller critical collision energies for crystalline samples. The mass distribution of the fragments follows a power law for small fragments with an exponent that is characteristic for the branching merging process of unstable cracks. Moreover this exponent depends only on the dimensionally of the system and not on the microstructure.

Estimating the treatment cascade of chronic hepatitis B and C in Greece using a telephone survey.

Accurate diagnosis and treatment rates for chronic hepatitis B (HBV) and C virus (HCV) infections are usually missing. Aim of this study was to estimate the HBV and HCV treatment cascade (proportion and absolute numbers of tested, aware/unaware, infected and treated) in Greek adults. A telephone survey was conducted in a sample representative of the Greek adult general population. Prevalence rates were age-standardized for the Greek adult population and corrected for high-risk individuals not included in the survey. Of the 9974 participants, 5255 (52.7%) had been tested for HBV and 2062 (20.7%) for HCV with the proportion varying according to age and being higher in middle-age groups (P < 0.001). HBsAg was reported positive in 111/5255 (2.11%) and anti-HCV in 26/2062 (1.26%) tested cases. The age-adjusted prevalence was estimated to be 2.39% for HBV and 1.79% for HCV. Taking into account individuals at high risk for viral hepatitis not included in the survey, the 'true' prevalence was estimated to be 2.58% for HBV and 1.87% for HCV. Anti-HBV and anti-HCV treatment had been taken by 36/111 (32.4%) chronic HBV and 15/26 (57.7%) chronic HCV patients. In conclusion, almost 50% of chronic HBV and 80% of chronic HCV patients in Greece may be unaware of their infection, while only 32% or 58% of diagnosed chronic HBV or HCV patients, respectively, have been ever treated. Therefore, intensive efforts are required to improve the efficacy of screening for HBV and particularly for HCV as well as to reduce the barriers to treatment among diagnosed patients.

Air trapping in Wegener's granulomatosis: an additional finding on expiratory chest HRCT.

PURPOSE: This study was undertaken to assess the presence and extent of air trapping (AT) on high-resolution computed tomography (HRCT) in patients with Wegener's granulomatosis (WG) and to correlate the finding with the inspiratory pattern and bronchial/bronchiolar involvement. MATERIALS AND METHODS: Twenty-one patients (7 M/14 F) with WG underwent inspiratory and expiratory HRCT. Images were evaluated for the presence and extent of AT and for airway involvement (bronchi/bronchioles); the predominant HRCT pattern was also documented. The attenuation difference was measured between the areas of AT on expiration and the same areas on inspiration in order to verify the finding of AT. The extent of AT was calculated by visual scoring and correlated with the predominant inspiratory patterns and bronchial/bronchiolar involvement. RESULTS: AT was found in seven patients (33.3%) and its extent ranged between 3% and 70% (mean 15.8±7). Two patients showed no lesions on inspiratory HRCT, and the only finding was AT on expiration. The attenuation difference between areas of AT on expiration and the same areas on inspiration ranged between 32 and 89 HU. Inspiratory HRCT was pathological in 19 patients (90.4%), and the principal lung patterns were nodular, cavitary or noncavitary (n=7, 38.9%); ground-glass opacities (n=5, 26.3%); masses (n=3, 15.8%); fibrotic (n=3, 15.8%); and consolidation with air bronchogram (n=1, 5.3%). Bronchial and bronchiolar involvement was found in 14 and five patients, respectively. No statistically significant correlation was found between AT extent and the findings on inspiration. In addition, there were no specific patterns that caused higher or lower scores of AT. Moreover, when bronchial or bronchiolar involvement was absent, the mean AT score was statistically significantly higher. CONCLUSIONS: Areas of AT represent a new and indirect HRCT finding--and in rare cases the only finding--of pulmonary WG. The nonsignificant correlation between AT extent and inspiratory findings may suggest AT as an additional HRCT finding in patients with WG.

Public perceptions in relation to intention to receive pandemic influenza vaccination in a random population sample: evidence from a cross-sectional telephone survey.

A cross-sectional telephone survey on a nationally representative sample of 1,000 Greek households was performed to assess the acceptability of the pandemic influenza A(H1N1)v vaccine, factors associated with intention to decline and stated reasons for declining vaccination. The survey was initiated the last week of August 2009 (week 35) and is still ongoing (analysis up to week 44). The percentage of participants answering they would probably not/definitely not accept the vaccine increased from 47.1% in week 35 to 63.1% in week 44 (test for trend: p<0.001). More than half of the people which chronic illnesses (53.3%) indicated probably not/definitely not. Factors associated with intention to decline vaccination were female sex, age between 30-64 years, perception of low likelihood of getting infected or of low risk associated with influenza, and absence of household members suffering from chronic illnesses. For the majority of the respondents (59.8%), the main reason for intending to decline vaccination was the belief that the vaccine might not be safe. Promotion of vaccination programmes should be designed taking into account the attitudinal barriers to the pandemic vaccine.