Hyun-Hee Choi

The impact of initial and residual thrombus burden on the no-reflow phenomenon in patients with ST-segment elevation myocardial infarction.

BackgroundLimited data are available on the clinical significance of residual thrombi after thrombectomy and prestenting reduced epicardial coronary flow in ST-segment elevation myocardial infarct (STEMI) patients. Materials and methodsThe incidence of the no-reflow phenomenon, defined as a final thrombolysis in myocardial infarction (TIMI) flow grade of up to 2 or a myocardial blush grade of up to 1, was compared in 260 STEMI patients undergoing primary percutaneous coronary intervention according to thrombotic burden. Large thrombotic burden (LTB), defined as a thrombus score of at least 3, was observed in 134 patients, among whom 66 (49.3%) underwent aspiration thrombectomy. No-reflow incidence was compared on the basis of thrombectomy treatment, thrombus residue after thrombectomy, and prestenting TIMI flow grade. ResultsThe no-reflow phenomenon occurred most frequently in LTB patients without thrombectomy, followed by those who underwent thrombectomy and the small thrombus burden group (33.8 vs. 21.2 vs. 10.3%, respectively, P<0.001). Patients with a prestenting residual thrombus or a TIMI flow grade of up to 2 had higher no-reflow incidence than those with no visible prestenting thrombus and a TIMI flow grade of 3 (74 vs. 6.2%, P<0.001). Multiple logistic regression analysis identified a prestenting TIMI flow grade of up to 2 (odds ratio 36.422, 95% confidence interval 13.952–95.079) as an independent predictor of the no-reflow phenomenon. ConclusionManual thrombus aspiration reduced no-reflow incidence in STEMI patients with LTB. However, even after thrombectomy, prestenting residual thrombi and decreased coronary flow were related to a higher occurrence of the no-reflow phenomenon.

Fractional Flow Reserve in Specific Lesion Subsets

Fractional Flow Reserve (FFR) has been also investigated in various conditions of coronary arteries and hearts. The objective of this chapter is to summarize all the relevant literature available about the use of FFR for various coronary lesions and heart condition, especially, in post stent implantation, stent restenosis, myocardial bridge and hypertrophy and post-transplantation.

Prevalence of and factors related to latent tuberculous infection among all employees in a referral hospital

SETTING Referral hospital, South Korea. OBJECTIVE To investigate the prevalence of and factors related to latent tuberculous infection (LTBI) among all hospital employees. DESIGN A cross-sectional study of 479 health care workers (HCWs) undergoing LTBI screening. RESULTS Overall prevalence of LTBI was 15.7%, 43.1% of whom initiated and completed LTBI treatment. Compared with HCWs without LTBI, those with LTBI were more likely to be older (P < 0.001), male (P = 0.003), work in low-risk departments (P = 0.013) and have more years of employment (P < 0.001). LTBI prevalence was highest in physicians (27.8%), followed by HCWs without patient contact (23.4%), nurses (8.3%) and other HCWs in contact with patients (6.9%). In multivariate analysis, compared with HCWs aged <20 years, those aged 40 years were 4.08 times more likely to have LTBI (P = 0.007). In addition, compared with HCWs working for <1 year, those working for 1-5 years or for 5 years were respectively 7.55 (P = 0.014) and 13.69 (P = 0.001) times more likely to have LTBI. CONCLUSIONS Our results suggest that modified LTBI screening strategies, including HCWs with no patient contact and encouraging LTBI treatment participation, might be helpful in improving LTBI control in HCWs.

The effects of the Korean reference value on the prevalence of osteoporosis and the prediction of fracture risk

BackgroundSince the reference value is the core factor of the T-score calculation, it has a significant impact on the prevalence of osteoporosis. The purpose of this study was to determine the effects of using the Korean reference value on the prevalence of osteoporosis and on the prediction of fracture risk.MethodsWe used femoral neck bone mineral density (BMD) data from the Korea National Health and Nutrition Examination Survey (KNHANES) 2008–2011. The Korean reference was identified by the mean and standard deviation of men and women aged 20–29 years. We compared the prevalence and the fracture risk assessment tool (FRAX™) probability obtained from the Korean reference and the NHANES III reference.ResultsIn men, the prevalence of osteoporosis increased when using the Korean men’s reference, and the difference increased up to 9% for those in their 80s. In women, the prevalence increased when using the NHANES III reference, and the difference increased up to 17% for those in their 80s. The reference value also affected the fracture risk probability, and the difference from changing the reference value increased in women and in subjects with more clinical fracture risk factors. In major osteoporotic fractures, the difference of the risk probability was up to 6% in women aged 70–79 years with two clinical risk factors. For femoral neck fractures, the difference was up to 7% in women aged 50–59 years with two clinical risk factors.ConclusionsWe confirmed that the reference value had significant effects on the prevalence of osteoporosis and on the fracture risk probability. The KNHANES 2008–2011 BMD data reflected the characteristics of the Korean BMD status well with regard to data size and study design; therefore, these data can be used as reference values.