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This study investigated the sexual differences of coronary artery disease (CAD) prevalence and its association with cardiovascular risk factors in the asymptomatic population.In total 6434 asymptomatic participants without known CAD (1740 women and 4694 men) underwent coronary computed tomography angiography (CCTA). The prevalence of significant CAD (diameter stenosis ≥50%) and other CCTA findings were compared by sex, and its influence on CAD was investigated in groups stratified by the number of cardiovascular risk factors, including age (55 years), hypertension, diabetes, dyslipidemia, and current smoking.The prevalence of current smokers, hypertension, and diabetes were higher in men than women. The mean coronary artery calcium score was 13.1 ± 58.4 for women and 51.1 ± 158.2 for men; the coronary atherosclerosis burden indices were significantly higher in men than women. Significant CAD was identified in 65 women (3.7%) and 429 men (9.1%), showing a significant association (adjusted odds ratio [OR] 2.38, P 0.001). The relatively higher risk for significant CAD in men was observed in patients with fewer risk factors, and the risk difference was not significant in patients with many risk factors (adjusted ORs: 7.69, 3.37, 1.71, 1.31, and 0.88 in patients with 0, 1, 2, 3, and 4-5 risk factors, respectively). The association between sex and risk factor groups was significant (P 0.001).In the asymptomatic population, a significantly higher CAD prevalence was noted in men than women. However, women with a high number of cardiovascular risk factors showed a CAD prevalence similar to that of men.

OBJECTIVES We aimed to assess the advantages of using the retrograde approach as an initial strategy rather than as a rescue strategy for complex chronic total occlusions (CTOs). BACKGROUND Even for complex CTOs where a retrograde approach is deemed necessary, an antegrade approach is frequently used as an initial strategy in real-world practice. METHODS We evaluated 352 retrograde procedures for CTO conducted at our high-volume center between January 2007 and January 2019. Procedural efficiency and safety was assessed based on the guidewire manipulation time (GWMT) and the occurrence of procedure-related adverse events for the primary retrograde approach (PRA) and the rescue retrograde approach (RRA). RESULTS PRA and RRA were used in 191 (54.3%) and 161 (45.7%) of the CTO procedures, respectively. The complexity of the CTO lesion was significantly higher in the PRA group than in the RRA group (Japanese-CTO score, 2.62 ± 1.07 vs. 2.38 ± 1.06, p = 0.037). The technical success rate of two groups was similar (p = 0.47). The median GWMT required for PRA was significantly shorter than that for RRA (85 [interquartile range, 55-126] vs. 120 [85-157] min, p

BACKGROUND Even though several mobile applications that can measure blood pressure (BP) have been developed, the data about the accuracy of those applications are limited. OBJECTIVE This study assessed the accuracy of AlwaysBP (test) in BP measurement compared with the standard cuff-based manual method of brachial BP measurement (reference). AlwaysBP is a smartphone software that estimates systolic BP (SBP) and diastolic BP (DBP) based on the pulse transit time (PTT). The PTT was calculated from the finger photoplethysmogram using the camera and from seismocardiogram using the inertial measurement unit sensor of a commercially available smartphone. METHODS A total of 87 participants without known cardiovascular disease were enrolled in the study. The primary analysis aimed to evaluate the accuracy of the test method compared with the reference method in the entire study population. The secondary analysis was performed to confirm the stability of the test method for up to 4 weeks in 15 subjects. At enrollment, the gender, arm circumference, and BP distribution were considered according to the current guidelines. RESULTS Among the study subjects, 45 (51.7%) individuals were male and the average age was 35.6 ± 10.4 years. Hypertension was diagnosed in 14 subjects (16.1%) prior to the study. The mean test and reference SBP were 120.0 ± 18.8 and 118.7 ± 20.2 mmHg, respectively, and the difference was 1.2 ± 7.1 mmHg (r = 0.935, P < 0.001). The mean test and reference DBP were 80.1 ± 12.6 and 81.1 ± 14.4 mmHg, respectively, and the difference was −1.0 ± 6.0 mmHg (r = 0.911, P < 0.001). At the 4-week time point, the differences between SBP and DBP were 0.1 ± 8.8 and −2.4 ± 7.6 mmHg. CONCLUSIONS The AlwaysBP software exhibited acceptable accuracy regarding SBP and DBP measurement compared with the standard BP measurement method. This technology can be easily applied in everyday life and may improve the general population’s awareness of hypertension, thus helping to control it. CLINICALTRIAL none

BACKGROUND: Few studies have evaluated intravascular ultrasound (IVUS) use in chronic total occlusion (CTO) percutaneous coronary intervention (PCI). AIMS: In CTO-PCI, we aimed to (1) evaluate the clinical benefits of performing post-stent IVUS in preventing adverse clinical events, and (2) identify IVUS parameters and cut-off values for prediction of target lesion revascularisation (TLR)/reocclusion. METHODS: A total of 1,077 patients with 1,077 CTO lesions treated with drug-eluting stents (DES) were included. Clinical outcomes during a median follow-up of 6.3 years were compared between subjects with and those without post-stent IVUS using the inverse probability weighting method. RESULTS: Of 1,077 patients, post-stent IVUS was performed in 838 (77.8%) cases while in the remaining 239 (22.2%) cases it was not. In the weighted population, the risk of TLR/reocclusion was significantly lower in subjects with post-stent IVUS (9.6% vs 18.9%, hazard ratio [HR] 0.54, 95% confidence interval [CI]: 0.34-0.86, p=0.01), compared with those without post-stent IVUS. Cox regression analysis showed that minimal stent area (MSA) measured by IVUS was the only parameter independently associated with TLR/reocclusion (HR 0.78, 95% CI: 0.64-0.95; p=0.01) and the optimal MSA cut-off value was 4.9 mm2 for prediction of TLR/reocclusion (area under the curve=0.632, p=0.001). CONCLUSIONS: In CTO-PCI with DES, post-stent IVUS evaluation was associated with a lower risk of TLR/reocclusion. The final MSA was independently associated with TLR/reocclusion with a cut-off value of 4.9 mm(2).

Objectives This study evaluated the association between elevated levels of lipoprotein(a) [Lp(a)] and risk of recurrent ischemic events in patients who underwent percutaneous coronary intervention (PCI). Background Elevated levels of Lp(a) have been identified as an independent, possibly causal, risk factor for atherosclerotic cardiovascular disease in a general population study. Methods A prospective single-center registry was used to identify 12,064 patients with baseline Lp(a) measurements who underwent PCI between 2003 and 2013. The primary outcomes were a composite of cardiovascular death, spontaneous myocardial infarction, and ischemic stroke. Results From the registry, 3,747 (31.1%) patients had high Lp(a) (>30 mg/dL) and 8,317 (68.9%) patients had low Lp(a) (≤30 mg/dL). During a median follow-up of 7.4 years, primary outcomes occurred in 1,490 patients, and the incidence rates of primary outcomes were 2.0 per 100 person-years in the high-Lp(a) group and 1.6 per 100 person-years in the low-Lp(a) group (adjusted hazard ratio [aHR]: 1.17; 95% confidence interval [CI]: 1.05-1.30; P = 0.004). Increased risk of recurrent ischemic cardiovascular events in the high-Lp(a) group was consistent in various subgroups including patients receiving statin treatment at discharge (aHR: 1.18; 95% CI: 1.03-1.34; P = 0.011). In addition, the risk of repeated revascularization was significantly higher in the high-Lp(a) group (aHR: 1.13; 95% CI: 1.02-1.25; P = 0.022). Conclusions Elevated levels of Lp(a) were significantly associated with the recurrent ischemic events in patients who underwent PCI. This study provides a rationale for outcome trials to test Lp(a)-lowering therapy for secondary prevention in patients undergoing PCI.

BackgroundThis study assessed the accuracy of AlwaysBP (test) in blood pressure (BP) measurement compared with the standard cuff-based manual method of brachial BP measurement (reference). AlwaysBP is a smartphone software that estimates systolic BP (SBP) and diastolic BP (DBP) based on the pulse transit time (PTT). The PTT was calculated from the finger photoplethysmogram using the camera and from seismocardiogram using the inertial measurement unit sensor of a commercially available smartphone.MethodsA total of 87 participants without known cardiovascular disease were enrolled in the study. The primary analysis aimed to evaluate the accuracy of the test method compared with the reference method in the entire study population. The secondary analysis was performed to confirm the stability of the test method for up to 4 weeks in 15 subjects. At enrollment, the gender, arm circumference, and BP distribution were considered according to the current guidelines.ResultsAmong the study subjects, 45 (51.7%) individuals were male and the average age was 35.6 ± 10.4 years. Hypertension was diagnosed in 14 subjects (16.1%) prior to the study. The mean test and reference SBP were 120.0 ± 18.8 and 118.7 ± 20.2 mmHg, respectively, and the difference was 1.2 ± 7.1 mmHg (r = 0.935, P < 0.001). The mean test and reference DBP were 80.1 ± 12.6 and 81.1 ± 14.4 mmHg, respectively, and the difference was −1.0 ± 6.0 mmHg (r = 0.911, P < 0.001). At the 4-week time point, the differences between SBP and DBP were 0.1 ± 8.8 and −2.4 ± 7.6 mmHg.ConclusionsThe AlwaysBP software exhibited acceptable accuracy regarding SBP and DBP measurement compared with the standard BP measurement method. This technology can be easily applied in everyday life and may improve the general population’s awareness of hypertension, thus helping to control it.

This study sought to determine hospital variation in the use of follow-up stress testing (FUST) and invasive coronary angiography (FUCAG) after percutaneous coronary intervention (PCI). The claims records of 150,580 Korean patients who received PCI in 128 hospitals between 2008 and 2015 were analyzed. Patient were considered to have undergone FUST and FUCAG, when these testings were performed within two years after discharge from the index hospitalization. Hierarchical generalized linear and frailty models were used to evaluate binary and time-to-event outcomes. Hospital-level risk-standardized FUCAG and FUST rates were highly variable across the hospitals (median, 0.41; interquartile range [IQR], 0.27–0.59; median, 0.22; IQR, 0.08–0.39, respectively). The performances of various models predicting the likelihood of FUCAG and FUST were compared, and the best performance was observed with the models adjusted for patient case mix and individual hospital effects as random effects (receiver operating characteristic curves, 0.72 for FUCAG; 0.82 for FUST). The intraclass correlation coefficients of the models (0.41 and 0.68, respectively) indicated that a considerable proportion of the observed variation was related to individual institutional effects. Higher hospital-level FUCAG and FUST rates were not preventive of death or myocardial infarction. Increased repeat revascularizations were observed in hospitals with higher FUCAG rates.

This paper reports on the unprecedented 4 W power microelectromechanical systems (MEMS) relay with a contact- force-maximizing structure in a dual-contact material system. A MEMS relay with dual (hard and soft) contact materials is known to have high durability in hot-switching conditions, and the contact force is also considered to be the most important factor that contributes to an efficient reduction of the contact resistance. We devised a contact-force-maximizing structure with a plate-type suspended structure and in-plate springs and applied it to a dual-contact material system to achieve extremely low contact resistance. The fabricated MEMS relay successfully operated sequential switching between the dual contact materials in the contact-force-maximizing structure and thereby showed an extremely low contact resistance of 1.65 $\text{m}\Omega $ with a switching time of $7 {\mu \text {s}}$ at an operating voltage of 80 V. Thanks to the contact-force-maximizing structure with the dual-contact material system, the fabricated MEMS relay achieved a lifetime of up to $1.3\times 10^{\mathbf {3}}$ cycles in the hot-switching conditions of 4 W (10 V/400 mA) in an air atmosphere with a negligible variation of the contact resistance. This power level is the highest reported to date. [2020-0223]

Aims The aim of this study was to compare percutaneous coronary intervention (PCI) outcomes in relation to stent optimisation profiles between in-stent chronic total occlusions (CTOs) and de novo CTOs. Methods and results We evaluated 1,516 consecutive patients who underwent PCI for 147 in-stent CTOs (9.3%) and 1,439 de novo CTOs between 2007 and 2018. The primary endpoint was target vessel failure (TVF) consisting of a composite of cardiac death, target vessel-related myocardial infarction, or target vessel revascularisation. The final post-stenting intravascular ultrasound (IVUS) images were analysed. Target lesion complexity reflected by the Japanese CTO score was similar, albeit calcification was more prevalent in de novo CTOs, whereas occlusion length >20 mm was more frequent in in-stent CTOs. The technical success (88.4% vs 87.5%, p=0.84) and in-hospital adverse event (1.4% vs 3.6%, p=0.26) rates were similar between CTO types. Among those who received drug-eluting stents, the five-year TVF (11.0% vs 10.7%, p=0.99) and target vessel revascularisation (4.2% vs 3.7%, p=0.81) rates were similar between groups. Total stent length, minimum stent area (5.4±1.8 vs 5.5±1.8 mm2, p=0.77), and maximal plaque burden of the reference segments were largely comparable between groups. Conclusions In-stent CTO PCI with drug-eluting stents optimised by IVUS guidance offers as acceptable long-term clinical results as those achieved in de novo CTOs.

Background Although the need to detect restenosis has diminished in the contemporary practice of percutaneous coronary intervention (PCI) with drug-eluting stents (DES), the surveillance of ischemia owing to restenosis or disease progression deserves attention in high-risk PCI settings. It is unknown whether follow-up strategy of routine noninvasive functional testing potentially reduces the risk of major cardiovascular events in high-risk PCI patients. Methods The POST-PCI study is an investigator-initiated, multicenter, prospective randomized trial comparing the effectiveness of two follow-up strategies in patients with high-risk anatomic or clinical characteristics who underwent PCI. Study participants were randomly assigned to either (1) the routine noninvasive stress testing (exercise electrocardiography, nuclear stress imaging, or stress echocardiography) at 12 months post-PCI or (2) the standard-care without routine testing. In the routine stress testing group, depending on the testing results, all clinical decisions regarding subsequent diagnostic or therapeutic procedures were at the treating physician's discretion. The primary endpoint was a composite outcome of death from any causes, myocardial infarction, or hospitalization for unstable angina at 2 years post-PCI. Results More than 1700 high-risk PCI patients have been randomized over 2.0 years at 11 major cardiac centers in Korea. Conclusion This pragmatic POST-PCI trial will provide valuable clinical evidence on the effectiveness of follow-up strategy of routine noninvasive stress testing in high-risk PCI patients.

BACKGROUND AND OBJECTIVES Nonalcoholic fatty liver disease (NAFLD) is an excessive accumulation of fat into the liver as a result of increased inflammation and insulin resistance. Although there can be common pathogenic mechanisms for NAFLD and hypertension associated with the development of cardiovascular diseases, little data are showing the association between NAFLD and hypertension in a large-scale cohort study. Thus, we evaluated the ability of the fatty liver index (FLI), a surrogate marker of NAFLD, to predict the development of hypertension in healthy individuals. METHODS We included 334,280 healthy individuals without known comorbidities who underwent the National Health check-ups in South Korea from 2009 to 2014. The association between the FLI and hypertension was analyzed using multivariate Cox proportional-hazards models. RESULTS During a median of 5.2 years' follow-up, 24,678 subjects (7.4%) had new-onset hypertension. We categorized total subjects into quartile groups according to FLI (range: Q1, 0-4.9; Q2, 5.0-12.5; Q3, 12.6-31.0; and Q4, >31.0). The incidence of hypertension was higher in subjects with the highest FLI than in those with the lowest FLI (Q4, 9,968 [11.9%] vs. Q1, 2,277 [2.7%]; p

Objectives The aim of this study was to investigate the long-term impact of SYNTAX (Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) score (SS) on differential outcomes after percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) for left main coronary artery (LMCA) disease. Background The very long term prognostic effect of SS on mortality and major cardiovascular events after LMCA revascularization is still undetermined. Methods In the MAIN-COMPARE (Ten-Year Outcomes of Stents Versus Coronary-Artery Bypass Grafting for Left Main Coronary Artery Disease) registry, patients with baseline SS measurements were analyzed. The 10-year rates of all-cause mortality, the composite of death, Q-wave myocardial infarction, or stroke, and target vessel revascularization after PCI or CABG were compared according to baseline SS. Results Among 1,580 patients with baseline SS, 547 patients (34.6%) had low SS (≤22), 350 (22.2%) had intermediate SS (23 to 32), and 683 (43.2%) had high SS (≥33). In patients with low to intermediate SS, the adjusted 10-year risks for death and serious composite outcome were similar between the PCI group and the CABG group. However, in patients with high SS, PCI with stenting, compared with CABG, was associated with a higher risk for death (hazard ratio: 1.39; 95% confidence interval: 1.00 to 1.92; p = 0.048) and serious composite outcome (hazard ratio: 1.27; 95% confidence interval: 0.94 to 1.74; p = 0.123). In each revascularization group, conventional tertiles of SS had a differential prognostic impact on 10-year clinical outcomes in the PCI arm but not in the CABG arm. Conclusions In this 10-year extended follow-up of patients undergoing LMCA revascularization, CABG showed a clear prognostic benefit over PCI in patients with high anatomic complexity measured by SS at baseline. The discriminative capacity of SS on long-term outcomes was relevant in the PCI group but not in the CABG group. (Ten-Year Outcomes of Stents Versus Coronary-Artery Bypass Grafting for Left Main Coronary Artery Disease [MAIN-COMPARE]; NCT02791412)

Atherectomy as a pretreatment has the potential to improve the outcomes of drug-coated balloon (DCB) treatment by reducing and modifying atherosclerotic plaques. The present study investigated the outcomes of atherectomy plus DCB (A+DCB) compared with DCB alone for the treatment of femoropopliteal artery disease.A total of 311 patients (348 limbs) underwent endovascular therapy using DCB for native femoropopliteal artery lesions at two endovascular centers. Of these, 82 limbs were treated with A+DCB and 266 limbs with DCB alone. After propensity score matching based on clinical and lesion characteristics, a total of 82 pairs was compared for immediate and mid-term outcomes.For the matched study groups, the lesion length was 172.7±111.2 mm, and severe calcification was observed in 43.3%. The technical success rate was higher in the A+DCB group than in the DCB group (80.5% vs. 62.2%, p=0.015). However, the A+DCB group showed more procedure-related minor complications (37.0% vs. 13.4%, p=0.047). At 2-year follow-up, primary clinical patency (73.8% vs. 82.6%, p=0.158) and the target lesion revascularization (TLR)-free survival (84.3% vs. 88.2%, p=0.261) did not differ between the two groups. In Cox proportional hazard analysis, atherectomy showed no significant impact on the outcome of DCB treatments.The pretreatment with atherectomy improved technical success of DCB treatment; however, it was associated with increased minor complications. In this study, A+DCB showed no clinical benefit in terms of TLR-free survival or clinical patency compared with DCB treatment alone.

Age and sex contribute to determining coronary revascularization strategies for patients with left main coronary artery (LMCA) disease. We examined age- and sex-related differences in comparative outcomes after percutaneous coronary intervention (PCI) or coronary-artery bypass grafting (CABG) for LMCA disease. A total of 4,001 patients with LMCA disease (men, n = 3,100, women, n = 901) who underwent PCI (n = 2,615) or CABG (n = 1,386) from the Interventional Research Incorporation Society-Left MAIN Revascularization registry were analyzed. Patients were stratified into subgroups according to the tertiles of age (60 years, 60 to 69 years, and ≥70 years) and sex. The primary outcome was the composite of death from any cause, myocardial infarction, or stroke. During the median 6.3 years of follow-up, the adjusted risks for primary outcome after PCI relative to CABG were similar in patients aged60 years (hazard ratio [HR]: 0.64, 95% confidence interval [CI]: 0.35 to 1.16), 60 to 69 years (HR: 1.21; 95% CI: 0.82 to 1.80), and ≥70 years (HR: 0.90; 95% CI: 0.66 to 1.22) with no significant age-related interactions (P

The aims of the study were to identify the differences of forces in the hip adductors between with or without the abduction bar and to evaluate the effect of hip compression bandage on the spasticity of the adductor muscles.Thirty-three patients with cerebral palsy (Gross Motor Functional Classification System IV and V) were prospectively included. Surface electromyography was taken by attaching electromyography on the adductor and abductor muscles. Theraband was used as hip compression bandage. Surface electromyography were taken when spasticity provoked with and without abduction bar, as well as with both abduction bar and hip compression bandage. Root mean square values were measured.Root mean square values were significantly increased with abduction bar in the adductor longus, adductor magnus, and tensor fascia lata muscles. Adductor Sum and Net Adduction Index showed significant increases after the use of abduction bar. After applying hip compression bandage, the Net Adduction Index was significantly decreased.Our results showed significant changes in the adductor muscles' amplitude, Adduction Sum, and Net Adduction Index. These results indicate that forces that worsen hip dislocation may develop, and therefore, abduction bar should either not be used for spastic cerebral palsy patients or should only be used with hip compression wrapping in place as well.

BACKGROUND Little is known about how the relative treatment effect of percutaneous coronary intervention (PCI) and coronary-artery bypass grafting (CABG) on clinical outcomes in ostial or shaft left main coronary artery (LMCA) disease has evolved over time. METHODS This study included 2,112 patients with ostial or shaft LMCA disease from IRIS-MAIN registry who underwent PCI (n = 1,329) or CABG (n = 783). Patients were stratified by time period based on stent type availability: wave 1 (1995-2002, bare-metal stent [BMS] era); wave 2 (2003-2006, first-generation drug-eluting stent [DES] era); and wave 3 (2007-2014, second-generation DES era). RESULTS Compared to CABG, PCI has been used more frequently from wave 1 to wave 3. PCI showed substantial improvements over time with respect to death (P for trend = 0.012); the composite of death, myocardial infarction (MI), or stroke (P for trend = 0.047); repeat revascularization (P for trend

Probing micro-bumps for pre-bond testing is an essential process to check for a known good die. In recent technologies, micro-bumps such those used in 3-D-IC are too small and dense, which gives the probing a new challenge. Moreover, developers are concerned that the tip ends of the micro-bumps are mechanically damaged during the pre-bond testing, which is detrimental for the post-process IC assembly. Thus, many low damage probing solutions have been developed, but they still inevitably damage the tip end of the micro-bumps when the conventional probing method, vertical contact, is used. In this paper, for the first time, we demonstrate lateral contact probing on 55- $\mu \text{m}$ pitch micro-bumps without any damage to the tip ends. We successfully realized the testing with monolithically fabricated probes by nickel electroplating with a high aspect ratio photoresist mold. The measured fatigue life of the fabricated probes was at least100 000 cycles. Furthermore, the measured current carrying capacity was more than 180 mA. Proving our concept, the contact test results on the micro-bumps showed no damage to the tip end, and the contact resistance was below 1.13 $ {\Omega }$ . Finally, the10 000 probes achieved a uniform 55- $\mu \text{m}$ pitch, which ensured the possibility in real testing. [2018-0041]

An innovative plastic deformation method is proposed to tune metal-based MEMS devices after fabrication. The plastic deformation is a well-known failure mechanism in MEMS devices, which includes a phenomenon that the devices do not return original position after repeated actuation. Here, in contrast to this common experience, we exploit the plastic deformation for the first time to tune the performance of MEMS devices, by producing deliberate, controlled plastic deformation with the help of Joule heating. The proposed plastic deformation method is precisely and predictably controlled by the model we developed here, and it was successfully demonstrated and evaluated using a fabricated MEMS device. Unlike conventional plastic deformation methods, the proposed method was accomplished solely by electrical control, which means that the method can be employed in integrated devices. Tuning resolution was demonstrated at a 10-nm level, which is remarkably smaller than that of conventional plastic deformation methods, where the tuning resolution is typically several micrometers. We confirmed that the proposed method does not deteriorate the basic performance of the fabricated MEMS devices. Finally, we proposed and demonstrated a method for calibrating MEMS devices after fabrication and suggested an interesting application, which is recovering the performance of aged MEMS devices. [2017-0129]

OBJECTIVES Previous epidemiological studies have limitations in revealing whether cardiovascular disease (CVD) incidence is mediated by interim occurrence of other metabolic diseases in otherwise healthy nonalcoholic fatty liver disease (NAFLD) patients. METHODS The study population consisted of 334 280 healthy subjects who had had the National Health check-ups in South Korea from 2009 to 2014. The fatty liver index (FLI) was used to identify subjects with NAFLD. CVD was defined as occurrence of a composite of cardiovascular death, myocardial infarction, ischemic stroke, or coronary revascularization. The association between FLI and CVD incidence was analyzed using time-dependent Cox regression analyses. RESULTS The study population was categorized into quartile groups according to FLI (range: Q1, 0-4.9; Q2, 5.0-12.5; Q3, 12.6-31.0; Q4, >31.0). The median follow-up duration was 5.4 years, during which subjects with higher FLIs experienced CVD more frequently than did those with lower FLIs [Q1, 215 (0.3%); Q2, 498 (0.6%); Q3, 753 (0.9%); Q4, 981 (1.2%); P

BACKGROUND This study sought to assess the relationship between stage 1 hypertension and subclinical coronary atherosclerosis. METHODS A total of 4,666 individuals with available coronary computed tomography angiography (CCTA) results from a health checkup were enrolled. The classification of hypertension was adapted from the American College of Cardiology/American Heart Association (ACC/AHA) 2017 guideline. The presence of coronary plaques and its characteristics, and other CCTA findings were assessed. RESULTS There was a linear relationship between blood pressure (BP), both systolic BP (SBP) and diastolic BP (DBP), and the presence of coronary plaque. Patients were classified into 4 groups according to the BP category: normal BP (SBP 50% was not statistically significant. Isolated diastolic and isolated systolic stage 1 hypertensions were significantly related to the presence of coronary plaque. The elevated BP group was not associated with any positive CCTA findings. CONCLUSIONS Stage 1 hypertension was independently associated with subclinical coronary atherosclerosis.

There is limited data regarding the association between sarcopenia and clinical outcomes in patients who underwent transcatheter aortic valve implantation (TAVI). From the prospective ASAN-TAVI registry, we evaluated a total of 522 patients with severe aortic stenosis who underwent TAVI between March 2010 and November 2018. Routine pre-TAVI computed tomography scan was used to calculate the skeletal muscle index (SMI), which was defined as skeletal muscle area at the L3 level divided by height squared; subject patients were classified into the gender-specific tertile groups of SMI. The patients' mean age was 79 years and 49% were men. Mean SMI values were 41.3 ± 6.7 cm2/m2 in men and 34.1 ± 6.5 cm2/m2 in women. The Kaplan-Meier estimates of all-cause mortality at 12 months were higher in the low-tertile group than in the mid- and high-tertile groups (15.5%, 7.1%, and 6.2%, respectively; p = 0.036). In multivariate analysis, low-tertile of SMI was an independent predictor of mortality (vs high-tertile of SMI, hazard ratio 2.69; 95% confidence interval, 1.18 to 6.12; p = 0.019). The all-cause mortality was substantially higher in the groups with high-surgical risk plus low SMI tertile. The risk assessment with addition of SMI on conventional STS-PROM score was significantly improved by statistical measures of model reclassification and discrimination. In patients who underwent TAVI, sarcopenia measured by SMI was significantly associated with an increased risk of 1-year mortality. The prognostic impact of SMI-measured sarcopenia was more prominent in patients with high surgical risks.

Background Compared with conventional bifemoral (BF) approach, radial plus ipsilateral femoral (RF) approach may be feasible in the percutaneous intervention for iliac artery chronic total occlusion (CTO). Materials/Methods We included patients underwent iliac CTO intervention between August 2009 to July 2018 in a tertiary referral center in Korea. Results A total of 83 patients were enrolled in this study. Of them, 51 and 32 patients were categorized into RF and BF initial access groups, respectively. The overall success rates were 98.0% and 96.7% in RF and BF group, and techniques were also similar including use of bilateral wiring, stent type and profile, and post balloon but longer procedure time in BF group. Additional contralateral femoral access was needed in 6 patients for the treatment of contralateral lesions, distal embolization, and due to tortuous right subclavian artery. Periprocedural complications including vascular injury, iliac perforation, distal embolization occurred similarly in both groups with numerically lower rate of periprocedural bleeding in the RF group (9.8%) compared to BF group (21.9%). Clinical follow-up at 6 months showed there were no difference in the rates of death, cardiovascular death, target-limb reintervention, and unplanned target limb amputation in both groups Conclusions RF approach for iliac CTO intervention was related to similar technical success rate with acceptable periprocedural safety outcomes compared to conventional BF approach.

Background Data are still limited regarding whether there are differential long‐term outcomes after percutaneous coronary intervention versus coronary artery bypass grafting ( CABG ) for left main coronary artery disease with or without diabetes mellitus ( DM ). Methods and Results Using the 10‐year data from the MAIN ‐ COMPARE (Revascularization for Unprotected Left Main Coronary Artery Stenosis: Comparison of Percutaneous Coronary Angioplasty Versus Surgical Revascularization) registry, we sought to examine the effect of DM on comparative outcomes after percutaneous coronary intervention or CABG in patients with unprotected left main coronary artery disease. The outcomes of interest were all‐cause mortality; a composite of death, Q‐wave myocardial infarction, or stroke; and target‐vessel revascularization. The primary adjusted analyses were performed with the use of propensity scores and inverse‐probability weighting. Of 2240 patients with left main coronary artery revascularization, 722 (32%) had DM . In the overall population, the adjusted 10‐year risks of death and composite outcome were similar between percutaneous coronary intervention and CABG , irrespective of DM status ( P interaction : 0.41, mortality; 0.40, composite outcome). However, in the cohort of bare‐metal stents and concurrent CABG , we observed differential outcomes after stenting and CABG by DM status ( P interaction : 0.09, mortality; 0.04, composite outcome), favoring CABG in patients with DM. In the cohort of drug‐eluting stents and concurrent CABG , the better effect of CABG over stenting was narrowed in patients with DM without a significant interaction ( P interaction : 0.63, mortality; 0.47, composite outcome). Conclusions In this cohort of patients with longest follow‐up who underwent left main coronary artery revascularization, the clinical impact of DM favoring CABG over percutaneous coronary intervention has diminished over time from the bare‐metal stent to the drug‐eluting stent era. Registration URL : http://www.clini​caltr​ials.gov . Unique identifier: NCT 02791412.

Background Heart failure (HF) is relatively common cardiovascular disease with high mortality and morbidity. Although it is associated with many cardiovascular risk factors, the association between nonalcoholic fatty liver disease (NAFLD), the most common chronic liver disease, and HF has not been evaluated in a large-scale cohort study. Thus, we evaluated the ability of the fatty liver Index (FLI), a surrogate marker of NAFLD, to predict the development of HF in healthy individuals. Methods We analyzed the association between the FLI and new-onset HF with multivariate Cox proportional-hazards models in 308,578 healthy persons without comorbidities who underwent the National Health check-ups in the republic of Korea from 2009 to 2014. Results A total of 2532 subjects (0.8%) were newly diagnosed with HF during the study period (a median of 5.4 years). We categorized our subjects into quartile groups according to FLI (Q1, 0–4.9; Q2, 5.0–12.5; Q3, 12.6–31.0; and Q4, > 31.0). The cumulative incidence of HF was significantly higher in the highest FLI group than in the lowest FLI group (Q1, 307 [0.4%] and Q4, 890 [1.2%]; P Conclusions Higher FLI was independently associated with increased risk of HF in a healthy Korean population.

This paper reports an unprecedented 4 W MEMS relay that utilizes a dual contact-material system and a contact force maximizing structure. The contact force-maximizing structure is designed to achieve extremely low contact resistance. So far, commercialized MEMS relays have achieved a power level of 0.03 W in hot-switching conditions. In this work, we achieved a MEMS relay with operation reliability up to $5.7\times 10^{4}$ cycles and $1.3\times 10^{3}$ cycles at 10 V/300 mA (3 W) and 10 V/400 mA (4 W) signals, respectively, in hot-switching conditions. This achievement was due to an extremely-low contact resistance of $1.65\ \mathrm{m}\Omega$ achieved by utilizing the proposed contact force maximizing structure coupled with dual contact materials.

Studies evaluating the nature of ischemic burden of chronic total occlusion (CTO) vessels are still lacking.A total of 165 patients with single vessel CTO2.5 mm in an epicardial coronary artery who underwent single photon emission computed tomography (SPECT) were enrolled in the study. Ischemic burden was calculated with the use of semi-quantitative SPECT analysis, and was defined as the summed difference score (SDS) divided by the maximal limit of the score (=SDS/68).The mean age of the participants was 59.5 years and the CTO of the left anterior descending coronary artery (LAD), left circumplex coronary artery (LCX), and right coronary artery (RCA) accounted for 93 (56.4%), 18 (10.9%), and 54 (32.7%) patients, respectively. The median ischemic burden of the total population was 8.8%, and it was highest in the LAD CTO (10.3%) compared with the LCX (5.9%) and RCA CTO (5.9%, p0.001). High-ischemic burden (ischemic burden10%) was observed in 66 patients (40.0%), and in 47 patients (50.5%) of the LAD CTO. Ischemic burden was different according to the CTO location only in LAD CTO. The statistically significant predictors for high-ischemic burden were hypertension, baseline ejection fraction45%, LAD CTO, proximal CTO location, and de novo CTO. Japanese-CTO score and Rentrop scale collateral grade were not associated with high-ischemic burden.Only 40% of patients with single vessel CTO had ischemic burden10%. For CTO vessels, measurement of ischemic burden using SPECT prior to revascularization may be helpful in identifying beneficial subjects.

The prognostic value of left atrial (LA) function in terms of long-term clinical outcomes after mitral regurgitation (MR) surgery remains unclear. Therefore, we investigated the impact of preoperative LA global longitudinal strain (LAGLS) on the long-term postoperative clinical outcomes in chronic severe MR patients who underwent mitral valve (MV) repair surgery.From January 2012 to December 2017, we analyzed 338 patients (mean age, 51.9±12.5 years; 218 males [64.5%]) treated with MV repair surgery for severe MR. The primary outcome was cardiovascular events, defined as the composite of all-cause death, newly developed atrial fibrillation (AF), and re-hospitalization for cardiovascular causes.During a median follow-up of 45 months (interquartile range, 26-65), 30 (8.9%) cardiovascular events, 5 (1.5%) all-cause death, 8 (2.4%) newly developed AF, and 26 (7.7%) re-hospitalizations occurred. On multivariable analysis, baseline LAGLS was an independent predictor of cardiovascular events (adjusted hazard ratio [HR], 0.91; 95% confidential interval [CI], 0.85-0.97; p=0.004) and re-hospitalization (adjusted HR, 0.93; 95% CI, 0.86-1.00; p=0.037). According to the optimal cutoff value of LAGLS, patients with low LAGLS (23.6%) had a significantly higher risk of cardiovascular events (adjusted HR, 2.70; 95% CI, 1.04-7.00; p=0.041) than those with high LAGLS (≥23.6%). In a subgroup analysis, patients with high LAGLS had better clinical outcomes regardless of whether the patient had a LA volume index60 mL/m².In patients with chronic severe MR who received successful MV repair surgery, preoperative LAGLS is an independent predictor of long-term postoperative outcomes.

Structured Abstract Background Percutaneous coronary intervention (PCI) for true ostial left anterior descending artery (LAD)-chronic total occlusion (CTO) lesions poses technical challenges owing to its inherent anatomical features. Methods In total, 270 consecutive patients who underwent PCI for ostial LAD-CTO at 13 major cardiac centers in South Korea were included. Ostial LAD-CTO was strictly defined as a LAD-CTO lesion the proximal cap of which was confined within 1 mm from the carina of the distal left main coronary artery (LMCA) bifurcation. Results Ostial LAD-CTOs were frequently accompanied by stumpless lesion entry (43.4%), whereas significant bending within the occluded segment was less frequent (14.4%). The overall technical success rate was 85.9%, and serious in-hospital adverse events occurred in 5.6%. The retrograde approach tended to contribute more frequently to success in patients with concomitant LMCA disease, stumpless CTO, interventional collaterals, and higher Japanese-CTO scores. Apparent dissection or hematoma requiring rescue procedure at the LMCA or left circumflex artery occurred in 14 patients (5.2%), with a higher tendency in patients who had LMCA disease (12.1% vs. 4.2%) and stumpless entry (9.4% vs. 2.0%) than in those without. Among patients who were successfully treated with an average number of 1.7 stents, target-vessel failure occurred in 23 patients (9.9%) during a median 3.3 years of follow-up. Conclusions In this first, large-scale analysis of true ostial LAD-CTO, PCI was feasible with a high technical success rate and favorable mid-term outcomes. Clinically relevant inflow vessel injury can occur during PCI and should be an important technical consideration regarding safety.

A 4-terminal microelectromechanical systems (MEMS) relay has long been sought for signal switching applications because it allows de-coupling of the actuation (body and gate) and signal (source and drain) components unlike a 3-terminal MEMS relay. However, the contact resistance still remains a serious problem in current 4-terminal MEMS relays compared with the 3-terminal MEMS relays. In this paper, using theoretical analysis, we first determined that the two-contact design, which was the most common design in the 4-terminal MEMS relay, was the origin of the high contact resistance. We subsequently developed a 4-terminal MEMS relay with a novel single-contact design. The fabricated 4-terminal MEMS relay with the single-contact design exhibited a contact resistance of 18 $\text{m}\Omega $ . To the best of our knowledge, this result is the lowest value among 4-terminal MEMS relays. In addition, we demonstrated that the two-contacts are the origin of the high contact resistance using measurement. The relay operated up to $1.1\times 10^{6}$ cycles at 1 V / 50 mA in air and hot switching conditions. Finally, the proposed 4-terminal MEMS relay was hermetically packaged for use in commercial applications. [2017-0183]

A nanoparticle has been reported as a promising lubricant to increase the durability of microelectromechanical systems (MEMS) switches, but there remains much room for development and scientific observations. In this paper, we present the fabrication and research platform for a nanoparticle lubricated MEMS switch; we measured its characteristics and investigated the mechanisms behind it. In the measurements, gold nanoparticle lubrication demonstrated an increased average adhesion force from 16.38 to 23.68 $\mu \text{N}$ by 44.51% and a decreased average electrical contact resistance from 211.20 to 49.85 $\text{m}\Omega $ by 76.40%. In a hot switching mode lifetime test, the gold nanoparticle lubricated MEMS switch exhibited extension of reliability from $5.13\times 10^{4}$ to $4.75\times 10^{5}$ cycles, which corresponds to 9.26-fold increase. We attribute this remarkable enhancement to a mechanical stress release via lateral deformation of the nanoparticle and refreshment of the contact spots owing to movement of nanoparticles. [2017-0127]

BACKGROUND & AIMS Previous studies demonstrated conflicting results regarding the association between non-alcoholic fatty liver disease (NAFLD) and atrial fibrillation (AF). The statistical power was not sufficient because of modest sample sizes of these studies. We analysed a large population-based cohort to evaluate the association between NAFLD and AF. METHODS We evaluated 334 280 healthy individuals without comorbidities who underwent National Health check-ups in South Korea from 2009 to 2014. NAFLD was defined by a surrogate marker, the fatty liver index (FLI). The association between FLI and AF incidence was analysed using multivariate Cox proportional hazards regression models. RESULTS During a median follow-up of 5.3 years, 1415 subjects (0.4%) were newly diagnosed with AF. Subjects were categorized into quartile groups according to FLI (range: Q1, 0-4.9; Q2, 5.0-12.5; Q3, 12.6-31.0; Q4, >31.0). The cumulative incidence of AF was significantly higher in subjects with higher FLIs than in those with lower FLIs (Q1, 167 [0.2%]; Q2, 281 [0.3%]; Q3, 470 [0.6%]; Q4, 497 [0.6%]; P

Background Acuity of clinical presentation may influence decision-making of percutaneous coronary intervention (PCI) and coronary-artery bypass grafting (CABG) for left main coronary artery (LMCA) disease. However, it is undetermined whether clinical indication for myocardial revascularization may affect the relative long-term effect after PCI and CABG. Methods In the MAIN-COMPARE study including 2240 patients with LMCA disease treated with PCI (n = 1102) or CABG (n = 1138), we examined interaction between acuity of clinical presentation (acute coronary syndromes [ACS] or non-ACS) and revascularization strategy on 10-year outcomes. Primary outcome was a composite of all-cause death, Q-wave myocardial infarction (MI), or stroke. Secondary outcomes were all-cause death or target-vessel revascularization (TVR). Results In overall patients, 1,603 patients (71.6%) presented with ACS and 637 patients (28.4%) presented with non-ACS. The 10-year adjusted risks for primary composite outcome were similar after PCI and CABG among patients presented with non-ACS (hazard ratio [HR] 1.07; 95% confidence interval [CI] 0.71–1.61) and those presented with ACS (HR 1.00; 95% CI 0.81–1.24) (P-for-interaction=0.29). The adjusted risks of death were also similar between 2 groups in non-ACS (HR 0.98; 95% CI 0.63–1.51) and ACS (HR 1.02; 95% CI 0.81–1.28) patients (P-for-interaction=0.62). The adjusted risks of TVR were consistently higher after PCI in in non-ACS (HR 6.38; 95% CI 3.14–12.96) and ACS (HR 3.96; 95% CI 2.80–5.60) patients (P-for-interaction=0.39). Conclusions In patients with LMCA disease, we have identified no significant interaction between the acuity of clinical indication and the relative treatment effect of PCI versus CABG on 10-year clinical outcomes.

This paper reports a highly reliable electrostatic microelectromechanical systems (MEMS) relay for high-power switching applications. The main proposal to elevate reliability is to reduce thermal damage in the contact area. Since a contact resistance is the key parameter determining the amount of Joule-heating and the corresponding thermal damage, we devised a unique spring structure to maximize the contact force (resulting in a low contact resistance) using a reasonable actuation voltage named a two-step spring system. Another important feature was applied to alleviate Joule-heating, which is to use an insulator having high thermal conductivity to dissipate the generated heat efficiently, named a heat sink insulator. The fabricated MEMS relay exhibited 2 $\text{m}\Omega $ in contact resistance, which is the lowest level reported so far with an actuation voltage of 45 V. Reliability was remarkably enhanced over ten times by the heat sink insulator. Consequently, by applying these two approaches simultaneously, the fabricated MEMS relay was successfully operated up to the $5.3 \times 10^{6}$ cycles at 1 V/200 mA in ambient air and hot switching condition, which is the highest reliability reported at that power level. [2015-0237]

There is limited information on the incidence, management, and prognostic impact of new-onset atrial fibrillation (NOAF) following transcatheter aortic valve implantation (TAVI) for severe aortic valve stenosis. In the prospective ASAN-TAVI registry, we evaluated a total of 347 consecutive patients who underwent TAVI from March 2010 to August 2017. The primary end point was a composite of stroke or systemic embolism at 12 months. The study subjects were categorized into 3 groups; pre-existing AF (50 patients), NOAF (31 patients), and non-AF (266 patients) group. NOAF developed in 10.4% of patients without pre-existing AF after TAVI and most cases were paroxysmal type (93.6%). Pharmacologic and electrical cardioversion were tried in 13 (41.9%) and 6 (19.4%) patients and success rates were 61.5% and 33.3%, respectively. NOAF-associated case rate for primary end point was 22.6%. Transfemoral access and cardiac tamponade were independent predictors of NOAF. Patients with NOAF, as compared with those with pre-existing AF and those without AF, had an increased 1-year rate of primary end point (24.0% vs 9.9% vs 7.2%, respectively; p0.001). By multivariable analysis, NOAF was an independent predictor of 1-year rate of primary end point (adjusted hazard ratio: 3.31; 95% CI: 1.34 to 8.20; p = 0.010). In conclusion, patients with severe aortic valve stenosis who underwent TAVI, NOAF occurred in 10% and 1 of 4 NOAF patients experienced stroke or systemic embolization. The presence of NOAF was associated with a substantially higher risk of stroke or systemic embolization.

Background Comparative outcomes of coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) for left main coronary artery (LMCA) disease were previously reported. However, data on very long-term (>10 years) outcomes are limited. Objectives The authors compare 10-year outcomes after PCI and CABG for LMCA disease. Methods In this observational study of the MAIN-COMPARE (Revascularization for Unprotected Left Main Coronary Artery Stenosis: Comparison of Percutaneous Coronary Angioplasty versus Surgical Revascularization) registry, the authors evaluated 2,240 patients with unprotected LMCA disease who underwent PCI (n = 1,102) or underwent CABG (n = 1,138) between January 2000 and June 2006. Adverse outcomes (death; a composite outcome of death, Q-wave myocardial infarction, or stroke; and target-vessel revascularization) were compared with the use of propensity scores and inverse-probability-weighting adjustment. The follow-up was extended to at least 10 years of all patients (median 12.0 years). Results In the overall cohort, there was no significant difference in adjusted risks of death and the composite outcome between the groups up to 10 years. The risk of target-vessel revascularization was significantly higher in the PCI group. In the cohort comparing drug-eluting stents and concurrent CABG, the 2 study groups did not differ significantly in the risks of death and the composite outcome at 5 years. However, after 5 years, drug-eluting stents were associated with higher risks of death (hazard ratio: 1.35; 95% confidence interval: 1.00 to 1.81) and the composite outcome (hazard ratio: 1.46; 95% confidence interval: 1.10 to 1.94) compared with CABG. Conclusions In patients with significant LMCA disease, as compared with CABG, PCI showed similar rates of death and serious composite outcomes, but a higher rate of target-vessel revascularization at 10 years. However, CABG showed lower mortality and serious composite outcome rates compared with PCI with drug-eluting stents after 5 years. (Revascularization for Unprotected Left Main Coronary Artery Stenosis: Comparison of Percutaneous Coronary Angioplasty versus Surgical Revascularization [MAIN-COMPARE]; NCT02791412)

This paper reports a unique 4-terminal MEMS relay (actuation is electrically isolated with signal passage) employing a novel one-contact design to overcome high contact resistance problem of the conventional 4-terminal MEMS relay which utilizes a typical two-contact design. The fabricated 4-terminal MEMS relay with the one-contact design demonstrated a contact resistance of 18 mΩ, which is two order-of-magnitude lower value than that of the conventional two-contact design. To the best of our knowledge, this result is the lowest value in the 4-terminal MEMS relay and comparable value with the state-of-the-art in 3-terminal MEMS relay [14]. In addition, the relay was operated up to 1.1 × 106 cycles at 1 V / 50 mA in an air and hot switching condition with negligible contact resistance variation. The lifetime is 10 times longer than that of the conventional 4-terminal MEMS relay.

Since a microelectromechanical (MEM) switch with an electrostatically actuated cantilever was first demonstrated by Petersen in 1978 [1], MEM switches have actively been researched by many research groups. However, comparing with the conventional metal-oxide-semiconductor field-effect transistor (MOSFET), MEM switches are still suffering from their high actuation voltage and insufficient operational reliability, which still remain as a difficult challenge to many MEMS researchers and hinder commercialization of the MEM switches. In this work, we look at what lies behind these difficulties in MEM switches and illustrate bright ideas that have been sought to enhance the actuation voltage and switch endurance (lifetime) problems.