Prognostic and Safety Implications of Renin-Angiotensin-Aldosterone System Inhibitors in Hypertrophic Cardiomyopathy: A Real-World Observation Over 2,000 Patients

Background and Objectives@#The prognostic or safety implication of renin-angiotensinaldosterone system inhibitors (RASi) in hypertrophic cardiomyopathy (HCM) are not well established, mainly due to concerns regarding left ventricular outflow tract (LVOT) obstruction aggravation. We investigated the implications of RASi in a sizable number of HCM patients. @*Methods@#We enrolled 2,104 consecutive patients diagnosed with HCM in 2 tertiary university hospitals and followed up for five years. RASi use was defined as the administration of RASi after diagnostic confirmation of HCM. The primary and secondary outcomes were all-cause mortality and hospitalization for heart failure (HHF). @*Results@#RASi were prescribed to 762 patients (36.2%). During a median follow-up of 48.1months, 112 patients (5.3%) died, and 94 patients (4.5%) experienced HHF. Patients using RASi had less favorable baseline characteristics than those not using RASi, such as older age, more frequent history of comorbidities, and lower ejection fraction. Nonetheless, there was no difference in clinical outcomes between patients with and without RASi use (log-rank p=0.368 for all-cause mortality and log-rank p=0.443 for HHF). In multivariable analysis, patients taking RASi showed a comparable risk of all-cause mortality (hazard ratio [HR], 0.70, 95% confidence interval [CI], 0.43–1.14, p=0.150) and HHF (HR, 1.03, 95% CI, 0.63–1.70, p=0.900). In the subgroup analysis, there was no significant interaction of RASi use between subgroups stratified by LVOT obstruction, left ventricular (LV) ejection fraction, or maximal LV wall thickness. @*Conclusions@#RASi use was not associated with worse clinical outcomes. It might be safely administered in patients with HCM if clinically indicated.

Long-term cardiovascular events in hypertensive patients: full report of the Korean Hypertension Cohort

Background/Aims@#This study evaluated the long-term cardiovascular complications among Korean patients with hypertension and compared them with that of controls without hypertension. @*Methods@#The Korean Hypertension Cohort (KHC) enrolled 11,043 patients with hypertension and followed them for more than 10 years. Age- and sex-matched controls without hypertension were enrolled at a 1:10 ratio. We compared the incidence of cardiovascular events and death among patients and controls without hypertension. @*Results@#The mean age was 59 years, and 34.8% and 16.5% of the patients belonged to the high and moderate cardiovascular risk groups, respectively. During the 10-year follow-up, 1,591 cardiovascular events (14.4%) with 588 deaths (5.3%) occurred among patients with hypertension and 7,635 cardiovascular events (6.9%) with 4,826 deaths (4.4%) occurred among controls. Even the low-risk population with hypertension showed a higher cardiovascular event rate than the population without hypertension. Although blood pressure measurements in the clinic showed remarkable inaccuracy compared with those measured in the national health examinations, systolic blood pressure (SBP) ≥ 150 mmHg was significantly associated with a higher risk of cardiovascular events. @*Conclusions@#This long-term follow-up study confirmed the cardiovascular event rates among Korean hypertensive patients were substantial, reaching 15% in 10 years. SBP levels ≥ 150 mmHg were highly associated with occurrence of cardiovascular event rates.

The Korean Hypertension Cohort study: design and baseline characteristics

Background/Aims@#Hypertension (HT) has a significant impact on public health and medical expenses. However, HT is a chronic disease that requires the long-term follow-up of a large number of patients. @*Methods@#The Korean Hypertension Cohort (KHC) study aimed to develop a model for calculating cardiovascular risk in HT patients by linking and utilizing the detailed clinical and longitudinal data from hospitals and the national health insurance claim database, respectively. This cohort had a planned sample size of over 11,000 HT patients and 100,000 non-HT controls. Eligible patients were hypertensive patients, who were presenting for the first time and were diagnosed with HT as a main disease from 2006 to 2011. Long-term survival data over a period of approximately 9 years were obtained from the national health insurance claim and national health examination data. @*Results@#This cohort enrolled 11,083 patients with HT. The mean age was 58.87 ± 11.5 years, 50.5% were male, and 31.4% were never-treated HT. Of the enrolled patients, 32.9% and 37.7% belonged to the high and moderate cardiovascular risk groups, respectively. Initial blood pressures were 149.4 ± 18.5/88.5 ± 12.5 mmHg. During the 2 years hospital data follow-up period, blood pressures lowered to 130.8 ± 14.1/78.0 ± 9.7 mmHg with 1.9 ± 1.0 tablet doses of antihypertensive medication. Cardiovascular events occurred in 7.5% of the overall patients; 8.5%, 8.8%, and 4.7% in the high, moderate, and low risk patients, respectively. @*Conclusions@#The KHC study has provided important information on the long-term outcomes of HT patients according to the blood pressure, comorbid diseases, medication, and adherence, as well as health behaviors and health resource use.

Progression of ascending aortopathy may not occur after transcatheter aortic valve replacement in severe bicuspid aortic stenosis

Background/Aims@#We evaluated changes in the ascending aorta dimension post-transcatheter aortic valve replacement (TAVR) in bicuspid aortic valve (BiAV) and tricuspid aortic valve (TAV) patients. @*Methods@#Patients with severe aortic stenosis undergoing TAVR at Seoul National University Hospital were consecutively recruited. Patients with less than 12 months’ follow-up and/or with an ascending aorta size larger than 50 mm were excluded. The ascending aorta size was measured on a parasternal long axis view using transthoracic echocardiography. @*Results@#Among the 67 patients who were included (age: 76.5 ± 6.5 years; male: 52.2%; AV area: 0.67 ± 0.15 cm2), 19 (28.4%) had BiAV; 48 (71.6%) had TAV. The median (interquartile ranges) follow-up duration was 398 days (361 to 451). BiAV patients were younger (73.2 ± 7.2 vs. 77.8 ± 5.8, p = 0.008), and had lower incidences of chronic renal disease (5.3% vs. 35.4%, p = 0.014) and history of coronary intervention (15.8% vs. 50.0%, p = 0.013), than TAV patients. On pre-procedural echocardiography, the ascending aorta dimensions in BiAV patients were larger than those in TAV patients (40.5 ± 3.8 mm vs. 35.9 ± 4.2 mm, p < 0.005). The ascending aorta dimension changed minimally during follow-up; post-TAVR, the ascending aorta’s growth rate was –0.11 ± 1.9 and 0.26 ± 1.8 mm/yr in patients with BiAV and TAV, respectively (p = 0.50). Progression of the ascending aorta’s dimension postTAVR was not clinically significant in BiAV patients. @*Conclusions@#The concern about the progression of aortopathy in BiAV patients post-TAVR may not be a clinical issue. This should be confirmed in studies with a larger population and with a longer follow-up duration.

The Korean Hypertension Cohort study: design and baseline characteristics

Background/Aims@#Hypertension (HT) has a significant impact on public health and medical expenses. However, HT is a chronic disease that requires the long-term follow-up of a large number of patients. @*Methods@#The Korean Hypertension Cohort (KHC) study aimed to develop a model for calculating cardiovascular risk in HT patients by linking and utilizing the detailed clinical and longitudinal data from hospitals and the national health insurance claim database, respectively. This cohort had a planned sample size of over 11,000 HT patients and 100,000 non-HT controls. Eligible patients were hypertensive patients, who were presenting for the first time and were diagnosed with HT as a main disease from 2006 to 2011. Long-term survival data over a period of approximately 9 years were obtained from the national health insurance claim and national health examination data. @*Results@#This cohort enrolled 11,083 patients with HT. The mean age was 58.87 ± 11.5 years, 50.5% were male, and 31.4% were never-treated HT. Of the enrolled patients, 32.9% and 37.7% belonged to the high and moderate cardiovascular risk groups, respectively. Initial blood pressures were 149.4 ± 18.5/88.5 ± 12.5 mmHg. During the 2 years hospital data follow-up period, blood pressures lowered to 130.8 ± 14.1/78.0 ± 9.7 mmHg with 1.9 ± 1.0 tablet doses of antihypertensive medication. Cardiovascular events occurred in 7.5% of the overall patients; 8.5%, 8.8%, and 4.7% in the high, moderate, and low risk patients, respectively. @*Conclusions@#The KHC study has provided important information on the long-term outcomes of HT patients according to the blood pressure, comorbid diseases, medication, and adherence, as well as health behaviors and health resource use.

Early Surgery versus Watchful Waiting in Patients with Moderate Aortic Stenosis and Left Ventricular Systolic Dysfunction

Background and Objectives@#Severe aortic stenosis (AS) with left ventricular systolic dysfunction (LVSD) is a class I indication for aortic valve replacement (AVR) but this recommendation is not well established in those at the stage of moderate AS. We investigate the clinical impact of AVR among patients with moderate AS and LVSD. @*Methods@#From 2001 to 2017, we consecutively identified patients with moderate AS and LVSD, defined as aortic valve area 1.0–1.5 cm2 and left ventricular ejection fraction <50%. The primary outcome was all-cause death. The outcomes were compared between those who underwent early surgical AVR (within 2 years of index echocardiography) at the stage of moderate AS versus those who were followed medically without AVR at the outpatient clinic. @*Results@#Among 255 patients (70.1±11.3 years, male 62%), 37 patients received early AVR. The early AVR group was younger than the medical observation group (63.1±7.9 vs. 71.3±11.4) with a lower prevalence of hypertension and chronic kidney disease. During a median 1.8-year follow up, 121 patients (47.5%) died, and the early AVR group showed a significantly lower all-cause death rate than the medical observation group (5.03PY vs. 18.80PY, p<0.001). After multivariable Cox-proportional hazard regression adjusting for age, sex, comorbidities, and laboratory data, early AVR at the stage of moderate AS significantly reduced the risk of death (hazard ratio, 0.43; 95% confidence interval 0.20–0.91; p=0.028). @*Conclusions@#In patients with moderate AS and LVSD, AVR reduces the risk of all-cause death. A prospective randomized trial is warranted to confirm our findings.

Cardiac Magnetic Resonance Feature Tracking in Aortic Stenosis: Exploration of Strain Parameters and Prognostic Value in Asymptomatic Patients with Preserved Ejection Fraction

OBJECTIVE: To determine the most valuable cardiac magnetic resonance feature tracking (CMR-FT) parameters for evaluating aortic stenosis (AS) and determine whether they can predict the prognosis in asymptomatic AS patients with preserved ejection fraction (pEF).MATERIALS AND METHODS: A prospective cohort of 123 moderate to severe AS patients (60 males, 68.6 ± 9.2 years) and 32 control subjects (14 males, 67.9 ± 4.4 years) underwent echocardiography and 3T CMR imaging from 2011–2015. CMR cine images were analyzed using CMR-FT to assess the left ventricular radial, circumferential, and longitudinal peak strain (PS) in 2- and 3-dimensions. The primary endpoints were clinical cardiac events (CCEs), including cardiac death, heart failure, and AS-associated symptom development. For statistical analysis, logistic regression and log-rank tests were used.RESULTS: Global PSs differed between AS patients and controls and between severe and moderate AS patients (p < 0.05). Two-dimensional (2D) global radial and longitudinal PSs changed gradually with the severity of AS groups (p < 0.001). Twenty-two of 67 asymptomatic AS patients with pEF experienced CCEs during the follow-up (median: 31.1 months). 2D global longitudinal PS (GLPS) was the single risk factor for CCE (p = 0.017). The relative risk for CCE was 3.9 (p = 0.016, 95% confidence interval: 1.2–11.9) based on 2D GLPS with a cutoff of −17.9% according to receiver operating characteristic curve analysis. Survival analysis demonstrated that asymptomatic AS patients with pEF having impaired 2D GLPS experienced worse event-free survival than the others (p = 0.041).CONCLUSION: 2D global longitudinal and radial PSs may reflect cardiac dysfunction according to the degree of AS. 2D GLPS might be a prognostic predictor of CCEs in asymptomatic AS patients with pEF.

Fabry Disease that Phenocopies Hypertrophic Cardiomyopathy: a thorough Genetic ‘Detective’ Identifies the ‘Rogue’ Hidden in the GLA Gene

No abstract available.

Coronary Computed Tomography Angiography for the Diagnosis of Vasospastic Angina: Comparison with Invasive Coronary Angiography and Ergonovine Provocation Test

OBJECTIVE: To investigate the diagnostic validity of coronary computed tomography angiography (cCTA) in vasospastic angina (VA) and factors associated with discrepant results between invasive coronary angiography with the ergonovine provocation test (iCAG-EPT) and cCTA. MATERIALS AND METHODS: Of the 1397 patients diagnosed with VA from 2006 to 2016, 33 patients (75 lesions) with available cCTA data from within 6 months before iCAG-EPT were included. The severity of spasm (% diameter stenosis [%DS]) on iCAG-EPT and cCTA was assessed, and the difference in %DS (Δ%DS) was calculated. Δ%DS was compared after classifying the lesions according to pre-cCTA-administered sublingual nitroglycerin (SL-NG) or beta-blockers. The lesions were further categorized with %DS ≥ 50% on iCAG-EPT or cCTA defined as a significant spasm, and the diagnostic performance of cCTA on identifying significant spasm relative to iCAG-EPT was assessed. RESULTS: Compared to lesions without SL-NG treatment, those with SL-NG treatment showed a higher Δ%DS (39.2% vs. 22.1%, p = 0.002). However, there was no difference in Δ%DS with or without beta-blocker treatment (35.1% vs. 32.6%, p = 0.643). The significant difference in Δ%DS associated with SL-NG was more prominent in patients who were aged < 60 years, were male, had body mass index < 25 kg/m2, and had no history of hypertension, diabetes, or dyslipidemia. Based on iCAG-EPT as the reference, the per-lesion-based sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of cCTA for VA diagnosis were 7.5%, 94.0%, 60.0%, 47.1%, and 48.0%, respectively. CONCLUSION: For patients with clinically suspected VA, confirmation with iCAG-EPT needs to be considered without completely excluding the diagnosis of VA simply based on cCTA results, although further prospective studies are required for confirmation.

Study Design for the 2016 Baseline Survey of a Health System Strengthening Project in Quoc Oai District, Hanoi, Vietnam

BACKGROUND: In order to provide essential scientific evidence on the population's health status and social health determinants as well as the current capacity of the health care system in Vietnam to health policy makers and managers, Vietnam Ministry of Health, Hanoi University of Public Health, Hanoi Medical University, and Ho Chi Minh University of Medicine and Pharmacy collaborated with Seoul National University (Korea) and conducted a health system survey in the Quoc Oai district (of Hanoi capital) that represented northern rural Vietnam. METHODS: The study design was a cross-sectional study. The survey covered different topics (more than 200 questions) and was administered in three separate questionnaires: 1) Basic information of all household members; 2) Household characteristics; and 3) Individual characteristics. Socio-demographic characteristics among the households and individuals were collected from 2,400 households sampled by multi-stage cluster sampling method: more than 200 questions. RESULTS: The household size of Quoc Oai was larger than the national average and there was no significant difference in gender composition. In addition, the proportions of pre-elderly, age 55–64, and elderly group (65 years old and over) were higher than the national population statistics. In this context, demographic transition has begun in Quoc Oai. CONCLUSION: This study design description provides the basic information about a baseline survey of a future prospective cohort (as a part of a collaborative project on strengthening the health system in Vietnam) to the prospective data user of this survey.

Clinical Characteristics of Korean Patients with Bicuspid Aortic Valve Who Underwent Aortic Valve Surgery

BACKGROUND AND OBJECTIVES: Clinical data for Korean patients with bicuspid aortic valve (BAV) that underwent aortic valve (AV) surgery are currently limited. METHODS: Data for 1,160 consecutive adult BAV patients who underwent AV surgery from 2000 to 2014 in 4 tertiary referral centers were retrospectively analyzed. A standard case report form was used for clinical and echocardiographic parameters. RESULTS: Mean age at the time of AV surgery was 59±13 years. The most common cause of AV surgery was aortic stenosis (AS, 892 [77%]), followed by aortic regurgitation (AR, 199 [17%]), and infective endocarditis (69 [6%]). AS showed a skewed peak in the aged population and was the predominant cause of AV surgery (87%) in patients ≥50 years of age, whereas AR (46%) and active infective endocarditis (19%) were more common in younger patients (p < 0.001). Echocardiographic determination of the BAV phenotype revealed that fusion of the right coronary cusp (RCC) and left coronary cusp (LCC) was most common (622 [53%]), followed by fusion of RCC and non-coronary cusp (NCC) (313 [27%]), and fusion of LCC and NCC (42 [4%]); the BAV phenotype could not be determined in the remaining 183 patients (16%). Fusion of RCC and LCC was more commonly observed in patients with AR than in those with AS (74% vs. 49%; p < 0.001). CONCLUSION: BAV patients were characterized by distinct surgical indications according to their age. Possible associations between BAV phenotypes and surgical indications with potential impacts of ethnicity need to be tested in further studies.

A comparison of the accuracy of intraoral scanners using an intraoral environment simulator

PURPOSE: The aim of this study was to design an intraoral environment simulator and to assess the accuracy of two intraoral scanners using the simulator. MATERIALS AND METHODS: A box-shaped intraoral environment simulator was designed to simulate two specific intraoral environments. The cast was scanned 10 times by Identica Blue (MEDIT, Seoul, South Korea), TRIOS (3Shape, Copenhagen, Denmark), and CS3500 (Carestream Dental, Georgia, USA) scanners in the two simulated groups. The distances between the left and right canines (D3), first molars (D6), second molars (D7), and the left canine and left second molar (D37) were measured. The distance data were analyzed by the Kruskal-Wallis test. RESULTS: The differences in intraoral environments were not statistically significant (P>.05). Between intraoral scanners, statistically significant differences (P < .05) were revealed by the Kruskal-Wallis test with regard to D3 and D6. CONCLUSION: No difference due to the intraoral environment was revealed. The simulator will contribute to the higher accuracy of intraoral scanners in the future.

Maxillary first molar wear: a longitudinal study of children / 대한해부학회지

The aim of this study is to examine the correlation between tooth wear and age by quantitatively measuring maxillary first molar wear in children. A total of 150 maxillary dental models were analyzed in 30 subjects (male, 11; female, 19) with an age range of 6–14 years. Maxillary first molar wear were assessed based on area, volume and the shortest distance from the buccal occlusal plane to the central pit point (BCPH). The area and volume of the tooth cusps were measured at four different offset-plane heights (0.2, 0.4, 0.6, and 0.8 mm). Relationship between age and the amount of wear or BCPH were statistically analyzed. Correlation and regression analyses were also performed, and age estimation was obtained with linear regression analysis. Repeated measures analysis of variance (ANOVA) revealed significant differences between age and the amount of wear based on area, volume, and offset-plane height. Except age of 8 and 10, 12 and 14's 0.2-mm offset-plane-measured volume, all area and volume measurement of all ages and offset-plane height showed a significant amount of increase. Wear speeds were calculated using the BCPH. Among age and measurement variables, the correlation coefficient was strongest when the volume was measured from the 0.4-mm offset-plane. As age increases, the amount of wear, as quantified by area and volume measurements, also increases. According to this study, a regression equation that can be used for age estimation is follows: Age (y)=0.16×0.4V+0.85 (R²=0.490) using volume.

Clinical Characteristics of Korean Patients with Bicuspid Aortic Valve Who Underwent Aortic Valve Surgery

BACKGROUND AND OBJECTIVES@#Clinical data for Korean patients with bicuspid aortic valve (BAV) that underwent aortic valve (AV) surgery are currently limited.@*METHODS@#Data for 1,160 consecutive adult BAV patients who underwent AV surgery from 2000 to 2014 in 4 tertiary referral centers were retrospectively analyzed. A standard case report form was used for clinical and echocardiographic parameters.@*RESULTS@#Mean age at the time of AV surgery was 59±13 years. The most common cause of AV surgery was aortic stenosis (AS, 892 [77%]), followed by aortic regurgitation (AR, 199 [17%]), and infective endocarditis (69 [6%]). AS showed a skewed peak in the aged population and was the predominant cause of AV surgery (87%) in patients ≥50 years of age, whereas AR (46%) and active infective endocarditis (19%) were more common in younger patients (p < 0.001). Echocardiographic determination of the BAV phenotype revealed that fusion of the right coronary cusp (RCC) and left coronary cusp (LCC) was most common (622 [53%]), followed by fusion of RCC and non-coronary cusp (NCC) (313 [27%]), and fusion of LCC and NCC (42 [4%]); the BAV phenotype could not be determined in the remaining 183 patients (16%). Fusion of RCC and LCC was more commonly observed in patients with AR than in those with AS (74% vs. 49%; p < 0.001).@*CONCLUSION@#BAV patients were characterized by distinct surgical indications according to their age. Possible associations between BAV phenotypes and surgical indications with potential impacts of ethnicity need to be tested in further studies.

Methods for quantitative measurement of tooth wear using the area and volume of virtual model cusps

PURPOSE: Clinicians must examine tooth wear to make a proper diagnosis. However, qualitative methods of measuring tooth wear have many disadvantages. Therefore, this study aimed to develop and evaluate quantitative parameters using the cusp area and volume of virtual dental models. METHODS: The subjects of this study were the same virtual models that were used in our former study. The same age group classification and new tooth wear index (NTWI) scoring system were also reused. A virtual occlusal plane was generated with the highest cusp points and lowered vertically from 0.2 to 0.8 mm to create offset planes. The area and volume of each cusp was then measured and added together. In addition to the former analysis, the differential features of each cusp were analyzed. RESULTS: The scores of the new parameters differentiated the age and NTWI groups better than those analyzed in the former study. The Spearman ρ coefficients between the total area and the area of each cusp also showed higher scores at the levels of 0.6 mm (0.6A) and 0.8A. The mesiolingual cusp (MLC) showed a statistically significant difference (P < 0.01) from the other cusps in the paired t-test. Additionally, the MLC exhibited the highest percentage of change at 0.6A in some age and NTWI groups. Regarding the age groups, the MLC showed the highest score in groups 1 and 2. For the NTWI groups, the MLC was not significantly different in groups 3 and 4. These results support the proposal that the lingual cusp exhibits rapid wear because it serves as a functional cusp. CONCLUSIONS: Although this study has limitations due to its cross-sectional nature, it suggests better quantitative parameters and analytical tools for the characteristics of cusp wear.

Questionnaire survey for the clinical trial participants who experienced both digital and conventional impression

PURPOSE: The aim of this study was to assess the patients' perception, acceptance, and preference of the difference between a conventional impression and digital impression through questionnaire survey. MATERIALS AND METHODS: Thirteen (6 male, 7 female) subjects who experienced both digital and conventional impression at the same day were enrolled in this study. Conventional impression were taken with polyvinylsiloxane and digital impression were performed using a newly developed intra-oral scanner. Immediately after the two impressions were made, a survey was conducted with the standardized questionnaires consisting of the following three categories; 1) general dental treatment 2) satisfaction of conventional impression 3) satisfaction of digital impression. The perceived source of satisfaction was evaluated using Likert scale. The distribution of the answers was assessed by percentages and statistical analyses were performed with the paired t-test, and P < 0.05 was considered significant. RESULTS: There were significant differences of the overall satisfaction between two impression methods (P < 0.05). Digital impression showed high satisfaction in less shortness of breath and odor to participants compared to conventional impression. The use of an oral scanner resulted in a discomfort of TMJ due to prolonged mouth opening and in lower score of the scanner tip size. CONCLUSION: It was confirmed that the preference for the digital impression using intraoral scanner is higher than the conventional impression. Most survey participants said they would recommend the digital impression to others and said they preferred it for future prosthetic treatment.

Erratum: Comparative study on quality of scanned images from varying materials and surface conditions of standardized model for dental scanner evaluation

No abstract available.

Comparative study on quality of scanned images from varying materials and surface conditions of standardized model for dental scanner evaluation

PURPOSE: The purpose of this study is to evaluate the image acquisition ability of intraoral scanners by analyzing the comprehensiveness of scanned images from standardized model, and to identify problems of the model. MATERIALS AND METHODS: Cast models and 3D-printed models were prepared according to international standards set by ISO12836 and ANSI/ADA no. 132, which were then scanned by model scanner and two different intraoral scanners (TRIOS3 and CS3500). The image acquisition performance of the scanners was classified into three grades, and the study was repeated with varying surface conditions of the models. RESULTS: Model scanner produced the most accurate images in all models. Meanwhile, CS3500 showed good image reproducibility for angled structures and TRIOS3 showed good image reproducibility for rounded structures. As for model ingredients, improved plaster model best reproduced scan images regardless of the type of scanner used. When limited to 3D-printed model, powdered surface condition resulted in higher image quality. CONCLUSION: When scanning structures beyond FOV (field of view) in standardized models (following ISO12836 and ANSI/ADA 132), lack of reference points to help distinguish different faces confuses the scanning and matching process, resulting in inaccurate display of images. These results imply the need to develop a new standard model not confined to simple pattern repetition and symmetric structure.

Echocardiographic Predictors for Left Ventricular Remodeling after Acute ST Elevation Myocardial Infarction with Low Risk Group: Speckle Tracking Analysis

BACKGROUND: We sought to assess echocardiographic predictors of left ventricular (LV) adverse remodeling after successfully reperfused acute ST elevation myocardial infarction (STEMI). LV remodeling is commonly found in STEMI patients and it may suggest adverse outcome in acute myocardial infarction. We sought to identify whether 2D strain and torsion be independent parameters for prediction of LV adverse remodeling. METHODS: We investigated 208 patients with low-risk STEMI patients who had follow up echocardiography at 6 or more months. After clinical assessments, all patients received revascularization according to current guideline. LV remodeling was defined as > 20% increase in end-diastolic volume (EDV) at follow up. RESULTS: During the follow-up (11.9 ± 5.3 months), 53 patients (25.5%) showed LV remodeling. In univariate analysis, EDV, end-systolic volume, deceleration time (DT), CK-MB, and global longitudinal strain (GLS) were associated with LV remodeling. In multivariate analysis, EDV [hazard ratio (HR): 0.922, 95% confidence interval (CI): 0.897-0.948, p< 0.001], GLS (HR: 0.842, 95% CI: 0.728-0.974, p = 0.020), DT (HR: 0.989, 95% CI: 0.980-0.998, p = 0.023) and CK-MB (HR: 1.003, 95% CI: 1.000-1.005, p = 0.033) independently predicted LV remodeling. However, global circumferential strain, net twist, and twist or untwist rate were not associated with remodeling. CONCLUSION: Of various parameters of speckle strain, only GLS predicted adverse remodeling in STEMI patients.

The user-friendly, ergonomic design aspect of recent intraoral scanners: a literature review

Recently, traditional impression has been rapidly replaced by digital impression using intraoral scanning. There are more than 7 types of intraoral scanners available in the dental market. It is difficult to make effective strategic choices due to a lack of standards and guidelines for optimal intraoral scanning devices. So far, little has been reported about evaluating the ergonomic aspect of these scanners. This literature review compares current intraoral scanning systems based on different types of handles and suggests the most comfortable, user-friendly intraoral scanners from an ergonomic standpoint.