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1.
Korean Circ J ; 54(6): 311-322, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38863251

ABSTRACT

BACKGROUND AND OBJECTIVES: Early diastolic mitral annular tissue (e') velocity is a commonly used marker of left ventricular (LV) diastolic function. This study aimed to investigate the prognostic implications of e' velocity in patients with mitral regurgitation (MR). METHODS: This retrospective cohort study included 1,536 consecutive patients aged <65 years with moderate or severe chronic primary MR diagnosed between 2009 and 2018. The primary and secondary outcomes were all-cause and cardiovascular mortality, respectively. According to the current guidelines, the cut-off value of e' velocity was defined as 7 cm/s. RESULTS: A total of 404 individuals were enrolled (median age, 51.0 years; 64.1% male; 47.8% severe MR). During a median 6.0-year follow-up, there were 40 all-cause mortality and 16 cardiovascular deaths. Multivariate analysis revealed a significant association between e' velocity and all-cause death (adjusted hazard ratio [aHR], 0.770; 95% confidence interval [CI], 0.634-0.935; p=0.008) and cardiovascular death (aHR, 0.690; 95% CI, 0.477-0.998; p=0.049). Abnormal e' velocity (≤7 cm/s) independently predicted all-cause death (aHR, 2.467; 95% CI, 1.170-5.200; p=0.018) and cardiovascular death (aHR, 5.021; 95% CI, 1.189-21.211; p=0.028), regardless of symptoms, LV dimension and ejection fraction. Subgroup analysis according to sex, MR severity, mitral valve replacement/repair, and symptoms, showed no significant interactions. Including e' velocity in the 10-year risk score improved reclassification for mortality (net reclassification improvement [NRI], 0.154; 95% CI, 0.308-0.910; p<0.001) and cardiovascular death (NRI, 1.018; 95% CI, 0.680-1.356; p<0.001). CONCLUSIONS: In patients aged <65 years with primary MR, e' velocity served as an independent predictor of all-cause and cardiovascular deaths.

2.
RSC Adv ; 14(5): 3473-3479, 2024 Jan 17.
Article in English | MEDLINE | ID: mdl-38260000

ABSTRACT

In this work, we used a one-step hydrothermal method to synthesize blue-emission sulfur-doped carbon dots (S-CDs) using jaggery as a carbon precursor. The synthesized carbon quantum dots showed low toxicity, good water solubility, anti-interference properties, and stable fluorescence. When excited at 310 nm, the S-CDs produced bright emission with a quantum yield of 7.15% at 397 nm. The S-CDs exhibited selective and sensitive quenching responses with limits of detection (LODs) of 4.25 µg mL-1 and 3.15 µg mL-1 for variable concentrations of Cr6+ and Fe3+, respectively, accompanied by a consistent linear relationship between fluorescence intensity and these concentrations. Fluorescence lifetime measurements were used to investigate the fluorescence quenching mechanism, which supports the static type of quenching. Outstanding benefits of the developed S-CD based fluorescence probe include its low cost, excellent sensitivity and selectivity, and ease of use for the detection of Cr6+ and Fe3+ ions. The developed carbon dot based fluorescent probe was successfully used to detect Cr6+ and Fe3+ ions in real water samples with an excellent recovery ratio.

3.
Int J Biol Macromol ; 257(Pt 1): 128126, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37981273

ABSTRACT

The present investigation explores the different pathways for development of waste tea residue carbon dots (WTR-CDs) loading into hydrogel matrix for WTR-CDs releasing probe. Fluorescent WTR-CDs incorporated into hydrogel matrix were synthesized by valorisation of kitchen waste tea by simple carbonization method (λem = 450 nm, ΦWTR-CDs =18.45 %). Biopolymeric alginate-based hydrogel beads (HB-Alg) were prepared by simple extrusion method. Three routes (ex-situ/in-situ) were employed for loading of WTR-CDs into hydrogel matrix. Successful synthesis of WTR-CDs and its loading into hydrogel matrix was confirmed via various characterization techniques. Developed protocol was employed for stimuli-responsive cumulative release of WTR-CDs study (pH = 3.0, 7.4, 9.0) was monitored over 7 days. Results suggests that, the HB-Alg@WTR-CDs-A system with in-situ loaded WTR-CDs have sustained release due to ionic interaction of WTR-CDs with crosslinked polymer network, whereas in HB-Alg@WTR-CDs-B, WTR-CDs loaded in wet-beads having burst release in which loosely bound WTR-CDs into hydrogel cavities releases rapidly. While, in case of HB-Alg@WTR-CDs-C, lowest release was observed due to weakly surface bound WTR-CDs, low loading and shrinkage of pores into dry-beads. Radical scavenging activity was studied and shown antioxidant properties of WTR-Powder, WTR-CDs and HB-Alg@WTR-CDs-A,B,C. Cytotoxicity of all systems was checked via CAM assay and significant growth in blood vascularization with no loss of chick embryo confirming the released WTR-CDs are biocompatible. Successful investigation and summarization of results ensure that, waste-valorisation, simple, sustainable, and smart hydrogel systems with different routes of WTR-CDs loading have opened a window to understand the mechanistic pathways in release behaviour. This robust approach for improvement of smarter and biocompatible materials can be fruitfully applicable in advanced, controlled and stimuli responsive delivery probes.


Subject(s)
Alginates , Hydrogels , Chick Embryo , Animals , Alginates/chemistry , Hydrogels/chemistry , Carbon , Biocompatible Materials/chemistry , Tea
4.
Heart ; 109(15): 1132-1138, 2023 07 12.
Article in English | MEDLINE | ID: mdl-36631144

ABSTRACT

The diagnostic yield of endomyocardial biopsy in cardiac sarcoidosis (CS) is quite low because of the patchy involvement, and for the diagnosis of CS, existing guidelines required histological confirmation. Therefore, especially for isolated CS, diagnosis consistent with the guidelines cannot be made in a large number of patients. With recent developments in imaging modalities such as cardiac magnetic resonance and 18-fluorodeoxyglucose positron emission tomography, diagnosing CS has become easier and diagnostic criteria for CS not compulsorily requiring histological confirmation have been suggested. Despite significant advances in diagnostic tools, large-scale studies that can guide treatment plans are still lacking, and treatment has relied on the experience accumulated over the past years and the consensus of experts. However, opinions vary, depending on the situation, which is quite puzzling for the physician treating CS. Moreover, with the advent of new immunosuppressant agents, these new drugs have been applied under the assumption that the effect of immunosuppression is not much different from that of other well-known autoimmune diseases that require immunosuppression. However, we should wait to see the beneficial effects of these new immunosuppressants before we attempt to apply these agents in our clinical practice. This review summarises the widely used diagnostic criteria, current diagnostic modalities and recommended treatments for sarcoidosis. We have added our opinions on selecting or modifying diagnostic and treatment plans from the diverse current recommendations.


Subject(s)
Cardiomyopathies , Myocarditis , Sarcoidosis , Humans , Cardiomyopathies/diagnosis , Cardiomyopathies/therapy , Cardiomyopathies/pathology , Heart , Positron-Emission Tomography/methods , Sarcoidosis/diagnosis , Sarcoidosis/therapy , Fluorodeoxyglucose F18
5.
JACS Au ; 2(9): 2089-2097, 2022 Sep 26.
Article in English | MEDLINE | ID: mdl-36186563

ABSTRACT

Stable, nitroxide-based organic radicals have gained tremendous attention in a wide range of research fields, ranging from solid-state electronics to energy storage devices. While the success of these organics has been their designer flexibility and the processability that can fully potentiate the open-shell chemistry, a significant knowledge gap exists on the solid-state electronics of small-molecular radicals. Herein, we examine the structure-property relationship that governs the solid-state electronics of a model nitroxide and its derivatives by seeking the connection to their well-established, electrolyte-based chemistry. Further, we propose a general strategy of enhancing their solid-state conductivity by systematic humidity control. This study demonstrates an open-shell platform of the device operation and underlying principles thereof, which can potentially be applied in a number of future radical-based electronic devices.

6.
JACC Cardiovasc Imaging ; 15(6): 974-986, 2022 06.
Article in English | MEDLINE | ID: mdl-35680229

ABSTRACT

BACKGROUND: Topological data analysis (TDA) can generate patient-patient similarity networks by analyzing large, complex data and derive new insights that may not be possible with standard statistics. OBJECTIVES: The purpose of this paper was to discover novel phenotypes of chronic primary mitral regurgitation (MR) patients and to analyze their clinical implications using network analysis of echocardiographic data. METHODS: Patients with chronic moderate to severe primary MR were prospectively enrolled from 11 Asian tertiary hospitals (n = 850; mean age 56.9 ± 14.2 years, 57.9% men). We performed TDA to generate network models using 14 demographic and echocardiographic variables. The patients were grouped by phenotypes in the network, and the prognosis was compared by groups. RESULTS: The network model by TDA revealed 3 distinct phenogroups. Group A was the youngest with fewer comorbidities but increased left ventricular (LV) end-systolic volume, representing compensatory LV dilation commonly seen in chronic primary MR. Group B was the oldest with high blood pressure and a predominant diastolic dysfunction but relatively preserved LV size, an unnoticed phenotype in chronic primary MR. Group C showed advanced LV remodeling with impaired systolic, diastolic function, and LV dilation, indicating advanced chronic primary MR. During follow-up (median 3.5 years), 60 patients received surgery for symptomatic MR or died of cardiovascular causes. Kaplan-Meier curves demonstrated that although group C had the worst clinical outcome (P < 0.001), group B, characterized by diastolic dysfunction, had an event-free survival comparable to group A despite preserved LV chamber size. The grouping information by the network model was an independent predictor for the composite of MR surgery or cardiovascular death (adjusted HR: 1.918; 95% CI: 1.257-2.927; P = 0.003). CONCLUSIONS: The patient-patient similarity network by TDA visualized diverse remodeling patterns in chronic primary MR and revealed distinct phenotypes not emphasized currently. Importantly, diastolic dysfunction deserves equal attention when understanding the clinical presentation of chronic primary MR.


Subject(s)
Mitral Valve Insufficiency , Ventricular Dysfunction, Left , Humans , Mitral Valve , Predictive Value of Tests , Ventricular Dysfunction, Left/diagnostic imaging , Ventricular Dysfunction, Left/etiology , Ventricular Function, Left , Ventricular Remodeling
7.
ACS Appl Mater Interfaces ; 14(10): 12168-12179, 2022 Mar 16.
Article in English | MEDLINE | ID: mdl-35254047

ABSTRACT

The Zn-polyiodide redox flow battery is considered to be a promising aqueous energy storage system. However, in its charging process, the electrode kinetics of I- oxidation often suffer from an intrinsically generated iodine film (I2-F) on the cathode of the battery. Therefore, it is critical to both understand and enhance the observed slow electrode kinetics of I- oxidation by an electrochemically generated I2-F. In this article, we introduced an electrogenerated N-methyl-N-ethyl pyrrolidinium iodide (MEPI)-iodine (I2) solution, designated as MEPIS, and demonstrated that the electrode kinetics of I- oxidation were dramatically enhanced compared to an I2-F under conventional electrolyte conditions, such as NaI. We showed that this result mainly contributed to the fast electro-oxidation of triiodide (I3-), which exists in the shape of a I3--in-I2 network, [I3-·(I2)n]. Raman spectroscopic and electrochemical analyses showed that the composition of electrogenerated MEPIS changed from I3- to [I3-·(I2)n] via I5- as the anodic overpotential increased. We also confirmed that I- was electrochemically oxidized on a MEPIS-modified Pt electrode with fast electrode kinetics, which is clearly contrary to the nature of an I2-F derived from a NaI solution as a kinetic barrier of I- oxidation. Through stochastic MEPIS-particle impact electrochemistry and electrochemical impedance spectroscopy, we revealed that the enhanced electrode kinetics of I- oxidation in MEPIS can be attributed to the facilitated charge transfer of I3- oxidation in [I3-·(I2)n]. In addition, we found that the degree of freedom of I3- in a quaternary ammonium-based I2-F can also be critical to determine the kinetics of the electro-oxidation of I-, which is that MEPIS showed more enhanced charge-transfer kinetics of I- oxidation compared to tetrabutylammonium I3- due to the higher degree of freedom of I3-.

8.
Analyst ; 147(2): 274-281, 2022 Jan 17.
Article in English | MEDLINE | ID: mdl-34889326

ABSTRACT

In this study, we demonstrate an acoustofluidic device that enables single-file focusing of submicron particles and bacteria using a two-dimensional (2D) acoustic standing wave. The device consists of a 100 µm × 100 µm square channel that supports 2D particle focusing in the channel center at an actuation frequency of 7.39 MHz. This higher actuation frequency compared with conventional bulk acoustic systems enables radiation-force-dominant motion of submicron particles and overcomes the classical size limitation (≈2 µm) of acoustic focusing. We present acoustic radiation force-based focusing of particles with diameters less than 0.5 µm at a flow rate of 12 µL min-1, and 1.33 µm particles at flow rates up to 80 µL min-1. The device focused 0.25 µm particles by the 2D acoustic radiation force while undergoing a channel cross-section centered, single-vortex acoustic streaming. A suspension of bacteria was also investigated to evaluate the biological relevance of the device, which demonstrated the alignment of bacteria in the channel at a flow rate of up to 20 µL min-1. The developed acoustofluidic device can align submicron particles within a narrow flow stream in a highly robust manner, validating its use as a flow-through focusing chamber to perform high-throughput and accurate flow cytometry of submicron objects.


Subject(s)
Acoustics , Sound , Bacteria , Flow Cytometry , Particle Size
9.
J Nucl Med ; 63(7): 1064-1069, 2022 07.
Article in English | MEDLINE | ID: mdl-34916248

ABSTRACT

11C-Pittsburgh compound B (PiB) PET/CT visualizes the amount of myocardial amyloid deposit and can be used to prognosticate patients with amyloid light-chain (AL) cardiac amyloidosis (CA). However, whether 11C-PiB PET/CT has any independent additional prognostic value beyond the commonly used biomarkers remains unknown. Methods: This prospective study was on a cohort of 58 consecutive patients with AL CA who underwent 11C-PiB PET/CT. The patients were stratified into 2 groups on the basis of a visual assessment of whether there was myocardial 11C-PiB uptake on PET/CT. The primary endpoint was 1-y overall mortality. The independent prognostic utility of 11C-PiB PET/CT was analyzed using net reclassification improvement and integrated discrimination improvement. Results: Among the 58 patients enrolled, 35 were positive for myocardial 11C-PiB uptake on PET/CT. Patients with myocardial 11C-PiB PET uptake had a worse 1-y overall survival rate than those without (81.8% vs. 45.5%, P = 0.003 by log-rank test). In the multivariate analysis, positivity for myocardial 11C-PiB uptake on PET/CT was an independent predictor of 1-y mortality (adjusted hazard ratio, 3.382; 95% CI, 1.011-11.316; P = 0.048). In analysis of 3 subgroups of patients-those with a troponin I level of at least 0.1 ng/mL, those with an N-terminal pro-B-type natriuretic peptide (NT-proBNP) level of at least 1,800 pg/mL, and those with a difference of at least 180 mg/L between free light chains (the 3 commonly used biomarkers and their thresholds for staging in AL amyloidosis)-Kaplan-Meier curves showed for all 3 subgroups that patients positive for myocardial 11C-PiB uptake on PET/CT had a worse prognosis than those who were negative. Additionally, when the results of 11C-PiB PET/CT were added to these 3 biomarkers, the performance of 1-y mortality prediction significantly improved by net reclassification improvement (troponin I, 0.861; NT-proBNP, 0.914; difference between free light chains, 0.987) and by integrated discrimination improvement (0.200, 0.156, and 0.108, respectively). Conclusion:11C-PiB PET/CT is a strong independent predictor of 1-y overall mortality and provides incremental prognostic benefits beyond the 3 commonly used biomarkers of AL amyloidosis staging. Considering the recent development of numerous amyloid-targeting molecular imaging agents, further investigations are warranted on whether PET/CT should be included in risk stratification for patients with AL CA.


Subject(s)
Amyloidosis , Immunoglobulin Light-chain Amyloidosis , Aniline Compounds , Biomarkers , Humans , Immunoglobulin Light Chains , Peptide Fragments , Positron Emission Tomography Computed Tomography , Prognosis , Prospective Studies , Thiazoles , Troponin I
10.
Sci Rep ; 11(1): 17996, 2021 09 09.
Article in English | MEDLINE | ID: mdl-34504276

ABSTRACT

Herein, for the first time the carbon dots (CDs) were synthesized by reflux method from sawmill waste material. We also represent a novel strategy based on fluorescent CDs for determination of ponceau 4R and allura red dyes in soft drinks. Interestingly, both the dyes were sensitive and showed effective fluorescence quenching of the CDs owing to the interaction between them. The analytical applicability of CDs were evaluated for detection of both the dyes with a good linear relationship between the concentration range of 0.0 to 3.0 µg mL-1 and having detection limit 0.45 and 0.47 µg mL-1 for allura red and ponceau 4R dyes respectively. Meanwhile, the potential application of this novel fluorescent probe for dyes determination in real samples was validated in different soft drink samples with good accuracy and precision. Thus, these findings provides new insights for the potential risk assessment of both the dyes. Moreover, CDs acted as an excellent fluorescent material in cellular imaging owing to their cellular uptake and localization.

11.
BMC Cardiovasc Disord ; 21(1): 187, 2021 04 15.
Article in English | MEDLINE | ID: mdl-33858344

ABSTRACT

BACKGROUND: Coronary computed tomography angiography (CCTA) is widely used as a first-line noninvasive modality that frequently exhibits no or nonobstructive coronary artery disease (CAD) in clinical practice, along with abnormal left ventricular (LV) geometry on echocardiography. However, the combined prognostic value of these findings has not been well elucidated. Therefore, we aimed to evaluate the prognostic implications of abnormal LV geometry in individuals with no or nonobstructive CAD. METHODS: A total of 5806 subjects with no CAD or nonobstructive CAD (luminal narrowing < 50%) on CCTA were included in the study. The major exclusion criteria were structural heart disease and a history of myocardial infarction or coronary revascularization. Abnormal LV geometry on echocardiography was defined as LV mass index > 95 g/m2 in women and > 115 g/m2 in men, and/or relative wall thickness > 0.42. The primary outcome was all-cause mortality. RESULTS: A total of 5803 subjects without significant obstructive CAD (age, 56.6 ± 8.87 years; men, 3884 [66.9%]). Of them, 4045 (69.7%) subjects had normal LV geometry and 1758 (30.3%) had abnormal LV geometry respectively. During a mean follow-up of 6.2 ± 1.48 years, 84 (1.44%) subjects died in the study population. Of these, 56 subjects were from the normal LV geometry group (1.24%) and 28 were from the abnormal LV geometry group (2.32%). Subjects with abnormal LV geometry had significantly worse survival rates (log-rank, p < 0.001). After adjustment for confounding factors, abnormal LV geometry was an independent predictor of all-cause mortality (adjusted hazard ratio, 1.64; 95% confidence interval, 1.04-2.58; p = 0.034). Moreover, abnormal LV geometry was significantly worse in survival when classified as those with no CAD (log-rank, p = 0.024) and nonobstructive CAD (Log-rank, p < 0.001). CONCLUSIONS: Abnormal LV geometry portends a worse prognosis in subjects with no or nonobstructive CAD. These findings suggest that LV geometry assessment can help improve the stratification of individuals with these CCTA findings.


Subject(s)
Coronary Artery Disease/physiopathology , Hypertrophy, Left Ventricular/physiopathology , Ventricular Function, Left , Ventricular Remodeling , Aged , Computed Tomography Angiography , Coronary Angiography , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/mortality , Echocardiography , Female , Humans , Hypertrophy, Left Ventricular/diagnostic imaging , Hypertrophy, Left Ventricular/mortality , Male , Middle Aged , Multidetector Computed Tomography , Prognosis , Retrospective Studies , Risk Assessment , Risk Factors , Seoul , Time Factors
12.
J Nanosci Nanotechnol ; 21(4): 2234-2245, 2021 04 01.
Article in English | MEDLINE | ID: mdl-33500038

ABSTRACT

Herein, we report the utilization of kitchen waste biomass as a source of carbonaceous material for carbon nanodots synthesis and its application as a plant growth regulator in agricultural crops. The water soluble carbon dots (CDs) were synthesized by pyrolysis of kitchen derived waste tea residue (WTR) and used in the field of agriculture nanotechnology. Herein, we have explored the effect of different concentrations of WTR-CDs (10, 30 and 50 mg/L) on growth of FG with respect to various plant growth parameters. It was observed that the WTR-CDs has positive effect on all plant growth parameters investigated and also assist for micronutrient uptake which is confirmed by AAS and zeta potential measurement. UV light, Fluorescence spectroscopy, and confocal fluorescence microscopy examination were employed for the understanding of uptake and transport route of WTR-CDs in FG plant through absorption of WTR-CDs by root as well as seed coat along with water. Therefore, the growth of FG was a significant increase in quality of the plant which appears to be effective and no serious side effects were seen during the study.


Subject(s)
Carbon , Trigonella , Biomass , Microscopy, Fluorescence , Spectrometry, Fluorescence
13.
Eur Heart J Cardiovasc Imaging ; 22(4): 459-469, 2021 03 22.
Article in English | MEDLINE | ID: mdl-32533163

ABSTRACT

AIMS: We aimed to analyse the time-serial change of cardiac function in light-chain (AL) cardiac amyloidosis patients undergoing active chemotherapy and its relationship with patient outcome. METHODS AND RESULTS: Seventy-two patients with AL cardiac amyloidosis undergoing active chemotherapy who had two or more echocardiographic examinations were identified from a prospective observational cohort (n = 34) and a retrospective cohort (n = 38). Echocardiographic parameters were obtained immediately prior to 1-3, 3-6, 6-12, and 12-24 months after the first chemotherapy. Study endpoint was a composite of death or heart transplantation (HT). During a median of 32 months (interquartile range 8-51) follow-up, 33 patients (45.8%) died and 4 patients (5.6%) underwent HT. Echocardiograms immediately prior to the first chemotherapy did not show differences between the patients with adverse events vs. those without. Significant increase in mitral E/e' ratio and decline in left ventricular global longitudinal strain (LV-GLS) was observed, starting at 3-6 months after the first chemotherapy only in those who experienced adverse events on follow-up, which was also evident in those who responded to chemotherapy. Multivariate analysis demonstrated that B-natriuretic peptide >500 pg/mL and troponin I >0.15 ng/dL at initial diagnosis, hospitalization for heart failure, E/e' >15, and LV-GLS <10% during follow-up were independent predictors of outcome. CONCLUSIONS: In AL cardiac amyloidosis patients undergoing active chemotherapy, the deterioration of LV function may occur, starting even at 3-6 months after the first chemotherapy. Serial echocardiography may help identify those who experience a clinical event in the near future despite active chemotherapy.


Subject(s)
Amyloidosis , Cardiomyopathies , Immunoglobulin Light-chain Amyloidosis , Amyloidosis/diagnostic imaging , Amyloidosis/drug therapy , Follow-Up Studies , Humans , Immunoglobulin Light-chain Amyloidosis/drug therapy , Prognosis , Retrospective Studies
14.
Korean J Intern Med ; 36(2): 332-341, 2021 03.
Article in English | MEDLINE | ID: mdl-31408927

ABSTRACT

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. CONCLUSION: 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.


Subject(s)
Aortic Valve Stenosis , Heart Valve Diseases , Transcatheter Aortic Valve Replacement , Aged , Aged, 80 and over , Aortic Valve/diagnostic imaging , Aortic Valve/surgery , Aortic Valve Stenosis/diagnostic imaging , Aortic Valve Stenosis/etiology , Aortic Valve Stenosis/surgery , Heart Valve Diseases/surgery , Humans , Male , Retrospective Studies , Seoul , Transcatheter Aortic Valve Replacement/adverse effects
15.
Circ J ; 85(7): 1050-1058, 2021 06 25.
Article in English | MEDLINE | ID: mdl-33208592

ABSTRACT

BACKGROUND: The aortic valve area index (AVAI) in aortic stenosis (AS) is measured by echocardiography with a continuity equation using the stroke volume index by Doppler (SVIDoppler) or biplane Simpson (SVIBiplane) method. AVAIDopplerand AVAIBiplaneoften show discrepancy due to differences between SVIDopplerand SVIBiplane. The degree of discrepancy and utility of combined AVAIs have not been investigated in a large population of AS patients, and the characteristics of subjects with larger discrepancies are unknown.Methods and Results:We studied 820 patients with significant AS (AVADoppler<1.5 cm2) enrolled in the Asian Valve Registry, a prospective multicenter registry at 12 Asian centers. All-cause death and aortic valve replacement were defined as events. SVIDopplerwas significantly larger than SVIBiplane(49±11 vs. 39±11 mL/m2, P<0.01) and AVAIDopplerwas larger than AVAIBiplane(0.51±0.15 vs. 0.41±0.14 cm2/m2, P<0.01). An increase in (AVAIDoppler- AVAIBiplane) correlated with shorter height, lower weight, older age, smaller left ventricular (LV) diameter and increased velocity of ejection flow at the LV outflow tract. Severe AS by AVAIDoppleror AVAIBiplaneenabled prediction of events, and combining these AVAIs improved the predictive value of each. CONCLUSIONS: Discrepancy in AVAI by Doppler vs. biplane method was significantly more pronounced with increased LV outflow tract flow velocity, shorter height, lower weight, older age and smaller LV cavity dimensions. Combining the AVAIs enabled mutual and incremental value in predicting events.


Subject(s)
Aortic Valve Stenosis , Aortic Valve , Aortic Valve/diagnostic imaging , Aortic Valve/surgery , Aortic Valve Stenosis/diagnostic imaging , Aortic Valve Stenosis/surgery , Humans , Prospective Studies , Registries , Severity of Illness Index , Stroke Volume , Ventricular Function, Left
16.
JACC Cardiovasc Imaging ; 13(12): 2561-2572, 2020 12.
Article in English | MEDLINE | ID: mdl-32828787

ABSTRACT

OBJECTIVES: The aim of this study was to investigate the relationship between extracellular volume fraction (ECV), a noninvasive parameter that quantifies the degree of diffuse myocardial fibrosis on cardiac magnetic resonance (CMR), and left ventricular diastolic dysfunction (LVDD) in patients with aortic stenosis (AS). BACKGROUND: Myocardial fibrosis on invasive myocardial biopsy is associated with LVDD. However, there is a paucity of data on the association between noninvasively quantified diffuse myocardial fibrosis and the degree of LVDD and how these are related to symptoms and long-term prognosis in patients with AS. METHODS: Patients with moderate or severe AS (n = 191; mean age 68.4 years) and 30 control subjects without cardiovascular risk factors underwent CMR. LVDD grade was evaluated using echocardiography according to the 2016 American Society of Echocardiography/European Association of Cardiovascular Imaging guidelines. Clinical outcomes were defined as a composite of all-cause mortality or hospitalization for heart failure aggravation. RESULTS: Patients in higher ECV quintiles had a significantly higher prevalence of LVDD. Higher ECV was particularly associated with decreased myocardial relaxation (septal e' <7 cm/s) and increased LV filling pressure (E/e' ratio ≥15). Although both impaired diastolic function and higher ECV were significantly associated with a worse degree of dyspnea, patients with higher ECV showed greater dyspnea within the same grade of LVDD. During a median follow-up period of 5.6 years, 37 clinical events occurred. Increased ECV, as well as lower septal e' and higher E/septal e' ratio, were independent predictors of clinical events, irrespective of age, AS severity, aortic valve replacement, and left ventricular (LV) ejection fraction. ECV provided incremental prognostic value on top of clinical factors and LV systolic and diastolic function. CONCLUSIONS: Diffuse myocardial fibrosis, assessed using ECV on CMR, was associated with LVDD in patients with AS, but both ECV and LV diastolic function parameters provided a complementary explanation for dyspnea and clinical outcomes. Concomitant assessment of both LVDD and diffuse myocardial fibrosis may further identify patients with AS with greater symptoms and worse prognosis.


Subject(s)
Aortic Valve Stenosis , Cardiomyopathies , Aged , Aortic Valve Stenosis/pathology , Cardiomyopathies/pathology , Fibrosis , Humans , Magnetic Resonance Imaging, Cine , Myocardium/pathology , Predictive Value of Tests , Stroke Volume , Ventricular Function, Left
17.
Nano Lett ; 20(7): 5376-5382, 2020 Jul 08.
Article in English | MEDLINE | ID: mdl-32525687

ABSTRACT

Charge neutral, nonconjugated organic radicals have emerged as extremely useful active materials for solid-state electronic applications. This previous achievement confirmed the potential of radical-based macromolecules in organic electronic devices; however, charge transport in radical molecules has not been studied in great detail from a fundamental perspective. Here we demonstrate the charge transport in a nonconjugated organic small radical, 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl (h-TEMPO). The chemical component of this radical molecule allows us to form a single crystal via physical vapor deposition (PVD). While the charge transport of this macroscopic open-shell single crystal is rather low, thermal annealing of the well-defined single crystal enables the molecule to have a rapid charge transfer reaction due to the electronic communication of open-shell sites with each other, which results in electrical conductivities greater than 0.05 S m-1. This effort demonstrates a drastically different model than the commonly accepted conjugated polymers or molecules for the creation of next-generation conductors.

19.
Circ Cardiovasc Imaging ; 13(5): e009707, 2020 05.
Article in English | MEDLINE | ID: mdl-32418453

ABSTRACT

BACKGROUND: There is a lack of studies investigating the heterogeneity of patients with aortic stenosis (AS). We explored whether cluster analysis identifies distinct subgroups with different prognostic significances in AS. METHODS: Newly diagnosed patients with moderate or severe AS were prospectively enrolled between 2013 and 2016 (n=398, mean 71 years, 55% male). Among demographics, laboratory, and echocardiography parameters (n=32), 11 variables were selected through dimension reduction and used for unsupervised clustering. Phenotypes and causes of mortality were compared between the clusters. RESULTS: Three clusters with markedly different features were identified. Cluster 1 (n=60) was predominantly associated with cardiac dysfunction, cluster 2 (n=86) consisted of elderly with comorbidities, especially end-stage renal disease, whereas cluster 3 (n=252) demonstrated neither cardiac dysfunction nor comorbidities. Although AS severity did not differ, there was a significant difference in adverse outcomes between the clusters during a median 2.4 years follow-up (mortality rate, 13.3% versus 19.8% versus 6.0% for cluster 1, 2, and 3, P<0.001). Particularly, compared with cluster 3, cluster 1 was associated with only cardiac mortality (adjusted hazard ratio, 7.37 [95% CI, 2.00-27.13]; P=0.003), whereas cluster 2 was associated with higher noncardiac mortality (adjusted hazard ratio, 3.35 [95% CI, 1.26-8.90]; P=0.015). Phenotypes and association of clusters with specific outcomes were reproduced in an independent validation cohort (n=262). CONCLUSIONS: Unsupervised cluster analysis of patients with AS revealed 3 distinct groups with different causes of death. This provides a new perspective in the categorization of patients with AS that takes into account comorbidities and extravalvular cardiac dysfunction.


Subject(s)
Aortic Valve Stenosis/diagnostic imaging , Aortic Valve/diagnostic imaging , Decision Support Techniques , Echocardiography , Unsupervised Machine Learning , Age Factors , Aged , Aged, 80 and over , Aortic Valve/physiopathology , Aortic Valve Stenosis/mortality , Aortic Valve Stenosis/physiopathology , Aortic Valve Stenosis/therapy , Cause of Death , Cluster Analysis , Comorbidity , Female , Hemodynamics , Humans , Male , Middle Aged , Phenotype , Predictive Value of Tests , Prognosis , Prospective Studies , Reproducibility of Results , Risk Factors , Severity of Illness Index
20.
Cardiovasc Diabetol ; 19(1): 69, 2020 05 28.
Article in English | MEDLINE | ID: mdl-32466760

ABSTRACT

BACKGROUND: The effects of sodium-glucose cotransporter 2 inhibitor (SGLT2i) on cardiac function are not fully understood. We investigated the changes in cardiac function in diabetic patients according to the presence and types of heart failure (HF). METHODS: We retrospectively identified 202 diabetic patients who underwent echocardiography before, and 6 to 24 months after the initiation of SGLT2i. After propensity score matching with diabetic patients without SGLT2i, the study population (n = 304) were categorized into group 1 (without HF nor SGLT2i; n = 76), group 2 (without HF and received SGLT2i; n = 78), group 3 (with HF but without SGLT2i; n = 76), and group 4 (with HF and received SGLT2i; n = 74). Changes in echocardiographic parameters were compared between these 4 groups, and between HF patients with reduced versus preserved ejection fraction (EF). RESULTS: After a median 13 months of follow-up, HF patients with SGLT2i showed a significant decrease in left ventricular end-diastolic dimension (LV-EDD; from 57.4 mm [50.0-64.9] to 53.0 mm [48.0-60.0]; p < 0.001) and improvement in LV-EF (from 36.1% [25.6-47.5] to 45.0% [34.8-56.3]; p < 0.001). LV mass index and diastolic parameters also showed improvements in HF patients with SGLT2i. The SGLT2i-induced improvements in cardiac function were more prominent in HF patients than those without HF, and in HFrEF patients than HFpEF patients. CONCLUSIONS: Use of SGLT2i improved cardiac function in diabetic patients, regardless of the presence of HF. The improvements were more prominent in HF patients, especially in those with HFrEF. These improvements in cardiac function would contribute to the clinical benefit of SGLT2i.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Heart Failure/drug therapy , Sodium-Glucose Transporter 2 Inhibitors/therapeutic use , Stroke Volume/drug effects , Ventricular Function, Left/drug effects , Aged , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/diagnosis , Female , Heart Failure/diagnostic imaging , Heart Failure/physiopathology , Humans , Male , Middle Aged , Recovery of Function , Retrospective Studies , Sodium-Glucose Transporter 2 Inhibitors/adverse effects , Time Factors , Treatment Outcome
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