Impact of Drug-Coated Balloon-Based Revascularization in Patients with Chronic Total Occlusions.

Background: Percutaneous coronary intervention (PCI) with a drug-eluting stent (DES) for chronic total coronary occlusions (CTOs) improves clinical symptoms and quality of life. However, data on drug-coated balloon (DCB)-based PCI in CTO lesions are limited. Methods: A total of 200 patients were successfully treated for CTO lesions, either with DCB alone or in combination with DES (DCB-based PCI). They were compared with 661 patients who underwent second-generation DES implantation for CTO from the PTRG-DES registry (DES-only PCI). The endpoint was major adverse cardiovascular events (MACEs), which included a composite of cardiac death, myocardial infarction, stent or target lesion thrombosis, target vessel revascularization, and major bleeding at 2 years. Results: In the DCB-based PCI group, 49.0% of patients were treated with DCB only and 51.0% underwent the hybrid approach combining DCB with DES. Bailout stenting was performed in seven patients (3.5%). The DCB-based PCI group exhibited fewer stents (1.0; IQR: 0.0-1.0 and 2.0; IQR: 1.0-3.0, p < 0.001), shorter stent lengths (6.5 mm; IQR: 0.0-38.0 mm and 42.0 mm; IQR: 28.0-67.0 mm, p < 0.001), and lower usage of small stents with a diameter of 2.5 mm or less (9.8% and 36.5%, p < 0.001). Moreover, the DCB-based PCI group had a lower rate of MACEs than the DES-only PCI group (3.1% and 13.2%, p = 0.001) at 2-year follow-up. Conclusions: The DCB-based PCI approach significantly reduced the stent burden, particularly in the usage of small stent diameters, and resulted in a lower risk of MACEs compared to DES-only PCI in CTO lesions.

Comparison of angiographic change in side-branch ostium after drug-coated balloon vs. drug-eluting stent vs. medication for the treatment of de novo coronary bifurcation lesions.

OBJECTIVES: Data on side-branch (SB) ostial effect after drug-coated balloon (DCB) treatment in the context of de novo coronary bifurcation lesions are limited. We aimed to investigate the angiographic outcomes of SB ostium after DCB treatment compared with drug-eluting stents (DESs) implantation in the main vessel (MV) or optimal medical therapy (OMT) for the treatment of de novo coronary bifurcation lesions. METHODS: Serial angiographic changes in the SB ostium were compared between DCB, DES, and medication alone for MV treatment. Δ value was calculated by subtracting the follow-up value from the pre-procedure value. RESULTS: A total of 132 bifurcation lesions were included for analysis (44 lesions in DCB group; 38 lesions in DES group; 50 lesions in OMT group). The minimal lumen diameter (MLD) of SB ostium showed an increase at follow-up in the DCB group, whereas a decrease was observed in both the DES and OMT groups (ΔMLD: -0.16 ± 0.45 mm for DCB group vs. 0.50 ± 0.52 mm for DES group vs. 0.08 ± 0.38 mm for OMT group, p < 0.001). The diameter stenosis (DS) of SB ostium showed a marked decrease at follow-up in the DCB group, in contrast to an increase observed in both the DES and OMT groups (ΔDS: 8.01 ± 18.96% for DCB group vs. -18.68 ± 18.60% for DES group vs. -2.05 ± 14.58% for OMT group, p < 0.001). CONCLUSIONS: In de novo coronary bifurcation lesions, DCB treatment on the MV demonstrated favorable angiographic outcomes in the SB ostium at 6-9 month follow-up compared to DES implantation or OMT.

Feasibility and safety of non-contrast optical coherence tomography imaging using hydroxyethyl starch in coronary arteries.

Intracoronary optical coherence tomography (OCT) requires injection of flushing media for image acquisition. Alternative flushing media needs to be investigated to reduce the risk of contrast-induced renal dysfunction. We investigated the feasibility and safety of pentastarch (hydroxyethyl starch) for clinical OCT imaging. We prospectively enrolled 43 patients with 70 coronary lesions (46-stented; 24-native). Total 81 OCT pullback pairs were obtained by manual injection of iodine contrast, followed by pentastarch. Each pullback was assessed frame-by-frame using an automated customized lumen contour/stent strut segmentation algorithm. Paired images were compared for the clear image segments (CIS), blood-flushing capability, and quantitative morphometric measurements. Overall image quality, as assessed by the proportion of CIS, was comparable between the contrast- and pentastarch-flushed images (97.1% vs. 96.5%; p = 0.160). The pixel-based blood-flushing capability was similar between the groups (0.951 [0.947-0.953] vs. 0.950 [0.948-0.952], p = 0.125). Quantitative two- and three-dimensional morphometric measurements of the paired images correlated well (p < 0.001) with excellent inter-measurement variability. All patients safely underwent OCT imaging using pentastarch without resulting in clinically relevant complications or renal deterioration. Non-contrast OCT imaging using pentastarch is clinically safe and technically feasible with excellent image quality and could be a promising alternative strategy for patients at high risk of renal impairment.

Label-Free Characterization of Atherosclerotic Plaques Via High-Resolution Multispectral Fluorescence Lifetime Imaging Microscopy.

BACKGROUND: Autofluorescence lifetime (AFL) imaging, a robust technique that enables label-free molecular investigation of biological tissues, is being introduced into the field of cardiovascular diagnostics. However, detailed AFL characteristics of coronary arteries remain elusive and there is a lack of methodology enabling such characterization. METHODS: We developed multispectral fluorescence lifetime imaging microscopy (FLIM) based on analog-mean-delay. Freshly sectioned coronary arteries and atheromas, harvested from 5 swine models, were imaged using FLIM and stained to label lipids, macrophages, collagen, and smooth muscle cells. The components were quantitated from digitized histological images and compared with the corresponding FLIM. Multispectral AFL parameters derived from 2 different spectral bands (390 nm and 450 nm) were analyzed. RESULTS: FLIM provided a wide field-of-view, high-resolution AFL imaging of frozen sections. Principal compositions of coronary arteries, such as tunica media, tunica adventitia, elastic laminas, smooth muscle cell-enriched fibrous plaque, lipid-rich core, and foamy macrophages, were well visualized in FLIM images and were found to have each different AFL spectra. In particular, proatherogenic components including lipids and foamy macrophages exhibited significantly different AFL values compared with plaque-stabilizing collagen- or smooth muscle cell-enriched tissues (P<0.0001). Pairwise comparisons showed that each composition was distinguishable from another by the difference in multispectral AFL parameters. Pixel-level analysis based on coregistered FLIM-histology dataset showed that each component of atherosclerosis (lipids, macrophages, collagen, and smooth muscle cells) had distinct correlation pattern with AFL parameters. Random forest regressors trained with the dataset allowed automated, simultaneous visualization of the key atherosclerotic components with high accuracy (r>0.87). CONCLUSIONS: FLIM provided detailed pixel-level AFL investigation of the complex composition of coronary artery and atheroma. Our FLIM strategy enabling an automated, comprehensive visualization of multiple plaque components from unlabeled sections will be highly useful to efficiently evaluate ex vivo samples without the need for histological staining and analysis.

Drug-coated balloon-based versus drug-eluting stent-only revascularization in patients with diabetes and multivessel coronary artery disease.

BACKGROUND: Data on drug-coated balloon (DCB) treatment in the context of diabetes mellitus (DM) and multivessel coronary artery disease (CAD) are limited. We aimed to investigate the clinical impact of DCB-based revascularization on percutaneous coronary intervention (PCI) in patients with DM and multivessel CAD. METHODS: A total of 254 patients with multivessel disease (104 patients with DM) successfully treated with DCB alone or combined with drug-eluting stent (DES) were retrospectively enrolled (DCB-based group) and compared with 254 propensity-matched patients treated with second-generation DES from the PTRG-DES registry (n = 13,160 patients) (DES-only group). Major adverse cardiovascular events (MACE) comprised cardiac death, myocardial infarction, stroke, stent or target lesion thrombosis, target vessel revascularization, and major bleeding at 2 years. RESULTS: The DCB-based group was associated with a reduced risk of MACE in patients with DM (hazard ratio [HR] 0.19, 95% confidence interval [CI] 0.05-0.68, p = 0.003], but not in those without DM (HR 0.52, 95% CI 0.20-1.38, p = 0.167) at the 2-year follow-up. In patients with DM, the risk of cardiac death was lower in the DCB-based group than the DES-only group, but not in those without DM. In both patients with or without DM, the burdens of DES and small DES (less than 2.5 mm) used were lower in the DCB-based group than in the DES-only group. CONCLUSIONS: In multivessel CAD, the clinical benefit of a DCB-based revascularization strategy appears to be more evident in patients with DM than in those without DM after 2 years of follow-up. (Impact of Drug-Coated Balloon Treatment in De Novo Coronary Lesion; NCT04619277).

Fifteen-Year Nationwide Trend in Antiplatelet Treatment among Drug-Eluting Stent Recipients in Korea: Many Patients Receive Very Prolonged Dual-Antiplatelet Treatment, and Newer Drugs Are Replacing the Older Ones.

Drug-eluting stent (DES) recipients require 6-12 months of dual antiplatelet treatment (DAPT) and long-term aspirin mono-antiplatelet treatment (MAPT). Given the diversity of contemporary antiplatelet agents, antiplatelet treatment (APT) selection is becoming more complicated. We evaluated 15-year APT trends based on nationwide prescription data of 79,654 patients who underwent percutaneous coronary intervention (PCI) using DESs from 2002 to 2018 in Korea. DAPT (80.7%) was the most preferred initial APT post-PCI. Many DES recipients received prolonged DAPT (post-PCI 3 years: 41.0%; 10 years: 27.7%). There was a noticeable delay in DAPT-to-MAPT conversion from the mid to late 2000s (after the late-stent thrombosis concerns of first-generation DESs raised); the conversion after that was similar during the 2010s, occurring most robustly at 12-18 months post-PCI. Clopidogrel had long and increasingly been used for MAPT, surpassing aspirin. The recent increase in newer P2Y12 inhibitor prescriptions was noted. The patients treated with newer P2Y12 inhibitors were more likely younger men and presented with acute myocardial infarction. Real-world APT is evolving, and guideline-practice gaps exist. Further studies exploring the impact of diverse APT strategies on patient outcomes are expected to provide insights into optimal APT that can sophisticatedly balance the ischemic and bleeding risks.

Clinical Impact of Drug-Coated Balloon-Based Percutaneous Coronary Intervention in Patients With Multivessel Coronary Artery Disease.

BACKGROUND: Data on drug-coated balloon (DCB) treatment in the context of multivessel coronary artery disease (CAD) are limited. OBJECTIVES: The purpose of this study was to investigate the impact of DCB-based treatment on percutaneous coronary intervention for multivessel CAD. METHODS: A total of 254 patients with multivessel disease successfully treated with DCBs or in combination with drug-eluting stents (DES) were retrospectively enrolled (DCB-based group) and compared with 254 propensity-matched patients treated with second-generation DES from the PTRG-DES (Platelet Function and Genotype-Related Long-Term Prognosis in Drug-Eluting Stent-Treated Patients With Coronary Artery Disease) registry (n = 13,160) (DES-only group). Major adverse cardiovascular events (MACE) comprised cardiac death, myocardial infarction, stroke, stent thrombosis, target vessel revascularization, and major bleeding at 2 years. RESULTS: Baseline clinical characteristics were comparable between the groups. In the DCB-based group, 34.3% of patients were treated with DCBs only and 65.7% were treated with the DES hybrid approach. The number of stents and total stent length were significantly reduced by 65.4% and 63.7%, respectively, in the DCB-based group compared with the DES-only group. Moreover, the DCB-based group had a lower rate of MACE than the DES-only group (3.9% and 11.0%; P = 0.002) at 2-year follow-up. The DES-only group had a higher risk for cardiac death and major bleeding. CONCLUSIONS: The DCB-based treatment approach showed a significantly reduced stent burden for multivessel percutaneous coronary intervention and led to a lower rate of MACE than the DES-only treatment. This study shows that DCB-based treatment approach safely reduces stent burden in multivessel CAD, and improved long-term outcomes may be expected by reducing stent-related events. (Impact of Drug-Coated Balloon Treatment in De Novo Coronary Lesion; NCT04619277).

Prevalence of Isolated Nocturnal Hypertension and Development of Arterial Stiffness, Left Ventricular Hypertrophy, and Silent Cerebrovascular Lesions: The KoGES (Korean Genome and Epidemiology Study).

Background Apart from nondippers' impact on cardiovascular events, the prevalence of isolated nocturnal hypertension (INH) and its consequences on both the heart and brain were not clearly investigated in the general population. Methods and Results The participants underwent ambulatory blood pressure monitoring evaluations for arterial stiffness, echocardiography, and brain magnetic resonance imaging. They were grouped into normotension, INH, and overt diurnal hypertension, based on ambulatory blood pressure monitoring and history of antihypertensive treatment. White matter hyperintensity, arterial stiffness, and echocardiographic parameters were compared. Of the 1734 participants, there were 475 (27.4%) subjects with normotension, 314 with INH (18.1%), and 945 with overt diurnal hypertension (54.5%). Prevalence of INH was not different between sex or age. Of INH, 71.3% (n=224) was caused by elevated diastolic blood pressure. After multivariable adjustment, INH showed higher pulse wave velocity (P<0.001) and central systolic blood pressure (P<0.001), left ventricular mass index (P=0.026), and worse left ventricular diastolic function (early diastolic mitral annular velocity) (P<0.001) than normotension. Mean white matter hyperintensity scores of INH were not different from normotension (P=0.321), but the odds for white matter hyperintensity presence were higher in INH than normotension (odds ratio, 1.504 [95% CI, 1.097-2.062]; P=0.011). Conclusions INH was common in the general population and associated with increased arterial stiffness, left ventricular hypertrophy, and diastolic dysfunction. White matter hyperintensity was more likely to be present in the INH group than in the normotension group. The use of ambulatory blood pressure monitoring should be encouraged to identify masked INH and prevent the occurrence of cardiovascular events.

Favorable Vasomotor Function after Drug-Coated Balloon-Only Angioplasty of De Novo Native Coronary Artery Lesions.

Balloon-injured coronary segments are known to harbor abnormal vasomotion. We evaluated whether de novo coronary lesions treated using drug-coated balloon (DCB) are prone to vasospasm and how they respond to ergonovine and nitrate. Among 132 DCB angioplasty recipients followed, 89 patients underwent ergonovine provocation test at 6-9 months follow-up. Within-subject ergonovine- and nitrate-induced diameter changes were compared among three different sites: DCB-treated vs. angiographically normal vs. segment showing prominent vasoreactivity (spastic). No patient experienced clinically refractory vasospastic angina or symptom-driven revascularization during follow-up. Ergonovine induced vasospasm in seven patients; all were multifocal spasm either involving (n = 2) or rather sparing DCB-treated segments (n = 5). None showed focal spasm that exclusively involved DCB-treated lesions. Among 27 patients with vasospastic features, DCB-treated segments showed less vasoconstriction than spastic counterparts (p < 0.001). A total of 110 DCB-treated lesions were analyzed to assess vasomotor function. Vasomotor function, defined as a combined constrictor and dilator response, was comparable between DCB-treated and angiographically normal segments (p = 0.173), while significant differences were observed against spastic counterparts (p < 0.001). In our study, DCB-treated lesions were not particularly vulnerable to vasospasm and were found to have vasomotor function similar to angiographically normal segments, supporting safety of DCB-only strategy in treating de novo native coronary lesions.

Coronary artery aneurysm formation after paclitaxel-coated balloon-only intervention for de novo coronary chronic total occlusion.

Background: Although coronary artery aneurysm (CAA) is an uncommon complication of drug-coated balloon (DCB) treatment, the incidence and mechanisms CAA formation after DCB intervention for chronic total occlusion (CTO) remains to be clarified. The aim of this study was to investigate the incidence of CAA after DCB intervention for the treatment of CTO of coronary arteries. Materials and methods: This was a retrospective analysis of 82 patients, contributing 88 vessels, who underwent successful DCB-only treatment for de novo CTO lesions. Follow-up angiography was performed in all cases, at a mean 208.5 (interquartile range [IQR]: 174.8 to 337.5) days after the index procedure. Results: CAA was identified in seven vessels, in seven patients, at the site of previous successful DCB-only treatment. Of these, six were fusiform in shape and one saccular, with a mean diameter of 4.2 ± 1.0 mm and length of 6.7 ± 2.6 mm. Six CAAs developed at the CTO inlet site, and all CAAs occurred at the lesions following dissection immediately after DCB treatment. CAAs were not associated with an increased risk of major clinical events over the median follow-up of 676.5 (IQR: 393.8 to 1,304.8) days. Conclusion: The incidence of CAA after DCB-only treatment for CTO lesions was 8.0% in this study. Further research is warranted, using intravascular imaging, to clarify the mechanism of DCB-related CAA formation and prognosis.

Macrophage targeted theranostic strategy for accurate detection and rapid stabilization of the inflamed high-risk plaque.

Rationale: Inflammation plays a pivotal role in the pathogenesis of the acute coronary syndrome. Detecting plaques with high inflammatory activity and specifically treating those lesions can be crucial to prevent life-threatening cardiovascular events. Methods: Here, we developed a macrophage mannose receptor (MMR)-targeted theranostic nanodrug (mannose-polyethylene glycol-glycol chitosan-deoxycholic acid-cyanine 7-lobeglitazone; MMR-Lobe-Cy) designed to identify inflammatory activity as well as to deliver peroxisome proliferator-activated gamma (PPARγ) agonist, lobeglitazone, specifically to high-risk plaques based on the high mannose receptor specificity. The MMR-Lobe-Cy was intravenously injected into balloon-injured atheromatous rabbits and serial in vivo optical coherence tomography (OCT)-near-infrared fluorescence (NIRF) structural-molecular imaging was performed. Results: One week after MMR-Lobe-Cy administration, the inflammatory NIRF signals in the plaques notably decreased compared to the baseline whereas the signals in saline controls even increased over time. In accordance with in vivo imaging findings, ex vivo NIRF signals on fluorescence reflectance imaging (FRI) and plaque inflammation by immunostainings significantly decreased compared to oral lobeglitazone group or saline controls. The anti-inflammatory effect of MMR-Lobe-Cy was mediated by inhibition of TLR4/NF-κB pathway. Furthermore, acute resolution of inflammation altered the inflamed plaque into a stable phenotype with less macrophages and collagen-rich matrix. Conclusion: Macrophage targeted PPARγ activator labeled with NIRF rapidly stabilized the inflamed plaques in coronary sized artery, which could be quantitatively assessed using intravascular OCT-NIRF imaging. This novel theranostic approach provides a promising theranostic strategy for high-risk coronary plaques.

Clinical and central hemodynamic characteristics of early adulthood isolated diastolic hypertension: a comparison with isolated systolic hypertension.

OBJECTIVES: Knowledge on early adulthood isolated diastolic hypertension (IDH) is limited. We compared the clinical and central hemodynamic characteristics of early adulthood IDH, isolated systolic hypertension (ISH) and normotension. METHODS: A total of 509 untreated young adults (18-35 years) who underwent ambulatory blood pressure monitoring (ABPM; ABPM cohort), 148 who underwent both ABPM and applanation tonometry (ABPM-tonometry cohort) and 26 newly recruited normotensives were analyzed. Their pulse wave images were analyzed after categorizing them into type A vs. B vs. C. RESULTS: In the ABPM cohort (men, 86.6%), systolic-diastolic hypertension was the most common subtype (68.0%), while IDH was the rarest (5.1%). The subtype composition showed age-dependency; the proportion of IDH and systolic-diastolic hypertension increased across the age tertiles, while that of ISH declined. Patients with IDH were significantly older and shorter than those with ISH. Despite having a significantly lower 24-h average systolic blood pressure (SBP), patients with IDH exhibited discordantly high central systolic blood pressures at levels comparable to those of patients with ISH. Pulse pressure amplification was the lowest in patients with IDH and highest in those with ISH (P < 0.001), accounting for the discordance. Augmentation index differed significantly between them (P < 0.016). The waveform composition differed across the subtypes (type A vs. B/C: IDH = 61.5 vs. 38.5%; ISH = 3.0 vs. 97.0%; normotension = 30.8 vs. 69.2%, P < 0.001); the averaged waveform plots demonstrated a clear morphological disparity between IDH (type A) and ISH (type B/C). CONCLUSIONS: Early adulthood IDH is a unique entity clearly distinguishable from ISH in terms of clinical and central hemodynamic characteristics.

Effect of body mass index and abdominal obesity on mortality after percutaneous coronary intervention: a nationwide, population-based study.

BACKGROUND/AIMS: We investigated the impact of obesity on the clinical outcomes following percutaneous coronary intervention (PCI). METHODS: We included South Koreans aged > 20 years who underwent the Korean National Health Screening assessment between 2009 and 2012. Obesity was defined using the body mass index (BMI), according to the World Health Organization's recommendations. Abdominal obesity was defined using the waist circumference (WC), as defined by the Korean Society for Obesity. The odds and hazard ratios in all-cause mortality were calculated after adjustment for multiple covariates. Patients were followed up to the end of 2017. RESULTS: Among 130,490 subjects who underwent PCI, the mean age negatively correlated with BMI. WC, hypertension, diabetes, dyslipidemia, fasting glucose, total cholesterol, low-density lipoprotein cholesterol, and triglyceride levels correlated with the increased BMI. The mortality rates were higher in the lower BMI and WC groups than the higher BMI and WC groups. The non-obese with abdominal obesity group showed a mortality rate of 2.11 per 1,000 person-years. Obese with no abdominal obesity group had the lowest mortality rate (0.88 per 1,000 person-years). The mortality showed U-shaped curve with a cut-off value of 29 in case of BMI and 78 cm of WC. CONCLUSION: The mortality showed U-shaped curve and the cut-off value of lowest mortality was 29 in case of BMI and 78 cm of WC. The abdominal obesity may be associated with poor prognosis in Korean patients who underwent PCI.

Comprehensive Assessment of High-Risk Plaques by Dual-Modal Imaging Catheter in Coronary Artery.

Coronary plaque destabilization involves alterations in microstructure and biochemical composition; however, no imaging approach allows such comprehensive characterization. Herein, the authors demonstrated a simultaneous microstructural and biochemical assessment of high-risk plaques in the coronary arteries in a beating heart using a fully integrated optical coherence tomography and fluorescence lifetime imaging (FLIm). It was found that plaque components such as lipids, macrophages, lipids+macrophages, and fibrotic tissues had unique fluorescence lifetime signatures that were distinguishable using multispectral FLIm. Because FLIm yielded massive biochemical readouts, the authors incorporated machine learning framework into FLIm, and ultimately, their approach enabled an automated, quantitative imaging of multiple key components relevant for plaque destabilization.

Flexible endoscopic micro-optical coherence tomography for three-dimensional imaging of the arterial microstructure.

Micro-optical coherence tomography (µOCT) is a novel imaging approach enabling visualization of the microstructures of biological tissues at a cellular or sub-cellular level. However, it has been challenging to develop a miniaturized flexible endoscopic µOCT probe allowing helical luminal scanning. In this study, we built a flexible endoscopic µOCT probe with an outer diameter of 1.2 mm, which acquires three-dimensional images of the arterial microstructures via helical scanning with an axial and lateral resolutions of 1.83 µm and 3.38 µm in air, respectively. Furthermore, the depth of focus of the µOCT imaging probe was extended two-fold using a binary phase spatial filter. We demonstrated that the present endoscopic µOCT could image cellular level features of a rabbit artery with high-risk atheroma and a bioresorbable scaffold-implanted swine coronary artery. This highly-translatable endoscopic µOCT will be a useful tool for investigating coronary artery disease and stent biology.

Pulmonary Vein Enlargement as an Independent Predictor for New-Onset Atrial Fibrillation.

Pulmonary vein (PV) enlargement is associated with atrial fibrillation (AF). However, the predictive value of PV volume for new-onset AF has not been determined. We retrospectively assessed and enrolled non-AF subjects who underwent echocardiography and cardiac CT angiography (CCTA) around the same time and evaluated the development of AF longitudinally. PV volume was assessed by estimating the three-dimensional CCTA-derived mid-diastolic PV volume from the ostium to tertiary branches. Overall, 1105 subjects were enrolled. Among them, 29 developed AF during a mean follow-up of 4.28 ± 3.08 years after baseline CCTA and echocardiography. The AF group had a higher proportion of older aged subjects, a higher ratio of early mitral flow velocity (E) to early mitral annular tissue velocity (Em), higher Em, and larger left atrial (LAVI) and PV (PVVI) volume indices. PVVI was independently associated with male sex, left ventricular dimension, E/Em and LAVI. AF incidence increased markedly across each baseline PVVI tertile (2.2%, 5.1%, and 10.8%). In the multivariate Cox model, increased PVVI was independently associated with new-onset AF (hazard ratio (HR) = 5.401, 4.931-6.193, p = 0.007). Based on the analysis of multimodal cardiac imaging, our results provide mechanistic insights into PV remodeling and its potential role as a link between diastolic dysfunction and developing AF.

Central hemodynamic characteristics of young adults with isolated systolic hypertension: an ambulatory blood pressure monitoring-based study of real-world clinical patients.

The central hemodynamic characteristics of young adults with isolated systolic hypertension (ISH) remain controversial, particularly regarding the extent of pulse pressure amplification (PPamp) compared with that of normotensives (NTs). Given the lack of ambulatory blood pressure monitoring (ABPM)-based data, this study evaluated 509 untreated young adults (18-35 years) who had undergone ABPM during the last decade, 109 who had undergone both ABPM and SphygmoCor analysis, and 26 newly recruited NTs. The agreement rate between office BP- and ABPM-based subtype classification was alarmingly low (50.7%). ISH was distinguishable from systolic-diastolic hypertension, the predominant subtype characterized by increased central BPs and stiffened arteries. The central hemodynamic parameters were all similar between patients with ISH and white-coat hypertension (WC). ISH patients had central BPs that were, albeit higher than those of NTs, at an upper-normal level that was comparable to those of WC patients. ISH patients had similar cfPWV but significantly higher PPamp than NTs (p = 0.032). The central hemodynamic parameters of the participants were further analyzed according to central pressure waveform types (A vs. B vs. C). Type C waves were associated with the highest PPamp and lowest cfPWV, whereas type A waves were associated with the lowest PPamp and highest cfPWV. Subjects with type B waves, an intermediate form, also had considerably high PPamps. Waveform composition differed significantly across hypertension subtypes (p < 0.001). ISH patients mostly had type B or C waves (96.7%), with only 3.3% having type A waves. This study based on a refined diagnosis showed that the ambulatory ISH of young adults arises from highly elastic arteries and related robustness of PPamp and shares similar central hemodynamic characteristics with WC patients.

Effect of applied voltage and temperature on methane production and microbial community in microbial electrochemical anaerobic digestion systems treating swine manure.

Microbial electrochemical technology (MET) that can harvest electricity/valuable materials and enhance the efficiency of conventional biological processes through the redox reaction of organic/inorganic compounds has attracted considerable attention. MET-based anaerobic digestion (AD) systems treating swine manure were operated at different applied voltages (0.1, 0.3, 0.5, 0.7, and 0.9 V) and temperatures (25, 35, and 45 °C). Among the MET-based AD systems with different applied voltages at 35 °C, M4 at 0.7 V showed the highest methane production (2.96 m3-CH4/m3) and methane yield (0.64 m3-CH4/kg-VS). The methane production and yield increased with increasing temperature at an applied voltage of 0.7 V. Nevertheless, the MET-based AD systems (LM at 25 °C and 0.7V) showed competitive AD performance (2.33 m3-CH4/m3 and 0.53 m3-CH4/VS) compared with the conventional AD system (35 °C). The microbial community was affected by the applied voltage and temperature, and hydrogenotrophic methanogens such as M. flavescens, M. hungatei, and M. thermautotrophicus were mainly responsible for methane production in MET-based AD systems. Therefore, the methane production can be enhanced by an applied voltage or by direct interspecies electron transfer because M. flavescens and M. thermautotrophicus were especially predominant in cathode of MET-based AD systems. The MET-based AD systems can help enhance biogas production from swine manure with no significant change in methane content. Furthermore, MET-based AD systems will be a promising AD system through low material development and the optimal operation.