Association of exosomes in patients with compromised myocardial perfusion on functional imaging.

OBJECTIVES: Exosomes are membrane vesicles that are actively secreted in response to microenvironmental stimuli. In this study, we quantified the amount of exosomes in patients with significant coronary artery disease (CAD) and evaluated its relationship with myocardial perfusion imaging (MPI) results. METHODS: Patients who underwent both MPI and coronary angiography were recruited. Plasma was collected during angiography, and exosomes were extracted via the precipitation method. The summed stress scores (SSS), summed difference scores, and ventricular functional parameters were calculated from the MPI and compared with the amounts of exosomes and extracted miRNAs. RESULTS: In total, 115 patients were enrolled (males: 78 %; mean age: 66.6 ± 10.6 years). Those with abnormal SSS according to the MPI had significantly fewer exosomes (p = 0.032). After multivariate analysis, the SSS remained significantly related to the amount of exosomes (p = 0.035). In forty randomly selected samples, miRNA-432-5p and miRNA-382-3p were upregulated in patients with abnormal SSS. CONCLUSIONS: Patients with compromised poststress myocardial perfusion on MPI tended to have fewer exosomes in association with CAD-related miRNAs. This is the first study to clarify the fundamental and pathophysiological causes of CAD using radiographic examinations.

Long-term outcomes of left atrial appendage occlusion in patients with atrial fibrillation and end stage renal disease.

OBJECTIVE: In patients with atrial fibrillation (AF) and end-stage renal disease (ESRD), oral anticoagulants are contraindicated, and left atrial appendage occlusion (LAAO) is an alternative treatment. However, the efficacy of thromboembolic prevention using LAAO in these patients has rarely been reported in Asian populations. To our knowledge, this is the first long-term LAAO study in patients with AF undergoing dialysis in Asia. METHODS: In this study, 310 patients (179 men) with a mean age of 71.3 ± 9.6 years and mean CHA2DS2-VASc 4.2 ± 1.8 were consecutively enrolled at multiple centers in Taiwan. The outcomes of 29 patients with AF and ESRD undergoing dialysis who underwent LAAO were compared to those without ESRD. The primary composite outcomes were stroke, systemic embolization, or death. RESULTS: No difference in mean CHADS-VASc score was noted between patients with versus without ESRD (4.1 ± 1.8 vs. 4.6 ± 1.9, p = 0.453). After a mean follow-up of 38 ± 16 months, the composite endpoint was significantly higher in patients with ESRD (hazard ratio, 5.12 [1.4-18.6]; p = 0.013) than in those without ESRD after LAAO therapy. Mortality was also higher in patients with ESRD (hazard ratio, 6.6 [1.1-39.7]; p = 0.038). The stroke rate was numerically higher in patients with versus without ESRD, but the difference was not statistically significant (hazard ratio, 3.2 [0.6-17.7]; p = 0.183). Additionally, ESRD was associated with device-related thrombosis (odds ratio, 6.15; p = 0.047). CONCLUSION: Long-term outcomes of LAAO therapy may be less favorable in patients with AF undergoing dialysis, possibly because of the poor condition of patients with ESRD.

The Identification of Subsequent Events Following Out-of-Hospital Cardiac Arrests with Targeted Temperature Management.

Background: Out-of-hospital cardiac arrest (OHCA) is a critical issue due to poor neurological outcomes and high mortality rate. Severe ischemia and reperfusion injury often occur after cardiopulmonary resuscitation (CPR) and return of spontaneous circulation (ROSC). Targeted temperature management (TTM) has been shown to reduce neurological complications among OHCA survivors. However, it is unclear how "time-to-cool" influences clinical outcomes. In this study, we investigated the optimal timing to reach target temperature after cardiac arrest and ROSC. Methods: A total of 568 adults with OHCA and ROSC were admitted for targeted hypothermia assessment. Several events were predicted, including pneumonia, septic shock, gastrointestinal (GI) bleeding, and death. Results: One hundred and eighteen patients [70 men (59.32%); 48 women (40.68%)] were analyzed for clinical outcomes. The duration of CPR after ROSC was significantly associated with pneumonia, septic shock, GI bleeding, and mortality after TTM (all p < 0.001). The duration of CPR was also positively correlated with poor outcomes on the Elixhauser score (p = 0.001), APACHE II score (p = 0.008), Cerebral Performance Categories (CPC) scale (p < 0.001), and Glasgow Coma Scale (GCS) score (p < 0.001). There was a significant association between the duration of CPR and time-to-cool of TTM after ROSC (Pearson value = 0.447, p = 0.001). Pneumonia, septic shock, GI bleeding, and death were significantly higher in the patients who underwent TTM with a time-to-cool exceeding 360 minutes (all p < 0.001). Conclusions: For cardiac arrest patients, early cooling has clear benefits in reducing clinical sequelae. Clinical outcomes could be improved by improving the time to reach target temperature and feasibility for critically ill patients.

Intraocular pressure-lowering efficacy and ocular safety of Rho-kinase inhibitor in glaucoma: a meta-analysis and systematic review of prospective randomized trials.

PURPOSE: To evaluate the intraocular pressure (IOP)-reducing efficacy and safety of Rho-kinase inhibitor (RKI). METHODS: Published studies in PubMed and EMBASE were searched on March 20, 2021. Study selection and data extraction were performed according to PRISMA. Meta-analysis of the IOP-lowering effect was performed with the bivariate random-effects model, with studies categorized into 2 classes: RKI versus placebo and RKI versus another medication. The main outcome was the difference in IOP reduction between RKI and non-RKI groups. Subgroup analysis of adjunctive RKI efficacy and additional review of its major ocular adverse events (AE) were also performed. RESULTS: Ten (2.6%) out of 391 studies were retrieved. In the RKI versus placebo class, RKI showed greater IOP reduction after 4-8 weeks (mean difference = - 1.69 mmHg [- 2.22, - 1.16], P < 0.001). In the RKI versus another medication class, IOP reduction by RKI was noninferior to timolol 0.5% twice-daily after 4-8 weeks (mean difference = 0.39 mmHg [0.01, 0.76], P = 0.043) and 12 weeks (mean difference = 0.48 mmHg [0.11, 0.85]; P = 0.011). In the subgroup analysis, the mean difference in IOP reduction by adjunctive RKI and placebo was - 1.42 mmHg (P < 0.001). The most common ocular AE of RKI was conjunctival hyperemia (19-65%), followed by conjunctival hemorrhage (6-20%) and cornea verticillata (13-26%). CONCLUSIONS: With a treatment duration of 1-3 months, RKI showed effective IOP reduction noninferior to timolol as monotherapy and as adjunctive therapy. Our results suggested RKI be a reliable IOP control medication; however, its higher incidence of some ocular complications should be attended to.

Sex, racial differences and healthy aging in normative reference ranges on diastolic function in Ethnic Asians: 2016 ASE guideline revisited.

BACKGROUND: Diastolic dysfunction (DD) has shown to be a hallmark pathological intermediate in the development of heart failure with preserved ejection fraction (HFpEF). We aim to establish age- and sex-stratified normal reference values of diastolic indices and to explore racial-differences. METHODS: We explored age- and sex-related structural/functional alterations from 6023 healthy ethnic Asians (47.1 ± 10.9 years, 61.3% men) according to 2016 American Society of Echocardiography (ASE) diastolic dysfunction (DD) criteria. Racial comparisons were made using data from London Life Sciences Prospective Population (LOLIPOP) study. RESULTS: Age- and sex-based normative ranges (including mean, median, 10% and 90% lower and upper reference values) were extracted from our large healthy population. In fully adjusted models, advanced age was independently associated with cardiac structural remodeling and worsened diastolic parameters including larger indexed LA volume (LAVi), lower e', higher E/e', and higher TR velocity; all p < 0.001), which were more prominent in women (P interaction: <0.05). Broadly, markedly lower e', higher E/e' and smaller LAVi were observed in ethnic Asians compared to Whites. DD defined by 2016 ASE criteria, despite at low prevalence (0.42%) in current healthy population, increased drastically with advanced age and performed perfectly in excluding abnormal NT-proBNP (≥125 pg/mL) (Specificity: 99.8%, NPV: 97.6%). CONCLUSION: This is to date the largest cohort exploring the normative reference values using guideline-centered diastolic parameters from healthy Asians, with aging played as central role in diastolic dysfunction. Our observed sex and ethnic differences in defining healthy diastolic cut-offs likely impact future clinical definition for DD in Asians.

Combined intravenous immunoglobulin and baricitinib treatment for severe COVID-19 with rhabdomyolysis: A case report.

Since December 2019, the outbreak of coronavirus disease 2019 (COVID-19) has spread rapidly around the world. The severity of COVID-19 ranges from asymptomatic carriers to severe acute respiratory distress syndrome (ARDS). Accumulating evidence has shown that COVID-19 may be associated with multiple organ complications including cardiac injury, viral myositis and neurological deficits. Numerous laboratory biomarkers including lymphocytes, platelets, lactate dehydrogenase and creatine kinase (CK) have been associated with the prognostic outcomes of patients with COVID-19. However, dynamic correlations between levels of biomarkers and clinical course have not been studied. Herein, we report a 74-year-old female patient with severe COVID-19 which progressed to ARDS requiring intubation and mechanical ventilation. The laboratory findings showed lymphopenia, hypogammaglobulinemia, and elevated inflammatory biomarkers and CK. She received intensive therapy with hydroxychloroquine, lopinavir/ritonavir, and azithromycin with limited effects. Immunomodulatory treatments with high dose intravenous immunoglobulin and baricitinib were prescribed with satisfactory biochemical, radiographic and clinical recovery. We found an interesting correlation between serum CK elevation and inflammatory biomarkers, which reflected clinical improvement. This case demonstrates that inflammatory biomarkers, cytokines, and CK level correlated with disease severity and treatment response, and combined use of intravenous immunoglobulin and baricitinib is a potential treatment in patients with severe COVID-19.

Prevalence of sudden arrhythmic death syndrome-related genetic mutations in an Asian cohort of whole genome sequence.

AIMS: Recently, the spectrum of background mutation in the genes implicated in sudden arrhythmic death syndrome (SADS), has been elucidated in the Caucasian populations. However, this information is largely unknown in the Asian populations. METHODS AND RESULTS: We assessed the background rare variants (minor allele frequency < 0.01) of major SADS genes in whole genome sequence data of 1514 healthy Taiwanese subjects from the Taiwan Biobank. We found up to 45% of healthy subjects have a rare variant in at least one of the major SADS genes. Around 3.44% of healthy subjects had multiple mutations in one or multiple genes. The background mutation rates in long QT syndrome, catecholaminergic polymorphic ventricular tachycardia, and arrhythmogenic right ventricular cardiomyopathy genes were similar, but those in Brugada syndrome (BrS) (SCN5A) and hypertrophic cardiomyopathy (HCM) genes (MYBPC3, MYH7, and TNNT2) were higher, compared to those reported in the Caucasian populations. Furthermore, the rate of incidental pathogenic variant was highest in MYBPC3 gene. Finally, the number of variant was proportional to the exon length of the gene (R2 = 0.486, P = 0.0056) but not related to its functional or evolutionary importance (degree of evolutionary conservation) (R2 = 0.0008, P = 0.9218), suggesting that the mutation was random. The ratio of variant number over exon nucleotide length was highest in MYBPC3, MYH7, and TNNT2 genes. CONCLUSION: Unique features of background SADS gene mutation in the Asian populations include higher prevalence of incidental variant in HCM, BrS, and long QT 3 (SCN5A) genes. HCM genes have the highest variant number per exon length.

The effect and molecular mechanism of statins on the expression of human anti-coagulation genes.

Statins are potent lipid-lowering drugs. Large prospective clinical trials have shown the anti-thrombotic effect of statins, e.g., preventing deep vein thrombosis. However, the mechanism underlying the beneficial effect of statins in reducing thrombus formation remains to be established. We, thus, conduct this study to investigate the potential molecular mechanisms. The cultured human hepatoma cells (HepG2) were used as the in vitro model. The human protein C gene promoter was cloned into the luciferase reporter to study the transcriptional regulation of human protein C gene. Wistar rats fed with simvastatin (5 mg/kg day) were used as the in vivo model. We found that simvastatin increased the expression of protein C in hepatocytes (361 ± 64% and 313 ± 59% after 2 h and 6 h of stimulation, respectively, both p < 0.01). In the animal study, the serum protein C levels were increased in the simvastatin-treated group (7 ± 2.2 unit/ml vs 23.4 ± 19.3 unit/ml and 23.4 ± 18.2 unit/ml and 1 and 2 weeks of treatment, respectively, both p < 0.05). Regarding the possible molecular mechanism, we found that the level of hepatocyte nuclear factor 1α (HNF1α) was also increased in both the in vivo and in vitro models. We found that the protein C promoter activity was increased by simvastatin, and this effect was inhibited by HNF1α knockdown and constitutively active Rac1. Therefore, stains may modulate protein C expression through small GTPase Rac 1 and HNF1α.

The associations among co-morbidity, cardiac geometries and mechanics in hospitalized heart failure with or without preserved ejection fraction.

BACKGROUND: The associations among chronic health conditions, ventricular geometric alterations or cardiac contractile mechanics in different phenotypes heart failure (HF) remain largely unexplored. METHODS: We studied 438 consecutive hospitalized patients (mean age: 64.9 ± 16.6 years, 52.5% female) with or without clinical evidence of HF. We examined the associations among clinical co-morbidities, LV geometries and systolic mechanics in terms of global myocardial strains. RESULTS: Increasing clinical co-morbidities was associated with greater LV mass, worse longitudinal deformations and higher proportion of admission with HF diagnosis, which was more pronounced in HFpEF (from 6.4% to 40.7%, X2 < 0.001). The independent association between co-morbidity burden and longitudinal functional decay remained unchanged after adjusting for age and sex for all admissions and in HFpEF (Coef: 0.82 & 0.71, SE: 0.13 & 0.21, both p≤0.001). By using co-morbidity scores, the area under receiver operating characteristic curves (AUROC) in identifying HFpEF was 0.71 (95% CI: 0.65 to 0.77), 0.64 (95% CI: 0.58 to 0.71) for HFrEF and 0.72 for both (95% CI: 0.67 to 0.77). Co-morbidity burden superimposed on LV mass index and LV filling pressure (E/E') further expanded the AUROC significantly in diagnosing both types HF (c-statistics from 0.73 to 0.81, p for ΔAUROC: 0.0012). CONCLUSION: Chronic health conditions in the admission population were associated with unfavorable cardiac remodeling, impair cardiac contractile mechanics and further added significantly incremental value in HF diagnosis. Our data suggested the potentiality for better cardiac function by controlling baseline co-morbidities in hospitalized HF patients, especially HFpEF. ABBREVIATIONS: CAD: coronary artery disease; CKD: chronic kidney disease; DT: deceleration time; eGFR: Estimated glomerular filtration rate; HF: heart failure; IVRT: iso-volumic relaxation time; LV: left ventricular; LVEF: left ventricular ejection fraction; RWT: relative wall thickness; TDI: Tissue Doppler imaging.

Next-generation sequencing of nine atrial fibrillation candidate genes identified novel de novo mutations in patients with extreme trait of atrial fibrillation.

BACKGROUND: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. Genome-wide association studies (GWAS) have identified common variants in nine genomic regions associated with AF (KCNN3, PRRX1, PITX2, WNT8A, CAV1, C9orf3, SYNE2, HCN4 and ZFHX3 genes); however, the genetic variability of these risk variants does not explain the entire genetic susceptibility to AF. Rare variants missed by GWAS may also contribute to genetic risk of AF. METHODS: We used an extreme trait design to sequence carefully selected probands with extreme phenotypes and their unaffected parents to identify rare de novo variants or mutations. Based on the hypothesis that common and rare variants may colocate in the same disease susceptibility gene, we used next-generation sequencing to sequence these nine published AF susceptibility genes identified by GWAS (a total of 179 exons) in 20 trios, 200 unrelated patients with AF and 200 non-AF controls. RESULTS: We identified a novel mutation in the 5' untranslated region of the PITX2 gene, which localised in the transcriptionally active enhancer region. We also identified one missense exon mutation in KCNN3, two in ZFHX3 and one in SYNE2. None of these mutations were present in other unrelated patients with AF, healthy controls, unaffected parents and are thus novel and de novo (p<10(-4)). Functional study showed that the mutation in the 5' untranslated region of the PITX2 gene significantly downregulated PITX2 expression in atrial myocytes, either in basal condition or during rapid pacing. In silico analysis showed that the missense mutation in ZFHX3 results in damage of the ZFHX3 protein structure. CONCLUSIONS: The genetic architecture of subjects with extreme phenotypes of AF is similar to that of rare or Mendelian diseases, and mutations may be the underlying cause.

Effective and site-specific phosphoramidation reaction for universally labeling nucleic acids.

Here we report efficient and selective postsynthesis labeling strategies, based on an advanced phosphoramidation reaction, for nucleic acids of either synthetic or enzyme-catalyzed origin. The reactions provided phosphorimidazolide intermediates of DNA or RNA which, whether reacted in one pot (one-step) or purified (two-step), were directly or indirectly phosphoramidated with label molecules. The acquired fluorophore-labeled nucleic acids, prepared from the phosphoramidation reactions, demonstrated labeling efficacy by their F/N ratio values (number of fluorophores per molecule of nucleic acid) of 0.02-1.2 which are comparable or better than conventional postsynthesis fluorescent labeling methods for DNA and RNA. Yet, PCR and UV melting studies of the one-step phosphoramidation-prepared FITC-labeled DNA indicated that the reaction might facilitate nonspecific hybridization in nucleic acids. Intrinsic hybridization specificity of nucleic acids was, however, conserved in the two-step phosphoramidation reaction. The reaction of site-specific labeling nucleic acids at the 5'-end was supported by fluorescence quenching and UV melting studies of fluorophore-labeled DNA. The two-step phosphoramidation-based, effective, and site-specific labeling method has the potential to expedite critical research including visualization, quantification, structural determination, localization, and distribution of nucleic acids in vivo and in vitro.

Association of Small-Conductance Calcium-Activated Potassium Channels and Atrial Fibrillation - How Far Have We Gone?

UNLABELLED: Atrial fibrillation (AF) is the most common sustained and most important arrhythmia in clinical practice. The mechanisms underlying AF initiation and maintenance are known to be complex and heterogeneous. The general understanding of the detailed molecular basis of AF is still incomplete. Recently, these is increasing evidence that small conductance calcium-activated potassium (SK) channels are associated with atrial action potential repolarization and the pathogenesis of AF. Although the functional role of SK channels in the genesis of AF is not entirely clear, new insights into the basic pathophysiological mechanism of AF have been provided. Besides, genome-wide association studies also implicate that genes coding for SK channels are related to the risk of developing AF. This article reviews recent work on the association of SK channels and AF, genetic studies of SK channels, and discuss future investigation and developments regarding this field. KEY WORDS: Atrial fibrillation; Genetics; Small conductance calcium-activated potassium channels.

Pattern of Endothelialization in Left Atrial Appendage Occluder by Optic Coherence Tomography: A Pilot Study.

BACKGROUND: Implantation of the left atrial appendage occluder (LAAO) has been proven to prevent stroke effectively in patients with atrial fibrillation who cannot tolerate anticoagulants. Incomplete endothelization of LAAO may cause device-related thrombus, and currently no good image modality exists to clearly see LAAO endothelialization. We aimed to use coronary optic coherence tomography (OCT) to visualize LAAO endothelialization. METHODS AND RESULTS: We enrolled 14 patients (72.8±9.4 years old) undergoing pulmonary vein isolation with a preexisting LAAO implanted more than 1 year ago (5 Watchman and 9 Amulet). After pulmonary vein isolation, we did OCT via steerable sheath and coronary guiding catheter to adjust OCT probe location and injected contrast medium to visualize the LAAO surface. In vitro testing was also performed to see the bare occluder. In vitro OCT showed the surface of the bare device as an interrupted granule pattern, which included the Watchman surface polytetrafluoroethylene membrane string, Amulet disc metal strut, and inner polytetrafluoroethylene membrane string. In the implanted Watchman, OCT showed endothelialization as a smooth surface layer with noninterrupted coarser granules. In the implanted Amulet, OCT showed endothelialization as thin (early) or thick (late) endothelialization layer covering struts with OCT shadows. Among patients with Watchman, 2 showed no, 2 early, and 1 complete endothelialization. Among patients with Amulet, 2 showed no, 3 early, and 4 late endothelialization. CONCLUSIONS: We demonstrated the feasibility of OCT to visualize LAAO endothelization with high resolution. Further studies are needed to determine antithrombotic regimens if incomplete endothelization is detected. A new OCT catheter may be designed specifically for LAAO.

Both HFpEF and HFmrEF should be included in calculating CHA2DS2-VASc score: A Taiwanese longitudinal cohort.

BACKGROUND: Congestive heart failure (CHF) as a risk of stroke in patients with atrial fibrillation (AF) mainly referred to patients with left ventricular systolic dysfunction. Whether this should include patients with preserved ejection fraction is debatable. OBJECTIVE: The study aimed to investigate the variation in stroke risk of AF patients with heart failure with preserved ejection fraction (HFpEF), heart failure with mid-range ejection fraction (HFmrEF), and heart failure with reduced ejection fraction (HFrEF) for enhancing risk assessment and subsequent management strategies. METHODS: In a longitudinal study using the National Taiwan University Hospital integrated Medical Database, 8358 patients with AF were observed for 10 years (mean follow-up, 3.76 years). The study evaluated the risk of ischemic stroke in patients with differing ejection fractions and CHA2DS2-VASc score, further using Cox models adjusted for risk factors of AF-related stroke. RESULTS: Patients with HFpEF and HFmrEF had a higher mean CHA2DS2-VASc score compared with patients with HFrEF (4.30 ± 1.729 vs 4.15 ± 1.736 vs 3.73 ± 1.712; P < .001) and higher risk of stroke during follow-up (hazard ratio [HR], 1.40 [1.161-1.688; P < .001] for HFmrEF; HR, 1.184 [1.075-1.303; P = .001] for HFpEF vs no CHF) after multivariate adjustment). In patients with lower CHA2DS2-VASc score (0-4), presence of any type of CHF increased ischemic stroke risk (HFrEF HR, 1.568 [1.189-2.068; P = .001]; HFmrEF HR, 1.890 [1.372-2.603; P < .001]; HFpEF HR, 1.800 [1.526-2.123; P < .001] vs no CHF). CONCLUSION: After multivariate adjustment, HFpEF and HFmrEF showed a similar risk of stroke in AF patients. Therefore, it is important to extend the criteria for C in the CHA2DS2-VASc score to include patients with HFpEF and HFmrEF. In patients with fewer concomitant stroke risk factors, the presence of any subtype of CHF increases risk for ischemic stroke.

Sodium-Glucose Cotransporter-2 Inhibitor Prevents Stroke in Patients With Diabetes and Atrial Fibrillation.

Background Atrial fibrillation (AF) is associated with increasing risk of thromboembolic or ischemic stroke. The CHA2DS2-VASc score is a well-established predictor of AF stroke. Patients with AF have an increased risk of stroke if they have diabetes. Use of sodium-glucose cotransporter-2 inhibitor (SGLT2i) has been shown to be associated with favorable cardiovascular outcomes in patients with diabetes. It was unknown whether use of SGLT2i decreased stroke risk in patients with AF who have diabetes. Methods and Results A total of 9116 patients with AF and diabetes from the National Taiwan University historical cohort were longitudinally followed up for 5 years (January 2016-December 2020). The risk of stroke related to SGLT2i use was evaluated by Cox model, adjusting CHA2DS2-VASc score in the propensity score-matched population with 474 SGLT2i users and 3235 nonusers. Adverse thromboembolic end points during follow-up were defined as ischemic stroke. The mean age was 73.2±10.5 years, and 61% of patients were men. There were no significant differences of baseline characteristics between users and nonusers of SGLT2i, including CHA2DS2-VASc score in the propensity score-matched population. The stroke rate was 3.4% (95% CI, 2.8-4.2) patient-years in SGLT2i users and 4.3% (95% CI, 4.0-4.6) in nonusers (P=0.021). SGLT2i users had a 20% reduction of stroke (hazard ratio, 0.80 [95% CI, 0.64-0.99]; P=0.043) after adjustment for the CHA2DS2-VASc score. Conclusions Use of SGLT2i was associated with a lower stroke risk in patients with diabetes and AF, and it may be considered to escalate SGLT2i to the first-line treatment in patients with diabetes and AF.

Impact of pre-existing left atrial appendage occluder on catheter ablation of atrial fibrillation.

BACKGROUND: Patients with drug-refractory atrial fibrillation (AF) and pre-existing left atrial appendage occluder (LAAO) device may need pulmonary vein isolation (PVI). In this pioneer study, we investigated the impact of pre-existing LAAO on AF substrates and outcomes of PVI. METHODS: From our AF registry, 65 drug-refractory patients with LAAO (72.1±11.4 years old; CHA2DS2-VASc score 3.7±2.1) were included for PVI. A balanced control group with 124 patients without LAAO receiving PVI (70.9±10.2 years old, CHA2DS2-VASc 3.6±1.9) were included for comparison. RESULTS: We found PVI is feasible in patients with AF with pre-existing LAAO without new peridevice leak. Two patients with LAAO and one without LAAO had stroke during the procedure (2/65 vs 1/124, p=0.272). Complete isolation of left-sided PVs might not be achieved if the device covered the ridge joining the left atrial (LA) appendage to the body of LA. Local electrogram could be detected over LAAO and there was propagation of conduction over the occluder either under sinus rhythm or under atrial arrhythmia. LAAO might modulate LA substrate and induce peridevice fibrosis, peridevice LA flutter and complex fractionate atrial electrogram. The AF recurrent rate at 1 year was similar between the two groups (9.2% vs 8.8%). CONCLUSIONS: This pioneer study first showed impacts of LAAO on LA substrate and PVI procedure.

Bailout left atrial appendage occluder for pulmonary vein isolation and electrical cardioversion in patients with atrial fibrillation and left atrial appendage thrombus: a pilot study.

BACKGROUND: Cardioversion and catheter-based circumferential pulmonary vein isolation (CPVI) are established rhythm control treatment strategies for patients with atrial fibrillation (AF). However, these treatments are contraindicated for AF patients with a left atrial appendage (LAA) thrombus. METHODS: We conducted the first-in-man case series study to evaluate the feasibility and safety of performing cardioversion or CPVI in AF patients with LAA thrombus immediately after implantation of LAA Occluder (LAAO) in a combined procedure. In our multi-center LAAO registry of 310 patients, 27 symptomatic and drug-refractory AF patients underwent a combined procedure of LAAO and CPVI, among whom 10 (mean age 68 ± 16 years, 6 men) having anticoagulant-resistant LAA thrombus received a bailout procedure of LAAO implantation first then CPVI, and the other 17 patients without LAA thrombus received CPVI first then LAAO for comparison. RESULTS: The mean CHA2DS2-VASc score and HAS-BLED score were comparable between these two groups. In patients with LAA thrombus, we put carotid filters and did a no-touch technique, neither advancing the wire and sheath into the LAA nor performing LAA angiography. After LAAO implantation, the connecting cable was still connected to the occluder when cardioversion was performed. During CPVI, the occluder location was registered in the LA geometry by three-dimensional mapping to guide the catheter not to touch the LAAO. The procedure was successful in all the patients without intra-procedural complications. After a mean follow-up of 1.7 ± 0.7 years, there was no device embolization, peri-device leak ≧ 5 mm or stroke event in both groups. The AF recurrence rate was also similar between the two groups (P = 0.697). CONCLUSION: We demonstrated that cardioversion or CPVI is doable in symptomatic AF patients with LAA thrombus if LAA was occluded ahead as a bailout procedure.

Urine output as one of the most important features in differentiating in-hospital death among patients receiving extracorporeal membrane oxygenation: a random forest approach.

BACKGROUND: It is common to support cardiovascular function in critically ill patients with extracorporeal membrane oxygenation (ECMO). The purpose of this study was to identify patients receiving ECMO with a considerable risk of dying in hospital using machine learning algorithms. METHODS: A total of 1342 adult patients on ECMO support were randomly assigned to the training and test groups. The discriminatory power (DP) for predicting in-hospital mortality was tested using both random forest (RF) and logistic regression (LR) algorithms. RESULTS: Urine output on the first day of ECMO implantation was found to be one of the most predictive features that were related to in-hospital death in both RF and LR models. For those with oliguria, the hazard ratio for 1 year mortality was 1.445 (p < 0.001, 95% CI 1.265-1.650). CONCLUSIONS: Oliguria within the first 24 h was deemed especially significant in differentiating in-hospital death and 1 year mortality.

Significant association of rs13376333 in KCNN3 on chromosome 1q21 with atrial fibrillation in a Taiwanese population.

BACKGROUND: A recent study in individuals of European ancestry demonstrated a significant association of the single nucleotide polymorphism (SNP) rs13376333 in potassium intermediate/small conductance calcium-activated channel, subfamily N, member 3 (KCNN3) on chromosome 1q21 with lone atrial fibrillation (AF), indicating a common genetic basis for AF. The aim of the present study was to investigate whether this association between SNP rs13376333 and AF also exists in Taiwanese subjects. METHODS AND RESULTS: The SNP rs13376333 was compared in 214 lone AF patients (58.3±11.4 years) vs. 214 controls (57.7±13.2 years), and in 322 structural AF patients (69.6±13.7 years) vs. 322 controls (68.4±14.2 years) in a Taiwanese population, in a case-control design. The associations between SNP rs13376333 in KCNN3 and structural or lone AF were significant. In the lone AF group, the frequency of the minor allele of SNP rs13376333 was 8.6% compared with 3.0% in the controls (P<0.001; odds ratio [OR], 3.02; 95% confidence interval [CI]: 1.54-6.29). The frequency of the minor allele of SNP rs13376333 was 6.5% in structural AF patients compared with 3.1% in controls (P=0.004; OR, 2.18; 95%CI: 1.23-3.96). CONCLUSIONS: There are significant associations between SNP rs13376333 and the risk of developing both lone and structural AF in the Taiwanese population. The minor allele frequency of SNP rs13376333 was much lower in the Taiwanese population compared to that in the Caucasian population.