The Report of Community-Based and Government-Endorsed Screening Program of Atrial Fibrillation in Taiwan.

BACKGROUND: Although international guidelines recommended opportunistic screening for atrial fibrillation (AF), the community-based AF screening program incorporated into the government-endorsed health care system is rarely reported in Asian countries. OBJECTIVES: We aimed to test the feasibility of adding AF screening into the preexistent adult health check program and report the AF detection rate and percentages of OAC prescriptions before and after AF screening with the involvement of public health care systems. METHODS: We performed this program in three counties (Chiayi county, Keelung City, and Yilan county) in Taiwan which have their own official preexistent adult health check programs conducted by public health bureaus for years. However, electrocardiography (ECG) was not included in these programs before. We cooperated with the public health bureaus of the three counties and performed single-lead 30-second ECG recording for every participant. RESULTS: From January to December 2020, AF screening was performed in 199 sessions with 23,572 participants. AF was detected in 278 subjects with a detection rate of 1.19% (age ≥65 years: 2.39%; ≥75 years: 3.73%). The mean CHA2DS2-VASc score of these 278 subjects was 2.36, with 91% of them had a score ≥1 (males) or ≥2 (females). The number needed to screen was 42 and 27 for subjects aged ≥65 and ≥75 years, respectively. The prescription rate of OACs significantly increased from 11.4 to 60.6% in Chiayi county and from 15.8 to 50.0% in Keelung City after screening (both p-values <0.001). CONCLUSION: This community-based and government-endorsed AF screening project in Taiwan demonstrated that incorporation of AF screening into the preexistent adult health check programs through co-operations with the government was feasible. Actions to detect AF, good education, and well-organized transferring plan after AF being detected with the involvement of public health care systems could result in a substantial increase in the prescription rate of OACs.

Altered subgroups of regulatory T cells in patients with primary Sjögren's syndrome.

Primary Sjögren syndrome (pSS) is a systemic autoimmune inflammatory disease. Up to now, the role of regulatory T cells (Tregs) and their subgroups in pSS is still in controversial. In this study we tried to elucidate the roles of Tregs and its subgroups in pSS. Total 43 pSS patients and 23 health persons as control were enrolled in this study. We grouped the pSS patients according to the anti-SSa/SSb and the EULAR Sjögren's syndrome disease activity index (ESSDAI). Among the 43 pSS patients, 14 patients were followed after treatment. The percentage of rTregs (resting Treg cells) among Tregs was increased in the pSS group, and decreased after treatment. In the high disease activity subpopulation (ESSDAI ≥ 5), the percentage of rTregs among Tregs decreased after treatment. On the contrary, the percentage of aTregs (activated Treg cells) increased after treatment. It was in an inverse correlation between the percentage of aTreg and rTreg in pSS patients. The Tregs are co-cultured with responder T cells. Tregs from pSS patients showed poorer proliferation inhibitory function. Our results show that the percentages of Tregs and their subgroups altered in pSS patients. The percentage of aTreg and the percentage of rTreg have an inverse correlation in pSS patients. Compared to the control group, the percentage of rTregs among Tregs was increased in the pSS patients and decreased after the treatment. Our study also showed that The Tregs from pSS patients may have poorer inhibitory functions.

The Role of Cardiac Fibrosis in Diabetic Cardiomyopathy: From Pathophysiology to Clinical Diagnostic Tools.

Diabetes mellitus (DM) is a chronic metabolic disorder characterized by hyperglycemia due to inadequate insulin secretion, resistance, or both. The cardiovascular complications of DM are the leading cause of morbidity and mortality in diabetic patients. There are three major types of pathophysiologic cardiac remodeling including coronary artery atherosclerosis, cardiac autonomic neuropathy, and DM cardiomyopathy in patients with DM. DM cardiomyopathy is a distinct cardiomyopathy characterized by myocardial dysfunction in the absence of coronary artery disease, hypertension, and valvular heart disease. Cardiac fibrosis, defined as the excessive deposition of extracellular matrix (ECM) proteins, is a hallmark of DM cardiomyopathy. The pathophysiology of cardiac fibrosis in DM cardiomyopathy is complex and involves multiple cellular and molecular mechanisms. Cardiac fibrosis contributes to the development of heart failure with preserved ejection fraction (HFpEF), which increases mortality and the incidence of hospitalizations. As medical technology advances, the severity of cardiac fibrosis in DM cardiomyopathy can be evaluated by non-invasive imaging modalities such as echocardiography, heart computed tomography (CT), cardiac magnetic resonance imaging (MRI), and nuclear imaging. In this review article, we will discuss the pathophysiology of cardiac fibrosis in DM cardiomyopathy, non-invasive imaging modalities to evaluate the severity of cardiac fibrosis, and therapeutic strategies for DM cardiomyopathy.

Effect of the Ligation and Reperfusion Timeframe on Maximal Ischemia-Reperfusion Injury in Diverse Rat Models.

Background: Little is known about the effect that different time sequences for coronary ligation and reperfusion have on ischemic-reperfusion (IR) injury. Objective: To investigate the relationship between the extent of IR injury and the timeframe for coronary ligation/reperfusion in three animal models. Methods: Three rat models were used: normal Sprague-Dawley rats, diabetes mellitus (DM) rats, and fat rats. The rats in each model were divided into four groups based on the coronary ligation period (L): 30, 60, 120, and 180 min, and then divided into seven sub-groups based on the reperfusion period (R): 0, 30, 60, 120, 180, 270, and 360 min. R0 was the IR injury baseline for each sub-group. The hearts were harvested and stained with Evans blue and 2,3,5-triphenyl tetrazolium chloride dye to distinguish the different myocardial injury areas: area at risk (AAR) and myocardial necrosis. The difference between each subgroup and baseline (R0) for the necrotic area/AAR was calculated. Results: In the normal rats, the highest IR injury differences compared with the baseline group occurred at L120, with a reperfusion time of > 180 min. The highest IR injury difference compared to the baseline group occurred at L30, with a reperfusion time of > 180 min in the DM rats and at L60R270, L120R180 in the fat rats. Conclusions: IR injury, as induced by different coronary ligation and reperfusion time intervals, had diverse expression profiles in the different animal models. Optimal animal models with optimal coronary ligation/reperfusion protocols to achieve maximal IR injury will affect the results and interpretation of future studies.

Estimation of Left Ventricular Ejection Fraction Using Cardiovascular Hemodynamic Parameters and Pulse Morphological Characteristics with Machine Learning Algorithms.

It is estimated that 360,000 patients have suffered from heart failure (HF) in Taiwan, mostly those over the age of 65 years, who need long-term medication and daily healthcare to reduce the risk of mortality. The left ventricular ejection fraction (LVEF) is an important index to diagnose the HF. The goal of this study is to estimate the LVEF using the cardiovascular hemodynamic parameters, morphological characteristics of pulse, and bodily information with two machine learning algorithms. Twenty patients with HF who have been treated for at least six to nine months participated in this study. The self-constructing neural fuzzy inference network (SoNFIN) and XGBoost regression models were used to estimate their LVEF. A total of 193 training samples and 118 test samples were obtained. The recursive feature elimination algorithm is used to choose the optimal parameter set. The results show that the estimating root-mean-square errors (ERMS) of SoNFIN and XGBoost are 6.9 ± 2.3% and 6.4 ± 2.4%, by comparing with echocardiography as the ground truth, respectively. The benefit of this study is that the LVEF could be measured by the non-medical image method conveniently. Thus, the proposed method may arrive at an application level for clinical practice in the future.

Sarcomeres Morphology and Z-Line Arrangement Disarray Induced by Ventricular Premature Contractions through the Rac2/Cofilin Pathway.

The most common ventricular premature contractions (VPCs) originate from the right ventricular outflow tract (RVOT), but the molecular mechanisms of altered cytoskeletons of VPC-induced cardiomyopathy remain unexplored. We created a RVOT bigeminy VPC pig model (n = 6 in each group). Echocardiography was performed. The histopathological alternations in the LV myocardium were analyzed, and next generation sequencing (NGS) and functional enrichment analyses were employed to identify the differentially expressed genes (DEGs) responsible for the histopathological alternations. Finally, a cell silencing model was used to confirm the key regulatory gene and pathway. VPC pigs had increased LV diameters in the 6-month follow-up period. A histological study showed more actin cytoskeleton disorganization and actin accumulation over intercalated disc, Z-line arrangement disarray, increased ß-catenin expression, and cardiomyocyte enlargement in the LV myocardium of the VPC pigs compared to the control pigs. The NGS study showed actin cytoskeleton signaling, RhoGDI signaling, and signaling by Rho Family GTPases and ILK Signaling presented z-scores with same activation states. The expressions of Rac family small GTPase 2 (Rac2), the p-cofilin/cofilin ratio, and the F-actin/G-actin ratio were downregulated in the VPC group compared to the control group. Moreover, the intensity and number of actin filaments per cardiomyocyte were significantly decreased by Rac2 siRNA in the cell silencing model. Therefore, the Rac2/cofilin pathway was found to play a crucial role in the sarcomere morphology and Z-line arrangement disarray induced by RVOT bigeminy VPCs.

Neuropsychiatric and cognitive symptoms in people with hypertension: An examination with the NINDS-CSN consensus protocol.

Hypertension has been associated with risk of cognitive impairments. The American Heart Association recommended the use of the harmonized neuropsychological protocol suggested by the National Institute of Neurologic Disorders and Stroke and the Canadian Stroke Network (NINDS-CSN) for studying related cognitive impairments. Initially designed for vascular cognitive impairment, empirical data of results from NINDS-CSN protocol has not been well-established in hypertension. The present study recruited 58 adults diagnosed with hypertension and 44 normotensive controls. Tests from the NINDS-CSN protocol were given in three lengths, including neuropsychological tests and neuropsychiatric inventories. The results showed higher proportions of hypertensive adults with impairments on tests of memory and executive functions and that they performed worse as a group on several tests from the 30-minute protocol, but not on the other additional tests in the full-length version, nor on cognitive screening test in the 5-minute protocol such as the Mini-Mental State Examination or the Montreal Cognitive Assessment. There was no significant group difference on neuropsychiatric symptoms. These findings suggested that the 30-minute version of the NINDS-CSN protocol with the two supplemental tests was able to reveal selective cognitive deficits in hypertensive adults and provide a practical solution for related studies, balancing between the requirement of sensitivity, domain variety, and brevity.

Is it possible to expect left ventricular ejection fraction improvement in patients with known advanced heart diseases in the case of right atrial flutter treated by ablation?

BACKGROUND: Atrial flutter (AFL)-related tachycardia-induced cardiomyopathy (TICM) is a treatable cause of heart failure (HF). This study aims to explore the effect of AFL ablation on left ventricular (LV) function in right AFL patients with or without advanced heart diseases. METHODS: Between January 2013 and December 2019, 149 patients underwent ablation for persistent AFL. Among them, 60 patients with persistent right atrial (RA) flutter had symptomatic HF and elevated natriuretic peptide levels. Group 1 consisted of 35 patients without advanced heart diseases, and group 2 consisted of 25 patients with prior history of ischemic cardiomyopathy (ICM), dilated cardiomyopathy (DCM) or surgery for valvular heart disease (VHD). Follow-up echocardiography was performed 6 months later. Improvement of LV performance was defined as LV ejection fraction (EF) increase ≥50% of baseline EF without clinical HF symptoms or LVEF recovery to ≥60%. RESULTS: Group 2 had larger LV end-diastolic volume (LVEDV) and LV end-systolic volume than group 1. At follow-up, group 2 had larger LV end-systolic volume than group 1. Group 1 had more increase in LVEF than group 2 (21.7 ± 15.2% vs 4.1 ± 13.2%; P < .001). A receiver operating characteristic curve was constructed to determine the discrimination threshold of baseline LVEDV (137 mL) in the overall study group for improvement of LV performance after ablation (P = .005). CONCLUSIONS: Successful ablation for right AFL could achieve more reversal of LV dysfunction in patients without advanced heart diseases. Pre-ablation LVEDV ≥ 137 mL was associated with no improvement of LV performance after ablation.

Progressive tricuspid regurgitation and elevated pressure gradient after transvenous permanent pacemaker implantation.

BACKGROUND: The association of postimplant tricuspid regurgitation (TR) and heart failure (HF) hospitalization in patients without HF and preexisting abnormal TR and TR pressure gradient (PG) remain unclear. HYPOTHESIS: This study aimed to explore the clinical outcomes of progressive postimplant TR after permanent pacemaker (PPM) implantation. METHODS: A total of 1670 patients who underwent a single ventricular or dual-chamber transvenous PPM implantation at our hospital between January 2003 and December 2017 were included in the study. Patients with prior valvular surgery, history of HF, and baseline abnormal TR and TRPG were excluded. Finally, a total of 1075 patients were enrolled in this study. Progressive TR was defined as increased TR grade of ≥2 degrees and TRPG of >30 mmHg after implant. RESULTS: In 198 (18.4%) patients (group 1) experienced progressive postimplant TR and elevated TRPG, whereas 877 patients (group 2) did not have progressive postimplant TR. Group 1 had larger change in postimplant TRPG (group 1 vs. group 2; 12.8 ± 9.6 mmHg vs. 1.1 ± 7.6 mmHg; p < .001) than group 2. Group 1 had a higher incidence of HF hospitalization compared to group 2 (13.6% vs. 4.7%; p < .001). Preimplant TRPG (HR: 1.075; 95% confidence interval [CI]: 1.032-1.121; p = .001) was an independent predictor of progressive postimplant TR. CONCLUSIONS: After a transvenous ventricular-based PPM implantation, 18.4% of patients experienced progressive postimplant TR and elevated TRPG. Higher preimplant TRPG was an independent predictor of progressive postimplant TR.

An Examination System to Detect Deep Vein Thrombosis of a Lower Limb Using Light Reflection Rheography.

Deep vein thrombosis (DVT) of lower limbs can easily arise from prolonged sitting or standing. Elders and pregnant women are most likely to have this disease. When the embolus of DVT comes to pass the lung, it will become a life-threatening disease. Thus, for DVT disease, early detection and the early treatment are needed. The goal of this study was to develop an examination system to be used at non-medical places to detect the DVT of lower limbs with light reflection rheography (LRR). Consisting of a wearable device and a mobile application (APP), the system is operated in a wireless manner to control the actions of sensors and display and store the LRR signals on the APP. Then, the recorded LRR signals are processed to find the parameters of DVT examination. Twenty subjects were recruited to perform experiments. The veins of lower limbs were occluded by pressuring the cuff up to 100 mmHg and 150 mmHg to simulate the slight and serious DVT scenarios, respectively. Six characteristic parameters were defined to classify whether there was positive or negative DVT using the receiver operating characteristic curves, including the slopes of emptying and refilling curves in the LRR signal, and the changes of venous pump volume. Under the slight DVT scenario (0 mmHg vs. 100 mmHg), the first three parameters, m10, m40, and m50, had accuracies of 72%, 69%, and 69%, respectively. Under the serious DVT scenario (0 mmHg vs. 150 mmHg), m10, m40, and m50 achieved accuracies of 73%, 76%, and 73%, respectively. The experimental results show that this proposed examination system may be practical as an auxiliary tool to screen DVT in homecare settings.

Catheter Ablation Compared with Medical Therapy for Atrial Fibrillation with Heart Failure: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

Background: The optimal strategy for patients with coexisting atrial fibrillation (AF) and heart failure (HF) was not settled. Our purpose was to conduct a systematic review and meta-analysis of randomized controlled trials to evaluate the effect of catheter ablation compared with medical therapy for AF on mortality, HF hospitalization, left ventricular (LV) function, and quality of life among patients with HF and AF. Materials and Methods: We searched Pubmed (1966 to September 20, 2019), EMBASE (1966 to September 20, 2019), the Cochrane Central Register of Controlled Trials (CENTRAL), and ClinicalTrials.gov for randomized controlled trials with a comparison of catheter ablation for AF with medical therapy among patients with coexisting AF and HF. Risk ratio (RR) or mean difference (MD) with 95% confidence interval (CI) was used as a measure of the effect of catheter ablation versus medical therapy on endpoints. Our final analysis included 6 randomized control trials with 775 patients. Results: Pooled results from the random-effects model showed that compared with medical therapy for AF, catheter ablation was associated with reduced all-cause mortality (RR 0.52, 95%Cl, 0.35 to 0.76) and HF hospitalization (RR 0.56, 95%Cl, 0.44 to 0.71), as well as increased LV ejection fraction (LVEF), distance walked in six minutes, and improvements in quality of life. Conclusions: This updated meta-analysis showed that compared to medical therapy, catheter ablation for AF was associated with significant benefits in several key clinical and biomarker endpoints, including reductions in all-cause mortality and HF hospitalization.

Left Ventricular Electromechanical Remodeling Detected by Acoustic Cardiography in Paroxysmal Atrial Fibrillation.

This study aimed to investigate the electromechanical function detected by acoustic cardiography before and after radiofrequency ablation therapy (RFA) in paroxysmal AF (PAF) patients with preserved left ventricular ejection fraction (LVEF). Seventy-five symptomatic PAF patients and 69 patients without arrhythmia were enrolled. Thirty-seven PAF patients received RFA therapy. Acoustic cardiographic exam was performed to check S3 and S4 heart sound, electromechanical activation time (EMAT), LV systolic time percentage (LVST), and systolic dysfunction index (SDI) in all participants. Furthermore, 37 PAF patients also received follow-up acoustic cardiography postRFA. PAF had impaired electromechanical systolic function compared with health participants (%EMAT 14.69 ± 3.62 vs. 10.84 ± 2.62; %LVST 40.83 ± 5.14 vs. 36.70 ± 3.87; SDI 4.75 ± 1.61 vs. 3.26 ± 0.96 all p < 0.001). RFA can improve electromechanical systolic function. Improvement below 13.1% could predict the recurrent AF postcatheter ablation. Higher degree of improved electromechanical systolic function postRFA contribute to lower recurrence of AF. Graphical Abstract Receiver operating characteristic (ROC) curve analysis for % change of systolic dysfunction index (SDI) postRFA in the detection of recurrent AF.

Usefulness of serial post-systolic shortening by speckle tracking echocardiography to predict major adverse cardiovascular events and segmental function improvement after acute myocardial infarction.

PURPOSE: The aim is to determine whether serial post-systolic shortening (PSS) using speckle tracking echocardiography (STE) could predict major adverse cardiovascular events (MACE), especially symptom-driven infarct-related artery (IRA) revascularization and improvement in segmental function in post-myocardial infarction patients. METHODS/RESULTS: Ninety-four patients (average age 61.1 ± 12.5 y, 84 [84.9%] male) with new-onset acute myocardial infarction were enrolled. Serial echocardiography was performed during the initial presentation, and at 3, 6 and 12 months after admission. PSS, strain and systolic strain rate were calculated using STE. Improvement in segmental function was defined as a decrease of ≧1 grade in wall motion score. During the follow-up (29.4 ± 12.7months), 22 patients (23.4%) had MACE and 17 patients had symptom-driven IRA revascularization. In multivariate model, PSS at 3 months was independently predictive for symptom-driven IRA revascularization (Hazard ratio (HR) = 0.5, 95% CI = 0.26-0.97) and for MACE (HR = 0.4, 95% CI = 0.24-0.67) (p < 0.05). Segmental function improvements were found in 255 segments (66.1%) and ROC curve analyses showed that AUC (95% CI) of the initial PSS was 0.7(0.65-0.77) (cut-off values = -1.08, sensitivity = 58%, specificity = 73% specificity). CONCLUSIONS: Post-systolic shortening at 3 months is an independent predictor for symptom-driven IRA revascularization and MACE. Regional wall motion recovery also could be predicted by initial PSS. Serial assessment of two-dimensional STE should be investigated in post-myocardial infarction patients in the future.

Inhibition of Notch Signaling Alleviated Diabetic Macrovasculopathy in an In Vitro Model.

BACKGROUND: Interactions between endothelial cells and vascular smooth muscle cells (VSMCs) through the Notch signal pathway causing diabetic microvasculopathy have been reported. OBJECTIVES: The purpose of this study was to investigate whether the effect of high glucose on VSMCs through the Notch-2 signaling pathway could induce extracellular matrix (ECM) accumulation, VSMC proliferation and migration and thus directly mediate diabetic macrovasculopathy. METHODS: Rat smooth muscle cells (SV40LT-SMC Clone HEP-SA cells) were cultured in different concentrations of D-glucose to evaluate the impact of high glucose on ECM accumulation including fibronectin and collagen I measured by Western blot analysis, and on VSMC proliferation and migration evaluated by MTT assay and wound healing assay. The expression of Notch-2 intra-cellular domain (Notch-2 ICD) protein was also checked in high glucose-stressed VSMCs. N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester (DAPT), an inhibitor of γ-secretase, was used to modulate the Notch-2 signaling pathway. RESULTS: High glucose (D-glucose 25 mM) induced fibronectin and collagen I expressions in VSMCs, promoted VSMC proliferation/migration, and enhanced the expression of Notch-2 ICD. DAPT inhibited Notch-2 signal to abolish the expressions of fibronectin and collagen I in VSMCs, and also prevented the proliferation/migration of VSMCs under high glucose (D-glucose 25 mM) stress. CONCLUSIONS: Our study suggests that high glucose can enhance the Notch-2 signaling pathway thereby directly mediating diabetic macrovasculopathy. Blocking the Notch-2 signaling pathway decreased fibronectin and collagen I expressions secreted by VSMCs, and reduced the proliferation and migration of VSMCs under high glucose stress. Inhibition of Notch-2 signaling represents a promising target for treating diabetic macrovasculopathy.

Additional cavotricuspid isthmus block ablation may not improve the outcome of atrial fibrillation ablation.

AIMS: Pulmonary vein isolation (PVI) is an effective procedure for atrial fibrillation (AF). The role of additional cavotricuspid isthmus (CTI) block ablation remains controversial in AF patients without atrial flutter (AFL). Therefore, this study aimed to explore the clinical outcome of additional CTI block ablation in patients without AFL. METHODS: Between January 2013 and December 2017, a total of 139 patients who did not have documented AFL and who underwent catheter ablation for AF were recruited. Fifty-seven patients were classified in additional CTI block ablation group and 82 patients were classified in without CTI group. The incidence of early-onset and late-onset atrial arrhythmia recurrence was compared between the two groups. RESULTS: The additional CTI group had a higher prevalence of persistent or long-standing AF and larger left atrial volume. The additional CTI group had a higher incidence of late-onset atrial arrhythmia recurrence (38.6% vs 12.2%; P < .001). When compared to without CTI group, additional CTI therapy did not have a better outcome in terms of freedom of atrial arrhythmia in subgroup analysis. The incidence of early-onset and late-onset atrial arrhythmia recurrence did not differ between additional CTI group and without CTI group in paroxysmal AF patients and nonparoxysmal AF patients after propensity scoring matching. CONCLUSION: CTI block ablation in addition to PVI for AF patients without a history of AFL or inducible AFL during ablation may not improve the clinical outcome of AF ablation in the patients with larger LA volume, nonparoxysmal AF, or post-PVI inducible AF.

Late fractionated potentials in catheter ablation for right ventricular outflow tract ventricular arrhythmias.

BACKGROUND: Endocardial late fractionated potentials during sinus rhythm mapping may reflect abnormal "subendocardial" substrates associated with right ventricular outflow tract (RVOT) ventricular arrhythmias (VAs). The aim of this study was to explore the clinical outcomes of catheter ablation guided by these late fractionated potentials for RVOT VAs in patients without structural heart disease. METHODS: From January 2016 to March 2018, 28 patients underwent catheter ablation for RVOT premature ventricular contractions (PVCs) or ventricular tachycardia (VT), guided by the EnSite NavX or Velocity V5.0 three-dimensional mapping system (Abbott, St. Paul, MN, USA). Among them, 10 patients (35.7%) were found to have endocardial late fractionated potentials during sinus rhythm mapping (Group 1). Group 2 was composed of 18 patients in whom no endocardial late fractionated potentials were seen. The burden of VAs, acute procedural success, and 3-month clinical outcomes were analyzed. RESULTS: The average duration of late fractionated potentials after the end of QRS during sinus rhythm mapping in group 1 was 45.00 ± 17.15 ms. Baseline demographics and morphology and burden of PVCs were similarly distributed between both groups. Group 1 had higher acute procedural success compared to group 2 (100% vs 66.7%; P = .039). Moreover, at 3-month follow-up, group 1 had lower total PVCs (49 (1-5986) versus 4316 (1-23231); P = .048), PVC burden (0% (0-5.9) vs 4.3% (0-18.9); P = .055), and higher clinical success (100% vs 55.6%; P = .025) compared to group 2. CONCLUSION: The identification and elimination of endocardial late fractionated potentials during sinus rhythm mapping could improve the acute success and short-term outcomes of ablation for RVOT VAs.

Post-pacemaker implant QRS duration and heart failure admission in patients with sick sinus syndrome and complete atrioventricular block.

AIMS: High demand right ventricular pacing may elicit left ventricular systolic dysfunction known as pacing-induced cardiomyopathy, increasing the risks of heart failure (HF) hospitalization. Percentage of demand ventricular pacing is different between patients with sick sinus syndrome (SSS) and those with complete atrioventricular block (CAVB). This study aims to compare the incidence of HF admission and pacing-induced cardiomyopathy between patients with SSS and CAVB. METHODS AND RESULTS: A total of 824 patients who received single ventricular or dual-chamber pacemaker implantation at our hospital between January 2003 and December 2012 were recruited for the study. Patients with HF, those without complete cardiac echocardiography, and those with significant coronary artery disease were excluded. Finally, 315 patients with SSS and 289 patients with CAVB were enrolled in this study. The CAVB group had a higher pacing percentage (39.37 ± 9.17% vs. 83.82 ± 33.06%; P < 0.001), longer pacing QRS duration (142.56 ± 33.02 ms vs. 156.63 ± 25.18 ms; P < 0.001), and higher prevalence of follow-up left ventricular ejection fraction ≤40% (1.3% vs. 4.2%; P = 0.040). However, the incidence of HF admission was similar between the two groups (log-rank P = 0.647). Age [hazard ratio (HR), 95% confidence interval (CI): 1.121, 1.054-1.193], diabetes mellitus (HR, 95% CI: 2.667, 1.159-6.136), pacing QRS duration ≥163 ms (HR, 95% CI: 3.506, 1.491-8.247), and left atrial size (HR, 95% CI: 1.070, 1.012-1.131) were independent predictors of HF admission. The Kaplan-Meier curve showed a significant difference in HF admission over a 3.5 year follow-up period (3.5 years: P value = 0.004; 5 years: P value = 0.002) between patients with pacing QRS duration ≥163 and <163 ms. CONCLUSIONS: There was no difference in HF admission between patients with SSS and CAVB, although the CAVB group had a higher pacing percentage. Post-pacemaker implant pacing QRS duration ≥163 ms was the most important predictor of HF admission.

Common pulmonary vein on the recurrence of atrial tachyarrhythmia after pulmonary vein isolation.

AIMS: Catheter ablation has become an effective treatment modality for atrial fibrillation (AF). However, the relationship between common pulmonary vein (PV) and recurrent atrial tachyarrhythmia (ATA) after PV isolation (PVI) remains controversial. This study aimed to explore the function of common PV on the risk of recurrent ATA after PVI. METHODS: We identified a total of 191 patients who received radiofrequency catheter ablation for paroxysmal AF at our hospital between July 2010 and December 2017 for retrospective chart review. We collected the following data for analysis: results of preprocedural computed tomography, including the anatomy of PV and left atrial (LA) volume; the incidence of early- and late-onset recurrence of ATA. We compared these characteristics between the two groups defined by the presence or absence of the late-onset recurrence of ATA. RESULTS: Compared to the no ATA recurrence group, the ATA recurrence group had larger LA size, larger LA end-diastolic and systolic volumes, larger maximal diameter of PV, higher prevalence of common PV, and higher incidence of early-onset recurrence of ATA. In multivariate logistic regression analyses, presence of common PV and early-onset recurrence were independently associated with late-onset recurrence of ATA. Compared to patients without common PV, patients with common PV had larger diameter of PV and higher incidence of late-onset recurrent ATA. CONCLUSION: In patients with paroxysmal AF, early-onset recurrence of ATA and the presence of common PV were independently associated with late-onset recurrent ATA after radiofrequency catheter ablation.

Shorter Leukocyte Telomere Length Is Associated With Atrial Remodeling and Predicts Recurrence in Younger Patients With Paroxysmal Atrial Fibrillation After Radiofrequency Ablation.

BACKGROUND: Telomere length is a biologic aging marker. This study investigated leukocyte telomere length (LTL) as a new biomarker to predict recurrence after paroxysmal atrial fibrillation (PAF) ablation.Methods and Results:A total of 131 participants (26 healthy individuals and 105 symptomatic PAF patients) were enrolled. PAF patients (54.1±10.8 years) who received catheter ablation therapy were divided into 2 groups: recurrent AF (n=25) and no recurrent AF after catheter ablation (n=80). Peripheral blood mononuclear cells were collected from all subjects to measure LTL. Under 50 years old, LTL in healthy individuals (n=17) was longer than in PAF patients (n=31; 7.34±0.58 kbp vs. 6.44±0.91 kbp, P=0.01). In PAF patients, LTL was positively correlated with left atrial bipolar voltage (R=0.497, P<0.001), and negatively correlated with biatrial scar area (R=-0.570, P<0.001) and left atrial diameter (R=-0.214, P=0.028). LTL was shorter in the patients with recurrent AF than in those without recurrent AF after catheter ablation (5.68±0.82 kbp vs. 6.66±0.71 kbp; P<0.001). On receiver operating characteristic curve analysis, LTL cut-off <6.14 kbp had a specificity of 0.68 and sensitivity of 0.79 to predict recurrent AF after catheter ablation. CONCLUSIONS: Young PAF patients (≤50 years) had shorter LTL. Shorter LTL was associated with a degenerative atrial substrate and recurrence after catheter ablation in younger PAF patients.

Liver X Receptor/Retinoid X Receptor Pathway Plays a Regulatory Role in Pacing-Induced Cardiomyopathy.

Background The molecular mechanisms through which high-demand pacing induce myocardial dysfunction remain unclear. Methods and Results We created atrioventricular block in pigs using dependent right ventricular septal pacing for 6 months. Echocardiography was performed to evaluate dyssynchrony between pacing (n=6) and sham control (n=6) groups. Microarray and enrichment analyses were used to identify differentially expressed genes ( DEG s) in the left ventricular ( LV ) myocardium between pacing and sham control groups. Histopathological and protein changes were also analyzed and an A cell pacing model was also performed. Pacing significantly increased mechanical dyssynchrony. Enrichment analysis using Ingenuity Pathway Analysis and the activation z-score analysis method demonstrated that there were 5 DEG s ( ABCA 1, APOD , CLU , LY 96, and SERPINF 1) in the LV septum (z-score=-0.447) and 5 DEG s ( APOD , CLU , LY 96, MSR 1, and SERPINF 1) in the LV free wall (z-score=-1.000) inhibited the liver X receptor/retinoid X receptor ( LXR / RXR ) pathway, and 4 DEG s ( ACTA 2, MYL 1, PPP 2R3A, and SNAI 2) activated the integrin-linked kinase ( ILK ) pathway in the LV septum (z-score=1.000). The pacing group had a larger cell size, higher degree of myolysis and fibrosis, and increased expression of intracellular lipid, inflammatory cytokines, and apoptotic markers than the sham control group. The causal relationships between pacing and DEG s related to LXR / RXR and ILK pathways, apoptosis, fibrosis, and lipid expression after pacing were confirmed in the cell pacing model. Luciferase reporter assay in the cell pacing model also supported inhibition of the LXR pathway by pacing. Conclusions Right ventricular septal-dependent pacing was associated with persistent LV dyssynchrony-induced cardiomyopathy through inhibition of the LXR / RXR pathway.