Atrial Flutter Research Articles

The impact of right atrial volume on ablation outcomes in patients with pulmonary hypertension and atrial flutter

BackgroundCatheter ablation has evolved as a safe treatment for atrial flutter (AFL) in patients with pulmonary hypertension (PH), and the recurrence of AFL may accelerate clinical decompensation. The aim of this study was to determine the recurrence rate and risk factors for recurrent AFL in PH patients after ablation.MethodsAll PH patients who underwent AFL ablation at Fuwai Hospital between May 2015 and December 2020 were followed up. The recurrence rate and risk factors for recurrence were analyzed.ResultsA total of 68 PH patients (mean age 44.0 ± 13.0 years, 36.8% male) were enrolled. The majority patients diagnosed PH had congenital heart disease-associated PH (63.2%), and 30.9% had idiopathic pulmonary arterial hypertension. At baseline, most patients (80.9%) had only cavotricuspid isthmus (CTI)-related AFL; the occurrence of non-CTI-related AFL among patients was 8.8%, and 10.3% of the patients had both types of AFL. During a median follow-up of 17.5 months, 22 patients developed at least one recurrent AFL episode (AFL-free survival: 76.5% at 1 year). The immediate success of ablation (HR 0.061, 95% CI 0.009 to 0.438; P = 0.005) and the right atrial volume index (RAVi, per 10 ml/m2; HR 1.064, 95% CI 1.011 to 1.120; P = 0.018) were associated with long-term ablation outcomes in PH patients. With 166.64 ml/m2 as a cutoff value, AFL-free survival was significantly greater in patients whose RAVi was < 166.64 ml/m2 (log-rank P = 0.024).ConclusionThe immediate success of ablation and the RAVi are associated with recurrent AFL. Patients with a RAVi ≥ 166.64 ml/m2 are likely experience recurrence.

Caught in the Act: A Detailed Analysis of Cardiac Event Monitoring in a Cohort of Pediatric and ACHD Patients.

Event monitors are being increasingly used in pediatric and adult congenital heart disease (ACHD) patients for arrhythmia evaluation. Data on their diagnostic yield are limited. To evaluate the diagnostic yield of event monitors, patient characteristics associated with critical events, and clinical response to events. We retrospectively assessed event monitors prescribed to patients at our institution's Heart Center from 2017 to 2020. Thirty-day event monitor tracings were reviewed by an electrophysiologist (EP) to identify critical events defined as supraventricular tachycardia (SVT, re-entrant, atrial tachycardia, atrial flutter, and atrial fibrillation), ventricular tachycardia (VT), atrioventricular block, and pauses greater than 3 s. Patient characteristics and treatment data were collected. Characteristics associated with events were assessed using multivariable logistic regression. Trends in monitor prescription over time, diagnostic yield, and clinical response to events were analyzed. 204/2330 (8.8%) event monitors had EP-confirmed critical events. Critical events included SVT (51.5%), VT (38.5%), atrioventricular block (4%), and pauses (6%). 129/198 (65%) patients with critical events underwent treatment. Event monitoring usage increased by 52% between 2017 and 2020 (p<0.0001). Complex CHD (OR 2.1, 95% CI 1.3-3.4, p=0.004), cardiomyopathy (OR 2.9, 95% CI 1.5-4.8, p<0.001), and EP-ordered monitors (OR 1.6, 95% CI 1.2-2.1, p=0.001) were more highly associated with critical events. Event monitor use is common, and critical events were captured in 8.8% of patients. The majority of patients with critical events underwent treatment. Factors associated with critical events include EPs as ordering providers, complex CHD, and cardiomyopathy.

Pulsed Field Ablation to Treat Paroxysmal Atrial Fibrillation: Safety and Effectiveness in the AdmIRE Pivotal Trial.

Evidence from clinical trials of early pulsed field ablation (PFA) systems in treating atrial fibrillation has demonstrated their promising potential to reduce complications associated with conventional thermal modalities while maintaining efficacy. However, the lack of a fully integrated mapping system, a staple technology of most modern electrophysiology procedures, poses limitations in lesion creation and workflow options. A novel variable-loop PFA catheter integrated with an electroanatomic mapping system has been developed that allows for real-time nonfluoroscopic procedural guidance and lesion indexing as well as feedback of tissue-to-catheter proximity. AdmIRE (Assessment of Safety and Effectiveness in Treatment Management of Atrial Fibrillation With the Bosense-Webster Irreversible Electroporation Ablation System), a multicenter, single-arm, Food and Drug Administration investigational device exemption study, evaluated the long-term safety and effectiveness of this integrated PFA system in a large United States-based drug-refractory symptomatic paroxysmal atrial fibrillation patient population. Using the PFA catheter with a compatible electroanatomic mapping system, patients with drug-refractory symptomatic paroxysmal atrial fibrillation underwent pulmonary vein isolation. The primary safety end point was primary adverse event within 7 days of ablation. The primary effectiveness end point was a composite end point that included 12-month freedom from documented atrial tachyarrhythmia (ie, atrial fibrillation, atrial tachycardia, atrial flutter) episodes, failure to achieve pulmonary vein isolation, use of a nonstudy catheter for pulmonary vein isolation, repeat procedure (except for one redo during blanking), taking a new or previously failed class I or III antiarrhythmic drug at higher dose after blanking, or direct current cardioversion after blanking. At 30 centers, 277 patients with paroxysmal atrial fibrillation (61.5±10.3 years of age; 64.3% male) in the pivotal cohort underwent PFA. More than 25% of the procedures were performed without fluoroscopy. Median (Q1, Q3) pulmonary vein isolation procedure, fluoroscopy, and transpired PFA application times were 81.0 (61.0, 112.0), 7.1 (0.00, 14.3), and 31.0 (24.8, 40.9) minutes, respectively. The primary adverse event rate was 2.9% (8 of 272), with the most common complication being pericardial tamponade. The 12-month primary effectiveness end point was 74.6%. The 1-year freedom from atrial fibrillation, atrial tachycardia, or atrial flutter recurrence rate after blanking was 75.4%. Substantial improvements in quality of life were observed as early as 3 months after the procedure, concurrent with a reduction in multiple health care use measures. AdmIRE confirmed the safety and effectiveness of the variable-loop PFA catheter, with short procedure and PFA application times and low fluoroscopy exposure. URL: https://www.clinicaltrials.gov; Unique identifier: NCT05293639.

Fabry disease in female monozygotic twins with complex intronic haplotype variants: a case report

BackgroundFabry disease is an X-linked lysosomal storage disease caused by the impairment of α-galactosidase A. The complex intronic haplotype (CIH) variants, located in promoter and intronic regulatory lesions, has been found in patients with classical forms of Fabry disease. We present a case of Fabry disease in female monozygotic twins exhibiting the CIH mutation and classical manifestations.Case presentationA 61-year-old woman with a history of stroke, carotid artery occlusion, hypertrophic cardiomyopathy, and chronic kidney disease was referred to the nephrology clinic for management of her chronic kidney disease. Her monozygotic twin sister also presented with hypertrophic cardiomyopathy, atrial flutter, carotid stenosis, and proteinuria. Clinical symptoms and a comprehensive family history strongly suggested the presence of Fabry disease. Genetic analysis revealed the presence of 5 variants within a complex intronic haplotype (CIH): c.−10 C > T, c.369 + 990 C > A, c.370 − 81_370–77delCAGCC, c.640–16 A > G, and c.1000–22 C > T. We conducted a review of the patient’s previous kidney biopsy findings, which demonstrated the presence of lamellated inclusion bodies in electron microscopy. Remarkably, both the monozygotic twin sister and her son exhibited the same genetic mutation. Enzyme replacement therapy was initiated for the patient. Her kidney function decreased throughout a thorough 2-year follow-up period, while there was a slight decrease in the left ventricular mass index.ConclusionsThis is the first reported case of female monozygotic twins with the CIH variants representing cardiac, cerebrovascular, and renal manifestations suggestive of Fabry disease.

Invasive management of atrial tachycardias using a novel lattice-tip catheter combining high-density mapping and dual ablation properties: initial real-world experience.

Invasive management of atrial tachycardias(ATs) requires proper diagnosis of the mechanism followed by elimination of the responsible substrate. A novel lattice-tip catheter with both high-density mapping and dual ablation properties(radiofrequency-RF/pulsed field ablation-PFA) has been recently introduced for catheter ablation of atrial fibrillation. We present the first study to assess its performance in the management of ATs (diagnostic and therapeutic). Patients with documented ATs were selected. Activation mapping was used for the establishment of the AT mechanism. Confirmation with entrainment was performed, whenever appropriate. Accuracy of the activation mapping in diagnosis, acute ablation efficacy, and procedural characteristics were the study endpoints. Twenty patients were included (12 cavotricuspid isthmus-dependent atrial flutters, 5 mitral flutters, 2 roof flutters, and 2 focal ATs). Proper diagnosis was established by activation mapping in all cases. The mean mapping time was 7.85 ± 3.06 min with 296.82 ± 150.9 mean mapping points/minute. The mean ablation time was 54.25 ± 42.97 s. Conversion to sinus rhythm during ablation was achieved in all cases with the exception of a roof flutter that converted to mitral flutter and a case of a parahisian AT in which ablation was not attempted. Patients that received ablation did not experience any arrhythmia recurrence in a mean follow up of 4.14 ± 0.91months. No major or minor complications occurred. The lattice-tip catheter and its dedicated electroanatomical mapping system provided sufficiently detailed activation mapping for the diagnosis of the AT mechanism. The delivered lesions were highly effective acutely, with no adverse events. However, limitations exist and should be acknowledged.

Exploring Inflammatory Markers and Risk Factors Associated with Pericarditis Development after Ablation for Atrial Fibrillation.

Background: This study aimed to explore the association between inflammatory markers and the occurrence of post-atrial fibrillation (AF) ablation pericarditis (PAP), while also examining the PAP's incidence and contributing factors. Methods: A retrospective cohort study was conducted between January 2021 and November 2023, including patients who underwent successful AF ablation. Inflammatory markers of interest included the systemic immune-inflammation index (SII), the neutrophil-to-lymphocyte ratio (NLR), and the platelet-to-lymphocyte ratio (PLR). Results: Among the 231 patients examined, 22 (9.52%) were classified as suspected PAP, and 14 (6.06%) as definitive PAP. The median age was 58 years, with no age difference between groups. Males comprised 51.52% of the sample, with male sex frequency significantly higher in the suspected PAP group relative to the other groups (p = 0.007). Multivariable logistic regression indicated that AF duration (p = 0.026) and cavotricuspid isthmus (CTI) ablation (p = 0.001) were associated with definitive PAP, whereas analysis for any pericarditis (suspected or definitive PAP) revealed independent relationships with CTI ablation (p = 0.003) and sleep apnea (p = 0.008). SII, NLR, and PLR were not associated with PAP. Conclusions: Prolonged AF duration, CTI ablation, and sleep apnea are risk factors for PAP. The inflammatory markers (SII, NLR, and PLR) showed no association, warranting further investigation into other markers.

Uric acid levels and cardiovascular and cerebrovascular diseases: a Mendelian randomization study.

The relationship between uric acid (UA) levels and cardiovascular and cerebrovascular diseases (CCVD) is controversial. A two-sample Mendelian randomization (MR) study was conducted to explore the causal effects of UA levels on CCVD. Genetic variants strongly associated with UA levels were selected as instrumental variables from the Genome-Wide Association Study (GWAS) dataset. The GWAS data, sourced from the Global Urate Genetics Consortium (GUGC), comprised a sample size of 110,347 individuals. The selected CCVD outcomes included stroke, coronary artery disease (CAD), as well as atrial fibrillation and flutter. The primary analytical approach employed the inverse-variance weighted (IVW) method, supplemented by MR-Egger and weighted median as complementary methods. Sensitivity analysis was performed to test heterogeneity and pleiotropy. The MR analysis results indicated a causal association between UA levels and stroke (OR: 1.002; 95% CI: 1.000-1.003; p = 0.036), CAD (OR: 1.118; 95% CI: 1.044-1.197; p = 0.001), as well as atrial fibrillation and flutter (OR: 1.141; 95% CI: 1.037- 1.256; p = 0.007). The results of MR-Egger and weighted median methods confirmed the direction of the IVW results, enhancing the robustness of the findings. No significant anomalies were detected in the sensitivity analysis. The MR study suggests that UA levels exert causal effects on stroke, CAD, as well as atrial fibrillation and flutter.

Recurrent atrial flutter after radiofrequency ablation for atrial fibrillation in a patient with hypertrophic obstructive cardiomyopathy undergoing repetitive transcoronary ablation of septal hypertrophy

IntroductionWe described the clinical characteristics of a patient with hypertrophic obstructive cardiomyopathy (HOCM) who had undergone transcoronary ablation of septal hypertrophy (TASH) twice and developed atrial flutter after radiofrequency ablation for atrial fibrillation (AF) due to pulmonary vein reconnection. This case of HOCM is unique because of its complex complications and multiple complex atrial arrhythmias. The treatment of HOCM was successful and the postoperative follow-up results was good.Methods and resultsA 71-year-oldfemale, developed exertional dyspnea with palpitations 12 years ago, with a valid diagnosis of HOCM according to the echocardiography which showed an absolute increase in the interventricular septum thickness (22.8 mm). She underwent two rounds of TASH and only the second round was successful. During a visit due to recurrent palpitations, the patient was diagnosed with AF based on electrocardiographic examination. Circumferential pulmonary vein isolation (CPVI) was performed to treat AF. However, the recurrence of atrial flutter was detected on her electrocardiograms (ECGs) three years after the operation. Since the patient had an interstitial lung injury, there were relative contraindications for antiarrhythmic drugs. Due to restrictive use of antiarrhythmic drugs and continuous palpitation, the patient agreed to receive a second radiofrequency ablation. Left-sided macroreentrant circuits were identified via high-density mapping and successful ablation was performed at the isthmus.ConclusionsPerforming catheter ablation and TASH respectively in patients with HOCM associated with AF would be tricky. But taking such a comprehensive and respective clinical treatment would be beneficial to patients in the long term.

Real world effectiveness of Hawthorn special extract WS 1442 in a retrospective cohort study from Germany

Hawthorn special extract WS 1442 has beneficial effects on the cardiovascular system. Experimental studies have shown an antiarrhythmic effect of the substance. In the present study, we investigated antiarrhythmic effects of WS 1442 compared with magnesium/potassium in a large collective of outpatients. Using the IQVIA Disease Analyzer (DA) database, we included 4550 patients with a prescription of WS 1442 and 4550 matched patients with Tromcardin prescriptions (all registered products under the trademark Tromcardin that are magnesium and potassium supplementing foods for special medical purposes) who were followed for 5 years after the index date. The incidence of various cardiac arrhythmias (atrial fibrillation and flutter (AFF), tachycardia, and other cardiac arrhythmias) was recorded. Cox regression models were used to evaluate the potential association between both drugs and arrhythmias. The cumulative incidence of atrial fibrillation and flutter was significantly lower among patients with a prescription of WS 1442 compared to patients with magnesium/potassium prescriptions (10.8% vs. 16.4%, p < 0.001). WS 1442 prescription was significantly associated with a lower incidence of atrial fibrillation and flutter compared to magnesium/potassium (HR 0.71; 95% CI 0.64–0.80; p < 0.001). The cumulative incidence of tachycardia was significantly lower in the WS 1442 group compared to the magnesium/potassium group (8.3% vs. 9.4%, p < 0.001), similarly, the cumulative incidence of other cardiac arrhythmias was significantly lower among patients with WS 1442 compared to patients with magnesium/potassium (10.2% vs. 14.8%, p < 0.001). This study showed that in a large collective of outpatients, intake of hawthorn special extract WS 1442 was associated with a significantly lower incidence of atrial fibrillation, tachycardia, and other cardiac arrhythmias compared to magnesium/potassium, indicating its potential in treating and preventing such conditions.

Dofetilide for the treatment of premature ventricular complexes and ventricular tachycardia in patients with structural heart disease.

Dofetilide is a class III antiarrhythmic agent approved for the treatment of atrial fibrillation and atrial flutter. Given the efficacy of other class III agents, it has been used off-label for the treatment of premature ventricular complexes (PVCs) and ventricular tachycardias (VTs). The purpose of this study was to determine the efficacy and safety of dofetilide for ventricular arrythmias (VAs). In this retrospective cohort study, 81 patients (59 men; age = 60 ± 14 years; LVEF = 0.34 ± 0.16) were admitted for dofetilide initiation to treat PVCs (29), VTs (42) or both (10). A ≥ 80% decrease in PVC burden was defined as a satisfactory response. An ICD was present in 72 patients (89%). Another antiarrhythmic was previously used in 50 patients (62%). Prior catheter ablation had been performed in 33 patients (41%). During intitiation, dofetilide was discontinued in 12 patients (15%) due to QT prolongation (8) and inefficacy to suppress VAs (4). Among the 32 patients with PVCs who successfully started dofetilide, the mean PVC burden decreased from 20 ± 10% to 8 ± 8% at a median follow-up of 2.6 months (p < .001). PVC burden was reduced by ≥80% in only 11/32 patients (34%). During 7 ± 1 years of follow-up, 41/69 patients (59%) continued to have VAs and received appropriate ICD therapies for monomorphic VTs (35) and polymorphic VT/VF (6) at a median of 8.0 (IQR 2.6-33.2) months. Dofetilide had to be discontinued in 50/69 patients (72%) due to inefficacy or intolerance. The composite outcome of VT/VF recurrence, heart transplantation, or death occurred in 6/12 patients (50%) without dofetilide and 49/69 patients (71%) with dofetilide. The event free survival was similar between patients treated with and without dofetilide (log-rank p = .55). Treatment with dofetilide was associated with a decrease in PVCs, however clinically significant suppression occurred in a minority of patients. Dofetilide failed to suppress the occurrence of VTs in a majority of patients.

Cavotricuspid isthmus ablation using a pentaspline pulsed field ablation catheter: feasibility and acute results.

Cavotricuspid isthmus ablation using a pentaspline pulsed field ablation catheter: feasibility and acute results.

Atrial flutter and sick sinus syndrome

BackgroundSick sinus syndrome (SSS) is a common condition resulting in reduced quality of life, syncope, and permanent pacemaker (PPM) implantation, but predictors have not been elucidated. Whereas atrial arrhythmias are frequently associated with SSS, we hypothesized that atrial flutter (AFL) would strongly predict SSS, given shared relationships with right atrial and particularly crista terminalis fibrosis. ObjectiveThe study aimed to assess the impact of AFL on the occurrence of SSS and associated syncope and PPM implantation. MethodsHealth care databases were used to identify adults aged ≥18 years receiving hospital-based care in California in 2005–2019. International Classification of Diseases codes were used to identify diagnoses and procedures. Patients were classified on the basis of the presence of AFL and atrial fibrillation (AF). Cox proportional hazards models adjusting for demographics and comorbidities were employed. ResultsWe included 29,357,609 individuals (54% female; mean age, 46 years), 101,243 with AFL alone, 1,674,680 with AF alone, and 284,547 with AF and AFL. After adjustment for age, sex, race and ethnicity, and comorbidities, AF, AFL, and both arrhythmias were each associated with increased risk of SSS and associated syncope and PPM implantation (all P < .001). In the population with AF, an additional AFL diagnosis conferred a higher risk for development of SSS (hazard ratio [HR],1.62; 95% confidence interval, 1.59–1.64), syncope (HR, 1.63; 1.54–1.72), and PPM implantation (HR, 1.74; 1.70–1.79). ConclusionAFL is associated with an increased risk of incident SSS and its adverse consequences, especially in patients with coexisting AF. AFL may be useful for risk stratification strategies to predict, to prevent, and to treat SSS.

Sinoatrial node function and the role of sinoatrial conduction in the typical atrial flutter substrate

BackgroundSinoatrial node (SAN) activation and sinoatrial conduction pathways (SACPs) have been assessed in animals but not in humans. ObjectivesWe used ultrahigh-density mapping and simulated models to characterize the SAN and to investigate whether slowed SAN conduction may contribute to the atrial flutter (AFL) substrate. MethodsTwenty-seven patients undergoing electrophysiologic procedures had right atrial mapping. SAN activation patterns and conduction block were analyzed. The interaction between the SAN and the intercaval line of block (LOB) was analyzed, and right atrial simulations with different degrees of block were created to investigate arrhythmia mechanisms. ResultsFifteen AFL patients and 12 reference patients were enrolled. SACPs were identified in all patients with sinus rhythm maps. An SAN-adjacent LOB was observed in AFL patients. SAN conduction velocity was slower in AFL vs reference (0.60 m/s [0.56–0.78 m/s] vs 1.13 m/s [1.00–1.21 m/s]; P = .0021). Coronary sinus paced maps displayed an intercaval LOB in AFL patients but not in reference patients, which was completed superiorly by the SAN-adjacent LOB. Corrected sinus node recovery time was longer in AFL patients (552.3 ± 182.9 ms vs 325.4 ± 138.3 ms; P < .006) and correlated with degree of intercaval block (r = 0.7236; P = .0003). Computer modeling supported an important role of SAN-associated block in the flutter substrate. ConclusionUltrahigh-density mapping accurately identifies SAN activation and SACPs. The LOB important for typical AFL was longer in AFL patients, and when partial, it was always present inferiorly and completed superiorly because of slowed conduction across the SAN. Corrected sinus node recovery time correlated with intercaval block, suggesting a role for SAN disease in the genesis of the typical AFL substrate.

Epidemiology of major heart rhythm and conduction disorders

BackgroundHeart rhythm and conduction disorders cover a variety of pathologies, ranging from the benign to the immediately life threatening. AimsTo describe the epidemiology of patients hospitalized for arrhythmias in France, and to estimate the prevalence and mortality associated with these disorders, divided into three separate groups: atrial fibrillation and flutter; conduction disorders; and ventricular tachycardia/cardiac arrest. MethodsWe looked in the National Health Data System and selected patients who had been hospitalized at least once in 2022 for these diseases and patients who died as a result of these diseases in 2021. The prevalence of these disorders among people alive on 1st January 2023 was estimated by combining previous hospitalizations and people in receipt of 100% coverage for a registered long-term disease. ResultsAt 1st January 2023, the prevalence of patients who had been hospitalized with major rhythm and conduction disorders was 2,740,141: 2,027,900 with atrial fibrillation/flutter; 999,692 with conduction disorders; and 214,989 with ventricular tachycardia/cardiac arrest. In 2022, respectively 90,502, 48,268 and 16,930 were hospitalized for these conditions, which equate to rates of 169.5, 68.3, and 31.7 per 100,000 inhabitants, respectively. Several departments in the Hauts-de-France and Grand-Est regions had rates>20% above the national rate. The rate of ventricular tachycardia/cardiac arrest was 40% higher among residents of the most deprived municipalities than among residents of the least deprived municipalities. Mortality at the end of hospitalization reached 44% for patients hospitalized for ventricular tachycardia/cardiac arrest. ConclusionsArrhythmias and conduction disorders affect a significant proportion of the population, leading to a large number of hospitalizations and procedures, particularly ablation techniques and pacemaker/defibrillator implantation. Given the extent of regional disparities and the impact of the socioeconomic status of the municipality of residence, targeted prevention and screening strategies should be implemented.

Burden of cardiovascular disease among the Western Pacific region and its association with human resources for health, 1990–2021: a systematic analysis of the Global Burden of Disease Study 2021

A comprehensive profile of cardiovascular disease (CVD) burden and human resources for health (HRH) distribution in the WHO Western Pacific region has yet to be presented. Studies on the relationship between HRH and CVD in this region are limited. We aimed to describe CVD trends and HRH density in the Western Pacific region and explore the association of HRH with CVD burden. Estimates of CVD deaths and disability-adjusted life years (DALYs) were obtained from the Global Burden of Disease Study (GBD) 2021, and the annual density of HRH was retrieved from GBD 2019. We presented trends in CVD burden and HRH density across 31 Western Pacific countries. Spearman rank correlation analysis and generalized linear models were used to examine associations between CVD burden and HRH density. In 2021, CVD caused six million deaths and 125 million DALYs in the Western Pacific region, accounting for 39.4% and 22.5% of all-cause deaths and DALYs. From 1990 to 2021, the number of CVD deaths and DALYs increased by 94.9% and 57.3% in this region, whereas the age-standardized rate of CVD deaths and DALYs declined in all countries. In 2021, stroke and ischemic heart disease were the leading causes in the Western Pacific region, and a 32-year increase in CVD burden was primarily driven by aortic aneurysm, lower extremity peripheral arterial disease, endocarditis, and atrial fibrillation and flutter. In 2019, there was an approximately 20-fold difference in HRH density across 31 countries from the lowest in Papua New Guinea to the highest in Australia. HRH density was negatively related to the age-standardized rate of CVD deaths (r s =-0.74) and DALYs (r s =-0.73), especially strong associations between CVD burden and the density of dentistry personnel, aides & emergency medical workers, and medical laboratory technicians. CVD remains a pressing public health issue in the Western Pacific region where noticeable shortages in health workers exist. The negative associations between CVD burden and HRH density suggest that health workers, especially dentistry personnel, aides & emergency medical staff, and medical laboratory technicians merit more investment to reduce the CVD burden. National Natural Science Foundation of China (82073573 to ZZ; 82273654 to YS).

Multielectrode catheter-based pulsed field ablation of persistent and long-standing persistent atrial fibrillation.

Rhythm control of non-paroxysmal atrial fibrillation (AF) is significantly more challenging, as a result of arrhythmia perpetuation promoting atrial substrate changes and AF maintenance. We describe a tailored ablation strategy targeting multiple left atrial (LA) sites via a pentaspline pulsed field ablation (PFA) catheter in persistent AF sustained beyond 6 months (PerAF > 6 m) and long-standing persistent AF (LSPAF). The ablation protocol included the following stages: pulmonary vein antral and posterior wall isolation plus anterior roof line ablation (Stage 1); electrogram-guided substrate ablation (Stage 2); atrial tachyarrhythmia regionalization and ablation (Stage 3). Seventy-two [age:68 ± 10years, 61.1%males; AF history: 25 (18-45) months] patients with PerAF > 6 m (52.8%) and LSPAF (47.2%) underwent their first PFA via the FarapulseTM system. LA substrate ablation (Stage 1 and 2) led to AF termination in 95.8% of patients. AF organized into a left-sided atrial flutter (AFlu) in 46 (74.2%) patients. The PFA catheter was used to identify LA sites showing diastolic, low-voltage electrograms and entrainment from its splines was performed to confirm the pacing site was inside the AFlu circuit. Left AFlu termination was achieved in all cases via PFA delivery. Total procedural and LA dwell times were 112 ± 25 min and 59 ± 22 min, respectively. Major complications occurred in 2 (2.8%) patients. Single-procedure success rate was 74.6% after 14.9 ± 2.7 months of follow-up; AF-free survival was 89.2%. In our cohort, PFA-based AF substrate ablation led to AF termination in 95.8% of cases. Very favourable clinical outcomes were observed during >1 year of follow-up.

Evaluation of posterior mitral isthmus ablation in the absence of a vein of Marshall.

Achieving acute and durable mitral isthmus (MI) block remains challenging using radio frequency (RF)-catheter ablation alone. Vein of Marshall (VoM) ethanolisation results in chemical damage along the mitral isthmus resulting in the creation of a durable transmural lesion with a very high rate of procedural block. However, no studies have systematically assessed the efficacy of MI ablation alone when no anatomical VoM is present. Thirty seven patients without VoM evidenced after careful angiographic examination were included. Ablation parameters and result were compared to a matched control group in whom the posterior MI line was performed without assessing the presence of the VoM. MI block was achieved in 36 out of 37 patients without VoM (97%), with endocardial ablation only in 5/37 (14%) and combined endocardial and CS ablation in 32/37 patients (86%). There was a significant difference in occurrence of block between patients without a VoM and the control group (97,3% vs. 65% respectively, p<0,01), with a trend towards less needed RF (26 (IQR 20-38) vs 29 (IQR 19-40) tags (p=0.8), 611 (IQR 443-805) vs 746 (IQR 484-1193) seconds (p=0.08)). The absence of a Vein of Marshall is associated with a very high rate of procedural block during posterior mitral isthmus ablation. The higher rate of MI block in this specific population would also suggest the crucial role of the Vein of Marshall (when present) in resistant MI block.

Air pollution below US regulatory standards and cardiovascular diseases using a double negative control approach

Growing evidence suggests that long-term air pollution exposure is a risk factor for cardiovascular mortality and morbidity. However, few studies have investigated air pollution below current regulatory limits, and causal evidence is limited. We use a double negative control approach to examine the association between long-term exposure to air pollution at low concentration and cardiovascular hospitalizations among US Medicare beneficiaries aged ≥65 years between 2000 and 2016. The expected values of the negative outcome control (preceding-year hospitalizations) regressed on exposure and negative exposure control (subsequent-year exposure) are treated as a surrogate for omitted confounders. With analyses separately restricted to low-pollution areas (PM2.5 < 9 μg/m³, NO2 < 75.2 µg/m3 [40 ppb], warm-season O3 < 88.2 μg/m3 [45 ppb]), we observed positive associations of the three pollutants with hospitalization rates of stroke, heart failure, and atrial fibrillation and flutter. The associations generally persisted in demographic subgroups. Stricter national air quality standards should be considered.

Ablation of Supraventricular Arrhythmias With as Low as Reasonably Achievable X-Ray exposure (AALARA): Results of Prospective, Observational, Multicenter, Multinational, Open-Label Registry Study on Real World Data Using Routine Ensite 3D Mapping During SVT Ablation.

The reduction of fluoroscopic exposure during catheter ablation of supraventricular arrhythmias is widely adopted by experienced electrophysiology physicians with a relatively short learning curve and is becoming the standard of care in many parts of the world. While observational studies in the United States and some parts of Western Europe have evaluated the minimal fluoroscopic approach, there are scarce real-world data for this technique and the generalizability of outcomes in other economic regions. The AALARA study is a prospective, observational, multicenter, and multinational open-label study. Patients were recruited from 13 countries across Central Eastern Europe, North and South Africa, the Middle East, and the CIS (Commonwealth of Independent States), with different levels of operator expertise using minimal fluoroscopic exposure techniques. Data on radiation exposure, procedural success, complications, recurrence, and quality of life changes were collected and analyzed. A total of 680 patients were enrolled and followed for 6 months. The majority were ablation naïve with the commonest arrhythmia ablated being typical AVNRT (58%) followed by Atrial Flutter (23%). Zero fluoroscopy exposure was observed in almost 90% of the cases. Fluoroscopy was most commonly used during the ablation phase of the procedure. We observed a high acute success rate (99%), a low complication rate (0.4%), and a 6-month recurrence rate of 3.8%. There was a significant improvement in the patient's symptoms and quality of life as measured by patient global assessment. The routine use of a 3D mapping system during right-sided ablation was associated with low radiation exposure and associated with high acute success rate, low complications, and recurrence rate along with significant improvement in quality of life. The data confirm the reproducibility of this approach in real-world settings across different healthcare systems, and operator experience supporting this approach to minimize radiation exposure without compromising efficacy and safety. NCT04716270.

Mechanistic Insights into Roof-Dependent Macroreentrant Atrial Flutter with Endocardial Block of the Roof Line: A Case Report

Background: Epicardial roof-dependent atrial tachycardia is rare among macroreentrant tachycardias. The importance of epicardial structure or fiber involving septopulmonary bundle (SPB) has not been realized generally. Case presentation: A 74-year-old woman who underwent catheter ablation of atrial fibrillation previously accepted a second-time radiofrequency ablation due to atrial flutter. The mapping and entrainment results of the tachycardia tended to be an epicardial SPB-dependent macroreentrant atrial tachycardia and it was ablated to sinus rate at the first single targeting site, just located in the breakout site of SPB into the posterior wall (PW) of left atrial (LA). The twice-activation mapping of PW of LA also proved the presence of SPB. No recurrent arrhythmia was seen at follow-up at 3 months. Conclusion: In this case, an uncommon phenomenon was observed post-ablation for persistent atrial fibrillation, where the epicardial muscular structure of the LA-SPB was involved in atypical atrial flutter. This should be considered as a potential factor in such cases. Further similar cases may be required to improve diagnostic accuracy and to formulate effective ablation strategies for this type of tachycardia.