Risk assessment of esophageal ulceration following left atrial radiofrequency linear ablation.

INTRODUCTION: Esophageal safety following radiofrequency (RF) left atrial (LA) linear ablation has not been established. To determine the esophageal safety profile of LA linear RF lesions, we performed systematic esophagogastroduodenoscopy in all patients with intraesophageal temperature rise (ITR) ≥ 38.5°C. METHODS AND RESULTS: Between December 2021 and July 2023, a total of 200 consecutive patients with atrial tachyarrhythmia (ATA) underwent linear ablation with posterior dome (roof or floor) or posterior mitral isthmus line transection. Patients with ITR ≥ 38.5°C were scheduled for esophageal endoscopy ~3 weeks after ablation. Patient and ATA characteristics, procedural parameters, endoscopy findings and ablation lesion data were collected and analyzed. One hundred thirty-three out of 200 (67%) patients showed ITR ≥ 38.5°C during LA linear ablation. ITR (with maximal temperature of 45.7°C) was more frequently observed during floor line ablation (82% of cases). ITR was less observed during roof line ablation (34%) and posterior mitral isthmus ablation (4%). Endoscopy, performed in 115 patients after 24 ± 10 days, showed esophageal ulceration in four patients (two patients Kansas City classification [KCC] 2a and two patients KCC 2b). No patient showed esophageal perforation or fistula. CONCLUSION: Temperature rise during LA linear ablation is frequent and ulceration risk exists, particularly when floor line is performed. Safety measures are needed to avoid potential severe complications like esophageal perforation and fistula.

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

AIMS: Achieving acute and durable mitral isthmus (MI) block remains challenging using radiofrequency (RF) catheter ablation alone. Vein of Marshall (VoM) ethanolization results in chemical damage along the MI 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. METHODS AND RESULTS: Thirty seven patients without VoM evidenced after careful angiographic examination were included. Ablation parameters and result were compared with a matched control group in whom the posterior MI line was performed without assessing the presence of the VoM. Mitral isthmus block was achieved in 36 out of 37 patients without VoM (97%), with endocardial ablation only in 5/37 (14%) and combined endocardial and coronary sinus ablation in 32/37 patients (86%). There was a significant difference in the 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 [interquartile range (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]}. CONCLUSION: The absence of a VoM is associated with a very high rate of procedural block during posterior MI ablation. The higher rate of MI block in this specific population would also suggest the crucial role of the VoM (when present) in resistant MI block.

Catheter Ablation of Persistent AF-Where are We Now?

Persistent atrial fibrillation (AF) is a diverse condition that includes various subtypes and underlying causes of arrhythmia. Progress made in catheter ablation technology in recent years has significantly enhanced the durability of ablation. Despite these advances however, the effectiveness of ablation in treating persistent AF is still relatively modest. Studies exploring the mechanisms behind persistent AF have identified substrate-driven focal and re-entrant sources within the atrial body as crucial in sustaining AF among individuals with persistent AF. Furthermore, the widespread adoption of atrial late gadolinium enhancement cardiac magnetic resonance (CMR) imaging and the ongoing refinement of invasive voltage mapping techniques have allowed for detailed assessment of fibrotic remodelling prior to or at the time of procedure. Translation into clinical practice, however, has yielded overall disappointing results. The clinical application of AF mapping in ablation procedures has not shown any substantial advantages beyond the use of pulmonary vein isolation (PVI) alone and adjunct ablation of fibrotic areas has yielded conflicting results in recent randomized trials. The emergence of pulsed field ablation represents a welcome development in the field and several studies have demonstrated an enhanced safety profile and increased procedural efficiency with this non-thermal energy modality. Pulsed field ablation also holds promise for safe and efficient substrate ablation beyond the pulmonary veins, but further trials are needed to assess its impact on longer term success rates. Continued advancements in our comprehension of AF mechanisms, alongside ongoing developments in catheter technology aimed at safe formation of transmural lesions, are essential for achieving better clinical outcomes for patients with persistent AF.

Vein of Marshall Ethanol Infusion for AF Ablation; A Review.

The outcomes of persistent atrial fibrillation (AF) ablation are modest with various adjunctive strategies beyond pulmonary vein isolation (PVI) yielding largely disappointing results in randomised controlled trials. Linear ablation is a commonly employed adjunct strategy but is limited by difficulty in achieving durable bidirectional block, particularly at the mitral isthmus. Epicardial connections play a role in AF initiation and perpetuation. The ligament of Marshall has been implicated as a source of AF triggers and is known to harbour sympathetic and parasympathetic nerve fibres that contribute to AF perpetuation. Ethanol infusion into the Vein of Marshall, a remnant of the superior vena cava and key component of the ligament of Marshall, may eliminate these AF triggers and can facilitate the ease of obtaining durable mitral isthmus block. While early trials have demonstrated the potential of Vein of Marshall 'ethanolisation' to reduce arrhythmia recurrence after persistent AF ablation, further randomised trials are needed to fully determine the potential long-term outcome benefits afforded by this technique.

Procedural performance and outcome after pulsed field ablation for pulmonary vein isolation: comparison with a reference radiofrequency database.

Aims: Pulsed field ablation (PFA) is a promising ablation technique for pulmonary vein isolation (PVI) with appealing advantages over radiofrequency (RF) including speed, tissue selectivity, and the promise of enhanced durability. In this study, we determine the procedural performance, efficacy, safety, and durability of PFA and compare its performance with a dataset of optimized RF ablation. Methods and results: After propensity score matching, we compared 161 patients who received optimized RF-guided PVI in the PowerPlus study (CLOSE protocol) with 161 patients undergoing PFA-guided PVI for paroxysmal or persistent atrial fibrillation (AF; pentaspline basket catheter). The median age was 65 years with 78% paroxysmal AF in the PFA group (comparable characteristics in the RF group). Pulsed field ablation-guided PVI was obtained in all patients with a procedure time of 47 min (vs. 71 min in RF, P < 0.0001) and a fluoroscopy time of 15 min (vs. 11 min in RF, P < 0.0001). One serious adverse event [transient ischaemic attack] occurred in a patient with thrombocytosis (0.6 vs. 0% in RF). During the 6-month follow-up, 24 and 27 patients experienced a recurrence with 20 and 11 repeat procedures in the PFA and the RF groups, respectively (P = 0.6 and 0.09). High-density mapping revealed a status of 4 isolated veins in 7/20 patients in the PFA group and in 2/11 patients in the RF group (35 vs. 18%, P = 0.3). Conclusion: Pulsed field ablation fulfils the promise of offering a short and safe PVI procedure, even when compared with optimized RF in experienced hands. Pulmonary vein reconnection is the dominant cause of recurrence and tempers the expectation of a high durability rate with PFA.

Early atrial fibrillation recurrence post catheter ablation: Analysis from insertable cardiac monitor in the era of optimized radiofrequency ablation.

BACKGROUND: Early recurrence of atrial tachyarrhythmia (ERAT) is associated with ablation-induced proarrhythmogenic inflammation; however, existing studies used intermittent monitoring or nonoptimized radiofrequency (RF) applications (noncontiguous or without ablation index target value). OBJECTIVE: The purpose of this study was to investigate the relationship between ERAT and late recurrence based on insertable cardiac monitor (ICM) data. METHODS: We compiled data from Close-To-Cure and Close Maze studies, which enrolled patients who underwent RF ablation for paroxysmal or persistent atrial fibrillation (AF). All patients were implanted with an ICM 2-3 months before ablation. RESULTS: We studied 165 patients (104 with paroxysmal AF, 61 with persistent AF). Over the 1-year follow-up period, 41 of the patients experienced late recurrence. The risk of late recurrence was higher in patients experiencing ERAT (hazard ratio [HR] 6.2; 95% confidence interval [CI] 3.0-13.0), with negative and positive predictive values of 90.5% and 45.7%, respectively. Median burden of AF during the blanking period was significantly higher in patients with late recurrence (7.9% [0.0%-99.6%]) compared to those without recurrence (0.0% [0.0%-6.0]; P <.001). For each 1% increase in AF burden during the blanking period, late recurrence increased by 4.6% (HR 1.046; 95% CI 1.035-1.059). The best tradeoff for predicting AF from ERAT occurrence was AF burden of 0.6% and last ERAT at 64 days. CONCLUSION: In patients ablated for paroxysmal and persistent AF with a durable RF lesion set and implanted with a continuous monitoring device, postablation early AF recurrence and burden significantly predict late recurrence. The post-AF ablation blanking period should be reduced to 2 months.

Atrial Topology for a Unified Understanding of Typical and Atypical Flutter.

BACKGROUND: Macroreentry stands as the predominant mechanism of typical and atypical flutter. Despite advances in mapping, many aspects of macroreentrant atrial tachycardia remain unsolved. In this translational study, we applied principles of topology to understand the activation patterns, entrainment characteristics, and ablation responses in a large clinical macroreentrant atrial tachycardia database. METHODS: Because the atrium can be topologically seen as a closed sphere with holes, we used a computational fixed spherical mesh model with a finite number of holes to induce and analyze macroreentrant atrial tachycardia. The ensuing insights were used to interpret high-density activation maps, postpacing interval-tachycardia cycle length values (difference between postpacing interval and tachycardia cycle length), and ablation response in 131 cases of typical and atypical flutter (n=106 left atrium, n=25 right atrium). RESULTS: Modeling of macroreentrant atrial tachycardia revealed that reentry on closed surfaces consistently manifests itself as paired rotation and that an odd number of critical boundaries is mathematically impossible. Together with mathematical confirmation by the index theorem, this led to a unifying construct that could explain the number of loops, difference between postpacing interval and tachycardia cycle length values, and ablation outcomes (termination, no change, or prolongation in tachycardia cycle length) in all 131 cases. CONCLUSIONS: Combining topology with the index theorem offers a novel and cohesive framework for understanding and managing typical and atypical flutter.

Changes in lipid lowering medication and lipid levels over time in patients with stable coronary artery disease.

BACKGROUND/AIM: To provide longitudinal data on the evolution of lipid levels and the intake of lipid-lowering therapies in patients with stable coronary artery disease. METHODS: Single-centre retrospective study with inclusion of 350 patients with a first coronary artery event in 2014 or earlier and outpatient cardiac clinic follow-up in 2015 and 2019. Lipid levels were collected within a time frame of 3 months of their visits.This retrospective study protocol (2020.086) was approved by the ethical committee and by the Data Privacy Officer of AZ Maria Middelares Ghent. For this type of study, formal consent is not required, following local law and regulations. RESULTS: Average LDL levels were 82 (±26) mg/dl in 2015 and 70 (±24) mg/dl in 2019 (p < 0.001). Most patients included were already on statin treatment before inclusion in the trial (94%), with a significant increase in high-intensity statin use (45% vs. 58%) after a 5-year follow-up. At the same time, we observed a significant increase in ezetimibe use (in combination with statin therapy or in monotherapy) (8% vs. 22%) during follow-up. LDL ≤70 mg/dl was 34% in 2015 and 53% in 2019. LDL ≤55 mg/dl was 13% in 2015 and 28% in 2019. CONCLUSION: This study shows significant intensification of lipid-lowering therapy use during follow-up, and a significant lipid level lowering after 5-year follow-up, in an outpatient cardiac clinic follow-up. Further improvement in lipid control is still desirable, especially after the European Society of Cardiology recommend stricter lipid levels in the 2021 Prevention Guidelines.

Prognostic Value of Coronary Artery Calcium Score in Hospitalized COVID-19 Patients.

Background: The association of known cardiovascular risk factors with poor prognosis of coronavirus disease 2019 (COVID-19) has been recently emphasized. Coronary artery calcium (CAC) score is considered a risk modifier in the primary prevention of cardiovascular disease. We hypothesized that the absence of CAC might have an additional predictive value for an improved cardiovascular outcome of hospitalized COVID-19 patients. Materials and methods: We prospectively included 310 consecutive hospitalized patients with COVID-19. Thirty patients with history of coronary artery disease were excluded. Chest computed tomography (CT) was performed in all patients. Demographics, medical history, clinical characteristics, laboratory findings, imaging data, in-hospital treatment, and outcomes were retrospectively analyzed. A composite endpoint of major adverse cardiovascular events (MACE) was defined. Results: Two hundred eighty patients (63.2 ± 16.7 years old, 57.5% male) were included in the analysis. 46.7% patients had a CAC score of 0. MACE rate was 21.8% (61 patients). The absence of CAC was inversely associated with MACE (OR 0.209, 95% CI 0.052-0.833, p = 0.027), with a negative predictive value of 84.5%. Conclusion: The absence of CAC had a high negative predictive value for MACE in patients hospitalized with COVID-19, even in the presence of cardiac risk factors. A semi-qualitative assessment of CAC is a simple, reproducible, and non-invasive measure that may be useful to identify COVID-19 patients at a low risk for developing cardiovascular complications.

Troponin T in COVID-19 hospitalized patients: Kinetics matter.

BACKGROUND: Coronavirus disease 2019 (COVID-19) emerged as a worldwide health crisis, overwhelming healthcare systems. Elevated cardiac troponin T (cTn T) at admission was associated with increased in-hospital mortality. However, data addressing the role of cTn T in major adverse cardiovascular events (MACE) in COVID-19 are scarce. Therefore, we assessed the role of baseline cTn T and cTn T kinetics for MACE and in-hospital mortality prediction in COVID-19. METHODS: Three hundred and ten patients were included prospectively. One hundred and eight patients were excluded due to incomplete records. Patients were divided into three groups according to cTn T kinetics: ascending, descending, and constant. The cTn T slope was defined as the ratio of the cTn T change over time. The primary and secondary endpoints were MACE and in-hospital mortality. RESULTS: Two hundred and two patients were included in the analysis (mean age 64.4 ± 16.7 years, 119 [58.9%] males). Mean duration of hospitalization was 14.0 ± 12.3 days. Sixty (29.7%) patients had MACE, and 40 (19.8%) patients died. Baseline cTn T predicted both endpoints (p = 0.047, hazard ratio [HR] 1.805, 95% confidence interval [CI] 1.009-3.231; p = 0.009, HR 2.322, 95% CI 1.234-4.369). Increased cTn T slope predicted mortality (p = 0.041, HR 1.006, 95% CI 1.000-1.011). Constant cTn T was associated with lower MACE and mortality (p = 0.000, HR 3.080, 95% CI 1.914-4.954, p = 0.000, HR 2.851, 95% CI 1.828-4.447). CONCLUSIONS: The present study emphasizes the additional role of cTn T testing in COVID-19 patients for risk stratification and improved diagnostic pathway and management.