Faculty Bibliography

BACKGROUND:Genetic testing is a cornerstone in the assessment of many cardiac diseases. However, variants are frequently classified as variants of unknown significance, limiting the utility of testing. Recently, the DeepMind group (Google) developed AlphaMissense, a unique artificial intelligence-based model, based on language model principles, for the prediction of missense variant pathogenicity. We aimed to report on the performance of AlphaMissense, accessed by VarCardio, an open web-based variant annotation engine, in a real-world cardiovascular genetics center. METHODS AND RESULTS/RESULTS:<0.001). Genotype-phenotype concordance was highly aligned using VarCard.io predictions, at 95.9% (95% CI, 92.8-97.9) concordance rate. For 109 variants classified as pathogenic, likely pathogenic, benign, or likely benign by ClinVar, concordance with VarCard.io was high (90.5%). CONCLUSIONS:AlphaMissense, accessed via VarCard.io, may be a highly efficient tool for cardiac genetic variant interpretation. The engine's notable performance in assessing variants that are classified as variants of unknown significance in ClinVar demonstrates its potential to enhance cardiac genetic testing.

BACKGROUND:Combined catheter ablation (CA) with percutaneous left atrial appendage closure (LAAC) may produce comprehensive treatment for atrial fibrillation (AF) whereby rhythm control is achieved and stroke risk is reduced without the need for chronic oral anticoagulation. However, the efficacy and safety of this strategy is still controversial. METHODS:This meta-analysis was reported according to the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. Medline, Scopus, and Cochrane Central Register of Controlled Trials were systematically searched to identify relevant studies. The risk of bias was assessed using the Modified Newcastle-Ottawa scale and Cochrane risk of bias tool. Eligible studies reported outcomes in patients with AF who underwent combined CA and LAAC vs CA alone. Studies performing CA without pulmonary vein isolation were excluded. RESULTS:Eight studies comprising 1878 patients were included (2 RCT, 6 observational). When comparing combined CA and LAAC vs CA alone, pooled results showed no difference in arrhythmia recurrence (risk ratio (RR) 1.04; 95% confidence interval (CI) 0.82-1.33), stroke or systemic embolism (RR 0.78; 95% CI 0.27-2.22), or major periprocedural complications (RR 1.28; 95% CI 0.28-5.89). Total procedure time was shorter with CA alone (mean difference 48.45 min; 95% CI 23.06-74.62). CONCLUSION/CONCLUSIONS:Combined CA with LAAC for AF is associated with similar rates of arrhythmia-free survival, stroke, and major periprocedural complications when compared to CA alone. A combined strategy may be as safe and efficacious for patients at moderate to high risk for bleeding events to negate the need for chronic oral anticoagulation.

OBJECTIVES/OBJECTIVE:We investigated characteristics of left atrial conduction in patients with HCM, paroxysmal AF and normal bipolar voltage. BACKGROUND:Patients with hypertrophic cardiomyopathy (HCM) exhibit abnormal cardiac tissue arrangement. The incidence of atrial fibrillation (AF) is increased fourfold in patients with HCM and confers a fourfold increased risk of death. Catheter ablation is less effective in HCM, with twofold increased risk of AF recurrence. The mechanisms of AF perpetuation in HCM are poorly understood. METHODS:We analyzed 20 patients with HCM and 20 controls presenting for radiofrequency ablation of paroxysmal AF normal left atrial voltage(> 0.5 mV). Intracardiac electrograms were extracted from the CARTO mapping system and analyzed using Matlab/Python code interfacing with Core OpenEP software. Conduction velocity maps were calculated using local activation time gradients. RESULTS: = 0.13, p = 0.03). CONCLUSIONS:Atrial conduction velocity is significantly reduced in patients with HCM and paroxysmal AF, possibly contributing to arrhythmia persistence after catheter ablation.

In a letter to the editor titled "How to improve clinical outcomes in patients with tachycardia-induced cardiomyopathy", Dr. Naoya Kataoka and Dr. Teruhiko Imamura [...].

• Precise LAA anatomy must be established for LAA occlusion device selection. • We have developed the TUPLE maneuver, an acronym for “tilt up and turn left”. • The TUPLE maneuver facilitates LAA device selection and intraprocedural guidance.

• LAA membranes are exceedingly rare with variable morphologies. • Thromboembolic risk with LAA membranes remains unknown. • Use of 3D TEE transillumination may assist in visualization and understanding.

• Individual cases of Watchman FLX DAT are scare in literature. • The Watchman FLX has shown lower rates of DAT than the Watchman 2.0. • Thrombus formation is still possible in rare instances with the Watchman FLX.

BACKGROUND:Established electroanatomic mapping techniques for substrate mapping for ventricular tachycardia (VT) ablation includes voltage mapping, isochronal late activation mapping (ILAM), and fractionation mapping. Omnipolar mapping (Abbott Medical, Inc.) is a novel optimized bipolar electrogram creation technique with integrated local conduction velocity annotation. The relative utilities of these mapping techniques are unknown. OBJECTIVE:The purpose of this study was to evaluate the relative utility of various substrate mapping techniques for the identification of critical sites for VT ablation. METHODS:Electroanatomic substrate maps were created and retrospectively analyzed in 27 patients in whom 33 VT critical sites were identified. RESULTS:. CONCLUSION/CONCLUSIONS:ILAM, fractionation, and CV mapping each identified distinct critical sites and provided a smaller area of interest than did voltage mapping alone. The sensitivity of novel mapping modalities improved with greater local point density.

Background: data on the natural course and prognosis of tachycardia-induced cardiomyopathy (TICMP) and comparison with idiopathic dilated cardiomyopathies (IDCM) are scarce. Objective: To compare the clinical presentation, comorbidities, and long-term outcomes of TICMP patients with IDCM patients. Methods: a retrospective cohort study of patients hospitalized with new-onset TICMP or IDCM. The primary endpoint was a composite of death, myocardial infarction, thromboembolic events, assist device, heart transplantation, and ventricular tachycardia or fibrillation (VT/VF). The secondary endpoint was recurrent hospitalization due to heart failure (HF) exacerbation. Results: the cohort was comprised of 64 TICMP and 66 IDCM patients. The primary composite endpoint and all-cause mortality were similar between the groups during a median follow-up of ~6 years (36% versus 29%, p = 0.33 and 22% versus 15%, p = 0.15, respectively). Survival analysis showed no significant difference between TICMP and IDCM groups for the composite endpoint (p = 0.75), all-cause mortality (p = 0.65), and hospitalizations due to heart failure exacerbation. Nonetheless, the incidence of recurrent hospitalization was significantly higher in TICMP patients (incidence rate ratio 1.59; p = 0.009). Conclusions: patients with TICMP have similar long-term outcomes as those with IDCM. However, it portends a higher rate of HF readmissions, mostly due to arrhythmia recurrences.