Catheter ablation procedures for atrial fibrillation (AF) were significantly curtailed during the peak of coronavirus disease 2019 (COVID-19) pandemic to conserve healthcare resources and limit exposure. There is little data regarding peri-procedural outcomes of medical procedures during the COVID-19 pandemic. We enacted protocols to safely reboot AF ablation while limiting healthcare resource utilization. We aimed to evaluate acute and subacute outcomes of protocols instituted for reboot of AF ablation during the COVID-19 pandemic.Perioperative healthcare utilization and acute procedural outcomes were analyzed for consecutive patients undergoing AF ablation under COVID-19 protocols (2020 cohort; n=111) and compared to those of patients who underwent AF ablation during the same time period in 2019 (2019 cohort; n=200). Newly implemented practices included preoperative COVID-19 testing, selective transesophageal echocardiography (TEE), utilization of venous closure, and same-day discharge when clinically appropriate.Pre-ablation COVID-19 testing was positive in 1 of 111 patients. There were 0 cases ablation-related COVID-19 transmission and 0 major complications in either cohort. Pre-procedure TEE was performed in significantly fewer 2020 cohort patients compared to the 2019 cohort patients (68.4% vs. 97.5%, p <0.001, respectively) despite greater prevalence of persistent arrhythmia in the 2020 cohort. Same-day discharge was achieved in 68% of patients in the 2020 cohort, compared to 0% of patients in the 2019 cohort.Our findings demonstrate the feasibility of safe resumption of complex electrophysiology procedures during the COVID-19 pandemic, reducing healthcare utilization and maintaining quality of care. Protocols instituted may be generalizable to other types of procedures and settings.
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.
Abstract Introduction Genetic testing is a cornerstone in the assessment of many cardiac diseases. However, variants are frequently classified as Variants of Unknown Significance (VUS), limiting the utility of testing. Recently, the DeepMind group (Google, USA) developed AlphaMissense, a unique Artificial Intelligence (AI) based model, based on language model principles for the prediction of missense variant pathogenicity. Objective 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 All genetic variants from an inherited arrhythmia program were examined using AlphaMissense via VarCard.io and compared to the ClinVar variant classification system, as well as another variant classification platform (Franklin by Genoox). The mutation reclassification rate and genotype phenotype concordance were examined for all variants in the study. Results We included 266 patients with heritable cardiac diseases, harboring 339 missense variants. Of those, 230 (67.8%) were classified by ClinVar as either VUS or non-classified. Using VarCard.io, 198 VUSs (86.1%, CI 80.9-90.3%) were reclassified to either Likely Pathgenic (LP) or Likely benign (LB). The reclassification rate was significantly higher for VarCard.io than for Franklin (86.1% vs 34.8%, p<0.001). Genotype-Phenotype concordance was highly aligned using VarCard.io predictions, at 95.9% (CI 92.8-97.9%) concordance rate. For 109 variants classified as Pathogenic, LP, Benign or LB by ClinVar, concordance with VarCard.io was high (90.5%). Conclusion 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 VUS in ClinVar, demonstrates its potential to enhance cardiac genetic testing.
Introduction: Patients with hypertrophic cardiomyopathy (HCM) exhibit abnormal cardiac tissue arrangement characterized as myocardial disarray. The incidence of atrial fibrillation (AF) is increased 4-fold in patient with HCM and confers a 4-fold increased risk of death. Catheter ablation is less effective in HCM, with a 2-fold increased risk of AF recurrence. The mechanisms of AF perpetuation and recurrence in HCM are poorly understood. We sought to investigate the left atrial conduction characteristics in patients with HCM, paroxysmal AF and normal left atrial bipolar voltage. Methods: We analyzed 24 consecutive patients with HCM and 24 consecutive controls, all presenting for radiofrequency (RF) ablation of paroxysmal atrial fibrillation. Only patients with normal left atrial voltage (mean voltage >0.8 mV) were included in the study. Intracardiac electrograms were extracted from CARTO (Biosense Webster Inc.) mapping system and analyzed using custom Matlab/Python code interfacing with Core OpenEP software. Conduction velocity was calculated using local activation time gradients. Results: There was no difference in baseline demographic characteristics or atrial size measured by echocardiography between HCM and control patients. Patients with HCM had significantly reduced atrial conduction velocity and conduction velocity dispersion compared to controls (Fig A,C) [0.62±0.03 m/s vs 0.44±0.04 m/s, p=0.002], despite no differences in bipolar voltage (Fig B,D) or voltage dispersion. Patients with HCM had significantly less freedom from AF than controls after catheter ablation [OR for recurrence 3.3 (1.02-10.90), p<0.05 vs control]. Conclusion: Atrial conduction velocity and dispersion is significantly reduced in patients with HCM and paroxysmal AF, possibly contributing to arrhythmia perpetuation and persistence after catheter ablation. This finding may be useful in characterizing left atrial properties beyond bipolar voltage.
Premature ventricular contractions (PVC) in patients without structural heart disease have been associated with focal inflammation at the PVC site of origin (SOO). In the absence of clinical scar on cardiac MRI (CMR) – typically defined as the presence of late gadolinium enhancement (LGE) of at least 5 standard deviations above normal myocardium – the prevalence of focal, lower-intensity LGE in patients with idiopathic PVCs is unknown.
Conducted energy weapon (commonly known as TASER) discharge in patients with implantable cardioverter-defibrillators is known to cause electromagnetic interference and inappropriate ventricular fibrillation sensing without delivery of implantable cardioverter-defibrillators therapy during conducted energy weapon application. We report the first known case of conducted energy weapon discharge resulting in inappropriate implantable cardioverter-defibrillators therapy. (Level of Difficulty: Beginner.)
