Acute Formation of Thrombus on a Left Atrial Appendage Occlusion Device Immediately After Detachment

Clots can form on the left atrial surface of left atrial appendage closure devices, with subsequent thromboembolization. However, we are unaware of any reports of clots forming on the devices immediately after deployment. We report a case where an acute thrombus strand formed at the tip of an occlusion device immediately after deployment. (Level of Difficulty: Intermediate.

Characterising symptom clusters in patients with atrial fibrillation undergoing catheter ablation

Objective This study aims to leverage natural language processing (NLP) and machine learning clustering analyses to (1) identify co-occurring symptoms of patients undergoing catheter ablation for atrial fibrillation (AF) and (2) describe clinical and sociodemographic correlates of symptom clusters.Methods We conducted a cross-sectional retrospective analysis using electronic health records data. Adults who underwent AF ablation between 2010 and 2020 were included. Demographic, comorbidity and medication information was extracted using structured queries. Ten AF symptoms were extracted from unstructured clinical notes (n=13 416) using a validated NLP pipeline (F-score=0.81). We used the unsupervised machine learning approach known as Ward’s hierarchical agglomerative clustering to characterise and identify subgroups of patients representing different clusters. Fisher’s exact tests were used to investigate subgroup differences based on age, gender, race and heart failure (HF) status.Results A total of 1293 patients were included in our analysis (mean age 65.5 years, 35.2% female, 58% white). The most frequently documented symptoms were dyspnoea (64%), oedema (62%) and palpitations (57%). We identified six symptom clusters: generally symptomatic, dyspnoea and oedema, chest pain, anxiety, fatigue and palpitations, and asymptomatic (reference). The asymptomatic cluster had a significantly higher prevalence of male, white and comorbid HF patients.Conclusions We applied NLP and machine learning to a large dataset to identify symptom clusters, which may signify latent biological underpinnings of symptom experiences and generate implications for clinical care. AF patients’ symptom experiences vary widely. Given prior work showing that AF symptoms predict adverse outcomes, future work should investigate associations between symptom clusters and postablation outcomes

A case of Lactobacillus jensenii associated native valve endocarditis

Lactobacillus jensenii is rarely reported as a cause of endocarditis in immunocompetent patients. We describe a case of Lactobacillus jensenii associated native valve endocarditis that was identified using matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) technology. While most Lactobacillus species are generally resistant to vancomycin, Lactobacillus jensenii is frequently susceptible, but treatment requires accurate susceptibility results followed by timely medical and surgical intervention. Probiotic use in patients can be a risk factor for infection with Lactobacillus species