Cardiac comorbidities in patients with erythromelalgia: A retrospective database analysis

Summary: Abstract Body: Primary erythromelalgia is a rare condition characterized by numerous dermatologic findings and caused by mutation in the SCN9A gene which encodes the Nav1.7 voltage-gated sodium channel. Given the presence of the Nav1.7 channel in the cardiac system, the potential for alterations in microcirculation in affected areas, and the known association of PAD with adverse cardiac events, our studies aims to assess the relationship between EM and comorbid cardiac conditions. Our study used the All of Us Database (AoUDB) from the National Institute of Health to assess the increased risk for cardiac comorbidities in patients with EM. The AoUDB database returned 88 patients with EM out of the 287,012 patients in the database with EHR data. Cardiac comorbidities queried fell into three categories: conduction abnormalities (heart block and bundle branch block), myocardial infarctions, and angina. Patients with erythromelalgia had significantly higher odds of angina pectoris (OR=2.12; p=0.021), ST-segment elevation myocardial infarction (OR=3.48; p=0.038), and left bundle branch block (OR=2.57; p=0.048). The cohort of EM patients in the AoUDB exhibited significantly higher rates of multiple cardiac events including those with underlying conduction etiologies consistent with current literature supporting that modification of Nav1.7 activity may precipitate changes to autonomic systems. These increased rates underscore the significance of EM as not only an indicator of underlying neuropathy but also potential underlying cardiac abnormalities. The primary limitation of this study is the lack of granularity between primary and secondary EM, potentially dampening the magnitude of the relationship. Nevertheless, our results reached statistical significance for multiple adverse cardiac outcomes in patients with EM. Christopher Guirguis¹, Ryan Braun¹, Lauren Ching¹, Mikael Horissian² 1. Georgetown University School of Medicine, Washington, DC, United States. 2. Dermatology, Geisinger Health, Danville, PA, United States. Clinical Research: Epidemiology and Observational Research