Saito Kazuyoshi

Reports regarding coronavirus disease 2019 (COVID-19) with Fontan circulation are limited. Most studies indicate a relatively good clinical outcome in which SARS-CoV-2 infection is abated; however, COVID-19 can still cause severe pneumonia, and some studies report circulatory breakdown associated with acute respiratory distress syndrome in patients with Fontan circulation. We present the case of a 32-year-old Japanese woman with right isomerism and a single right ventricle who had undergone a fenestrated extracardiac total cavopulmonary connection (Fontan operation), atrioventricular valve replacement, and pacemaker implantation. Despite receiving three doses of the severe acute respiratory syndrome coronavirus 2 mRNA vaccine, the patient contracted COVID-19 and presented with pneumonia. Although her symptoms were mild, the patient was classified as high-risk based on the European Society of Cardiology risk stratification guidelines for COVID-19 in patients with adult congenital heart disease and was admitted to the hospital. Initially, the patient received only symptomatic treatment. However, 2 days later, the patient's COVID-19 condition worsened to moderate grade level II (SpO2 ≤93%, oxygen demand), with SpO2 dropping from 95% to 88% on room air. Treatment with remdesivir and dexamethasone following Japanese treatment protocols resulted in clinical improvement and discharge without hemodynamic complications. COVID-19 pneumonia risks disrupting Fontan circulation in affected patients. This case illustrates the importance of prompt risk stratification using anatomical and physical evaluation and adherence to treatment guidelines in the management of patients with Fontan circulation and COVID-19.

UNLABELLED: As an alternative to implantable cardioverter defibrillators, the wearable cardioverter defibrillator (WCD; LifeVest®, Asahi KASEI Zoll Medical Co., Tokyo, Japan) is the only noninvasive cardioverter defibrillator available that can be worn directly on the skin. The first consensus statement on WCD use in Japan was published in 2014, and, similar to guidelines in other countries, its recommendations focus on adult patients. Pediatric cases involving WCD remain limited, and appropriate indications for its use in children are yet to be established. Here, we report the first pediatric case in Japan where WCD monitored a patient and delivered an appropriate shock to terminate a life-threatening ventricular tachycardia and ventricular fibrillation episode. During this time, the patient was recovering from takotsubo cardiomyopathy, presumably associated with refeeding syndrome secondary to Crohn's disease. No inappropriate shocks were delivered during the three-month monitoring period, and the WCD use was deemed safe. The continuous monitoring function of WCD aided in understanding the patient's conditions. Following treatment, the patient has recovered from Crohn's disease and his cardiac function has stabilized, and he has not experienced neurological sequelae or heart failure symptoms since. This case highlights the potential of WCD use in pediatric patients. LEARNING OBJECTIVE: The wearable cardioverter defibrillator (WCD; LifeVest®) is the only noninvasive cardioverter defibrillator available. However, current guidelines around the world primarily focus on adult patients. Cases of pediatric patients who are rescued by an appropriate shock by WCD are still limited and many aspects, such as device set-up, effectiveness, and risks require further study. This case supports that WCD in children can be safe and effective, demonstrating its potential to protect against ventricular tachycardia and ventricular fibrillation and prevent sudden cardiac death.