Myocardial Infarction in Children after COVID-19 and Risk Factors for Thrombosis

One-Year Follow-Up Results of MIS-C Patients with Coronary Artery Involvement: A Multi-center Study

Multisystem inflammatory syndrome (MIS-C) in children is a rare complication of SARS-CoV-2 infection. Knowing the course of the affected or unaffected coronary arteries in the patients under follow-up is important in terms of defining the long-term prognosis of the disease and determining the follow-up plan. This is a multicenter and retrospective study. The data were obtained from nine different centers. Between May 2020 and August 2022, 68 of 790 patients had coronary artery involvement. One-year echocardiographic data of 67 of 789 MIS-C patients with coronary artery involvement were analyzed. Existing pathologies of the coronary arteries were grouped as increased echogenicity, dilatation and aneurysm according to Z scores, and their changes over a 1-year period were determined. The data of all three groups are defined as frequency. SPSS Statistics version 22 was used to evaluate the data. In our study, aneurysm was observed in 16.4%, dilatation in 68.7% and increased echogenicity in 13.4% of the patients. All of the patients with involvement in the form of increased echogenicity recovered without sequelae by the end of the first month. No progression to aneurysm was observed in any of the patients with dilatation. No new-onset involvement was observed in patients with previously healthy coronary arteries during the convalescent period. In addition, from the sixth month follow-up period, there was no worsening in the amount of dilatation in any of the patients. At least 94% of the patients who completed the 12th month control period returned to normal.

Giant Coronary Aneurysms with Multiple Large Resistant Thromboses in an 8-Month-Old Boy with IVIg-Resistant Kawasaki Disease: A Case Report

Kawasaki disease is an acute self-limiting systemic vasculitis in childhood, resulting in arterial swelling or inflammation and eventually leading to cardiovascular problems, such as coronary artery aneurysms. Based on previous studies, serum sodium ≤133 mmol/L, albumin ≤3.2 g/dL, alanine transaminase ≥80 U/L, and neutrophil percentage ≥80% at diagnosis are risk factors for intravenous immunoglobulin (IVIg). However, the prevalence of resistance to Ig among children with Kawasaki disease varies among different countries due to diversity in evaluation, treatment, and diagnosis. Approximately, 10% to 20% of patients have IVIg-resistant Kawasaki disease. As the probability of coronary artery damage associated with IVIg-resistant Kawasaki disease is higher than that with IVIg-sensitive Kawasaki disease, the early detection and appropriate treatment of IVIg-resistant Kawasaki disease can decrease the probability of damage to coronary arteries and hospital lengths of stay and cost. Kawasaki disease in early infancy is uncommon, and sometimes it occurs with thrombosis and peripheral gangrene. A positive genetic background may play a role in susceptibility to thrombosis. We herein describe a patient suffering from an IVIg-resistant Kawasaki disease with severe coronary artery thrombosis and positive genetic mutation. Medical treatment resolved the thrombosis, but the coronary arteries remained dilated.

Thrombotic Events in MIS-C Patients: A Single Case Report and Literature Review

Multisystem Inflammatory Syndrome in Children (MIS-C) is a systemic hyperinflammatory disorder that is associated with a hypercoagulable state and a higher risk of thrombotic events (TEs). We report the case of a 9-year-old MIS-C patient with a severe course who developed a massive pulmonary embolism that was successfully treated with heparin. A literature review of previous TEs in MIS-C patients was conducted (60 MIS-C cases from 37 studies). At least one risk factor for thrombosis was observed in 91.7% of patients. The most frequently observed risk factors were pediatric intensive care unit hospitalization (61.7%), central venous catheter (36.7%), age >12 years (36.7%), left ventricular ejection fraction <35% (28.3%), D-dimer >5 times the upper limit of normal values (71.9%), mechanical ventilation (23.3%), obesity (23.3%), and extracorporeal membrane oxygenation (15%). TEs may concurrently affect multiple vessels, including both arterial and venous. Arterial thrombosis was more frequent, mainly affecting the cerebral and pulmonary vascular systems. Despite antithrombotic prophylaxis, 40% of MIS-C patients developed TEs. Over one-third of patients presented persistent focal neurological signs, and ten patients died, half of whom died because of TEs. TEs are severe and life-threatening complications of MIS-C. In case with thrombosis risk factors, appropriate thromboprophylaxis should be promptly administered. Despite proper prophylactic therapy, TEs may occur, leading in some cases to permanent disability or death.

Should We Be Screening for Ischaemic Heart Disease Earlier in Childhood?

Ischaemic heart disease is the most common cause of death in males and the second in the female gender. Yet we often only focus on identification and treatment of this foremost cause of death in adulthood. The review asks the question what form of coronary disease do we encounter in childhood, what predisposing factors give rise to atherosclerosis and what strategies in childhood could we employ to detect and reduce atherosclerosis development in later life.