Electromechanical Dyssynchrony Is Associated With Right Ventricular Remodeling and Dysfunction Independently of Pulmonary Regurgitation Late After Tetralogy of Fallot Repair.

BACKGROUND: The aim of this study was to investigate the relationship among right ventricular (RV) dilatation, dysfunction, and electromechanical dyssynchrony (EMD) in patients with repaired tetralogy of Fallot (rTOF). METHODS: Data from a prospective rTOF registry of subjects with moderate or greater pulmonary regurgitation (PR) and contemporary imaging were analyzed. Electrocardiograms and echocardiograms were analyzed for EMD (prolonged QRS duration [QRSd], echocardiographic septal flash, and mechanical delay) and mechanical dispersion. The relationship among these, RV measurements on cardiac magnetic resonance, exercise capacity, and incident arrhythmia or death was analyzed with adjustment for PR. RESULTS: In total, 271 patients with rTOF (42% women; median age, 32 years; interquartile range [IQR], 23-34 years) were included. Patients had moderate to severe PR (median PR fraction, 38%; IQR, 30%-47%), moderate to severe RV enlargement (median RV end-diastolic volume index, 161 mL/m2; IQR, 138-186 mL/m2) and mild RV systolic dysfunction (median RV ejection fraction [RVEF], 44%; IQR, 38%-48%). Eleven patients (4%) experienced ventricular arrhythmia or death. Presence of EMD was associated with larger RV size (RV end-diastolic volume index and RV end-systolic volume index, P = .006 and P < .001, respectively) and lower RVEF (P < .001). A sharp inflection in the relation among QRSd, RV size, and RVEF was observed when QRSd exceeded 150 msec (3.1% decrease in RVEF for every 20-msec increase in QRSd between 160 and 200 msec). Similar inflection points were observed for the mechanical delay between the RV basal-lateral and midseptal segments. The mechanical delay was higher in patients with vs without incident atrial arrhythmia (371 vs 276 msec, P = .014). CONCLUSIONS: In adults with rTOF, EMD is independently associated with larger RV size, lower RVEF, and incident atrial arrhythmias.

Management of COVID-19-associated multisystem inflammatory syndrome in children: A comprehensive literature review.

BACKGROUND: The prevalence and severity of COVID-19 are greatly reduced in children, yet some pediatric patients develop a syndrome resembling Kawasaki Disease (KD), termed Multisystem Inflammatory Syndrome in Children (MIS-C). With an estimated incidence of 2/100,000 children, MIS-C is relatively rare but can be fatal. Clinical features can include fever, hyperinflammatory state, gastrointestinal symptoms, myocardial dysfunction, and shock. The pathogenesis of MIS-C, although yet to be completely elucidated, appears to be distinct from KD in terms of epidemiology, severity, and biochemical signature. AIM OF REVIEW: Although efficacy of treatments for MIS-C have largely not yet been investigated, we aim to conduct a comprehensive literature search of numerous medical databases (AMED, EBM Reviews, Embase, Healthstar, MEDLINE, ERIC, and Cochrane) to highlight treatments used around the world, their rationale, and outcomes to better inform guidelines in the future. Using the findings, an approach to MIS-C management will be outlined. KEY SCIENTIFIC CONCEPTS OF REVIEW: •MIS-C appears to be a SARS-CoV-2 related post-infection phenomenon that is distinct from Kawasaki disease.•Although outcomes are largely favorable, there is significant variation in MIS-C treatment. Most management regimens reported to date mirror that of KD; however, targeted therapy based on specific MIS-C phenotypes may have the potential to improve outcomes.•We recommend close monitoring by a multidisciplinary team, symptomatic treatment (e.g., intravenous immunoglobulin for KD-like symptoms, steroids/immunotherapy for multisystem inflammation), and long-term follow-up.•Further research is required to evaluate the effectiveness of current MIS-C treatments and to determine more refined therapies.