An Alternative Strategy for Bridge-to-Transplant/Recovery in Small Children with Dilated Cardiomyopathy.

Dilated cardiomyopathy in children still has a poor prognosis with high rates of mortality and cardiac transplantation (resp. around 20 and 25%). Awaiting transplantation or possible recovery, these pediatric patients are mechanically supported with extracorporeal membrane oxygenation or a paracorporeal ventricular assist device, both resulting in higher survival rates but also entailing considerable risks of infection, thrombosis, or bleeding. A new indication for an old technique, i.e., pulmonary artery banding, presents itself as an interesting alternative to mechanical circulatory support in selected infants and small children with dilated LV cardiomyopathy and preserved RV function. Here we present a brief review of literature and report on two patients in whom PAB has been successfully implemented as either bridge-to-recovery or bridge-to-transplant.

Pulmonary artery banding as adjunct therapy for ventricular recovery after anomalous left coronary artery from the pulmonary artery repair: a case report.

Anomalous left coronary artery from the pulmonary artery is a rare congenital coronary anomaly commonly associated with severe but reversible left ventricular dysfunction. We present an anomalous left coronary artery from the pulmonary artery case of persisting left ventricular failure with inability to wean off the ventilator and inotropes after successful coronary reimplantation, in whom pulmonary artery banding enhanced myocardial recovery.

TIM3+ TRBV11-2 T cells and IFNγ signature in patrolling monocytes and CD16+ NK cells delineate MIS-C.

In rare instances, pediatric SARS-CoV-2 infection results in a novel immunodysregulation syndrome termed multisystem inflammatory syndrome in children (MIS-C). We compared MIS-C immunopathology with severe COVID-19 in adults. MIS-C does not result in pneumocyte damage but is associated with vascular endotheliitis and gastrointestinal epithelial injury. In MIS-C, the cytokine release syndrome is characterized by IFNγ and not type I interferon. Persistence of patrolling monocytes differentiates MIS-C from severe COVID-19, which is dominated by HLA-DRlo classical monocytes. IFNγ levels correlate with granzyme B production in CD16+ NK cells and TIM3 expression on CD38+/HLA-DR+ T cells. Single-cell TCR profiling reveals a skewed TCRß repertoire enriched for TRBV11-2 and a superantigenic signature in TIM3+/CD38+/HLA-DR+ T cells. Using NicheNet, we confirm IFNγ as a central cytokine in the communication between TIM3+/CD38+/HLA-DR+ T cells, CD16+ NK cells, and patrolling monocytes. Normalization of IFNγ, loss of TIM3, quiescence of CD16+ NK cells, and contraction of patrolling monocytes upon clinical resolution highlight their potential role in MIS-C immunopathogenesis.

Is there a place for intra-aortic balloon counterpulsation support in acute right ventricular failure by pressure-overload?

BACKGROUND: Most therapeutic strategies for acute right ventricular failure (RVF) by pressure-overload are directed to improve cardiac output and coronary perfusion pressure by vasopressive agents. The eventual role of intra-aortic balloon counterpulsation (IABP) support remains questionable. This study investigates the contribution of IABP for acute RVF by pressure-overload, in comparison with phenylephrine (PE) and norepinephrine (NOR). METHODS: Acute RVF is induced by fixed pulmonary artery constriction in 6 pigs, pursuing a 50% reduction of cardiac output. Assessment of the treatment interventions included biventricular PV-loop analysis, and continuous measurement of aortic and right coronary artery flow. RESULTS: Restoration of baseline cardiac output was only observed by administration of NOR (Baseline=3.82±1.52ml/min - RVF=2.03±0.59ml/min - IABP=2.45±0.62ml/min - PE=2.98±0.63ml/min - NOR=3.95±0.73ml/min, p<0.001). NOR had most effect on biventricular contractility (PRSW-slope-RV: IABP +24% - PE +59% - NOR +208%, p<0.001 and PRSW-slope-LV: IABP +36% - PE +53% - NOR +196%, p<0.001), heart rate acceleration (IABP +7% - PE +12% - NOR +51%, p<0.001), and RCA flow (IABP +31% - PE +58% - NOR +180%, p<0.001), concomitant to a higher increase of LV-to-RV pressure ratio (IABP: +7% versus -3%, PE: +36% versus +8%, NOR: +101% versus 42%). The hemodynamic contribution of IABP was limited, unless a modest improvement of LV compliance during PE and NOR infusion. CONCLUSION: In a model of acute pressure-overload RV failure, IABP appears to offer limited hemodynamic benefit. The administration of norepinephrine is most effective to correct systemic output and myocardial perfusion through adding an inotropic and chronotropic effect to systemic vasopression.