RESUMO
Cardiac stimulation via sympathetic neurons can potentially trigger arrhythmias. We present approaches to study neuron-cardiomyocyte interactions involving optogenetic selective probing and all-optical electrophysiology to measure activity in an automated fashion. Here we demonstrate the utility of optical interrogation of sympathetic neurons and their effects on macroscopic cardiomyocyte network dynamics to address research targets such as the effects of adrenergic stimulation via the release of neurotransmitters, the effect of neuronal numbers on cardiac behavior, and the applicability of optogenetics in mechanistic in vitro studies. As arrhythmias are emergent behaviors that involve the coordinated activity of millions of cells, we image at macroscopic scales to capture complex dynamics. We show that neurons can both decrease and increase wave stability and re-entrant activity in culture depending on their induced activity-a finding that may help us understand the often conflicting results seen in experimental and clinical studies.
RESUMO
Neonatal Marfan syndrome (nMFS) is a rare condition with a poor prognosis. It is genotypically and phenotypically distinct from the typical Marfan syndrome and carries a poorer prognosis. This case report describes the progression of a 14-month-old girl diagnosed with nMFS at 5 months of age. Her diagnosis followed the identification of a fibrillin-1 mutation (FBN1 gene, exon 26, chromosome 15), which is a common locus of nMFS. This patient developed severe cardiac complications resulting in congestive cardiac failure in early life and required major cardiac surgery. Since surgical intervention, our patient is still reliant on a degree of ventilator support, but the patient has gained weight and echocardiography has demonstrated improved left ventricular function and improved tricuspid and mitral valve regurgitation. Therefore, we argue the importance of a cautious multidisciplinary approach to early surgical intervention in cases of nMFS.