Abstract:
In the transposition of the great arteries (TGA), alterations in hemodynamics and oxygen saturation could result in fibrotic remodeling, but histological studies are scarce. We aimed to investigate fibrosis and innervation state in the full spectrum of TGA and correlate findings to clinical literature. Twenty-two human postmortem TGA hearts, including TGA without surgical correction (n = 8), after Mustard/Senning (n = 6), and arterial switch operation (ASO, n = 8), were studied. In newborn uncorrected TGA specimens (1 day-1.5 months), significantly more interstitial fibrosis (8.6% ± 3.0) was observed compared to control hearts (5.4% ± 0.8, p = 0.016). After the Mustard/Senning procedure, the amount of interstitial fibrosis was significantly higher (19.8% ± 5.1, p = 0.002), remarkably more in the subpulmonary left ventricle (LV) than in the systemic right ventricle (RV). In TGA-ASO, an increased amount of fibrosis was found in one adult specimen. The amount of innervation was diminished from 3 days after ASO (0.034% ± 0.017) compared to uncorrected TGA (0.082% ± 0.026, p = 0.036). In conclusion, in these selected postmortem TGA specimens, diffuse interstitial fibrosis was already present in newborn hearts, suggesting that altered oxygen saturations may already impact myocardial structure in the fetal phase. TGA-Mustard/Senning specimens showed diffuse myocardial fibrosis in the systemic RV and, remarkably, in the LV. Post-ASO, decreased uptake of nerve staining was observed, implicating (partial) myocardial denervation after ASO.
摘要:
在大动脉转位(TGA)中,血流动力学和氧饱和度的改变可能导致纤维化重塑,但是组织学研究很少。我们旨在研究TGA全谱的纤维化和神经支配状态,并将发现与临床文献相关联。22个人类死后的TGA心脏,包括没有手术矫正的TGA(n=8),芥末/森宁(n=6)之后,和动脉开关操作(ASO,n=8),被研究过。在新生儿未矫正TGA标本(1天-1.5个月),与对照组心脏(5.4%±0.8,p=0.016)相比,观察到显著更多的间质纤维化(8.6%±3.0).芥末/森宁程序后,间质纤维化的数量显著增加(19.8%±5.1,p=0.002),肺下左心室(LV)明显高于全身右心室(RV)。在TGA-ASO,在一个成人标本中发现纤维化量增加。与未校正的TGA(0.082%±0.026,p=0.036)相比,神经支配的量从ASO后3天减少(0.034%±0.017)。总之,在这些选定的死后TGA标本中,弥漫性间质纤维化已经存在于新生心脏中,提示氧饱和度的改变可能已经影响胎儿期的心肌结构。TGA-Mustard/Senning标本显示全身性RV和弥漫性心肌纤维化,值得注意的是,在LV。ASO后,观察到神经染色的摄取减少,ASO后涉及(部分)心肌神经支配。