In order to establish the relationship between the timing of fetal obliteration of communication and expression remodeling of the heart chambers, as one of the possible causative factors of SIDS, the selected material has been based on macromorphometric study. Material included 43 hearts from infants who died of SIDS. The control group consisted of 48 hearts of children suddenly dead from aspiration of gastric contents and infectious disease. The methods composed a macroscopic examination of the heart by the method of separate weighing of the complex morphometric studies, histological examination (used the following stains: hematoxylin and eosin, picrofuchsin by Van Gieson, Nissl's stain), immunohistochemical method using markers of neurofilament. The results revealed that in children who died of SIDS, obliteration of the fetal communication occurs essentially in the late period —to the age of 8 months, and the mass of the left and right ventricles of the heart exceeds the age limit of normal due to the prevalence of ventricular muscle mass and hypertrophy of cardiomyocytes. In all parts of the heart subendocardial fibrosis in the ventricles — pronounced interstitial fibrosis has been observed. In the interatrial septum at the location at the oval window morphometric study resulted in significant predominance area percentage of connective tissue in relation to the muscle tissue. On histological sections elements of the nervous tissue — randomly arranged nerve ganglia with degenerative changes and nerve fibers were identified. Conclusion. Finally, it should be noted that the growth of cardiosclerosis in all parts of the heart in newborns and infants, who died suddenly from SIDS, extends the terms of obliteration of fetal communications, and degenerative changes in the nerve ganglia that lead to the disturbance of supply and distribution of nerve impulses that pass through them. These factors contribute to the development of hemodynamic disturbances and may be important in the development of sudden death in children.
Rozumny D.V. Pathomorphological cardial changes in the sudden infant death syndrome // Saratov Journal of Medical Scientific Research, Vol. 10, Issue 1, 2014, pp. 48-52

One hundred twenty-three babies died at home at the age of 1–12 months have been examined from 2004 till 2008. 39 babies died from sudden infant death syndrome (SIDS). The comparison group has been composed of 58 babies of the same age died at home from various diseases. Investigations have been performed in DGCB N1, Samara. About 95 % of babies died from SIDS at home during the first six months of their life, with top mortality between 1 till 3 months. There was sexual difference — 67 % of boys. The majority of home death cases have happened in summer — 49 babies (30%). Morphological investigations have been made including different heart weighting, histological and histometric examination of cardiomyocites. It has been revealed that in the group of babies died from SIDS the most constant symptoms have included: right heart hypertrophy, great heart weight variability, ventricular index.
Yu. R. Yunusova Pathological Anatomy and Quantitative Analysis of morphologic dimensions of 1-Year Old Children Hearts in Case of Sudden Death at Home // Saratov Journal of Medical Scientific Research, Vol. 5, Issue 2, 2009, pp. 148-150