Heterochronia and general pathology illustrated by the example of the human heart.
Heterochronia, heterotopia and heterometria are important elements of the pathogenic process. Heterochronia has its historical roots in the philosophy of Aristotle. As the organs of living creatures and especially man have developed, the process has been one of fitting together a variety of evolutionary bricks. Each complex organ shows evidence of a gradual control of its cellular structure. Parts of organs observed at different stages of man's development all appear to retain certain heterologous (identical) organisational features. Thus, the different pathoclisis is explained. Classical Neuropathology has made headway in this field. Its methodical procedure was adopted - mutatis mutandis - by General Pathology. The inherent structural weaknesses within the organisation of the human brain are, in their organic type of differentiation, also present in the muscular heart. The right ventricle has developed mainly from the myoepicardium of the proampulla; the left ventricle has its origin in the metaampulla. The right ventricle consists mainly of priscomyocardium, the left one of neomyocardium. This is the basis on which are founded the main characteristics of the muscular structures, the arrangement of the coronary arteries and the organisation of the conduction system. A. Keith had already discovered in 1906 that the elements of specific muscle texture contain old structures. We believe that the pacemaker cell represents the historical paradigm of the working muscle cell of the heart (the transporter). Atrioventricular collateral connections (anastomoses) are only found within the priscomyocardium, the arteria coronaria dextra being the original. The coronaria sinistra was evolved later. From the summary of facts originating from the heterochronia of heart development we can draw conclusions about the development of the major heart diseases such as: Those which are dependent on interference with the ventricle walls following oxygen deprivation and the resulting toxic stress; Those which are characterised by infarction of the myocardium which occur in areas which have a predilection for such reaction and which can be set out in a predetermined topology; Those characterised by rhythmic interferences of the heart caused by atrioventricular collateral connections; as a result of an anthropological pathomorphology.
D000885:Anthropology, Physical; D003326:Coronary Circulation; D006321:Heart / Q000196:embryology; D006329:Heart Conduction System; D006330:Heart Defects, Congenital / Q000209:etiology*; D006801:Humans; D009206:Myocardium / Q000473:pathology*; D010684:Philosophy; D010802:Phylogeny