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A comparison of the data published in anatomy textbooks and anthropological tables does not reveal any change in basic heart dimensions during the period since the beginning of the 20th century to nowadays. However, normal values of many other parameters have changed up to 30% over the same period. These changes may be caused by the acceleration phenomenon or the extension of average lifespan. The progress of laboratory medicine methodology permitted the introduction of new biochemical tests in myocardial infarct diagnosis, such as myoglobin and troponins T and I measurement, as well as better understanding of cardiac metabolism. Parameters describing the direction and intensity of metabolic changes are substrate extraction and metabolic equilibrium. The expression describing metabolic equilibrium contains heart mass value. Therefore, as studying heart mass in vivo is not possible, it may be important to study it in vitro. The study was performed on a group of 107 formalin-fixed human hearts. The organs came from adults of both sexes: 30 women and 77 men, aged 18 to 90 years. None of the hearts carried signs of macroscopic developmental abnormalities or pathologic changes.
In addition to the papillary muscles of right ventricle referred to in anatomical nomenclature, namely the anterior, posterior and septal, we have distinguished the “conal papillary muscle” and the “papillary muscle of the posterior angle of the right ventricle”. The conal papillary muscle was described by Luschka in the 17th century as the most constant of the septal papillary muscles. We have distinguished the muscles of the posterior angle of the right ventricle as muscles which would not be clearly classified as either septal or posterior muscles. Moreover, the muscles of the posterior angle of the right ventricle are probably associated with the transfer of the papillary muscles from the septum to the posterior wall of the right ventricle during phylogenetic evolution. Some researchers have classified them with the septal papillary muscles [11, 12], while others have assigned them to the posterior group [5]. The morphology of the muscles was classified using earlier categories for the posterior papillary muscles only. We have adopted the concept of multi-apical and multi-segmental muscles [5].
Despite the great interest taken in the tricuspid valve, the anatomical literature on the subject still leaves much open to question. The aim of this study was to describe the natural foramina which are present in the leaflets of the tricuspid valve, as well as, well — founded onto — and phylogenetically lack of continuity of its attachment and the frenula of the tricuspid valve. We studied the frequency of occurrence and morphology of these features of the tricuspid valve in 107 adult hearts.
Studies of the morphometry and normal anatomy of the tricuspid valve are in constant demand. Knowledge of the morphology of the normal tricuspid valve may be useful, for example in the context of the transfer of a leaflet of the tricuspid valve for repair or insufficiency of the mitral valve, in repair of the tricuspid valve after blunt chest trauma and in other surgical techniques of this region. In this study, performed in a group of 107 formalin-fixed adult human hearts, we attempted to assess the form and number of the main and accessory cusps in the tricuspid valve. Rare anatomical variants of the tricuspid valve were found. Using a planimeter we evaluated the surface area of the tricuspid valve and particular leaflets. With the help of a Vernier scale we measured the length and height of individual leaflets of the tricuspid valve and the length of the commissures. No differences were found between the length of the anterior and septal leaflets. The posterior leaflet was the shortest, while the anterior leaflet was the widest and had the largest surface area. The posterior leaflet was wider than the septal leaflet and had the smallest surface area. No differences were found between the main and accessory leaflets in the length of the commissures.
The tricuspid valve is more differentiated during evolutionary development than the mitral valve. In birds it is a muscular structure joined directly to the papillary muscles, although the mitral valve of birds resembles that of mammals. There have been well-known studies describing the evolutionary line of connection of the tricuspid valve with the papillary muscles. The present study was performed on a group of 107 formalin-fixed adult human hearts. The valves and papillary muscles were classified according to a scheme for human hearts drawn up earlier. The types of connection between leaflets of the tricuspid valve and the papillary muscles were classified according to a scheme drawn up earlier for vertebrates. We observed 3 types of connection between leaflets of the tricuspid valve and the papillary muscles in the group studied. The muscular and membranous connections were not linked with any one type of tricuspid valve. Atypical forms of distribution of the tendinous chords of the right ventricle were observed. It was found that valves with a higher number of leaflets were (with the exception of type 0) provided with a smaller number of tendinous chords. Atavistic features and atypical forms of distribution of the tendinous chords are present in a small percentage of samples of the human right valvular apparatus.
Rapid progress in the field of interventional cardiology has caused research in the field of morphometry of the heart to be in constant demand [7–10, 12]. In this study, performed on a group of 75 adult human hearts, the authors have attempted to assess the form and number of the main and accessory cusps in the tricuspid valve. We have classified particular forms into 8 groups, depending on the number of cusps and we have divided the cusps into 3 main groups, depending on the support of the chordae tendineae.
Muscle bridges (MBs) are structures consisting of heart muscle tissue which pass above the coronary arteries and their branches. Although there are a relatively large number of descriptions of these MBs, researchers do not share a common view of the frequency of their occurrence, their location and their morphology, which remain the most controversial questions. The present research was carried out on 300 human hearts, adults of both sexes (161 male and 139 female), of between 21 and 76 years of age (mean age 48 years), in which no macroscopic developmental failures had been found. The hearts were preserved in formalinethanol solution. Selected coronary arteries were analysed. Images were examined of the perpendicular dissection of the coronary arteries and their neighbouring structures. On the basis of the analysis, the frequency of occurrence of MBs was defined as 31.3%. Muscular bridges were observed most frequently over the anterior interventricular branch of the left coronary artery (RIA) and, more rarely, over the right marginal branch of the left coronary artery (Rmd) and the circumflex branch of the left coronary artery (RCX). Using as criteria the number of muscular bridges in the heart and their location over particular coronary arteries, 4 types of configuration were established. With reference to the RIA, most MBs were located in the central part. We did not notice the same regularity with reference to other coronary arteries, nor did we observe MBs over coronary veins. Conclusions: muscular bridges are frequently observed structures in human hearts, most often seen over the anterior interventricular branch of the left coronary artery (RIA), mainly over its central segments, and occasionally over other arteries. MBs may occur in the heart singly or in a greater number and are found over the same or different vessels.
Congenital abnormalities of the aortic arch arise due to a defect in the unilateral disappearance of arteries of the IVth and exceptionally of the IIIrd primary branchial arches and also of the appropriate sections of paired dorsal aortas. Apart from the cases of complete “situs inversus” and a double aortic arch, the following anatomical possibilities can be distinguished: A — a left-sided aortic arch with a properly established system of branches, B — a left-sided aortic arch with an aberrant right subclavian artery, C — a left-sided aortic arch with a retroesophageal course and right-sided descending aorta or retro-esophageal course of the brachiocephalic trunk onto the right side, D — a right-sided aortic arch of the „symmetric” type usually coexisting with cyanotic congenital heart lesions, E — a right-sided aortic arch with a retro-esophageal bulge and an aberrant left subclavian artery, and F — a right-sided aortic arch with an aorta descending left-sidedly or brachiocephalic trunk going left-sidedly behind the esophagus. At the Department of Anatomy from 1945 to 1998, 1700 adult cadavers were examined. Throughout this time, one case of each of the types E and C and two cases of the type B were noted in the material. Regardless of the rare occurrence among adults (about 0.01%), the abnormal course of the aortic arch can be the reason for atypical clinical symptoms such as esophageal compression and dysphagia or insufficient cerebral blood supply.
The term annulus fibrous is still used in anatomical and clinical terminology but does not exist in anatomical nomenclature. This structure is proposed as an anatomical substrate for circus movement of excitation. Multiple cardiac damage after blunt chest trauma is rare, but usually affects the septal part of the right fibrous annulus. Histological observation confirms the results of our previous macroscopic study and shows that the most stable part of fibrous annulus is the septal part and the region of anterior angle of the right ventricle, and the most labile parts are the lateral and posterior angles of the right ventricle and the posterior part of the fibrous annulus. Our histological study shows that the right fibrous annulus is a heterogeneous structure and may play a role in changes of shape of the right atrio-ventricular ostium during human life. (Folia Morphol 2009; 68, 1: 32–35)
Cardiac arrhythmias have troubled patients and fascinated physicians for centuries. The twentieth century was an era of progress, when the mechanism of cardiac disorders became more commonly recognised. Arrhythmias may be due to abnormalities of automaticity, to abnormalities of conduction, or to a combination of both. In order for re-entry to occur, an area of slowing conduction combined with unidirectional block must be present. Much investigation has centred on the underlying re-entry mechanisms of atrial flutter. In the light of these facts, it would seem that a close acquaintance with the detailed topography of the vena cava orifice (cavo), coronary sinus orifice (sinus) and the attachment of the septal leaflet of the tricuspid valve (tricupid) area could be of great interest, especially for invasive cardiologists. The research was conducted on material consisting of 41 hearts of humans of both sexes from the age of 12 to 80 (6 female, 35 male). Classical macroscopic methods of anatomical evaluation were used. The following measurements were made: the shortest distance between the Eustachian valve and the attachment of the tricuspid valve on the left margin of the coronary sinus orifice (diameter 1), the distance between the attachment of the tricuspid valve and the inferior margin of the sinus orifice (diameter 2), the distance between the Eustachian valve and the attachment of the tricuspid valve on the right margin of the coronary sinus orifice (diameter 3), the distance between the inferior margin of the vena cava inferior and the attachment of the tricuspid valve (diameter 4) and, finally, the diameter between the attachment of the septal cups of the tricuspid valve and the external border of the vena cava inferior (diameter 5). No correlation was found between the age and sex of the three groups of the material. The dimensions of the structure examined were similar in the three groups of hearts. In young adult hearts all the diameters measured ranged from 4 to 47 mm The average diameters were, respectively: 15.02 mm (diameter 1), 8.97 mm (diameter 2), 17.27 mm (diameter 3), 26.87 mm (diameter 4), 36.42 mm (diameter 5). In the mature adult hearts all the diameters measured ranged from 8 to 45 mm: 18.19 mm (diameter 1), 10.54 mm (diameter 2), 19.95 mm (diameter 3), 28.90 mm (diameter 4), 39.63 mm (diameter 5). In the older adults hearts all the diameters measured ranged from 4 to 47 mm. The average diameters were, respectively: 15.65 mm (diameter 1), 8.70 mm (diameter 2), 7.25 mm (diameter 3), 26.80 mm (diameter 4), 35.85 mm (diameter 5).
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