Morphometric evaluation of the left atrioventricular valve complex and its clinical relations.

BACKGROUND: In this study, it was aimed to evaluate morphometrically and morphologically the left fibrous ring, mitral leaflets, tendinous cords, and papillary muscles, which are the components of the left atrioventricular valve complex (LAVC), and to reveal their clinical relationships. MATERIALS AND METHODS: A total of 120 human hearts were examined at the Forensic Medicine Institute. Cases aged 30 years and older, less than 24 hours after their death, were included in the study. Heart length, width, height/width ratio, anteroposterior and mediolateral diameters of the annulus, annular area, length and width of leaflets, number and attachment sites of tendinous cords, number, shape, length, the width of papillary muscles, and distances to various points were recorded to determine their spatial configurations. As well as the measurement data of LAVC components in cases with and without cardiovascular disease (CVD), the relationships of these data with the demographic characteristics of the cases are also explained. RESULTS: In the diagnostic performance test (ROC analysis), it was determined that body mass index (> 26.7), heart weight (> 414 g), heart height/width ratio (≤ 1.24), mitral valve width (> 99.96 mm), left ventricular wall thickness (> 15.08 mm), annular area (> 619.37 mm²) and mediolateral diameter of the annulus (> 30.71 mm) are important diagnostic criteria in determining CVD if they are outside the specified reference values. CONCLUSIONS: This study provides anatomical information about LAVC, as well as recommendations for diagnosis and surgical treatment planning. We therefore believe that our findings will be useful to clinicians.

Anatomy of the mitral subvalvular apparatus.

OBJECTIVES: To characterize morphologic variations in the papillary muscles and tendinous cords of the left ventricle and ventricular zones of the mitral valve leaflets. METHODS: A total of 100 autopsied human hearts from healthy donors with classical mitral valve type were investigated. RESULTS: In 1 heart, only 1 group of papillary muscles was found, and in the remaining 99%, we could distinguish 2 groups of muscles: Superolateral (SLPM) and inferoseptal papillary muscle (ISPM) groups. The SLPM group had 1 papillary muscle (75.8%), 2 in 20.2%, and >3 in 4.0%. In the ISPM group, the muscle percentages were 38.4%, 36.4%, and 25.2%, respectively. The apex of at least 1 papillary muscle was situated higher than the plane of the opened anterior leaflet (AML) in 47.5% and 50.5% for the SLPM and ISPM groups, respectively. The number of strut cords arising from the SLPM group was 0 (2.0%), 1 (50.5%), 2 (33.3%), 3 (12.1%), and 4 (2.0%), and from the ISPM group was 0 (6.1%), 1 (52.5%), 2 (35.4%), or 3 (6.1%). Cords to left ventricular outflow tract were present in 14 specimens. Muscular cords were found in eight hearts. In all hearts specimens AML had rough and clear zones. The classical zones (rough, clear, and basal) in the posterior mitral leaflet were observed in 38.4%. CONCLUSIONS: There is a high variability in the papillary muscles and tendinous cords in the mitral valve complex. Proper nomenclature, simple classification, and the most common variants for papillary muscle groups and tendinous cords were presented.

Typification the tendinous cords of the left valve complex of sheep hearts

Forty Santa Ines sheep (Ovis aries Lin.) hearts were examined with the purpose of studying the present types of chordae  tendineae in the left valve complex. The study was performed at the State University of North Fluminense Darcy Ribeiro, Morphology sector of the Agricultural Science Animal Health Center Laboratory. Hearts were initially kept in 10% formalin solution and later dissected to undergo removal and plannifcation of left atrioventricular complex. With the removal of the left atrioventricular complex began the observation and characterization of the cord. After the analysis we observed the presence of eight types of cuspidal chordae tendineae present in the left valve complex, they were classifed as type I, II, III, IV, V, VI, VII and commissural kind.