BACKGROUND: This study aims 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. The study included cases aged 30 years and older, less than 24 hours post-mortem. 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. Additionally, the measurement data of LAVC components in cases with and without cardiovascular disease (CVD) and their relationships with the demographic characteristics of the cases were 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, along with recommendations for diagnosis and surgical treatment planning. We believe that our findings will be useful to clinicians.