Age-related changes in aortic and mitral valve thickness: Implications for two-dimensional echocardiography based on an autopsy study of 200 normal human hearts

doi:10.1016/0002-9149(88)90971-X

The American Journal of Cardiology

Volume 62, Issue 7, 1 September 1988, Pages 424-430

https://doi.org/10.1016/0002-9149(88)90971-X Get rights and content

Abstract

The thicknesses at 3 sites of each aortic cusp (nodule, closing edge and middle part) and 2 sites of both mitral leaflets (closing edge and clear zone) were measured in 200 autopsy specimens of normal hearts, evenly distributed by age and sex. There were no significant correlations between valvular thickness and height, weight, heart weight or body surface area. The mean thickness at each site was not different between men and women but increased significantly with age (p < 0.001). For 3 age groups (< 20, 20 to 59 and ≥ 60 years), the corresponding mean thicknesses (mm) of the aortic nodule were 0.67, 0.87 and 1.42; those for the anterior mitral leaflet were 1.30, 1.60 and 3.20; and those for the posterior mitral leaflet were 0.91, 1.13 and 2.04. For the aortic valve, the nodule was nearly twice as thick as the closing edge (p < 0.001), and the closing edge was at least 25% thicker than the middle part (p < 0.001). Furthermore, the posterior aortic cusp was thicker than the right and left cusps (p < 0.05). For both mitral leaflets, the closing edge was thicker than the clear zone (p < 0.05). Moreover, along the closing edges, the anterior leaflet was thicker than the posterior leaflet (p < 0.05). These observations may be useful in echocardiographic evaluations of aortic and mitral valve sclerosis in elderly patients.

References (31)

S Westaby et al.
Adult human valve dimensions and their surgical significance
Am J Cardiol
(1984)
I Schnittger et al.
Standardized intracardiac measurements of two-dimensional echocardiography
JACC
(1983)
FEMG Vollebergh et al.
Minor congenital variations of cusp size in tricuspid aortic valves: possible link with isolated aortic stenosis
Br Heart J
(1977)
PT Hagen et al.
Incidence and size of patent foramen ovale during the first 10 decades of life: an autopsy study of 965 normal hearts
DG Scholz et al.
Age-related changes in normal human hearts during the first 10 decades of life. Part I (growth): a quantitative anatomic study of 200 specimens from subjects from birth to 19 years old
DW Kitzman et al.
Age-related changes in normal human hearts during the first 10 decades of life. Part II (maturity): a quantitative anatomic study of 765 specimens from subjects 20 to 99 years old
WD Edwards
Anatomic basis for tomographic analysis of the heart at autopsy
Cardiol Clin
(1984)
J Neter et al.
Applied Linear Statistical Models
S Sell et al.
Aging changes in the aortic and mitral valves: histologic and histochemical studies, with observations on the pathogenesis of calcific aortic stenosis and calcification of the mitral annulus
Am J Pathol
(1965)
ML Johnson et al.
Ultrasonic evaluation of prosthetic valve motion
Circulation
(1970)

MJ Davies

Pathology of Cardiac Valves

JM Gardin et al.

Echocardiographic measurements in normal subjects: evaluation of an adult population without clinically apparent heart disease

J Clin Ultrasound

(1979)

WL Henry et al.

Echocardiographic measurements in normal subjects: growth-related changes that occur between infancy and early adulthood

Circulation

(1978)

WA McAlpineWA McAlpine

GM Hutchins et al.

Measurements of cardiac size, chamber volumes and valve orifices at autopsy

Johns Hopkins Med J

(1973)

Cited by (135)

Simulation-based design of bicuspidization of the aortic valve
2024, Journal of Thoracic and Cardiovascular Surgery
Severe congenital aortic valve pathology in the growing patient remains a challenging clinical scenario. Bicuspidization of the diseased aortic valve has proven to be a promising repair technique with acceptable durability. However, most understanding of the procedure is empirical and retrospective. This work seeks to design the optimal gross morphology associated with surgical bicuspidization with simulations based on the hypothesis that modifications to the free edge length cause or relieve stenosis.
Model bicuspid valves were constructed with varying free edge lengths and gross morphology. Fluid-structure interaction simulations were conducted in a single patient-specific model geometry. The models were evaluated for primary targets of stenosis and regurgitation. Secondary targets were assessed and included qualitative hemodynamics, geometric height, effective height, orifice area, and billow.
Stenosis decreased with increasing free edge length and was pronounced with free edge length less than or equal to 1.3 times the annular diameter d. With free edge length 1.5d or greater, no stenosis occurred. All models were free of regurgitation. Substantial billow occurred with free edge length 1.7d or greater.
Free edge length 1.5d or greater was required to avoid aortic stenosis in simulations. Cases with free edge length 1.7d or greater showed excessive billow and other changes in gross morphology. Cases with free edge length 1.5d to 1.6d have a total free edge length approximately equal to the annular circumference and appeared optimal. These effects should be studied in vitro and in animal studies.
An FSEI approach for the assessment of stenotic aortic valve effects on the left heart hemodynamics
2023, Computers and Fluids
Fluid–structure-electrophysiology interaction (FSEI) deals with (i) the active contraction of the myocardium, (ii) the complex blood motion and (iii) the related deformation of the cardiac tissues. This three-way coupled approach is key for obtaining predictive cardiac information as the tissue kinematics comes as a part of the solution, rather than being imposed as a boundary condition. FSEI is here applied to study the effects induced by aortic valve stenosis on the hemodynamics. This pathology, typically occurring in elderly individuals, is caused by the stiffening of the valve leaflets, thus impairing the valve functioning and reducing the pumping efficiency of the heart. The disease severity is gradually increased within a high-fidelity model for the left heart, while keeping the same geometrical, elastic and electrophysiological properties of the cardiac system, which would be impossible with in-vivo experiments. We observe an increase of the transvalvular pressure drop and of the peak velocity of the systolic jet velocity along with a reduction of the cardiac ejection fraction. Furthermore, a stenotic aortic valve significantly alters the wall shear stresses and their spatial distribution over the aortic arch and valve leaflets, which may induce a remodeling process of the ventricular myocardium. The numerical results from the multi-physics model are fully consistent with the clinical experience, thus further opening the way for computational engineering aided medical diagnostic.
Recommendations for the Use of Echocardiography in the Evaluation of Rheumatic Heart Disease: A Report from the American Society of Echocardiography
2023, Journal of the American Society of Echocardiography
Acute rheumatic fever and its chronic sequela, rheumatic heart disease (RHD), pose major health problems globally, and remain the most common cardiovascular disease in children and young people worldwide. Echocardiography is the most important diagnostic tool in recognizing this preventable and treatable disease and plays an invaluable role in detecting the presence of subclinical disease needing prompt therapy or follow-up assessment. This document provides recommendations for the comprehensive use of echocardiography in the diagnosis and therapeutic intervention of RHD. Echocardiographic diagnosis of RHD is made when typical findings of valvular and subvalvular abnormalities are seen, including commissural fusion, leaflet thickening, and restricted leaflet mobility, with varying degrees of calcification. The mitral valve is predominantly affected, most often leading to mitral stenosis. Mixed valve disease and associated cardiopulmonary pathology are common. The severity of valvular lesions and hemodynamic effects on the cardiac chambers and pulmonary artery pressures should be rigorously examined. It is essential to take advantage of all available modalities of echocardiography to obtain accurate anatomic and hemodynamic details of the affected valve lesion(s) for diagnostic and strategic pre-treatment planning. Intraprocedural echocardiographic guidance is critical during catheter-based or surgical treatment of RHD, as is echocardiographic surveillance for post-intervention complications or disease progression. The role of echocardiography is indispensable in the entire spectrum of RHD management.
SIPA in 10 milliseconds: VWF tentacles agglomerate and capture platelets under high shear
2022, Blood Advances
Shear-induced platelet aggregation (SIPA) occurs under elevated shear rates (10 000 s⁻¹) found in stenotic coronary and carotid arteries. The pathologically high shear environment can lead to occlusive thrombosis by SIPA from the interaction of nonactivated platelets and von Willebrand factor (VWF) via glycoprotein Ib–A1 binding. This process under high shear rates is difficult to visualize experimentally with concurrent molecular- and cellular-resolutions. To understand this fast bonding, we employ a validated multiscale in silico model incorporating measured molecular kinetics and a thrombosis-on-a-chip device to delineate the flow-mediated biophysics of VWF and platelets assembly into mural microthrombi. We show that SIPA begins with VWF elongation, followed by agglomeration of platelets in the flow by soluble VWF entanglement before mural capture of the agglomerate by immobilized VWF. The entire SIPA process occurs on the order of 10 milliseconds with the agglomerate traveling a lag distance of a few hundred microns before capture, matching in vitro results. Increasing soluble VWF concentration by ∼20 times in silico leads to a ∼2 to 3 times increase in SIPA rates, matching the increase in occlusion rates found in vitro. The morphology of mural aggregates is primarily controlled by VWF molecular weight (length), where normal-length VWF leads to cluster or elongated aggregates and ultra-long VWF leads to loose aggregates seen by others' experiments. Finally, we present phase diagrams of SIPA, which provides biomechanistic rationales for a variety of thrombotic and hemostatic events in terms of platelet agglomeration and capture.
An study on the influence of collagen fiber directions in TAVs performance using FEM
2022, Journal of the Mechanical Behavior of Biomedical Materials
Citation Excerpt :
Its three leaflets, thin and flexible membranes, are the main structures guaranteeing unidirectional flow (Ho, 2009) between the ventricle and the aorta by opening during the ventricular systole and preventing blood backflow into the heart during the rest of cardiac cycle by keeping closed. Over time, the valve leaflets become stiffer and thicker, which could lead to cardiac diseases and ultimately produce aortic stenosis (Sahasakul et al., 1988). A common treatment is the Transcatheter Aortic Valve Implantation or TAVI (Brewer et al., 1977).
Transcatheter Aortic Valve Implantation (TAVI) or Replacement (TAVR) is a promising treatment for aortic valve stenosis, consisting of a procedure to replace a damaged native aortic valve by a bioprosthetic one. This replacement valve control the flow of blood using leaflets that are similar to the ones of a native aortic valve. Commonly manufactured using bovine or porcine pericardium, it is a tissue histologically composed of collagen fibers embedded into a nearly-isotropic matrix, where their distribution makes the pericardium behave as an anisotropic hyperelastic material. Because of such complicated behavior, bioprosthetic pericardium valves are, as expected, sensitive to the distribution and orientation of these fibers in such device.
Therefore, the objective of this work is a thorough systematic study on the influence of these fibers’ distribution. First, a Finite Element model of a bioprosthetic valve is generated; then, a material routine to accurately describe the behavior of pericardium is implemented in a commercial software package; in addition, a dedicated algorithm to specify the direction of fibers is developed. Finally, a systematic study on the influence that fiber orientations have on the overall behavior of the TAV is performed.
As a result of this study, two extreme behaviors are highlighted depending on the preferential orientation of collagen fibers; namely, one with fibers in circumferential direction and the opposite with fibers in an axial orientation. Then, it is concluded that the behavior of fibers in circumferential direction is very sensitive to small variations of the orientation angle, whereas such orientation is not as determining when the aim is to achieve a behavior near to the one corresponding with axial orientation.
Novel bicuspid aortic valve model with aortic regurgitation for hemodynamic status analysis using an ex vivo simulator
2022, Journal of Thoracic and Cardiovascular Surgery
The objective was to design and evaluate a clinically relevant, novel ex vivo bicuspid aortic valve model that mimics the most common human phenotype with associated aortic regurgitation.
Three bovine aortic valves were mounted asymmetrically in a previously validated 3–dimensional-printed left heart simulator. The non-right commissure and the non-left commissure were both shifted slightly toward the left–right commissure, and the left and right coronary cusps were sewn together. The left–right commissure was then detached and reimplanted 10 mm lower than its native height. Free margin shortening was used for valve repair. Hemodynamic status, high-speed videography, and echocardiography data were collected before and after the repair.
The bicuspid aortic valve model was successfully produced and repaired. High-speed videography confirmed prolapse of the fused cusp of the baseline bicuspid aortic valve models in diastole. Hemodynamic and pressure data confirmed accurate simulation of diseased conditions with aortic regurgitation and the subsequent repair. Regurgitant fraction postrepair was significantly reduced compared with that at baseline (14.5 ± 4.4% vs 28.6% ± 3.4%; P = .037). There was no change in peak velocity, peak gradient, or mean gradient across the valve pre- versus postrepair: 293.3 ± 18.3 cm/sec versus 325.3 ± 58.2 cm/sec (P = .29), 34.3 ± 4.2 mm Hg versus 43.3 ± 15.4 mm Hg (P = .30), and 11 ± 1 mm Hg versus 9.3 ± 2.5 mm Hg (P = .34), respectively.
An ex vivo bicuspid aortic valve model was designed that recapitulated the most common human phenotype with aortic regurgitation. These valves were successfully repaired, validating its potential for evaluating valve hemodynamics and optimizing surgical repair for bicuspid aortic valves.

View all citing articles on Scopus

¹: Dr. Sahasakul is a visiting clinician.

View full text

Age-related changes in aortic and mitral valve thickness: Implications for two-dimensional echocardiography based on an autopsy study of 200 normal human hearts

Abstract

Am J Cardiol

JACC

Br Heart J

Cardiol Clin

Am J Pathol

Circulation

Pathology of Cardiac Valves

Echocardiographic measurements in normal subjects: evaluation of an adult population without clinically apparent heart disease

J Clin Ultrasound

Echocardiographic measurements in normal subjects: growth-related changes that occur between infancy and early adulthood

Circulation

Measurements of cardiac size, chamber volumes and valve orifices at autopsy

Johns Hopkins Med J