Sensor-Enabled 3D Printed Tissue-Mimicking Phantoms: Application in Pre-Procedural Planning for Transcatheter Aortic Valve Replacement
Ayman El-Baz, Jasjit S. Suri in Cardiovascular Imaging and Image Analysis, 2018
The aortic valve is a heart valve situated between the left ventricle (LV) of the heart and the aorta. It functions like a one-way flow controller that allows blood from the LV to be pumped into the aorta but prevents the backflow of the blood. Aortic stenosis (AS), which is a narrowing of the aortic valve opening, is the most common valvular heart disease in developed countries [1]. Advanced age is a major risk factor of the development of AS. Some congenital heart defects, such as a bicuspid aortic valve, can also cause AS. The progression of AS involves a series of deteriorations of the cardiac function, including an elevated LV systolic pressure, LV concentric hypertrophy, an elevated LV diastolic pressure, and a decreased cardiac output. If untreated, AS patients ultimately develop heart failure.
Cardiac Ultrasound
John McCafferty, James M Forsyth in Point of Care Ultrasound Made Easy, 2020
The aortic valve is situated at the junction of the left ventricular outflow tract and the aorta. As described previously, it can be characterised in parasternal long- and short-axis orientations, as well as the apical 5-chamber view. In the context of point-of-care echocardiography, the main aims are to describe the anatomy of the valve and identify if there is valve dysfunction resulting from either aortic stenosis or aortic regurgitation contributing to the clinical presentation. The aortic valve has three cusps (also known as leaflets) behind which the aortic wall bulges into the sinus of Valsalva. The right coronary cusp is located anteriorly, so-called as the right coronary artery arises from the aortic wall behind the valve leaflet. The left and non-coronary cusps are located posteriorly, the aorta behind which giving rise to the left main stem and abutting the interatrial septum respectively. Valve opening can be visually assessed, whereby the valve orifice forms a uniform triangle shape in systole.
Pressure waveforms in the cardiac cycle
John Edward Boland, David W. M. Muller in Interventional Cardiology and Cardiac Catheterisation, 2019
As the left ventricle contracts and left ventricular pressure exceeds that of the aorta, the aortic valve is forced open and blood is ejected from the ventricle. Aortic pressure begins to rise as soon as the aortic valve opens, when ventricular blood enters the aorta. Because the aortic valve is open there is continuity of flow between left ventricle and aorta, and pressure in the two chambers equalises. Thus aortic pressure follows and parallels left ventricular pressure during the ventricular systolic ejection period (Figure 14.4). Both pressures peak at mid-systole then decline when the force of ventricular contraction diminishes. As these pressures fall, left ventricular pressure drops below aortic pressure and the aortic valve closes, ending the left ventricular ejection period and marking the beginning of diastole, called protodiastole. Specifically, protodiastole marks the time between the start of ventricular relaxation and the second heart sound caused by aortic valve closure.
A biomechanical model of the pathological aortic valve: simulation of aortic stenosis
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2020
Marcos Loureiro-Ga, Cesar Veiga, Generosa Fdez-Manin, Victor Alfonso Jimenez, Francisco Calvo-Iglesias, Andres Iñiguez
The aortic valve (AV) is the anatomical structure that regulates the blood flow between the left ventricle in the heart and the systemic circulation through the aorta. Aortic Stenosis (AS) is the main pathology of the AV identified by a narrowing of the AV opening, altering the flow and which can cause several major health problems (Naghavi et al. 2013). It is characterized by progressive fibro-calcific remodelling and thickening of the AV leaflets that can evolve causing severe obstruction to cardiac outflow (Lindman et al. 2013). The process induces an additional effort to the heart, which needs to work harder to pump blood to the body and this extra work may eventually affect the heart muscle. Severe AS is a major cause of morbidity and mortality in the elderly (Freeman and Otto 2005) and with a projected 45% increase in the number of people aged 65 and over in the next 25 years in the EU (Eurostat 2012), a rise in the number of AS disease is expected.
Contemporary Review of the Ross Procedure
Published in Structural Heart, 2021
Vincent Chauvette, Laurence Lefebvre, Marie-Ève Chamberland, Elbert E. Williams, Ismail El-Hamamsy
The aortic valve is often considered a passive structure, which opens and shuts in response to changes in trans-valvular pressures. Instead, the aortic valve, a component part of the aortic root, is a dynamic and living structure with many important functions which contribute to optimizing coronary flow reserve, reducing left ventricular workload during systole and ensuring perfect hemodynamics across the aortic root both at rest and with exercise.9 In addition, aortic valve cusps are covered by a monolayer of endothelial cells, which produce nitric oxide, thereby inhibiting platelet aggregation.10 Along with interstitial cells in the body of the cusps, they can also mount an inflammatory reaction in response to bacterial organisms in the bloodstream, limiting the risk of infective endocarditis in normal aortic valves.2,11,12 Finally, the cellular components allow the valve to repair itself and reorganize its extracellular matrix over a lifetime without wear (~2.5 billion cardiac cycles in a normal lifetime).12
Bicuspid aortopathy – molecular involvement of microRNAs and MMP-TIMP
Published in Biomarkers, 2020
Shiho Naito, Johannes Petersen, Tatiana Sequeira-Gross, Niklas Neumann, Jorge Duque Escobar, Tanja Zeller, Hermann Reichenspurner, Evaldas Girdauskas
Our study population included a total of 65 consecutive BAV patients referred to our institution for elective aortic valve surgery with or without concomitant proximal aortic surgery. Demographics and baseline variables of our study group are summarised in Table 1. Briefly, a relatively young, predominantly male cohort with a low perioperative risk was analyzed. Two-thirds of our study population had predominant aortic valve stenosis, while the remaining 23 (34%) patients presented with an isolated aortic regurgitation. 29 (45%) patients had a simultaneous bicuspid aortopathy, defined as a maximal proximal aortic diameter ≥ 40 mm. Two patients had a unicuspid aortic valve disease with predominant aortic stenosis. Aortic valve replacement was performed in 47 (72%) patients, while the remaining 18 (28%) patients underwent aortic valve repair procedure. The concomitant proximal aortic replacement was required in 25 (39%) patients.
Related Knowledge Centers
- Aorta
- Aortic Sinus
- Bicuspid Aortic Valve
- Pulmonary Valve
- Blood
- Systole
- Heart
- Ventricle
- Heart Valve
- Transposition of The Great Vessels