China
Africa
Explore chapters and articles related to this topic
Cardiovascular system
Published in Jagdish M. Gupta, John Beveridge, MCQs in Paediatrics, 2020
Jagdish M. Gupta, John Beveridge
8.16. Which of the following statements is/are true of atrial septal (septum secundum) defect?The systolic murmur is usually present at birth.The systolic murmur is due to increased flow across pulmonary outflow tract and valve.There is fixed splitting of the second heart sound.The lung fields are plethoric.There is no risk of pulmonary hypertension.
Cardiology
Published in Stephan Strobel, Lewis Spitz, Stephen D. Marks, Great Ormond Street Handbook of Paediatrics, 2019
The aetiology of ASDs is not known, but they are associated with several syndromes such as Holt–Oram; dominant inheritance of ASDs in some families is well recognised. ASD is an acyanotic defect of abnormal communication across the atrial septum with left to right shunting. The defect may occur at different positions in the atrial septum, most commonly in the ostium secundum (70%) at the position of the fossa ovalis after incomplete development of the septum secundum (Figs 5.10, 5.11). Ostium primum defects (~25% of ASDs) occur at the lower part of the atrial septum when the septum primum fails to extend to the endocardial cushions. Sinus venosus defects (5% of ASDs) are located at the top of the atrial septum after failure of absorption of the sinus venosus into the right atrium, the right upper lobe pulmonary vein then often draining into the lower part of the superior vena cava (partial anomalous pulmonary venous drainage).
The circulatory system and hormones
Published in Frank J. Dye, Human Life Before Birth, 2019
In addition, a second partition arises from the wall of the atrial region of the heart, the septum secundum. This crescent-shaped partition has its limbs directed toward where the sinus venosus enters the atrial region of the developing heart. The initial opening of the septum secundum does not close. Rather, the edges of its opening provide a valvular mechanism for the foramen ovale (see Figure 15.4B). This valve is designed so that blood returning from the rest of the body will supply both atria. The necessity for this valve has to do with the flow of blood. In the adult, blood returns to the left atrium from the lungs. However, because of the underdeveloped nature of the lungs during prenatal existence, the lungs supply essentially no blood to the left atrium. Instead, blood is supplied to the left atrium from the right atrium via the foramen ovale. This provides the left atrium with a load to pump, which is necessary for its proper development.
Closing the gap on patent foramen ovale and cryptogenic stroke
Published in Expert Review of Cardiovascular Therapy, 2019
Fahed Darmoch, Yasser Al-Khadra, Homam Mousa Bacha, Mohammad Soud, M Chadi Alraies
Foramen ovale is an anatomical intra-atrial communication between the right and left atria. Normally, in embryonic phase of life inferior vena cava blood flows from right side of the heart to the left atrium through the PFO, avoiding the lungs as part of the normal fetus circulation physiology. During birth, pulmonary circulation increases significantly causing left atrial pressure increment. This difference in atrial pressures pushes the septum premium against the septum secundum and eventually functionally closing the PFO [5]. The spontaneous closure of PFO occurs later in life, but clinical observational studies through autopsy and detailed contrast two-dimensional echocardiography showed that this anatomical closure can be incomplete in 1 out of 4 of every adult [6]. Therefore, PFO theoretically considered a normal anatomic variant and not a pathological finding in the absence of possible paradoxical embolism or other specific clinical conditions.
Amplatzer patent foramen ovale occluder: safety and efficacy
Published in Expert Review of Medical Devices, 2019
Raouf Madhkour, Andreas Wahl, Fabien Praz, Bernhard Meier
The choice of the device size should be made according to the thickness of the septum secundum (SS, cranial part of interatrial septum) as well as the presence and extent of an atrial septal aneurysm (ASA). The length of the PFO tunnel is of little importance. The SS is best seen by transesophageal echocardiography (TEE) using a short axis view cutting the aortic root. The long axis bicaval view (a misnomer as it shows the superior vena cava to the right and the coronary sinus to the left but not the inferior vena cava) can also be used. The 25 mm Amplatzer PFO Occluder fits PFOs without thick SS or ASA. In the presence of one or both of these features (about 10–20%), a larger device (preferably the 35 mm Amplatzer PFO Occluder, or a 30 mm Amplatzer Cribriform Occluder with twin 30 mm disks, initially designed for cribriform atrial septal defects) is recommended [14]. The presence of a long tunnel, a small exit hole, or an ASA remote from the PFO may obviate the need for a larger occluder.
Transcatheters for closure of patent foramen ovales
Published in Expert Review of Medical Devices, 2018
Gianluca Rigatelli, Marco Zuin
The more important to mention include: (1) the fusion between the two septa may be irregular and more than one orifice may be detected; (2) the degree of overlapping between the two septa (defined as tunnel) is variable, and as a result, it is possible to have either a very long or a very short tunnel of the PFO; (3) when septum primum is thin and redundant, it may be excessively mobile and create a aneurysmal fossa ovalis [6]; and (4) the presence of abundant adipose tissue within the infolding septum secundum may result in a very thick and bulky septum [7]. Other important structures that may pose issues with the device delivery and placement are the redundant Eustachian valve and the Chiari network, two embryonic remnants [8]. Based on the anatomic features, we may therefore differentiate simple from complex PFOs, where one or more of the characteristics described in Table 1 are present.