00:00 / 00:00
Bundle branch block
Pulseless electrical activity
Atrioventricular nodal reentrant tachycardia (AVNRT)
Premature atrial contraction
Long QT syndrome and Torsade de pointes
Premature ventricular contraction
Coronary steal syndrome
Coarctation of the aorta
Polycystic kidney disease
Renal artery stenosis
Peripheral artery disease
Subclavian steal syndrome
Superior mesenteric artery syndrome
Human herpesvirus 8 (Kaposi sarcoma)
Chronic venous insufficiency
Deep vein thrombosis
Acyanotic congenital heart defects: Pathology review
Aortic dissections and aneurysms: Pathology review
Atherosclerosis and arteriosclerosis: Pathology review
Cardiac and vascular tumors: Pathology review
Cardiomyopathies: Pathology review
Coronary artery disease: Pathology review
Cyanotic congenital heart defects: Pathology review
Dyslipidemias: Pathology review
Endocarditis: Pathology review
Heart blocks: Pathology review
Heart failure: Pathology review
Hypertension: Pathology review
Pericardial disease: Pathology review
Peripheral artery disease: Pathology review
Shock: Pathology review
Supraventricular arrhythmias: Pathology review
Valvular heart disease: Pathology review
Vasculitis: Pathology review
Ventricular arrhythmias: Pathology review
Ventricular septal defect
0 / 11 complete
0 / 3 complete
ventricular septal defect p. 305
congenital rubella p. 306
cri-du-chat syndrome p. 62
Down syndrome p. 306
fetal alcohol syndrome p. 306
heart murmurs p. 298
outflow tract formation p. 288
pansystolic murmur in p. 297
If you look at the heart, you’ve got the right and left atrium up top, and the right and left ventricles down low. Each of these pairs is separated by a wall, called a septum. A ventricular septal defect is when this lower wall—the ventricular septum—has a gap in it after development.
The septum is formed during development as this muscular ridge of tissue grows upward from the apex, or the tip, and then fuses with a thinner membranous region coming down from the endocardial cushions. Voila—two separate chambers. If these don’t fuse though, then a gap is left between the two chambers; in other words, a ventricular septal defect, or VSD. The majority of cases are caused by a defect in the membranous portion of the septum.
Among babies, VSDs are actually the most common congenital defect overall, but 30 to 50% of VSDs can spontaneously close during childhood, which makes ventricular defects less common with adults. VSDs are associated with fetal alcohol syndrome and Down syndrome, and are often associated with other cardiac deformities as well.
Alright so now let’s check out what happens with blood flow, now that there’s this opening between the two ventricles. I’m going to actually switch to this super duper simplified heart instead, just because it’s easier to show what’s going on with blood flow. Alright, so deoxygenated blood comes from the body to the right atrium, and then flows down into the right ventricle, where now it can either be pumped out to the lungs, as normal, or pop over to the left ventricle. Since the pressure on the left side of the heart is actually higher than on the right, and blood likes to flow from high pressure to low pressure, it actually prefers to just keep going on to the lungs. When oxygenated blood comes back from the lungs to the left atrium, and then the left ventricle, now again, it’s got two choices: it can either be pumped out to the body, or flow over to the right ventricle through the gap. Since now it’s in the left ventricle which has higher pressure, some of the blood flows over to the lower-pressure right ventricle, so a left-to-right shunt has been set up, where oxygenated blood takes an extra trip to the lungs.
Ventricular septal defect (VSD) is a type of congenital heart defect that affects the septum, the wall that separates the two ventricles of the heart. In VSD, there is an abnormal opening in the septum that allows blood to flow between the two ventricles. This results in increased blood flow to the lungs, causing pulmonary hypertension and, in severe cases, heart failure. VSD is typically diagnosed during infancy or childhood, and imaging tests such as echocardiography or cardiac catheterization may be used to confirm the diagnosis. Treatment options for VSD depend on the size and location of the defect, and can include medications, surgery, or catheter-based procedures to close the hole and restore normal blood flow in the heart.
Copyright © 2023 Elsevier, its licensors, and contributors. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
Cookies are used by this site.
USMLE® is a joint program of the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners (NBME). COMLEX-USA® is a registered trademark of The National Board of Osteopathic Medical Examiners, Inc. NCLEX-RN® is a registered trademark of the National Council of State Boards of Nursing, Inc. Test names and other trademarks are the property of the respective trademark holders. None of the trademark holders are endorsed by nor affiliated with Osmosis or this website.