Chd awareness month

February is chd awareness month. Love ya Addyson!

Ventricular septal defects: are heart defects that are present at birth (congenital). The normal heart has four chambers. The two upper chambers, known as atria, are separated from each other by a fibrous partition known as the atrial septum. The two lower chambers are known as ventricles and are separated from each other by the ventricular septum. Valves connect the atria (left and right) to their respective ventricles. The aorta, the main vessel of arterial circulation, carries blood from the left ventricle and away from the heart. Ventricular septal defects can occur in any portion of the ventricular septum. The size and location of the defect determine the severity of the symptoms. Small ventricular septal defects can close on their own; (spontaneously) or become less significant as the child matures and grows. Moderately-sized defects can cause congestive heart failure, which is characterized by an abnormally rapid rate of breathing (tachypnea), wheezing, unusually fast heartbeat (tachycardia), enlarged liver (hepatomegaly), and/or failure to thrive. Large ventricular septal defects can cause life-threatening complications during infancy. Persistent elevation of the pressure within the artery that carries blood away from the heart and to the lungs (pulmonary artery) can cause permanent damage to the lungs. The exact cause of ventricular septal defects is not fully understood

patent foramen ovale

Adapted from “Holes in the Heart,” Stroke Connection Magazine, January/February 2011

A hole in your heart would seem to be the very definition of a “problem.” Yet more than a quarter of the population has one, and for most it causes no adverse health effects. In fact, the vast majority of those affected don’t even know it.

There are two kinds of holes in the heart. One is called an atrial septal defect (ASD), and the other is a patent foramen ovale (PFO). Although both are holes in the wall of tissue (septum) between the left and right upper chambers of the heart (atria), their causes are quite different. An ASD is a failure of the septal tissue to form between the atria, and as such it is considered a congenital heart defect, something that you are born with. Generally an ASD hole is larger than that of a PFO. The larger the hole, the more likely there are to be symptoms.

PFOs, on the other hand, can only occur after birth when the foramen ovale fails to close. The foramen ovale is a hole in the wall between the left and right atria of every human fetus. This hole allows blood to bypass the fetal lungs, which cannot work until they are exposed to air. When a newborn enters the world and takes its first breath, the foramen ovale closes, and within a few months it has sealed completely in about 75 percent of us. When it remains open, it is called a patent foramen ovale, patent meaning open. For the vast majority of the millions of people with a PFO, it is not a problem, even though blood is leaking from the right atrium to the left. Problems can arise when that blood contains a blood clot.

A simplified view of a PFO

“Blood clots form in our veins all the time,” said Dr. David Thaler, associate professor of neurology at Tufts University School of Medicine and director of the Comprehensive Stroke Center at Tufts Medical Center in Boston. “These are tiny blood clots of just a few millimeters that travel from all over the body into the vena cava where they enter the right upper chamber of the heart.” From there they are pumped into the right ventricle, from where they enter the lungs. These tiny blood clots (individually called a venous thrombus) get filtered by the tiny capillaries in the lungs, after which the freshly oxygenated blood enters the left atrium, then the left ventricle. From the left ventricle, the blood is pumped out into the miles of blood vessels that feed oxygen and nutrients to every cell in our bodies. “Our lungs normally filter out these tiny clots, but a 2mm thrombus in the brain can cause real havoc,” Dr. Thaler said.

That can happen when someone has a PFO or ASD. “PFOs don’t actually cause strokes, but they provide a portal through which a thrombus might pass from the right to the left side of the circulation,” said Dr. Patrick O’Gara, professor of medicine at Harvard Medical School and executive director of the Shapiro Cardiovascular Center. Depending on whether the clot takes a right or left turn as it exits the heart, it can travel to the brain and cause stroke or TIA. Statistically speaking, the odds of this happening are low, but it can happen.

What’s to be done?

“The greatest myth about PFOs is that they must be closed. The vast majority of them require no treatment,” Dr. O’Gara said. “If someone has one that is related to symptoms, they can be treated with aspirin, warfarin or catheter closure, depending on the circumstances.”

Of course, drugs don’t close the hole, “so the aim of drug treatment is to prevent a clot from forming in the first place,” Dr. Thaler said. Nothing will close it except open-heart surgery or a closure device placed by a catheter threaded from the groin through the veins to the heart.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: