Zofran Heart Defects

Structural heart defects such as valve defects have been linked to Zofran use during pregnancy.

(UPDATE: Levin Simes Abrams is not currently investigating new cases regarding Zofran or Ondanestron for failure to warn, when a manufacturer fails to update product labels or drug warning labels to note risks they know or should have known. This page is for informational purposes, please speak with a medical professional regarding any medication change or for medical care.

Department of Justice press release regarding the $3 billion settlement for criminal fraud for illegal marketing, including kickbacks to doctors to prescribe drugs.)

Zofran doubles the risk of congenital heart defects

Zofran during pregnancy can cause heart defects such as VSD or “hole in the heart” defects.

Zofran Pregnancy Heart Defects

Use of Zofran (Ondansetron) during pregnancy was investigated by researchers at the Copenhagen University at the Department of Clinical Pharmacology and was found to increase the risk of cardiac birth defects.  If you or a loved one used Zofran during pregnancy, and your child experienced a birth defect, contact a lawyer at Levin Simes Abrams.

What heart defects are caused by Zofran?

This is a list of heart defect birth defects potentially caused by Zofran:

  • Atrial Septal Defect (ASD)
  • Ventricular Septal Defect (VSD)
  • Atrioventricular Septal Defect (AVSD)
  • Coarctation of Aorta (COA)
  • Double Outlet Right Ventricle (DORV)
  • Transposition of Great Arteries (TOGA)
  • Ebstein’s Anomaly
  • Hypoplastic Left Heart Syndrome (HLHS)
  • Pulmonary Atresia
  • Single Ventricle
  • Tetralogy of Fallot
  • Total Anomalous Venous Return (TAVR)
  • Tricuspid Atresia
  • Truncus Arteriosus
  • Bicuspid Valve

A Closer Look at the Studies

Researchers searched the Denmark Medical Birth registry for all women who gave birth from 1997 to 2010, identifying 903,207 births in the study period. Of those births, 1,368 women took Zofran during their first trimester.  The adverse effect of Zofran use during pregnancy was clearly demonstrated in this study, as shown in the chart above.

Of those women using Zofran during their first trimester of pregnancy, 61 out of 1,368 (4.7 percent) gave birth to children with congenital malformations.  Specifically, the study found that there was a 160 percent increase in heart defects in infants born to women who took Zofran during pregnancy compared to those who did not.

The dangers of Zofran during pregnancy are even more pronounced with regard to the increased risk for septal birth defects.  The study found that children born to women taking Zofran during their first trimester were 210% more likely to have Atrial Septal Defects (ASD), 230% more likely to have Ventricular Septal Defects (VSD), and 480% more likely to have Atrioventricular Septal Defects (AVSD).

The increased risk for such septal defects amongst women taking Zofran during pregnancy were found to be statistically significant – that is, the increased risk amongst women taking Zofran was not a result of chance.  GlaxoSmithKline, the manufacturer of Zofran, profited from years of promoting off-label usage to treating nausea during pregnancy, and put thousands of pregnant women and their infants at risk.   Despite these astonishingly high risks for birth defects, GlaxoSmithKline has never provided warnings to these women or their prescribing doctors.   These risks thus remain hidden from pregnant women today.

Learn More about Cardiac Birth Defects Caused by Zofran Pregnancy

What is an Atrial Septal Defect Caused by Zofran Pregnancy?

An Atrial Septal Defect (ASD) is heart defect that occurs when blood in the heart flows from one atria into another. In a normal heart, this is not possible as the atrias are separated by the inter-atrial septum.  It is this incomplete atrial septum that gives name to the birth defect – Atrial Septal Defect (ASD).

Atrial Septal Defects can be small and go unnoticed, especially if the defect is not significantly pronounced. The amount of blood that flows through the defect determines the severity of the condition, and defects allowing for flow from the right atrium to the left atrium (a “right-to-left”) are considered more severe.  This flow is typically referred to as a “shunt.”

Many children are diagnosed in utero or shortly after birth. Confirmation of the defect can be performed using ultrasonograph or auscultation testing. As most defects – even medium sized holes – produce no symptoms, it is unlikely to recognize an ASD or symptoms of an ASD without medical tests.



What are the types of Atrial Septal Defects?

There are three main types of Atrial Septal Defects:

  • Sinus Venosus: The defect is located in the upper part of the atrial septum. These defects are uncommon and will not close on their own.
  • Secundum: The defect is located in the middle part of the atrial septum. These defects are more common and two out of three of these holes will close on their own without surgery.
  • Primum: The defect is located in the lower part of the atrial septum. These defects are uncommon and will not close on their own.

If the defect is not likely to close on its own – as occurs in the majority of cases of Secundum Atrial Septal Defects affecting the middle portion of the atrial septum – surgery may be required. Without surgery and without closing the hole in the heart, flow from the right side of the heart can create heart problems for the child, manifesting as the child grows into adulthood, particularly after the age of 30.

What are the complications from Atrial Septal Defects?

There are several potential complications from ASD if left surgically untreated. These include:

  • Arrhythmias: Blood flow from the right atrium to the left atrium can enlarge the atrium, which over time can lead to irregular heartbeats (arrhythmias).
  • Pulmonary Hypertension: Pulmonary Hypertension (PH) damages the arteries and vessels in the lungs, producing an enlarged stiff tissue that reduces the ability of blood to flow. Surgical intervention for ASD produces better results if it occurs prior to the onset of pulmonary hypertension.
  • Heart Failure: Right heart failure can occur when the right side of the heart must work harder than the left due to the extra blood it is pumping into the lungs. Right heart failure can result and reduce the effectiveness of this part of the heart.
  • Stroke: Normally, any small clots that naturally occur in your heart are cleaned by the lung and cannot enter the body and travel through the body. However, with the presence of an uncorrected ASD a blood clot has the potential to travel from the right atrium directly to the left atrium and into the bloodstream.  A clot that travels to the brain and blocks blood flow to the brain is known as a stroke. A stroke can have devastating permanent affects.

What is the treatment for Atrial Septal Defects?

Some cases of ASD are not severe and the holes in the heart will close on their own.  This occurs primarily in Secundum Defect cases affecting the middle portion of the septum.  For holes that do not close, more severe cases will require surgery to prevent the onset of complications including stroke, heart failure, hypertension and arrhythmia, which can affect adults with untreated ASD.

What is a Ventricular Septal Defect Caused by Zofran Pregancy?

A Ventriular Septal Defect is a hole in the septum between the right and left ventricles.  This is similar to the Atrial Septal Defect except it affects the lower ventricles chambers instead of the upper atrium chambers. A child developing will develop this section of the heart around approximately week 8, and defects in development at this stage will result in ventricular septal defects or VSD.

A defect between the ventricles allows blood to pass through the hole or opening in the heart, and oxygen-poor blue blood from the right ventricle is mixed with oxygen-rich blood from the left ventricle when it enters into the right side.


What are the types of ventricular septal defect?

Commonly ventricular septal defects are divided into four types:

  • Membranous VSD: An opening in the upper portion of the ventricular septum, near the tricuspid and aortic valves. This type of VSD rarely closes on its own and typically requires surgical intervention.
  • Muscular VSD: An opening in the muscular portion of the ventricular septum, this type of VSD will typically close on its own without the need for surgical intervention.
  • Conal Septal VSD: An uncommon form of VSD, this affects the ventricular septum underneath the pulmonary valve.
  • Atrioventricular Canal Type VSD: This variation of VSD affects the atrioventricular canal. The hole is located adjacent to the mitral and tricuspid valves and requires surgical intervention to repair.

What are the Treatment Options for Ventricular Septal Defects?

Some types of VSD can spontaneously close, such as muscular VSD.  Other types of VSDs, including membranous VSD and Atrioventricular Canal Type VSD, require surgical intervention as they do not resolve on their own.

Diagnosis of VSD can be done through x-ray testing, electrocardiogram (ECG) testing,echocardiogram (echo) testing, or via a cardiac catheterization.

If treatment is required, treatment may include prescription medication, surgical repair, or interventional cardiac catheterization. Medications to treat VSD include Digoxin, Diuretics, and ACE inhibitors.  Surgery involves repairing and closing the hole in the septum, which is typically sealed using either stitches or a patch.  Interventional cardiac catheterization involves sedating the child, inserting a tube into the heart via the groin, and then inserting a “septal occluder” via the tube to seal the hole in the heart and repair or seal the ventricular septal defect permanently.

What are the symptoms of Ventricular Septal Defects?

Symptoms for VSD can occur even in infancy, which is not typically seen in other types of septum defects such as atrial septum defects (ASD).  These symptoms include:

  • Poor weight gain
  • Lack of desire to feed
  • Rapid, congested, or heavy breathing
  • Fatigue
  • Sweating

Symptoms for VSD should be examined by a health care professional, and can seem similar to other heart conditions or other conditions.

What is an Atrioventricular Septal Defect Caused by Zofran Pregancy?

An Atrioventricular Septal Defect (AVSD) is a defect in the atrioventricular septum of the heart. An abnormal or incomplete fusion of the endocardial cushions (the superior and inferior cushion) can cause partial or complete forms of AVSD.

In a partial AVSD, the defect does not cause direct intraventricular communication, but there is a defect in the inferior or primum part of the atrial septum.

In a complete AVSD (CAVSD), the defect involves either or both the superior or inferior bridging leaflets resulting in a large ventricular component beneath the AV valve. This produces a large hole in the heart, between the upper ventricles and the lower chambers of the heart. The severity of this condition depends on whether the valve allows flow from the right or left atriums into their respective right or left ventricle. This is known as an “unbalanced flow.”

Atrioventricular Septal Defects are also referred to as “common antrioventricular canal (CAVC), or an “endocardial cushion defect.”


Treatment for Atrioventricular Septal Defects

Treatment of AVSD typically involves surgery to close the atrial and ventricular defect(s) and restore correct flow.  In the case of infants born with AVSD, surgery is typically postponed for 3-6 months to allow for the child to grow large enough to make surgery on the heart easier.  The surgery is typically delayed as long as possible given the severity of the defect, and sometimes can be delayed as long as one to two years.

What is a “Hole in the Heart” Defect?

A “hole in the heart” defect is a term used to describe many of the heart defects listed on this page.  A hole in the heart occurs in an atrial septal defect when there is a hole in the septum separating the right and left atrium.  Holes and defects in other portions of the heart can be diagnosed as atrioventricular septal defects or ventricular septal defects.

(UPDATE: Levin Simes Abrams is not currently investigating new cases regarding Zofran or Ondanestron for failure to warn, when a manufacturer fails to update product labels or drug warning labels to note risks they know or should have known. This page is for informational purposes, please speak with a medical professional regarding any medication change or for medical care.)