Isolated ventricular septal defect (VSD) is a well know congenital heart anomaly. If discovered in infancy or early childhood surgical intervention can be of necessity depending on the size of the defect, to assure a healthy adulthood. The long-term results of surgical closure of VSD in childhood are good and after surgery the children are considered as equally healthy and physically fit as their peers. However, there is inconsistency in data regarding follow-up on this group of patients, in relation to exercise capacity as a measure of the cardiopulmonary function. To further approach this matter the post-operative cardiac factors of these patients have to be investigated.

With this study the investigators intend to examine the long-term outcome on cardiac output after heart surgery in VSD-patients. It presents an opportunity to also evaluate the correlation between cardiac output determined by gas-exchange and by MRI. The overall objectives of this study are to 1) examine whether VSD-operated patients have reduced cardiac output during exercise in comparison with matched controls, and furthermore 2) to evaluate a correlation between cardiac output measured by MRI and cardiac output determined by gas-exchange.

The project is designed as a long-term follow-up and method study. A cohort of 20 children who in the 1990's underwent surgical closure of a congenital VSD will be asked to participate in this study. An equal amount of healthy young adults, will function as control group. Each participant will complete two different exercise tests, a MRI of the heart during lower body exercise on a supine ergometer bicycle, and a Supine ergometer bicycle exercise test. This data can be used for comparing cardiac output between the test groups, and furthermore it allows an evaluation of the correlation between the two methods.

VSD is as described, the most common congenital heart anomaly. If not intervened with in childhood, it can cause severe heart complications later in life. It is unclear whether this intervention can cause long-term impact on patients exercise capacity, and for that reason it is of great importance that we strive for improving our knowledge of the long-term postsurgical outcome after VSD-closure.

Inclusion Criteria:

• Patients: Surgical correction of VSD between 1990 and 1995
• Controls: 18-25 years old, with no medical records of heart disease

Exclusion Criteria:

• Missing journal
• Operation by ventriculotomy
• Other congenital anomalies
• Metallic implants or foreign objects
• Pregnancy

Of 182 children who in the years 1990 to 1995 underwent surgical closure of a congenital VSD at Aarhus University Hospital (AUH), Denmark, a small group of 20 is randomly selected to participate. These children form a homogenous group of patients comparing surgeons, anesthetists, surgical procedures and post-surgical period. An equal amount of healthy controls, matched on age and gender, form the control group.