Clinical trial NCT00263120: Effects of Thymectomy During Cardiothoracic Surgery
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Thymectomy and Cardiothoracic Surgery
Lead sponsor: University of California, Los Angeles
Sponsor class: OTHER
First posted: 2005-12-07
Enrollment: 124
Sex: ALL
Maximum age (years): 35
Standard ages: CHILD
ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: child and young adult subjects who have undergone surgery in early childhood for correction or repair related to congenital heart disease enrolled for the observational portion of this protocol only

Brief summary: The thymus is known to be the site of T cell development in humans. Due to its location in the chest in front of the heart, incidental thymecomy is commonly performed during cardiothoracic surgery, especially in infants and children, so that surgeons may gain access to the surgical field. This practice has been considered safe because it was thought that the thymus is inactive after birth. However, recent data using newly developed techniques has demonstrated that the thymus normally is active well into adulthood. In addition, in a previous study (UCLA IRB # 02-03-008-02) we have demonstrated alterations in lymphocyte (T cells) number in individuals who have undergone thymectomy in childhood but we do not know how immunity is affected. We plan to investigate if immune development or immune function later in life is affected by the loss of T cell production caused by thymectomy during cardiothoracic surgical procedures in childhood. At UCLA, a large number of patients are seen who have congenital heart disease and undergo surgical procedures for correction or repair and many children and adults are followed for many years after they have undergone surgical procedures. Subjects for study will be recruited from among these patients.

We propose a study which will examine the number and activity of lymphocytes obtained from blood samples from child and young adult subjects who have undergone surgery in early childhood. We will determine if these subjects have had complete thymectomy in the past using CT or MRI (obtained during routine care) or, for subjects who are having cardiothoracic surgery, by visualization of thymic tissue during the procedure. In addition we will give vaccination for a common viral illness (hepatitis A) and measure immune responses to it (from a blood sample). As part of this study, we will ask for medical information consisting of a history of congenital cardiac disease and other diagnoses (such as asthma), a history of infections and hospitalizations, and information about immunizations. We will also ask about a list of specific symptoms which will give us information about the function of the immune system.


Eligibility criteria: Inclusion Criteria:

* Age: birth to 35 years.
* Planning cardiac surgical procedure at UCLA Medical Center.
* For subjects with a history of prior cardiothoracic surgery: undergoing CT or MRI evaluation prior to reoperation.

Exclusion Criteria:

* Unable to travel to UCLA Medical Center for follow up blood tests (infants and young children in longitudinal study)
* Known thymus/immune deficiency disorder (i.e. DiGeorge Syndrome)

Primary outcomes:
measure: immune dysfunction
timeFrame: late
Secondary outcomes:
Other outcomes:
Locations:
city: Los Angeles
country: United States
facility: UCLA Adult Congenital Heart Disease Clinic
state: California
Study officials:
affiliation: Pediatric Cardiology, UCLA
name: Nancy J. Halnon, M.D.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Halnon NJ, Jamieson B, Plunkett M, Kitchen CM, Pham T, Krogstad P. Thymic function and impaired maintenance of peripheral T cell populations in children with congenital heart disease and surgical thymectomy. Pediatr Res. 2005 Jan;57(1):42-8. doi: 10.1203/01.PDR.0000147735.19342.DE. Epub 2004 Nov 5.
citation: Halnon NJ, Cooper P, Chen DY, Boechat MI, Uittenbogaart CH. Immune dysregulation after cardiothoracic surgery and incidental thymectomy: maintenance of regulatory T cells despite impaired thymopoiesis. Clin Dev Immunol. 2011;2011:915864. doi: 10.1155/2011/915864. Epub 2011 Jul 6.