Dyskinesia, Heterotaxy and Congenital Heart Disease

The goal of this study is to elucidate the possible role of primary ciliary dyskinesia (PCD) in complex congenital heart disease associated with heterotaxy. This study arises from our recent finding of an unexpectedly high incidence (40 percent) of complex congenital heart disease together with heterotaxy in a mutant mouse model of PCD. These findings suggest heterotaxy can arise from mutations causing PCD. Consistent with this, a recent clinical research study showed some patients with PCD have undiagnosed heterotaxy. However, there has not been any clinical study to ascertain if patients diagnosed with heterotaxy may suffer from PCD, the focus of this IRB protocol. These studies are of immediate clinical importance, as heterotaxy patients undergoing surgical correction for complex structural heart defects can become ventilator dependent for unknown causes. A diagnosis of PCD in patients with heterotaxy would significantly alter clinical management strategies that have the potential to significantly improve outcome for heterotaxy patients undergoing high-risk cardiac surgery for complex congenital heart defects.

For this study, we will recruit pediatric subjects undergoing surgery for complex congenital heart defects associated with heterotaxy at Children's National Medical Center. We will also recruit adult patients with heterotaxy heart disease or situs inversus from the Children's National Medical Center and at NIH. In addition, we will recruit patients, ages 2 years and older, seen at the NIH by Dr. Kenneth Olivier with known PCD or Kartagener syndrome and with documentation or high clinical suspicion of heterotaxy or situs inversus into our study. Subjects will be evaluated for PCD using standard operating procedures (SOPs). This will include obtaining airway epithelial tissue samples to assess ciliary motion by videomicroscopy and for assessing defects in ciliary ultrastructure by electron microscopy. In addition, nasal nitric oxide measurements will be obtained, as reduced NO levels are often associated with PCD. All of these procedures will utilize SOPs obtained from approved IRB protocols that are part of a multi-center study at the University of North Carolina (Dr. Michael Knowles) and at the NIH (Dr. Ken Olivier, NIAID). In addition, blood, buccal swab, and saliva samples will be obtained for DNA analysis of candidate genes known to cause heterotaxy and/or PCD. Through these studies, we hope to establish whether mutations causing PCD may contribute to heterotaxy and situs anomalies. Such findings may suggest changes in the standard of care for heterotaxy patients to include the evaluation for PCD, particularly prior to surgery. In addition, the DNA analysis may provide novel insights into the genetic causes for complex congenital heart defects associated with heterotaxy and PCD, allowing the future development of appropriate diagnostic tests for more accurate identification of patients at risk for PCD. Together, the outcome of this study can have significant impact on improving the clinical care for patients with congenital heart disease associated with situs anomalies.

• INCLUSION CRITERIA:

Patients who have diagnosed congenital heart disease, heterotaxy or situs inversus will be asked to participate in this study regardless of sex, age, or race. In addition, patients who have diagnosed PCD or Kartagener syndrome with documentation or high clinical suspicion of heterotaxy or situs inversus will also be recruited to participate in this study. There is no known ethnic or racial predilection for heterotaxy, congenital heart disease, situs inversus, PCD, or Kartagener syndrome.

Exclusion criteria

Certain conditions may preclude specific procedures included in this protocol, but may still allow pertinent parts of the diagnostic evaluation. These conditions/procedures may include: pregnancy/chest radiograph. For reversible conditions, such as acute upper airway infection, significant epistaxis within the prior week (not related to number 2 below), or lower airway infection with uncontrollable coughing, the participant may need to be re-evaluated after resolution. For nasal NO or nasal mucosal scrapings, the following lists the absolute contraindications:

• Anatomic abnormality of the nose or sinuses (e.g. complete sinus blockage or turbinatectomy) that precludes the measurement of nasal NO.
• A severe bleeding diathesis or condition, such as hereditary hemorrhagic telangiectasia syndrome, that may predispose to significant nasal bleeding or result in a severely excoriated nasal mucosa.