Abstract 1981: Spectrum of Congenital Heart Disease in Family Members of Adults With Tetralogy of Fallot
BACKGROUND Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease (CHD) with a complex genetic etiology. Our objective was to examine the family history of CHD in a large cohort of adults with TOF.
METHODS Probands with TOF without a known genetic syndrome were interviewed by trained clinical staff for a family history of CHD and pedigrees were constructed. Where possible, specific types of CHD were confirmed by chart review. CHD was designated unspecified when a diagnosis could not be ascertained, but patients were certain of the congenital status and/or that corrective surgery was performed.
RESULTS A total of 455 probands with TOF were included (250 males, 205 females; mean age 38 ± 13 years). There was a positive family history of CHD in 88 probands (19%), of whom 20% (18/88) had more than 1 affected relative. Of the 116 affected relatives, 35% (n=41) were first degree, 29% (n=34) second degree, 20% (n=23) third degree and 16% (n=18) were more distant relatives. TOF was found in 29 relatives of 23 probands (concordance rate of 25%). The spectrum of CHD in first and second degree relatives is presented in the Table⇓ below.
CONCLUSION A family history of CHD is common in adults with TOF. The results show that TOF, like other conditions of complex genetic etiology, has variable expressivity in affected relatives. The segregation pattern may provide clues to specific genetic etiologies of TOF in families.