From the Guidelines
Trisomy 21 (Down syndrome) is commonly associated with several cardiac problems, including atrioventricular septal defect (AVSD), ventricular septal defects (VSDs), atrial septal defects (ASDs), patent ductus arteriosus (PDA), and tetralogy of Fallot, as outlined in the 2019 AHA/ACC guideline for the management of adults with congenital heart disease 1. The most common cardiac abnormalities associated with Down syndrome can be identified through early cardiac evaluation with echocardiography, which is recommended for all infants with Down syndrome within the first month of life, even in the absence of symptoms. Some key cardiac problems associated with Trisomy 21 include:
- Atrioventricular septal defect (AVSD)
- Ventricular septal defects (VSDs)
- Atrial septal defects (ASDs)
- Patent ductus arteriosus (PDA)
- Tetralogy of Fallot (TOF) These cardiac issues occur due to abnormal endocardial cushion development during embryogenesis, likely related to the extra genetic material from chromosome 21, which affects normal cardiac development pathways, as described in the 2019 guideline 1. Early detection and management of these cardiac problems are crucial to improve morbidity, mortality, and quality of life in individuals with Down syndrome, and surgical correction is often necessary for significant defects, with timing dependent on the specific abnormality and its severity.
From the Research
Common Cardiac Problems Associated with Trisomy 21 (Down Syndrome)
- Atrioventricular septal defect (AVSD) is widely accepted as a common type of congenital heart defect in trisomy 21 2, 3, 4
- Ventricular septal defect (VSD) is also a common congenital heart defect associated with trisomy 21, with a prevalence of 39.2% in one study 2 and 14%-27% in another study 3
- Secundum atrial septal defect is another common cardiac lesion associated with trisomy 21, with a prevalence of 23.4% in one study 2 and 16%-21% in another study 3
- Tetralogy of Fallot is also associated with trisomy 21, with a high proportion (25.0%) of patients with tetralogy of Fallot also having AVSDs 2
- Pulmonary hypertension is a common complication in patients with trisomy 21 and congenital heart defects, with a high incidence of pulmonary hypertension (69 out of 72 cases with a left-to-right shunt) in one study 4
- Coarctation of the aorta is uncommon in patients with trisomy 21 2
Cardiac Procedural Outcomes in Patients with Trisomy 21
- Cardiac surgical procedures are commonly offered to patients with trisomy 21 and congenital heart defects, with a positive impact on life expectancy for some conditions 3
- Single ventricular anatomy is associated with high mortality in patients with trisomy 21, with a mortality rate of 49% in one study 3
- The outcome of patients with trisomy 21 and atrial septal defect is excellent if they do not have pulmonary vascular disease (PVD), with a survival rate not statistically different from age- and gender-matched controls from the normal population 5
- However, PVD is associated with significant mortality in patients with trisomy 21 and atrial septal defect, with a higher mortality rate in patients with uncorrected defects or severe PVD 5
Hospitalization Outcomes in Adults with Trisomy 21 and Congenital Heart Defects
- Hospitalizations for septal defects in adults with congenital heart disease are common, with 54% of adult congenital heart disease admissions having diagnoses of septal defects 6
- Common co-morbidities in adults with septal defects include arrhythmias, heart failure, and diabetes mellitus 6
- Independent risk factors for mortality in adults with septal defects include presence of VSD, trisomy 21, and pulmonary hypertension 6