Abstract 4147633: Structural and Electrophysiological Cardiac Changes in Children with Osteogenesis Imperfecta (OI)

Introduction: Osteogenesis imperfecta (OI) is an inherited type 1 collagen disorder leading to bone fragility and increased fractures. Cardiovascular disease is the leading cause of death of adults with OI, but studies on cardiac changes from this collagen defect in children are sparse. We aim to fill this gap by assessing changes in EKG and echocardiogram (ECHO) variables in children with OI. Hypothesis: Children with OI will exhibit arrhythmogenic EKG changes and/or ECHO abnormalities which will precede changes that are documented in adults. Methods: 53 children with OI receiving care at Children’s Mercy-Kansas City were identified via ICD-10 codes. 64 with Duchenne Muscular Dystrophy (DMD, expected cardiac abnormalities) and 55 with non-accidental trauma (NAT, no expected cardiac abnormalities) served as controls. We specifically compared the most recent EKG and ECHO metrics extracted from medical charts by Kruskal-Wallis testing. Results: EKG: Children with OI differed from both NAT and DMD. OI had shorter median PR intervals (p<0.001) plus longer median QRS (p<0.001) and QTc intervals (p=0.002) than NAT. DMD had the shortest PR and longest QRS and QTc (see Table). Echo: The three groups showed no difference in systolic/diastolic BP or LV thickness. However, OI differed from NAT and/or DMD in other metrics. OI had higher end diastolic volume (p<0.001), end systolic volume (p<0.001) and stroke volume (p<0.05) than NAT, but lower values than the DMD group. Similarly, OI children had higher LV mass and LV internal diastolic and systolic diameters than NAT, but lower than DMD (p<0.001). OI LVOT diameter and Aortic root diameter were lower than NAT, but not as low as DMD (p<0.05 and p<0.001, respectively). Conclusion: Children with OI exhibit EKG and ECHO abnormalities that are similar to but less severe than for DMD, a group in which cardiovascular abnormalities are well documented. These abnormalities may be predictive of arrythmia/sudden cardiac death and/or functional decline in heart function. Our data suggest that OI children could benefit from ongoing routine cardiology studies along with orthopedic/metabolic management. Future studies would assess effects of age and OI treatments on cardiac abnormalities.