Background: Osteogenesis Imperfecta (OI) refers to a phenotypically and genetically heterogeneous group of Mendelian disorders that typically manifest with increased bone fragility, recurrent fractures, bone deformities, short stature, hearing loss, and joint laxity.
Objective: To assess the effect of treatment with bisphosphonates on cardiac and pulmonary functions in patients with Osteogenesis Imperfecta.
Patients and Methods: This is a cross-sectional study was conducted on 28 OI patients; echocardiography and pulmonary function tests of these patients were studied at the time of recruitment. Sixteen of the studied subjects had baseline echocardiography conducted before starting bisphosphonate therapy. The effect of bisphosphonate therapy on cardiac anatomy and functions was studied by comparing different echocardiographic parameters before and after bisphosphonate therapy in the studied subjects.
Results: Pulmonary function test results showed that ten patients (38.5%) had restrictive lung disease, two patients (7.7%) had mixed obstructive and restrictive lung patterns, and 14 patients (53.8%) had normal pulmonary function tests. Echocardiography of the studied subjects showed that two patients (7.1%) had increased AO/LA ratio, one patient (3.6%) had hypertrophied IVSd, three patients (10.7%) had hypertrophied IVSs, seven patients (25%) had dilated LVEDD, and four patients (14.3%) had dilated LVESD. All patients had normal systolic function. Five patients (17.9%) had mild mitral, tricuspid and aortic valves regurge. A significant decrease in the median aortic z-score and a significant increase in the median z-scores of IVSd, IVSs, LVEDD, LVESD, LVPWs and LVPWd were observed after 12 months of bisphosphonate therapy. Meanwhile, there was no significant difference of mean EF, FS & AO/LA ratio before and after treatment. Two cases had impaired EF at baseline and after treatment EF became normal.