Effection of thoracic curve on cardiac structure and function in patients with adolescent idiopathic scoliosis

English Keywords:Adolescent idiopathic scoliosis  Echocardiography  Cardiac structure and function

English Abstract:

  【Abstract】 Objectives: To investigate the features of cardiac structure and function in adolescent idiopathic scoliosis(AIS) patients, and to further discuss the influence of cardiac structure and function on related factors with scoliosis of main thoracic. Methods: From June 2008 to June 2011, the clinical data of 374 AIS patients receiving spinal correction in the department of spine surgery of Drum Tower Hospital affiliated to Nanjing University were reviewed in this study. All patients underwent a full clinical examination. 374 of AIS patients without congenital heart disease(15) were selected, who were all females and subjected to main thoracic. The mean age of these patients was 14.9±1.8 years, ranging from 10 to 18 years. All patients underwent echocardiography for routine screen of cardiac abnormities, and echocardiographic records of 374 patients were available. All these clinical data and imaging records were reviewed. The cardiac structure and function included interventricular septum thickness in end diastole(IVSTD), left ventricular inner diameter in end dias?鄄tole(LVDD), left ventricular inner diameter in end systole(LVIDS), posterior wall of left ventricle in end diastole(LVPWD), diameter of aortic root(DAR), left atrial dimension(LAD), ejection fraction(EF), diameter of arteria pulmonalis(DAP), left ventricular peak systolic blood flow velocity in early diastole(E), left ventricular peak systolic blood flow velocity in end diastole(A) and aortic flow velocity(AV). The patients were classified according to the coronal angle and thoracic kyphosis to compare the indexes related to cardiac structure and function. Through the multiple linear regression analysis to the independent influence of cardiac structure and function. Results: Cardiac structure and function indexes（LVDD, LVIDS, IVSTD, DAR, LVPWD, LAD, DAP, EF, E, A, E/A and AV） were all in the normal level. The patients were classified into 2 groups, which were Cobb′s angle ≤70° and >70° according to the Cobb′s angle in coronal plane. There were significant differences in the LVDD, LVIDS, AV between 2 groups(P<0.05); no significant differences in the IVSTD, DAR, LVPWD, LAD, EF, E, A and E/A were noted between 2 groups(P>0.05). When classifying the patients into 3 groups, which were Cobb′s angle <10°, 10°-40° and >40° according to the Cobb′s angle in sagittal plane, there was significant difference in the LVDD between the group of <10° and the group of 10°-40°(P<0.05); significant differences in the IVSTD, LAD and DAP between the group of <10° and the group of >40°(P<0.05) were noted; there was significant difference in the EF between the group of 10°-40° and the group of >40°(P<0.05); there were no significant differences in the LVIDS, DAR, LVPWD, E, A, E/A and AV in 3 groups(P>0.05). It was found that age and coronal angle were the independent influence factors of LVDD and LVIDS(P<0.05). The standard partial regression coefficient of coronal angle were -0.150 and -0.162; The standard partial regression coefficients of age were 0.139 and 0.146. Standardized partial regression coefficient absolute value of the Cobb′s angle in coronal plane was greater than the age. It was found that age was also the independent influence factor of IVSTD and DAR(P<0.05). The standard partial regression coefficients of age were 0.271 and 0.272. Conclusions: Cardiac structure and function indexes are overall basically in the normal range in AIS patients. However, coronal deformity and thoracic kyphosis will influence the cardiac structure. The inner diameter of left ventricle decreases with the increasing angle of coronal plane.