| Abstract: | The straight back syndrome, consisting of loss of normal upperthoracic spinal curvature associated with cardiac murmurs andradiographic cardiom is considered a form of ‘pseudoheartdisease’ which has been attributed to squashing of theheart in the reduced AP diameter of the chest. During an 18-month period 31 patients referred to a cardiologistwere found to have a straight back. Forty-five relatives weresubsequently examined and 27 were found also to have a straightback. Palpitations and chest pain were the commonest symptoms.On the lateral chest radiograph the distance from the middleof the anterior border T8 to a vertical line connecting T4 andT12 was found to be significantly reduced compared to controls,and a value less than 1·2 cm is indicative of a straightback. Of the 58 subjects with the syndrome, 39 (67 per cent) had clinicaland/or echocardiographic evidence of mitral valve prolapse.Respiratory function testing revealed no significant abnormality. HLA typing showed no association with any particular HLA antigenbut indicates that the straight back syndrome is inherited asan autosomal dominant condition and suggested that the antigenicdeterminants may be located on chromosome 6. We conclude that the straight back syndrome should no longerbe considered a form of pseudoheart disease and patients shouldbe investigated for associated mitral valve prolapse and theirrelatives screened. |
