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One important stimulus to over-testing is the anxiety in-separable from clinical practice. There are few certainties inthe diagnostic process, and the comforting (if sometimesspurious) precision of laboratory results has the same appealto the uneasy clinician as a life-belt to the weak swimmer.Discussion and advice may act as a better-and
cheaper-source of support. There are other less desirablereasons for excessive testing, of course. "Just in case" tests areordered by the junior lest he be surprised by a demand for aresult by his consultant-martinet. "Routine tests" (exposedby Sandler) are ordered when habits are unthinkinglyestablished. Such habits may account for the high incidenceof repeat testing in the Harvard study.
It is not only the junior doctor who orders unwisely,however. There are "ah-hah" tests; measurements known tobe abnormal in certain conditions, which are ordered evenwhen the diagnosis is established in order to satisfy curiosityor to advertise the cleverness of the clinician. An unwisesearch for unlikely rarities which cannot be treated is an ex-pensive hobby, too. Haste and overwork also lead to over-investigation. All too readily the clinician may order an in-vestigation when a more careful clinical history or physicalexamination would serve better, or where careful clinicalreview after a period would give the answer. ("Time is thebest-and cheapest-test we have").
All these errors are susceptible to thought. Every respon-sible clinician does think whether the test he is about to orderis of real value to the patient, provided he has the time and theinformation to obtain the right answer. Unit discussions andcase-record reviews will assist. As the laboratory repertoiregrows we may need computer-based information schemes, orautomatic feedback, to tell the clinician the probability of atest’s providing useful data. Until such systems are evolvedwe can only urge thought before any request card is com-pleted.
TWENTY years ago a new syndrome appeared on themedical horizon, the straight-back syndrome.l,2 It had twomain features-loss of the normal curvature of the upper dor-sal spine, leading to a decreased antero-posterior diameter ofthe chest with apparent squashing of the heart; and a systolicmurmur heard over the base of the heart (originally attributedto torsion of the great vessels). Routine chest radiographysuggested cardiac enlargement. Rawlings’ original descrip-tions were soon backed by others, 3-8 and there were sugges-tions that this syndrome could be regarded as "pseudo-heart-disease" since haemodynamic function and heart size werenormal and the murmur was of extracardiac origin. The
1. Rawlings MS. The ’straight back’ syndrome, a new cause of pseudo-heart disease Am JCardiol 1960, 5: 333-38.
2. Rawlings MS. Straight back syndrome: a new heart disease. Dis Chest 1961; 39:435-43
3. Serratto M, Kedzi P. Absence of the physiological dorsal kyphosis. Ann Intern Med1963; 58: 938-45.
4. Datey KK, Deshmuki MM, Engineer SD, Dalvi CP Straight back syndrome. Br HeartJ 1964; 26: 614-19.
5. De Leon AC, Perloff JK, Twigg H, Majd M. The straight back syndrome. Clinical car-diovascular manifestations. Circulation 1965; 32: 193-203.
6. Twigg HL, De Leon AC, Perloff JK, Majd M. The straight back syndrome:radiological manifestations. Radiology 1967, 88: 274-77
7. Rubenstein HJ, Johnson RB. The effect of external compression on the murmur andthrill of the straight back syndrome. Am Heart J 1967; 74: 88-91.
8. Siegel JS, Schechter E. The straight back syndrome. Another cause of innocent systolicmurmurs. Am J Med 1967; 42: 309-13.
symptomless syndrome was judged benign and compatiblewith normal employment and life expectancy. Of course,some patients with rheumatic or congenital heart disease hadstraight backs, but here the signs of organic heart diseasewould exclude the diagnosis of straight-back syndrome.9 Another report, however, challenged the origin of the mur-mur, suggesting that it was actually intra-cardiac in origin,with no significant cardiac compression. 10Over the same period a second syndrome began to attract
attention-the "mitral-valve-prolapse" syndrome in whichsystolic clicks and murmurs arose from a floppy mitralvalve." Surprisingly, a high percentage of mitral-valve-prolapse patients proved to have some form of spinal deformi-ty including pectus excavatum, scoliosis, and straightbacks. 12-14 In a prospective study of mitral-valve prolapse inpatients with thoracic skeletal abnormalities, Udoshi et al. 15
found that half of those with straight backs also had mitral-valve prolapse. They suggested that both abnormalities
might be linked developmentally as a single connective tissuedefect, since the mitral valve undergoes final differentiationat the same time as the vertebral column and thoracic cage are
being chondrified and ossified. This combination of abnor-malities has also been regarded as a forme fruste of Marfan’ssyndrome.14 The inevitable conclusion was that no longershould "pseudo-heart-disease" be diagnosed until mitralvalve prolapse had been excluded. Further evidence for theassociation between skeletal abnormality and mitral valveprolapse has been offered by Davies and colleagues,16 whowere asked to see 31 people with straight back syndrome andwho identified the condition also in 27 near relatives. Of the58 subjects, two-thirds had evidence of mitral-valve prolapse.There were no important respiratory abnormalities. Noassociation was found between any particular HLA antigenand the straight-back syndrome, and the findings pointed toan autosomal dominant disorder. (It is noteworthy that mitralvalve prolapse may also be a familial disorder with anautosomal dominant inheritance:11 perhaps the same
chromosome is involved.)What is the message in 1981 for the doctor faced with a
patient who has a systolic murmur and X-ray evidence of astraight back? No longer is "pseudo-heart-disease" a suitablelabel; no longer should murmurs be regarded as due topressure on the heart, but rather as due to associated mitralvalve prolapse; and anyone referred with straight-back syn-drome should be evaluated for mitral-valve prolapse. If this isthe cause of the murmur, investigation need to be taken nofurther, sparing the patient and relatives much anxiety. Forthe research worker, the linking of these two disorders mayhelp to unravel some of the curious relationships betweendevelopmental abnormalities and cardiac disease.
9. Gooch AS, Maranhao V, Goldberg H. The straight thoracic spine in cardiac diagnosisAm Heart J 1967; 74: 595-602.
10. Wennewold A, Stage P. The straight back syndrome related to intracardiac murmursDan Med Bull 1970; 17: 24-27.
11. Editorial. The floppy mitral valve. Lancet 1979; i: 138-39.12 Scampardonis G, Yang SS, Maranhao V, Goldberg H, Gooch AS Left ventricular ab-
normalities in prolapsed mitral leaflet syndrome. Review of 87 cases Circulation
1973; 48: 287-97.13 Bon Tempo CP, Ronan JA, De Leon AC, Twigg HL Radiographic appearance of the
thorax in the systolic click-late systolic murmur syndrome. Am J Cardiol 1975, 36:27-31.
14. Salomon J, Shah PM, Heinle RA. Thoracic skeletal abnormalities in idiopathic mitralvalve prolapse. Am J Cardiol 1975; 36: 32-36.
15 Udoshi MB, Shah A, Fisher VJ, Dolgin M. Incidence of mitral valve prolapse in sub-jects with thoracic skeletal abnormalities—a prospective study. Am Heart J1979. 97: 303-11.
16. Davies MK, Mackintosh P, Cayton RM, Page AJF, Shiu MF, Littler WA. The straighback syndrome. Quart J Med 1980, 49: 443-60.