1
540 One important stimulus to over-testing is the anxiety in- separable from clinical practice. There are few certainties in the diagnostic process, and the comforting (if sometimes spurious) precision of laboratory results has the same appeal to 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 desirable reasons for excessive testing, of course. "Just in case" tests are ordered by the junior lest he be surprised by a demand for a result by his consultant-martinet. "Routine tests" (exposed by Sandler) are ordered when habits are unthinkingly established. Such habits may account for the high incidence of repeat testing in the Harvard study. It is not only the junior doctor who orders unwisely, however. There are "ah-hah" tests; measurements known to be abnormal in certain conditions, which are ordered even when the diagnosis is established in order to satisfy curiosity or to advertise the cleverness of the clinician. An unwise search 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 physical examination would serve better, or where careful clinical review after a period would give the answer. ("Time is the best-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 order is of real value to the patient, provided he has the time and the information to obtain the right answer. Unit discussions and case-record reviews will assist. As the laboratory repertoire grows we may need computer-based information schemes, or automatic feedback, to tell the clinician the probability of a test’s providing useful data. Until such systems are evolved we can only urge thought before any request card is com- pleted. STRAIGHT-BACK SYNDROME TWENTY years ago a new syndrome appeared on the medical horizon, the straight-back syndrome.l,2 It had two main features-loss of the normal curvature of the upper dor- sal spine, leading to a decreased antero-posterior diameter of the chest with apparent squashing of the heart; and a systolic murmur heard over the base of the heart (originally attributed to torsion of the great vessels). Routine chest radiography suggested 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 were normal and the murmur was of extracardiac origin. The 1. Rawlings MS. The ’straight back’ syndrome, a new cause of pseudo-heart disease Am J Cardiol 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 Med 1963; 58: 938-45. 4. Datey KK, Deshmuki MM, Engineer SD, Dalvi CP Straight back syndrome. Br Heart J 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 and thrill 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 systolic murmurs. Am J Med 1967; 42: 309-13. symptomless syndrome was judged benign and compatible with normal employment and life expectancy. Of course, some patients with rheumatic or congenital heart disease had straight backs, but here the signs of organic heart disease would 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. 10 Over the same period a second syndrome began to attract attention-the "mitral-valve-prolapse" syndrome in which systolic clicks and murmurs arose from a floppy mitral valve." Surprisingly, a high percentage of mitral-valve- prolapse patients proved to have some form of spinal deformi- ty including pectus excavatum, scoliosis, and straight backs. 12-14 In a prospective study of mitral-valve prolapse in patients 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 tissue defect, since the mitral valve undergoes final differentiation at 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’s syndrome.14 The inevitable conclusion was that no longer should "pseudo-heart-disease" be diagnosed until mitral valve prolapse had been excluded. Further evidence for the association between skeletal abnormality and mitral valve prolapse has been offered by Davies and colleagues,16 who were asked to see 31 people with straight back syndrome and who identified the condition also in 27 near relatives. Of the 58 subjects, two-thirds had evidence of mitral-valve prolapse. There were no important respiratory abnormalities. No association was found between any particular HLA antigen and the straight-back syndrome, and the findings pointed to an autosomal dominant disorder. (It is noteworthy that mitral valve prolapse may also be a familial disorder with an autosomal 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 a straight back? No longer is "pseudo-heart-disease" a suitable label; no longer should murmurs be regarded as due to pressure on the heart, but rather as due to associated mitral valve prolapse; and anyone referred with straight-back syn- drome should be evaluated for mitral-valve prolapse. If this is the cause of the murmur, investigation need to be taken no further, sparing the patient and relatives much anxiety. For the research worker, the linking of these two disorders may help to unravel some of the curious relationships between developmental abnormalities and cardiac disease. 9. Gooch AS, Maranhao V, Goldberg H. The straight thoracic spine in cardiac diagnosis Am Heart J 1967; 74: 595-602. 10. Wennewold A, Stage P. The straight back syndrome related to intracardiac murmurs Dan 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 mitral valve 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 straigh back syndrome. Quart J Med 1980, 49: 443-60.

STRAIGHT-BACK SYNDROME

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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.

STRAIGHT-BACK SYNDROME

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.