Chest wall syndrome (CWS), the main cause of chest pain in primary care practice,
is most often an exclusion diagnosis. We developed and evaluated a clinical
prediction rule for CWS.
Data from a multicenter clinical cohort of consecutive primary care patients with
chest pain were used (59 general practitioners, 672 patients). A final diagnosis
was determined after 12 months of follow-up. We used the literature and bivariate
analyses to identify candidate predictors, and multivariate logistic regression
was used to develop a clinical prediction rule for CWS. We used data from a German
cohort (n = 1212) for external validation.
From bivariate analyses, we identified six variables characterizing CWS: thoracic
pain (neither retrosternal nor oppressive), stabbing, well localized pain, no
history of coronary heart disease, absence of general practitioner’s
concern, and pain reproducible by palpation. This last variable accounted for 2
points in the clinical prediction rule, the others for 1 point each; the total
score ranged from 0 to 7 points. The area under the receiver operating
characteristic (ROC) curve was 0.80 (95% confidence interval 0.76-0.83) in the
derivation cohort (specificity: 89%; sensitivity: 45%; cut-off set at 6 points).
Among all patients presenting CWS (n = 284), 71% (n = 201)
had a pain reproducible by palpation and 45% (n = 127) were correctly
diagnosed. For a subset (n = 43) of these correctly classified CWS
patients, 65 additional investigations (30 electrocardiograms, 16 thoracic
radiographies, 10 laboratory tests, eight specialist referrals, one thoracic
computed tomography) had been performed to achieve diagnosis. False positives
(n = 41) included three patients with stable angina (1.8% of all
positives). External validation revealed the ROC curve to be 0.76 (95% confidence
interval 0.73-0.79) with a sensitivity of 22% and a specificity of 93%.
This CWS score offers a useful complement to the usual CWS exclusion diagnosing
process. Indeed, for the 127 patients presenting CWS and correctly classified by
our clinical prediction rule, 65 additional tests and exams could have been
avoided. However, the reproduction of chest pain by palpation, the most important
characteristic to diagnose CWS, is not pathognomonic.