Sensitivity and specificity of exercise ECG in heart diseaseBMJ 2008; 337 doi: https://doi.org/10.1136/bmj.a3098 (Published 24 December 2008) Cite this as: BMJ 2008;337:a3098
All rapid responses
I read with great interest this article and I agree with the Authors
on the major clinical relevance of the unsatisfactory sensitivity of
exercise ECG in heart disease.
However, an important remark should be done, in my opinion, concerning the
criteria to define a test as negative. Despite several markers of ischemia
are available from exercise ECG testing, the use of fixed magnitude of ST-
segment depression has been the leading approach in the majority of
clinical studies to distinguish between positive and negative response.
The intrinsic limitation of such a dichotomous interpretation is well
Two main theoretical assumptions have supported the evolution of ST-
segment analysis during the last years. The first hypothesizes that the
examination of the peak rate of ST depression as a function of the
increase in heart rate during developing ischemia should more accurately
reflect the severity of disease than does ST depression alone. The second
suggests that, since the relationship of ST-segment depression to
myocardial oxygen demand is non-linear during early recovery, the
resolution of ST depression during this phase lags behind its development
during exercise in case of significant coronary artery disease. Both these
assumptions have produced diagnostic indexes which proved to be more
accurate markers of myocardial ischemia than ST depression alone. The
combination of these with established clinical markers is expected to
significantly reduce the number of false negative results. Surprisingly,
no prospective study has been designed so far to assess this hypothesis.
In the meanwhile, the lack of confidence in the clinical utility of
exercise ECG is generating an increasing recourse to more expensive, less
available and sometimes less safe procedures.
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2. Bigi R, Cortigiani L, Gregori D, Bax JJ, Fiorentini C. Prognostic
value of combined exercise and recovery electrocardiographic analysis.
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Competing interests: No competing interests