I read the article by Reuben and Mann1 with considerable interest. This is a useful way of presenting the Sgarbossa criteria, which have high specificity for acute myocardial infarction (AMI). Unfortunately, these criteria are far too insensitive to exclude MI, being present in only 20% of patients with left bundle branch block (LBBB) and confirmed AMI.2,3 It is therefore important that less experienced practitioners do not assume that thrombolysis should be withheld if these electrocardiographic (ECG) features are absent.
In fact the simplest thrombolysis decision is that all patients with a history strongly suggestive of AMI and LBBB should receive thrombolysis, unless significant contraindications exist. Even the well rehearsed medical myths relating to the age of the LBBB are of minimal relevance, as described in an elegant editorial cited by the authors.4 Patients with LBBB have the most to gain from thrombolysis,5 but they are still failing to receive this highly effective therapy in too many cases.
In summary, therefore, where Sgarbossa criteria are seen on the ECG, AMI is highly likely. However, even in the absence of these features patients with a convincing history of AMI and LBBB should still receive thrombolysis, unless there are compelling reasons not to.
Footnotes
Competing interests: none declared
References
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