Withholding thrombolysis in patients with diabetes mellitus and acute myocardial infarction.

The benefits of thrombolytic therapy in a patient with diabetes having a myocardial infarction are now well accepted but this treatment may be withheld inappropriately because of concerns about retinal haemorrhage. We therefore examined whether junior doctors alter their use of thrombolysis for the treatment of acute myocardial infarctions according to the type of diabetic retinopathy present. A questionnaire asking whether thrombolysis would be given to a 50-year-old male smoker with insulin-treated diabetes and an acute anterior MI was shown, with four unlabelled retinal photographs, to all doctors prescribing thrombolytic therapy in a south London teaching hospital and an affiliated district general hospital. In all, 24 medical SHOs, 16 medical registrars/specialist registrars, 3 medical senior registrars, and 23 casualty SHOs were interviewed. Of these 89% would thrombolyse such a patient with normal fundi, 55% with background diabetic retinopathy, 54 % if this also involved the macula, and 26% if they saw proliferative retinopathy. The more senior grades were more aggressive in their approach. As we believe that all patients with an acute anterior myocardial infarction and diabetes should be considered for thrombolysis irrespective of their retinal appearance these results suggest thrombolytic therapy is being withheld inappropriately.