Mersey has changed its policy

EDITOR,—We agree with Helen Ward and John S Yudkin that diabetic retinopathy should not be a contraindication to the use of thrombolysis in myocardial infarction.1 In September 1991 one of us (RCW) expressed concern locally that the practical difficulty of excluding diabetic retinopathy could easily lead to diabetic patients being denied thrombolysis. The need for a rapid decision, often without the benefit of case notes and after opiate analgesia, posed particular problems for the receiving team.

Subsequently, discussion took place in Mersey region among diabetologists, ophthalmologists, and cardiologists in their respective subcommittees of the regional medical committee. It was agreed that diabetic retinopathy should no longer be regarded as a contraindication to thrombolysis for two reasons: firstly, the potential benefits of a lifesaving treatment outweigh the possible harm of a complication that is not life threatening; and, secondly, even if a vitreous haemorrhage does occur the prognosis for vision is relatively good, especially with the widespread availability of vitrectomy.

In October 1993 the Mersey regional thrombolysis policy was modified to state that “proliferative diabetic retinopathy is no longer regarded as an absolute contraindication to thrombolysis.” We are unaware of any cases of vitreous haemorrhage in patients with diabetes receiving thrombolysis for myocardial infarction since then.

We are sceptical about Ward and Yudkin's suggestion that patients should have a voice in the decision about whether they should receive thrombolysis. Surely this is already a time of crisis for the patients, when their judgment may be clouded by anxiety and the effect of drugs. They should be spared the further stress of a discussion about a treatment that seems to have such clear overall benefit.

Finally, we are pleased to note that future editions of the British National Formulary will state that caution is required in diabetic retinopathy rather than that the condition is a contraindication. We wonder, however, whether such a caution can still be justified.